0001628280-25-008786 | 10-K | XBRL Viewer

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Stockholders' Equity - Components of AOCI (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023	Dec. 31, 2022	Dec. 31, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total Equity	$ 1,387	$ 2,534	$ 2,431
Accumulated other comprehensive income (loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total Equity	(12)	(23)	$ 0	$ (167)	$ (152)
Available-for-sale securities unrealized gain (loss), net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total Equity	(3)	5
Postretirement benefit prior service credits (costs), net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total Equity	14	0
Postretirement benefit actuarial gain (loss), net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Total Equity	$ (23)	$ (28)

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

- Definition

Amount of equity (deficit) attributable to parent and noncontrolling interest. Excludes temporary equity.

+ References

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+ Details

Risk Management, Derivative Instruments and Hedging Activities - Statements of Operations Presentation (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Unrealized gain (loss) on commodity contracts	$ (63)	$ 52	$ 62	$ 625
Realized and unrealized gain (loss) on interest rate contracts	732	179	307	(120)
Interest rate derivatives
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Realized and unrealized gain (loss) on interest rate contracts	0	(4)	9	30
Energy Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Realized gain (loss) on commodity contracts	644	360	317	(613)
Fuel and Energy Purchases
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Realized gain (loss) on commodity contracts	(34)	(91)	(35)	127
Operating Revenues
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Unrealized gain (loss) on commodity contracts	60	55	42	677
Energy Expenses
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Unrealized gain (loss) on commodity contracts	$ (123)	$ (3)	$ 20	$ (52)

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2024

Share-Based Payment Arrangement [Abstract]

Schedule of Stock-based Compensation Expense

Stock-based compensation expense presented as “General and administrative” on the Consolidated Statement of Operations for the periods was:


	Successor
	Year Ended December 31, 2024		May 18 through December 31, 2023
Stock-based compensation expense	$	33	$	19
Income tax benefit	(8)		(2)
After-tax stock-based compensation expense	$	25	$	17

Schedule of Nonvested Performance-Based Units Activity

The following table summarizes the Company’s non-vested PSUs and changes during the year:


	Successor
	Units	Weighted-Average Grant Date Fair Value per Unit
Non-vested as of December 31, 2023 (Successor)	968,793	$	54.35
Granted	4,945	96.00
Forfeited	(17,391)	72.75

Non-vested as of December 31, 2024 (Successor)	956,347	$	54.23

Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions

The fair value of the PSUs was determined using a Monte Carlo valuation methodology based on the fair value of the underlying stock price at the grant date and the significant inputs and assumptions summarized below:


	Successor
	Year Ended December 31, 2024		May 18 through December 31, 2023
Volatility (a)	25	%	25	%
Expected term (in years)	2.4		3
Risk-free rate (b)	4.29	%	4.35% - 4.59%

__________________

(a) Derived from an option pricing method based on the average asset volatility of peer companies and the Company’s leverage ratio.

(b) Based on the U.S. constant maturity treasury rate with a term matching the expected time to the end of the performance measurement period.

Schedule of Nonvested Share RSUs Activity

The following table summarizes the Company’s non-vested RSUs and changes during the year:


	Successor
	Units	Weighted-Average Grant Date Fair Value per Unit
Non-vested as of December 31, 2023 (Successor)	845,269	$	48.46
Granted	56,346	121.89
Forfeited	(56,594)	55.01
Vested	(295,616)	48.90
Non-vested as of December 31, 2024 (Successor)	549,405	$	55.07

Postretirement Benefit Obligations (Tables)

12 Months Ended

Dec. 31, 2024

Retirement Benefits [Abstract]

Schedule of Funded Status

The aggregate funded status and the weighted average assumptions for the periods were:


	Pension Benefits
	Successor						Predecessor
	Year Ended December 31, 2024			May 18 through December 31, 2023			January 1 through May 17, 2023

Change in benefit obligation
Benefit obligation beginning balance	$	1,308		$	1,300		$	1,273
Service cost	2			2			1
Interest cost	63			40			25
Actuarial (gain) loss	(81)			20			6
Actual benefits paid	(105)			(55)			(34)
Resolved litigation settlement and other charges	15			1			—
Benefit obligation ending balance	$	1,202		$	1,308		$	1,271
Change in plan assets
Plan assets fair value beginning balance	975			997			994
Actual return on plan assets	(13)			24			35
Employer contributions	54			9			2
Actual benefits paid	(105)			(55)			(34)
Plan assets fair value ending balance	$	911		$	975		$	997
Funded status	$	(291)		$	(333)		$	(274)
Accumulated benefit obligation	$	1,202		$	1,308		$	1,271
Aggregate amounts of underfunded plans
Benefit obligation/Accumulated benefit obligation	1,202			1,308			1,271
Fair value of plan assets	911			975			997
Amounts recognized in accumulated other comprehensive income
Net (gain) loss	34			37			238
Total accumulated other comprehensive income	$	34		$	37		$	238
Assumptions
Discount rate	5.65		%	5.00		%	5.37		%
Interest crediting rate	6.00		%	6.00		%	6.00		%
Rate of compensation increase	3.45		%	3.45		%	3.45		%


	Other Postretirement Benefits
	Successor						Predecessor
	Year Ended December 31, 2024			May 18 through December 31, 2023			January 1 through May 17, 2023

Change in benefit obligation
Benefit obligation beginning balance	$	79		$	78		$	77
Service cost	1			1			—
Interest cost	3			2			1
Plan amendments	(21)			—			—
Actuarial (gain) loss	(3)			1			1
Plan participant contributions	2			2			1
Actual benefits paid	(9)			(5)			(4)
Benefit obligation ending balance	$	52		$	79		$	76
Change in plan assets
Plan assets fair value beginning balance	75			74			75
Actual return on plan assets	3			4			2

Plan participant contributions	2			2			1
Actual benefits paid	(9)			(5)			(4)
Plan assets fair value ending balance	$	71		$	75		$	74
Funded status	$	19		$	(4)		$	(2)

Aggregate amounts of underfunded plans
Benefit obligation / Accumulated benefit obligation	$	52		$	78		$	76
Fair value of plan assets	71			75			74
Amounts recognized in accumulated other comprehensive income
Net (gain) loss	(2)			(1)			4
Prior service cost (credit)	(20)			—			(4)
Total accumulated other comprehensive income	$	(22)		$	(1)		$	—
Assumptions
Discount rate	5.63		%	5.01		%	5.36		%
Rate of compensation increase	2.31		%	2.31		%	2.31		%

The funded status of each plan as of December 31, 2024 (Successor) was:


	Trust Asset Fair Value		Obligation Fair Value		Overfunded Status
Benefit Plan for UMWA Represented Retirees of Pennsylvania Mines, LLC	$	21	$	16	$	5
Coal Worker's Pneumoconiosis (Black Lung) Benefit Plan	9		5		4

Schedule of Net Benefit Costs

The components of net periodic benefit cost (credit), the amounts recognized in OCI and the associated weighted average assumptions for pension and other postretirement plans for the periods were:


	Pension Benefits
	Successor						Predecessor
	Year Ended December 31, 2024			May 18 through December 31, 2023			January 1 through May 17, 2023			Year Ended December 31, 2022
Net periodic benefit costs (credits):
Service cost	$	2		$	2		$	1		$	4
Interest cost	63			40			25			50
Expected return on plan assets	(66)			(41)			(30)			(68)
Amortization of net (gain) loss	—			—			2			27
Resolved litigation settlement and other charges	15			1			—			—
Net periodic defined benefit cost (credit)	14			2			(2)			13
Net actuarial (gain) loss	(3)			38			2			19
Reclassifications due to settlement and (or) curtailment:
Amortization of net (gain) loss	—			—			—			(27)
Total recognized in OCI	$	(3)		$	38		$	2		$	(8)
Total recognized in net periodic costs and OCI	$	11		$	40		$	—		$	5
Assumptions
Discount rate	5.00		%	5.12		%	5.41		%	2.97		%
Rate of compensation increase	3.45		%	3.45		%	3.45		%	3.45		%
Expected return on plan assets	7.25		%	7.25		%	7.50		%	5.75		%


	Other Postretirement Benefits
	Successor						Predecessor
	Year Ended December 31, 2024			May 18 through December 31, 2023			January 1 through May 17, 2023			Year Ended December 31, 2022
Net periodic benefit costs (credits):
Service cost	$	1		$	1		$	1		$	1
Interest cost	3			2			1			3
Expected return on plan assets	(4)			(2)			(2)			(4)
Amortization of prior service cost (credit)	(1)			—			—			(1)
Net periodic defined benefit cost (credit)	(1)			1			—			(1)
Net actuarial (gain) loss	(2)			(1)			—			(3)
Prior service credit	(21)			—			—			—
Reclassifications due to settlement and (or) curtailment:
Amortization of prior service cost (credit)	1			—			—			1
Amortization of net (gain) loss	—			—			—			(1)
Total recognized in OCI	$	(22)		$	(1)		$	—		$	(3)
Total recognized in net periodic costs and OCI	$	(23)		$	—		$	—		$	(4)
Assumptions
Discount rate	5.01		%	5.13		%	5.41		%	2.94		%
Rate of compensation increase	2.31		%	2.31		%	2.31		%	2.31		%
Expected return on plan assets	5.49		%	5.49		%	5.74		%	3.89		%
Health care grading trend rates (a)	7.10% to 4.40%			6.50% to 4.50%			6.50% to 4.50%			4.50		%

__________________

(a)Trend rates grading to 2027.

Schedule of Expected Benefit Payments

The forecasted undiscounted benefit payments to plan participants as of December 31, 2024 (Successor) were:


	2025		2026		2027		2028		2029		2030-2034
Pension plans	$	97	$	94	$	94	$	93	$	93	$	452
Other postretirement plans	6		6		5		5		4		18

Schedule of Defined Benefit Plan, Assets Target Allocations

The weighted-average target asset allocations for the pension plan assets as of December 31, 2024 (Successor) were:


	December 31, 2024
Equity securities	32	%
Debt securities	10	%
Other	7	%
Growth portfolio	48	%
Debt securities	35	%
Other	12	%
Immunizing portfolio	47	%
Liquidity portfolio	4	%
Total	100	%

The target asset allocations for other postretirement benefit assets as of December 31, 2024 (Successor) were:


	2024
Cash and cash equivalents	4	%
Equity securities	11	%
Debt securities	84	%
Total	100	%

Schedule of Fair Value of Plan Assets by Measurement

The classifications of pension plan asset fair value measurements within the fair value hierarchy were:


	Successor
	December 31, 2024				December 31, 2023
	Level 1		NAV		Total		Level 1		NAV		Total
Cash equivalents	$	—	$	100	$	100	$	—	$	169	$	169
Commingled equity securities	—		274		274		—		288		288
Commingled debt securities	—		286		286		—		301		301
Alternative and other investments	(15)		231		216		52		191		243
Receivables (payables), net (a)	—		—		35		—		—		(25)
Total trust funds	(15)		891		911		52		949		976
Restricted 401(h) assets (b)	—				—		—		—		(1)
Total plan assets	$	(15)	$	891	$	911	$	52	$	949	$	975

__________________

(a) Represents: (i) interest and dividends earned but not received; and (ii) net sold or purchased investments, but not settled.

(b) Other postretirement 401(h) benefits assets are a component of the pension plan master trust. Accordingly, these are excluded from pension plan assets.

The classifications of other postretirement benefit plan asset fair value measurements within the fair value hierarchy were:


	Successor
	December 31, 2024								December 31, 2023
	Level 1		Level 2		NAV		Total			Level 1		Level 2		NAV		Total
Cash equivalents	$	—	$	—	$	4	$	4		$	—	$	—	$	7	$	7
Commingled equity securities	—		—		10		10			—		—		9		9
U.S. Government debt securities	7		—		—		7			8		—		—		8
Corporate debt securities	—		18		—		18			—		16		—		16
Commingled debt securities	—		—		32		32			—		—		34		34
Total trust funds	7		18		46		71			8		16		50		74
Restricted 401(h) assets (a)	—		—		—		—			—		—		—		1
Total plan assets	$	7	$	18	$	46	$	71		$	8	$	16	$	50	$	75

__________________

(a) Other postretirement 401(h) benefits assets are a component of the pension plan master trust. Accordingly, these are reported as postretirement assets.

Fresh Start Accounting

12 Months Ended

Dec. 31, 2024

Plan of Reorganization [Abstract]

Fresh Start Accounting

3. Emergence from Restructuring

Voluntary Reorganization Under Chapter 11 of the U.S. Bankruptcy Code

In May 2022, TES and 71 of its subsidiaries voluntarily commenced the Restructuring under Chapter 11 of the U.S. Bankruptcy Code. TEC joined the Restructuring in December 2022. The Plan of Reorganization was approved by the requisite parties and confirmed by the bankruptcy court in late 2022, and was consummated and became effective in May 2023, when TEC, TES, and the other debtors emerged from the Restructuring.

Prior to and during the Restructuring, TES and its debtor subsidiaries reached a number of settlements with various stakeholders (including certain holders of claims under TES’s prepetition indebtedness, certain affiliates Riverstone Holdings, LLC (“Riverstone”) (which then held all of the equity in TEC), TEC, and the Official Committee of Unsecured Creditors), the terms of which were incorporated into the Plan of Reorganization. Under the settlements, the Company agreed to conduct a common equity rights offering, which certain holders of prepetition unsecured notes agreed to backstop in exchange for subscription rights to purchase 30% of the new equity issued plus a backstop premium payment in the form of cash and (or) new equity.

Restructuring Transactions and Emergence

The Restructuring transactions were completed, and the Company emerged from the Restructuring, on May 17, 2023. Pursuant to the Plan of Reorganization, among other things:

•Claims against TEC were paid in full in cash or reinstated. All existing equity interests in TEC were extinguished, and new equity interests in TEC were issued as follows:

•Holders of unsecured claims under TES’s prepetition indebtedness (including the backstopping holders) received: (i) TEC equity; and (ii) subscription rights to purchase additional TEC equity in the equity rights offering.

•The equity rights offering was consummated, resulting in $1.4 billion in net cash proceeds to the Company. The backstopping holders (i) fully exercised their subscription rights; (ii) were required to purchase additional unsubscribed-for TEC equity; and (iii) were paid the remaining portion of the backstop premium in the form of TEC equity.

•Riverstone received: (i) 1% of the equity in TEC; (ii) a contingent right to receive additional TEC equity or cash upon certain conditions following Emergence; and (iii) warrants to purchase additional TEC equity. In the third quarter 2023, Riverstone surrendered the warrants and waived its contingent right to additional TEC equity or cash in exchange for $40 million in cash.

•The existing intercompany ownership structure of the debtors remained in place and intercompany claims were extinguished.

•The Company consummated its exit financings, comprised of the RCF, TLB-1, TLC, TLC LCF, Bilateral LCF, and Secured Notes. The PEDFA 2009B and 2009C Bonds remained outstanding following the Restructuring.

•The proceeds of the equity rights offering and the exit financings, together with cash on hand, were used to fully repay the Company’s debtor-in-possession credit facilities and to pay $3.1 billion relating to other secured claims.

•Holders of other unsecured claims received interests in a designated $26 million pool of cash, to which Talen Montana subsequently contributed an additional $11 million from proceeds of the PPL/Talen Montana settlement. See Note 12 for additional information on the PPL/Talen Montana settlement.

4. Fresh Start Accounting

At Emergence, TES adopted fresh start accounting as: (i) the holders of existing voting shares before the consummation of the Plan of Reorganization received less than 50% of the voting shares of the Successor; and (ii) the reorganization value of TES’s assets immediately prior to confirmation of the Plan of Reorganization of $7.8 billion was less than the total of post-petition liabilities and allowed claims of $9.8 billion. Accordingly, TES allocated its reorganization value to its individual assets based on their estimated fair values.

Reorganization Value

Reorganization value is derived from an estimate of enterprise value, or the fair value of the Company’s interest-bearing debt and member’s equity. As negotiated in the Plan of Reorganization and related disclosure statement approved by the Bankruptcy Court, the enterprise value as of Emergence was $4.5 billion. Management engaged third-party valuation advisors to assist in estimating the enterprise value and allocating the enterprise value to the assets and liabilities for financial reporting purposes as of Emergence. Enterprise value assumptions incorporated: (i) economic and industry information relevant to the business; (ii) internal financial information and operating data; (iii) historical financial information; and (iv) financial projections and other applicable assumptions. The valuation techniques used to estimate the enterprise value as of Emergence included the income approach, market approach, and cost approach, with consideration of the exit market and nature of the applicable asset or liability subject to valuation.

The Company’s principal assets are generation facilities whose values were determined by a discounted cash flow analysis based on management’s latest outlook of the business through the end of their expected useful lives. The forward-looking projections considered: (i) company-specific factors, such as unit characteristics, plant dispatch, operating expenses, capital expenditures and estimated economic useful lives; and (ii) macroeconomic factors, such as capacity prices, energy prices, fuel prices, market supply and demand factors, inflation factors, and environmental regulations. Commodity prices used to estimate future cash flows in observable periods were primarily based on adjusted exchange prices, prices provided by brokers, or prices provided by price service companies that are corroborated by market data. Commodity prices for future unobservable periods used third party pricing services that incorporate industry standard methodologies that may consider the historical relationships among various commodities, modeled market prices, inflation assumptions, and other relevant economic measures. Future estimates for capital expenditures and operating expenses, such as major maintenance and employee compensation were estimated considering unit operating experience, recent historical financial information, and expected operating performance. The expected useful lives of the generation facilities were estimated through 2050 and incorporated expectations regarding the economic prospects of each unit, permitting and licensing, regulatory requirements, and (or) other considerations. The cash flow estimates incorporated a federal effective tax rate of 21% and the applicable state tax rate based on the location of each generation facility. The present value of expected future cash flows utilized a weighted average cost of capital discount rate that ranged from 8.5% to 46.5%. The discount rate utilized for nuclear generation was 8.5% and certain natural gas generation facilities were estimated near the low end of the range. Certain coal and natural gas generation units were estimated near the high end of the range. Discount rates for each generation facility considered, among other things, unit characteristics, fuel type, and market location.

The assumptions used to estimate the reorganization value considered all available evidence as of Emergence and are believed to be consistent with those used by the principal market participants and outlook for each generation facility and represent management’s best estimate of reorganization value. However, such assumptions are inherently uncertain and require judgment. Accordingly, changes to sensitive assumptions, which primarily include commodity prices and discount rates, would have a reasonable possibility of significantly affecting the measurement of the reorganization value. See below under “Fresh Start Adjustments” for additional information regarding assumptions used in the measurement of the Company’s various other significant assets and liabilities.

Upon the application of fresh start accounting, the Company preliminarily allocated the reorganization value to its individual assets based on their estimated fair values. The following table reconciles the Company’s enterprise value to the estimated reorganization value at Emergence:


	May 17, 2023
Enterprise value (a)	$	4,500
Plus: Cash and cash equivalents and Restricted cash and cash equivalents (b)	701
Plus: Current liabilities excluding long-term debt due within one year	514
Plus: Non-current liabilities excluding long-term debt and liability-classified warrants	1,234
Plus: Fair value of noncontrolling interest	110
Reorganization value to be allocated	$	7,059

__________________

(a)Excludes any value associated with noncontrolling interest.

(b)Excludes $52 million for payment of professional fees.

The following table reconciles TES’s enterprise value to the estimated fair value at Emergence:


	May 17, 2023
Enterprise value (a)	$	4,500
Plus: Cash and cash equivalents and Restricted cash and cash equivalents (b)	701
Less: Fair value of debt	(2,845)
Less: Liability-classified warrants	(35)
Fair value of member’s equity (c)	2,321
Plus: Fair value of noncontrolling interest	110
Fair value of equity	$	2,431

__________________

(a)Excludes any value associated with noncontrolling interest.

(b)Excludes $52 million for payment of professional fees.

(c)Issued in accordance with the Plan of Reorganization. Includes 59,028,843 shares of TEC common stock and $8 million of equity-classified warrants.

Consolidated Balance Sheet

The “Reorganization Adjustments” on the fresh start Consolidated Balance Sheet as of Emergence present the aggregate effect of the transactions contemplated by the Plan of Reorganization. The “Fresh Start Adjustments” present the preliminary fair value and other required adjustments as a result of applying fresh start accounting. The explanatory notes provide additional information related to the adjustments, the methods used to determine fair values, and significant assumptions.


	May 17, 2023
Assets	Predecessor		Reorganization Adjustments (a)			Fresh Start Adjustments			Successor
Cash and cash equivalents	$	1,302	$	(1,133)	(b)	$	—		$	169
Restricted cash and cash equivalents	240		426		(c)	(81)		(q)	585
Accounts receivable, net	148		(3)		(d)	—			145
Inventory, net	448		—			(141)		(r)	307
Derivative instruments	818		—			(632)		(q)	186
Other current assets	135		—			(5)		(s)	130
Total current assets	3,091		(710)			(859)			1,522
Property, plant and equipment, net	4,322		—			(458)		(t)	3,864
Nuclear decommissioning trust funds	1,465		—			—			1,465
Derivative instruments	37		—			(37)		(q)	—
Other noncurrent assets	146		(12)		(e)	74		(u)	208
Total Assets	$	9,061	$	(722)		$	(1,280)		$	7,059

Liabilities and Equity
Revolving credit facilities	$	848	$	(848)	(f)	$	—		$	—
Long-term debt, due within one year	1,005		(1,000)		(g)	—			5
Accrued interest	288		(284)		(h)	—			4
Accounts payable and other accrued liabilities	382		3		(i)	—			385
Derivative instruments	711		—			(654)		(q)	57
Other current liabilities	414		(349)		(j)	3		(v)	68
Total current liabilities	3,648		(2,478)			(651)			519
Long-term debt	2,504		281		(k)	55		(w)	2,840
Liabilities subject to compromise	2,788		(2,788)		(l)	—			—
Derivative instruments	135		—			(93)		(q)	42
Postretirement benefit obligations	(1)		302		(m)	34		(x)	335
Asset retirement obligations and accrued environmental costs	580		202		(m)	(340)		(y)	442
Deferred income taxes	82		283		(n)	(8)		(z)	357
Other noncurrent liabilities	19		60		(o)	14		(aa)	93
Total Liabilities	9,755		(4,138)			(989)			4,628
Member’s equity	(818)		3,416		(p)	(277)		(bb)	2,321
Noncontrolling interests	124		—			(14)		(cc)	110
Total Equity	(694)		3,416			(291)			2,431
Total Liabilities and Equity	$	9,061	$	(722)		$	(1,280)		$	7,059

Reorganization Adjustments

The reorganization adjustments required in connection with the application of fresh start accounting and the allocation of the enterprise value were:

(a)Emergence adjustments for the implementation of the Plan of Reorganization. Such adjustments include: (i) settlement of prepetition liabilities subject to compromise; (ii) payment of certain prepetition indebtedness; (iii) issuances of member’s equity; (iv) recognition of new indebtedness and related restricted cash; and (v) other items.

(b)The uses of “Cash and cash equivalents” at Emergence resulting from the implementation of the Plan of Reorganization were:


Proceeds from rights offering	$	1,400
Proceeds from TLB-1 and TLC	1,019
Proceeds from Secured Notes	1,200
Release of restricted cash	89
Payment of claims under prepetition senior secured revolving credit facility	(1,029)
Payment of claims under other prepetition secured indebtedness	(2,136)
Payment of debtor-in-possession term loan	(1,012)
Restriction of cash relating to TLC LCF	(470)
Payment of debt issuance costs on exit financing (TLB-1, TLC, and Secured Notes)	(54)
Funding of professional fees escrow account	(52)
Payment of hedge rejections	(42)
Payment to general unsecured creditors trust	(26)
Payment of professional fees	(22)
Other (a)	2
Total uses of Cash and cash equivalents	$	(1,133)

__________________

(a)Includes $1 million of proceeds from Riverstone for payment to general unsecured creditors trust.

(c)“Restricted cash and cash equivalents” net change:


Restriction of cash relating to TLC LCF	$	470
Funding of professional fees escrow account	52
Release of restricted cash	(89)
Payment of professional fees	(7)
Net change in Restricted cash and cash equivalents	$	426

(d)“Accounts receivable, net” net change related to settlement of affiliate receivables.

(e)“Other noncurrent assets” net change:


Write-off of debt issuance costs associated with prepetition senior secured revolving credit facility	$	(22)
Reclassification of previously capitalized debt issuance costs to Long-term debt	(14)
Capitalization of debt issuance costs	24
Net change in Other noncurrent assets	$	(12)

(f)Payment of principal amounts owed under prepetition senior secured revolving credit facility.

(g)Repayment of debtor-in-possession credit facilities.

(h)“Accrued interest” net change:


Payment of accrued interest on prepetition senior secured revolving credit facility	$	(183)
Payment of accrued interest on other prepetition secured indebtedness	(89)
Payment of accrued interest on debtor-in-possession credit facilities	(12)
Net change in Accrued interest	$	(284)

(i)“Accounts payable and other accrued liabilities” net change:


Payment of hedge contract rejections	$	(42)
Payment of professional fees	(6)
Reinstatement of liabilities subject to compromise	38
Accrual for professional fees incurred at Emergence	13
Net change in Accounts payable and other accrued liabilities	$	3

(j)“Other current liabilities” net change:


Issuance of equity for backstop premium	$	(380)
Reinstatement of liabilities subject to compromise	31
Net change in Other current liabilities	$	(349)

(k)“Long-term debt” net change:


Payment of claims under prepetition secured indebtedness	$	(2,048)
Borrowings of $1.2 billion under the Secured Notes (a)	1,179
Borrowings of $580 million under TLB-1 (b)	548
Borrowings of $470 million under TLC (c)	446
Reinstatement of PEDFA 2009B Bonds and PEDFA 2009C Bonds (d)	130
Write-off of prepetition secured indebtedness issuance costs	26
Net change in Long-term debt	$	281

______________

(a)Net of an aggregate initial purchaser discount and debt issuance costs of $21 million.

(b)Net of an aggregate original issue discount and debt issuance costs of $32 million.

(c)Net of an aggregate original issue discount and debt issuance costs of $24 million.

(d)Includes recognition of $4 million of interest expense.

(l)“Liabilities subject to compromise” settled or reinstated at Emergence in accordance with the Plan of Reorganization:


Liabilities subject to compromise prior to Emergence
Debt	$	1,555
Termination of retail contracts	447
Postretirement benefit obligations	305
Asset retirement obligations and accrued environmental costs	220
Other liabilities	92
Deferred tax liabilities	77
Accounts payable and accrued liabilities	51
Accrued interest	41
Total	2,788

Reinstatement and settlements of certain Liabilities subject to compromise
Reinstatement of liabilities subject to compromise (a)	(801)
Excess fair value ascribed to lenders participating in rights offering	(315)
Issuance of member’s equity to holders of claims under prepetition unsecured notes and PEDFA 2009A Bonds	(186)
Payment to general unsecured creditors trust	(24)
Total	(1,326)
Gain on derecognition of certain Liabilities subject to compromise (b)	$	1,462

______________

(a)Primarily includes postretirement benefit obligations, AROs, and deferred income taxes.

(b)Represents liabilities subject to compromise that were discharged in accordance with the Plan of Reorganization.

(m)Reinstatement of “Liabilities subject to compromise.”

(n)“Deferred income taxes” net change:


Increase in deferred tax liabilities primarily due to estimated tax attribute reduction from the recognition of cancellation of debt income, partially offset by change in valuation allowance	$	206
Reinstatement of liabilities subject to compromise	77
Net change in Deferred income taxes	$	283

(o)“Other noncurrent liabilities” net change:


Issuance of liability-classified warrants	$	35
Reinstatement of liabilities subject to compromise	25
Net change in Other noncurrent liabilities	$	60

The estimated fair value of liability-classified warrants was determined using a Black-Scholes Option Pricing Model with the following assumptions at Emergence:


Expected volatility	30		%
Expected term (years)	5
Expected dividend yield	—		%
Risk-free interest rate	3.6		%
Strike price per share	$	52.92
Fair value per share	$	11.29

(p)“Member’s equity” net change:


Gain on settlement of liabilities subject to compromise	$	1,462
Other losses attributable to gain on debt discharge	(3)
Gain on debt discharge	1,459
Write-off of deferred financing cost	(46)
Professional fees expensed at Emergence	(27)
Restructuring-related compensation expense	(8)
Total reorganization items from reorganization adjustments	1,378
Interest expense incurred at Emergence	(4)
Income from reorganization adjustments before income taxes	1,374
Income tax expense	(206)
Net income from reorganization adjustments	1,168
Issuance of member’s equity in connection with rights offering	1,715
Issuance of member’s equity for backstop premium	380
Issuance of member’s equity to holders of claims under prepetition unsecured notes and PEDFA 2009A Bonds	186
Issuance of equity-classified warrants	8
Issuance of liability-classified warrants	(35)
Other (a)	(6)
Net change in Member’s equity	$	3,416

______________

(a)Includes $1 million of proceeds from Riverstone for payment to general unsecured creditors trust.

Fresh Start Adjustments

(q)Net presentation of derivatives on the Consolidated Balance Sheets. See Note 2 for additional information on the related accounting policy.

(r)“Inventory, net” fair value adjustments:


Coal	$	(33)
Oil products	11
Materials and supplies	(133)
Environmental products	14
Total adjustment to Inventory, net	$	(141)

The fair values for oil, coal and environmental products were estimated using current market prices. The fair values of materials and supplies were estimated using an indirect cost approach. The cost approach estimates fair value by considering the amount required to construct or purchase a new asset of equal utility at current prices, with adjustments for asset function, age, physical deterioration, and obsolescence.

(s)“Other current assets” primarily represents miscellaneous fair value adjustments.

(t)“Property, plant and equipment, net” fair value adjustments:


Electric generation	$	(350)
Other property and equipment	(80)
Intangible assets	(65)
Capitalized software	(3)
Construction work in progress	40
Total adjustment to Property, plant and equipment, net	$	(458)

The fair value of “Property, plant and equipment, net” was estimated using the income approach, market approach and cost approach, as applicable. The fair value of land was estimated utilizing the market approach, which considered comparable market-based transactions within a defined area based on size, use and utility.

(u)“Other noncurrent assets” fair value adjustments:


Favorable supply contracts (a)	$	109
Fair value adjustment to equity method investments	3
Eliminate debt issuance costs associated with debtor-in-possession credit facilities	(29)
Fair value reduction to other miscellaneous assets	(9)
Total adjustment to Other noncurrent assets	$	74

__________________

(a)The fair value of supply contracts was determined utilizing the present value of the after-tax difference between the pricing of actual contracts in place and a current market benchmark.

(v)“Other current liabilities” fair value adjustments, primarily related to short-term AROs.

(w)“Long-term debt” fair value adjustments:


Eliminate debt issuance costs associated with prepetition secured notes, prepetition TLB and LMBE-MC TLB	$	48
Fair value adjustment to Cumulus Digital TLF	11
Fair value adjustment to LMBE-MC TLB	(4)
Total adjustment to Long-term debt	$	55

Fair value adjustments to “Long-term debt” were determined using a lattice model, given that the debt can be prepaid by the borrower prior to the maturity date.

(x)Change in accounting policy for discount rates used to estimate postretirement obligations from a bond-matching model to yield curve approach. See Note 2 for additional information.

(y)Adjustment to present at fair value AROs using assumptions as of Emergence, including an inflation factor of 2%-3% and an estimated 5- to 20-year credit-adjusted risk-free rate of 8%-12%based on timing of cash flows for each underlying obligation.

(z)Adjustment to “Deferred income taxes” for the change in financial reporting basis of assets and liabilities as a result of the adoption of fresh start accounting.

(aa)Fair value adjustments primarily related to unfavorable supply contracts of $13 million and the recognition of unfavorable lease liabilities. The fair value of supply contracts was determined utilizing the present value of the after-tax difference between the pricing of actual contracts in place and current market benchmarks.

(bb)Cumulative impact of fresh start accounting adjustments presented herein.

(cc)“Noncontrolling interests” fair value adjustments for certain subsidiaries.

Liabilities Subject to Compromise

As of December 31, 2022 (Predecessor), prepetition liabilities and obligations whose treatment and satisfaction were dependent on the outcome of the Restructuring were presented as “Liabilities subject to compromise” on the Consolidated Balance Sheets. The carrying value of prepetition liabilities that were subject to compromise are presented at the best estimate of the claim amount permitted by the Bankruptcy Court. Such amounts presented as “Liabilities subject to compromise” on the Consolidated Balance Sheets were subject to adjustments depending on bankruptcy court actions, developments with respect to disputed claims, determination of secured status of certain claims, the determination as to the value of any collateral securing claims, proof of claims and (or) other events.


	Predecessor
	December 31, 2022
Debt (a)	$	1,558
Termination of retail power and other contracts	447
Postretirement benefit obligations (a)	309
Asset retirement obligations and accrued environmental costs (a)	219
Other liabilities (a)	114
Deferred tax liabilities	83
Accounts payable and accrued liabilities	53
Accrued interest	41
Derivatives (a)	1
Liabilities Subject to Compromise	$	2,825

__________________

(a)Includes both current and noncurrent amounts.

Reorganization Income (Expense), net

“Reorganization income (expense), net” for the relevant periods were:


	Predecessor
	January 1 through May 17, 2023		Year Ended December 31, 2022
Backstop premium	$	(70)	$	(310)
Gain (loss) on debt discharge	1,459		—
Gain (loss) on revaluation adjustments	(460)		—
Professional fees	(56)		(210)
Make-whole premiums and accrued interest on certain indebtedness	(21)		(183)
Professional fees incurred to obtain the debtor-in-possession credit facilities	—		(70)
Write-off of deferred financing cost and original issue discount	(46)		(30)
Other	(7)		(9)
Reorganization Income (Expense), net	$	799	$	(812)

In the preceding table, make-whole premiums and accrued interest on certain indebtedness primarily represents charges recognized by the debtors for estimates related to make-whole premiums and accrued interest, where applicable, on the prepetition senior secured revolving credit facility and certain other prepetition secured indebtedness. As of the bankruptcy petition date, the debtors ceased recognizing interest expense on certain outstanding unsecured or under-secured prepetition indebtedness. Contractual interest expense represented amounts due under the terms of outstanding prepetition indebtedness. The charges are presented as “Reorganization income (expense), net” on the Consolidated Statements of Operations and included in “Accrued interest” on the Consolidated Balance Sheets.

Cash paid for certain reorganization expenses was $308 million for the period from January 1 through May 17, 2023 (Predecessor). Cash paid for the year ended December 31, 2022 (Predecessor) for debtor-in-possession credit facilities financing fees is presented as “Financing Activities” on the Consolidated Statements of Cash Flows.

Consolidated Statements Of Operations - USD ($) shares in Thousands, $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Operating revenues	$ 1,210	$ 1,344	$ 2,115	$ 3,089
Fuel and energy purchases	(176)	(424)	(694)	(938)
Nuclear fuel amortization	(33)	(108)	(123)	(94)
Unrealized gain (loss) on derivative instruments (Note 5)	(123)	(3)	20	(52)
Energy Expenses	(332)	(535)	(797)	(1,084)
Operating Expenses
Operation, maintenance and development	(285)	(358)	(592)	(610)
General and administrative	(51)	(93)	(163)	(106)
Depreciation, amortization and accretion	(200)	(165)	(298)	(520)
Impairments (Note 10)	(381)	(3)	(1)	0
Operational restructuring	0	0	0	(488)
Other operating income (expense), net	(37)	(30)	(38)	(40)
Operating Income (Loss)	(76)	160	226	241
Nuclear decommissioning trust funds gain (loss), net (Note 9)	57	108	178	(184)
Interest expense and other finance charges (Note 13)	(163)	(176)	(238)	(359)
Reorganization income (expense), net (Note 4)	799	0	0	(812)
Consolidation of subsidiary gain (loss) (Note 2)	0	0	0	(170)
Gain (loss) on sale of assets, net (Note 20)	50	7	884	0
Other non-operating income (expense), net	10	95	61	(44)
Income (loss) before income taxes	677	194	1,111	(1,328)
Income tax benefit (expense)	(212)	(51)	(98)	35
Net Income (Loss)	465	143	1,013	(1,293)
Less: Net income (loss) attributable to noncontrolling interest	(14)	9	15	(4)
Net Income (Loss) Attributable to Stockholders (Successor) / Member (Predecessor)	$ 479	$ 134	$ 998	$ (1,289)
Per Common Share (Successor)
Net Income (Loss) Attributable to Stockholders - Basic (in dollars per share)		$ 2.27	$ 18.40
Net Income (Loss) Attributable to Stockholders - Diluted (in dollars per share)		$ 2.26	$ 17.67
Weighted-Average Number of Common Shares Outstanding - Basic (in shares)	0	59,029	54,254	0
Weighted-Average Number of Common Shares Outstanding - Diluted (in shares)	0	59,399	56,486	0
Capacity revenues
Operating revenues	$ 108	$ 133	$ 192	$ 377
Energy and other revenues
Operating revenues	1,042	1,156	1,881	2,035
Unrealized gain (loss) on derivative instruments (Note 5)
Operating revenues	$ 60	$ 55	$ 42	$ 677

Consolidated Statements of Cash Flows - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Operating Activities
Net Income (Loss)	$ 465	$ 143	$ 1,013	$ (1,293)
Non-cash reconciliation adjustments:
(Gain) loss on AWS Data Campus Sale and ERCOT Sale (Note 20)	0	0	(886)	0
Depreciation, amortization and accretion (Note 19)	208	157	285	549
NDT funds (gain) loss, net (excluding interest and fees) (Note 9)	(43)	(78)	(130)	227
Nuclear fuel amortization (Note 10)	33	108	123	94
Unrealized (gains) losses on derivative instruments (Note 5)	65	(40)	(69)	(647)
Deferred income taxes	195	55	(46)	(48)
Impairments (Note 10)	381	3	1	0
(Gain) loss on sales of assets, net	(50)	(7)	0	0
Reorganization (income) expense, net (Note 4)	(933)	0	0	99
Operational restructuring	0	0	0	488
Consolidation of subsidiary (gain) loss (Note 2)	0	0	0	170
Other (Note 19)	7	7	(26)	200
Changes in assets and liabilities:
Inventory, net	10	(68)	67	(55)
Accounts receivable	261	8	14	(298)
Other assets	98	147	(61)	(46)
Accounts payable and accrued liabilities	(69)	(49)	(69)	187
Accrued interest	(124)	28	(15)	250
Other liabilities	(42)	(12)	55	310
Net cash provided by (used in) operating activities	462	402	256	187
Investing Activities
NDT funds investment purchases (Note 9)	(959)	(1,290)	(2,295)	(2,271)
NDT funds investment sale proceeds (Note 9)	949	1,265	2,263	2,243
Proceeds from AWS Data Campus Sale and ERCOT Sale (Note 20)	0	0	1,398	0
Nuclear fuel expenditures (Note 10)	(49)	(45)	(104)	(80)
Property, plant and equipment expenditures (Note 10)	(138)	(116)	(85)	(232)
Equity investments in affiliates	(8)	(5)	(10)	(162)
Proceeds from the sale of assets	46	8	2	0
Increase (decrease) in cash and restricted cash due to consolidation of subsidiaries	0	0	0	123
Other investing activities	2	12	2	11
Net cash provided by (used in) investing activities	(157)	(171)	1,171	(368)
Financing Activities
Share repurchases (Note 18)	0	0	(1,958)	0
TES debt issuance (Note 13)	0	0	849	0
TES debt repayments (Note 13)	0	0	(479)	0
Cumulus Digital TLF repayment (Note 13)	0	(15)	(182)	0
Repurchase of noncontrolling interest (Note 18)	0	(19)	(125)	0
Cash settlement of restricted stock units	0	0	(32)	0
Exercise or repurchase of warrants (Note 18)	0	(40)	(16)	0
Deferred financing costs	(74)	(7)	(13)	(59)
LMBE-MC TLB payments	(7)	(294)	0	(52)
TLB-1 proceeds, net	0	288	0	0
Repayment of prepetition secured indebtedness (Note 4)	(3,898)	0	0	0
Financing proceeds at Emergence, net of discount (Note 4)	2,219	0	0	0
Contributions from member	1,393	0	0	0
Payment of make-whole premiums on prepetition secured indebtedness	(152)	0	0	0
Derivatives with financing elements	(20)	0	0	(104)
Debtor-in-possession credit facilities proceeds, net	0	0	0	987
Prepetition deferred capacity obligations repayments	0	0	0	(176)
Prepetition inventory repurchase obligations, net increase (decrease)	0	0	0	(165)
Prepetition senior secured revolving credit facility proceeds	0	0	0	62
Prepetition senior secured revolving credit facility repayments	0	0	0	(62)
Other	0	3	(7)	(5)
Net cash provided by (used in) financing activities	(539)	(84)	(1,963)	426
Net Increase (Decrease) in Cash and Cash Equivalents and Restricted Cash and Cash Equivalents	(234)	147	(536)	245
Beginning of period cash and cash equivalents and restricted cash and cash equivalents	988	754	901	743
End of period cash and cash equivalents and restricted cash and cash equivalents	$ 754	$ 901	$ 365	$ 988

Schedule I - Condensed Financial Information of Registrant

12 Months Ended

Dec. 31, 2024

Condensed Financial Information Disclosure [Abstract]

Condensed Financial Information of Parent Company Only Disclosure

Schedule I—Condensed Financial Information of Registrant

TALEN ENERGY CORPORATION
SCHEDULE I—CONDENSED FINANCIAL INFORMATION OF REGISTRANT
CONDENSED UNCONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME


	Successor
(Millions of Dollars, except share data)	Year Ended December 31, 2024		May 18 through December 31, 2023
Operating Revenue	$	—	$	—
Operating Expenses	—		—
Operating Income	—		—
Equity in earnings of TES	998		134
Income (Loss) Before Income Taxes	998		134
Income tax benefit (expense)	—		—
Net Income (Loss)	998		134
Other comprehensive income (loss)	11		(23)
Comprehensive Income (Loss)	$	1,009	$	111
Earnings Per Share of Common Stock:
Net Income (Loss) Attributable to Stockholders - Basic	$	18.40	$	2.27
Net Income (Loss) Attributable to Stockholders - Diluted	$	17.67	$	2.26
Weighted-Average Number of Common Shares Outstanding - Basic (in thousands)	54,254		59,029
Weighted-Average Number of Common Shares Outstanding - Diluted (in thousands)	56,486		59,399

The accompanying Notes to the Condensed Unconsolidated Financial Statements are an integral part of the financial statements.

TALEN ENERGY CORPORATION
SCHEDULE I—CONDENSED FINANCIAL INFORMATION OF REGISTRANT
CONDENSED UNCONSOLIDATED BALANCE SHEETS


	Successor
(Millions of Dollars, except share data)	December 31, 2024		December 31, 2023
Assets
Investment in TES	$	1,387	$	2,457
Total Assets	$	1,387	$	2,457




Total Liabilities	$	—	$	—

Stockholders’ Equity
Common stock ($0.001 par value, 350,000,000 shares authorized) (a)	—		—
Additional paid-in capital	1,725		2,346
Accumulated retained earnings (deficit)	(326)		134
Accumulated other comprehensive income (loss)	(12)		(23)
Stockholders’ Equity	1,387		2,457
Total Liabilities and Stockholders’ Equity	$	1,387	$	2,457

__________________

(a)Shares issued and outstanding were 45,961,910 and 59,028,843 as of December 31, 2024 (Successor) and December 31, 2023 (Successor), respectively.

The accompanying Notes to the Condensed Unconsolidated Financial Statements are an integral part of the financial statements.

TALEN ENERGY CORPORATION
SCHEDULE I—CONDENSED FINANCIAL INFORMATION OF REGISTRANT
NOTES TO CONDENSED UNCONSOLIDATED FINANCIAL STATEMENTS

1. Basis of Presentation

Talen Energy Corporation is a holding company whose only material businesses and properties are held through its direct and wholly owned subsidiary, Talen Energy Supply. Certain of TES’s debt agreements include covenants that restrict the payment of dividends or other distributions to TEC, restricting in excess of 25% of TEC’s consolidated net assets. Accordingly, these condensed unconsolidated financial statements and related footnotes have been prepared in accordance with Sections 5-04 and 12-04 of Regulation S-X. These statements should be read in conjunction with the Annual Financial Statements.

In May 2023, TEC and the majority of its subsidiaries emerged from the Restructuring and adopted fresh start accounting. See Notes 2, 3, and 4 to the Annual Financial Statements for additional information regarding the Restructuring and related accounting. Unconsolidated financial results are presented for TEC for the Successor periods for the year ended December 31, 2024 and the period from May 18 through December 31, 2023. Because the results presented in the Annual Financial Statements for Predecessor periods (prior to May 18, 2023) represent the operating results TES, such results are not repeated here. TEC held no cash nor had any cash activity during the year ended December 31, 2024 and the period from May 18 through December 31, 2023; therefore, a statement of cash flows has not been included.

Pursuant to the Internal Revenue Code, TEC and TES are each taxable entities. TEC files a consolidated U.S. federal income tax return on behalf of all its subsidiaries. The provision for income taxes and the effect of any recognition and (or) remeasurement are recognized as if: (i) TES and its subsidiaries file a consolidated income tax return; and (ii) TEC files a standalone income tax return. Additionally, the Company has elected to present accrued excise tax liabilities as a result of the repurchase of TEC common stock on the TES consolidated balance sheets. Accordingly, substantially all income taxes are recognized at TES.

2. TEC Indebtedness

For a general description of the material terms of TES’s indebtedness, see Note 13 to the Annual Financial Statements.

The agreements governing TES’s indebtedness restrict the ability of TES and the Subsidiary Guarantors to pay dividends or distributions or otherwise transfer assets to TEC, subject to certain exceptions. Notable exceptions include the ability to pay dividends or distributions: (1) in an amount not to exceed the greater of $420 million and 40% of TES’s consolidated adjusted EBITDA, (2) in an unlimited amount so long as TES’s pro forma consolidated total net leverage ratio is less than or equal to 2.5 to 1.0, and (3) in an amount not to exceed the sum of: (a) the greater of $525 million and 50% of TES’s consolidated adjusted EBITDA, (b) TES’s consolidated adjusted EBITDA minus 140% of TES’s consolidated interest expense, in each case, for the period beginning June 1, 2023 (subject to compliance with either (x) a pro forma consolidated total net leverage ratio of less than or equal to 3.75 to 1.0 or (y) a fixed charge coverage ratio greater than or equal to 2.0 to 1.0), (c) equity contributions to TES, and (d) other customary “builder basket” components.

TEC does not have any separate indebtedness, other long-term obligations, or mandatory dividend or redemption requirements of redeemable stocks.

As of December 31, 2024, no cash dividends have been paid to TEC in the last three fiscal years by any other entity.

3. Commitments and Contingencies

See Note 12 to the Annual Financial Statements for commitments and contingencies of TEC.

Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Income (loss) before income taxes	$ 677	$ 194	$ 1,111	$ (1,328)
Income tax benefit (expense)	$ (212)	$ (51)	$ (98)	$ 35
Effective tax rate	31.30%	26.30%	8.80%	2.60%
Federal income tax statutory tax rate	21.00%	21.00%	21.00%	21.00%
Income tax benefit (expense) computed at the federal income tax statutory tax rate	$ (143)	$ (41)	$ (234)	$ 279
Income tax increase (decrease) due to:
Change in valuation allowance	129	(43)	128	(198)
Nuclear PTC	0	0	46	0
Reorganization adjustments	(138)	26	23	0
Return to provision	0	0	11	0
Other permanent differences	(16)	22	3	(94)
Nuclear decommissioning trust taxes	(9)	(16)	(27)	28
State income taxes, net of federal benefit	(34)	1	(48)	19
Other	(1)	0	0	1
Income tax benefit (expense)	$ (212)	$ (51)	$ (98)	$ 35

Stock-Based Compensation - Assumptions Used to Calculate Fair Value of Awards (Details) - Performance stock units	7 Months Ended	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility	25.00%	25.00%
Expected term (in years)	3 years	2 years 4 months 24 days
Risk-free interest rate		4.29%
Risk-free interest rate, minimum	4.35%
Risk-free interest rate, maximum	4.59%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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-Topic 718
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-Paragraph 1D
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

Schedule I - Condensed Financial Information of Registrant - Notes to Condensed Unconsolidated Financial Statements (Details) - Parent Company $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($)
Condensed Financial Statements, Captions [Line Items]
Percentage of restricted net assets	25.00%
TEC
Condensed Financial Statements, Captions [Line Items]
Debt instrument, pro forma consolidated total net leverage ratio	3.75
Consolidated-adjusted earnings before interest taxes depreciations and amortization minus, percentage	140.00%
Debt instrument, fixed charge coverage ratio	2.0
TEC \| Threshold One
Condensed Financial Statements, Captions [Line Items]
Maximum adjusted EBITDA	$ 420
Percentage of Adjusted EBITDA	40.00%
TEC \| Threshold Two
Condensed Financial Statements, Captions [Line Items]
Maximum adjusted EBITDA	$ 525
Percentage of Adjusted EBITDA	50.00%
TEC \| Minimum
Condensed Financial Statements, Captions [Line Items]
Debt instrument, pro forma consolidated total net leverage ratio	2.5

Asset Retirement Obligations and Accrued Environmental Costs

12 Months Ended

Dec. 31, 2024

Asset Retirement Obligation Disclosure [Abstract]

Asset Retirement Obligations and Accrued Environmental Costs

11. Asset Retirement Obligations and Accrued Environmental Costs


	Successor
	December 31, 2024		December 31, 2023
Asset retirement obligations	$	498	$	464
Accrued environmental costs	21		23
Total asset retirement obligations and accrued environmental costs	519		487
Less: asset retirement obligations and accrued environmental costs due within one year (a)	51		18

Asset retirement obligations and accrued environmental costs due after one year	$	468	$	469

__________________

(a)Presented as “Other current liabilities” on the Consolidated Balance Sheets.

Asset Retirement Obligations

Certain subsidiaries of the Company have legal retirement obligations for the decommissioning and environmental remediation costs associated with our current and former generation, which include activities such as structure removal and remediation of coal piles, wastewater basins, and ash impoundments. Most of these obligations, except remediation of some ash impoundments, are not expected to be paid until several years, or decades, in the future. The most significant obligations are associated with the decommissioning of Susquehanna (for which the NDT is expected to fund) and coal ash disposal units associated with legacy coal-fired generation facilities (for which the Company has posted surety bonds and letters of credit for certain facilities). The carrying value of these obligations include assumptions of estimated future ARO cash expenditures, cost escalation rates, probabilistic cash flow models and discount rates. The ARO carrying value of AROs associated with legacy coal-fired generation facilities may be impacted by current or future EPA rulemaking. Additionally, as of December 31, 2024 (Successor), the fair values of certain AROs as a result of the EPA CCR Rule cannot be determined. See Note 12 for additional information on the EPA CCR Rule and the regulatory timeline that is expected to determine the associated scope of work.

Additionally, certain subsidiaries of the Company have legal retirement obligations associated with the removal, disposal, and (or) monitoring of asbestos-containing material at certain generation facilities. Given that the ultimate volume of asbestos-containing material is not yet known, the fair value of these obligations cannot be reasonably estimated. These obligations will be recognized upon a change in economic events or other circumstances which enables the fair value to be estimable.

The changes of the ARO carrying value during the periods were:


	ARO Rollforward
Carrying value, December 31, 2022 (Predecessor)	$	751
Obligations settled	(11)
Changes in estimates and (or) settlement dates	3
Accretion expense	23

Carrying value, May 17, 2023 (Predecessor)	$	766


Carrying value, May 18, 2023 (Successor)	$	766
Fair value adjustment at Emergence	(321)
Obligations settled	(11)
Accretion expense	30
Carrying value, December 31, 2023 (Successor)	$	464



Obligations settled	(13)
Changes in estimates and (or) settlement dates	(17)
Accretion expense	55
Obligations incurred	9
Carrying value, December 31, 2024 (Successor)	$	498

Supplemental information for the ARO:


	Successor
	December 31, 2024		December 31, 2023
Supplemental Information
Nuclear (a)	$	242	$	214
Non-Nuclear (b)	256		250
Carrying value	$	498	$	464

__________________

(a)Obligations are expected to be settled with available funds in the NDT at the time of decommissioning. See Note 14 for additional information on the NDT.

(b)Certain obligations are: (i) partially supported by surety bonds, some of which have been collateralized with cash and (or) LCs; or (ii) partially prefunded under phased installment agreements.

Susquehanna. Each joint owner of Susquehanna is obligated to fund their proportional share of Susquehanna's ARO. Talen’s proportionate share of decommissioning activities will be funded from the NDT when decommissioning commences in connection with the expiration of Susquehanna’s licenses. The licenses for Susquehanna Unit 1 and Unit 2 expire in 2042 and 2044, respectively, and can be extended subject to NRC approval. The NRC has jurisdiction over the decommissioning of nuclear power generation facilities and requires minimum decommissioning funding based upon a formula. Under the most recent calculation in 2022, the NDT exceeds the NRC's minimum funding requirements. Each joint owner of Susquehanna is obligated to fund their proportional decommissioning costs if their respective nuclear decommissioning trusts do not contain sufficient funds. We believe the NDT will be adequate to fund the Company’s proportionate share of decommissioning costs. As of December 31, 2024 (Successor), the fair value of the NDT was $1.7 billion and the carrying value the Company’s proportionate share of the Susquehanna ARO, which is discounted under a present value technique, was $242 million. See Note 2 for additional information on the measurement of AROs.

Talen Montana. Talen Montana has significant decommissioning and environmental remediation liabilities primarily consisting of its proportionate share of remediation, closure and decommissioning costs for coal ash impoundments at Colstrip. Due to the expected timing and scope of anticipated remediation activities, actual cash expenditures associated with these obligations are expected to materially increase over the next five years and will continue at a reduced spending level for several decades. Talen Montana, along with the other co-owners of Colstrip, are working with the Montana Department of Environmental Quality (the “MDEQ”) to define the scope of required remediation, the scope of closure and decommissioning activities, and an estimate of the costs, including the amount of necessary financial assurance necessary to backstop these obligations. Talen Montana's decommissioning and environmental remediation is expected to be paid by funds available to Talen Montana at the time of decommissioning.

Talen Montana's estimate of its proportionate share of the AROs, discounted using a credit adjusted risk-free rate, was $98 million at December 31, 2024 (Successor) and $107 million at December 31, 2023 (Successor).

As a result of environmental regulations issued by the EPA or other regulatory entities, the Company may be required to revise and (or) recognize new AROs. Future adjustments may be required to the Talen Montana ARO estimates due to the ongoing remediation requirements under MDEQ obligations and the EPA CCR Rule. If the assumptions underlying Talen Montana's estimates do not materialize as expected, actual cash expenditures and costs could be materially different than currently estimated. Moreover, regulatory changes and (or) changes resulting from required scope revisions on remediation activities could affect these obligations. See Note 12 for information on Talen Montana’s requirement to provide financial assurance for certain environmental decommissioning and remediation liabilities related to Colstrip.

Accrued Environmental Costs

Under the Pennsylvania Clean Streams Law, a Talen subsidiary is obligated to remediate acid mine drainage at a former mine site and may be required to take additional steps to prevent acid mine drainage at this site. Liabilities related to the remediation were $21 million and $23 million as of December 31, 2024 (Successor) and December 31, 2023 (Successor), respectively, and were presented as “Other current liabilities” and “Asset retirement obligations and accrued environmental costs” on the Consolidated Balance Sheets. Such liabilities were discounted based on a credit adjusted risk-free rate that was in existence at the time of initial liability recognition of 8.41%. The undiscounted amount of the liabilities was $32 million and $34 million as of December 31, 2024 (Successor) and December 31, 2023 (Successor).

Segments - Segments and Reconciliation (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Segment Reporting Information [Line Items]
Operating revenues	$ 1,210	$ 1,344	$ 2,115	$ 3,089
Operation, maintenance and development	285	358	592	610
Interest expense and other finance charges	163	176	238	359
Other segment items
Adjusted EBITDA
Capital expenditures	187	161	189	312
Operating Segments
Segment Reporting Information [Line Items]
Adjusted EBITDA	688	377	775	981
Corporate and Eliminations
Segment Reporting Information [Line Items]
Operating revenues	(37)	(173)	(118)	(7)
Operation, maintenance and development	(7)	(14)	0	(6)
Interest expense and other finance charges	163	176	238	359
Other segment items
Adjusted EBITDA
Capital expenditures	2	6	1	6
PJM \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenues	1,052	1,120	1,866	2,902
Operation, maintenance and development	245	294	518	519
Interest expense and other finance charges	0	0	0	0
Other segment items	119	449	573	1,402
Adjusted EBITDA	688	377	775	981
Capital expenditures	132	110	164	237
Other \| Operating Segments
Segment Reporting Information [Line Items]
Operating revenues	195	397	367	194
Operation, maintenance and development	47	78	74	97
Interest expense and other finance charges	0	0	0	0
Other segment items
Adjusted EBITDA
Capital expenditures	$ 53	$ 45	$ 24	$ 69

Postretirement Benefit Obligations - Projected Benefit Obligation (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Change in plan assets
Actual benefits paid	$ (38)	$ (60)	$ (114)
Assumptions
Interest crediting rate	6.00%	6.00%	6.00%
Pension Benefits
Change in benefit obligation
Benefit obligation beginning balance	$ 1,273	$ 1,271	$ 1,308
Service cost	1	2	2	$ 4
Interest cost	25	40	63	50
Actuarial (gain) loss	6	20	(81)
Actual benefits paid	(34)	(55)	(105)
Resolved litigation settlement and other charges	0	1	15	0
Benefit obligation ending balance	1,271	1,308	1,202	1,273
Benefit obligation ending balance	1,300
Change in plan assets
Plan assets fair value beginning balance	994	997	975
Actual return on plan assets	35	24	(13)
Employer contributions	2	9	54
Actual benefits paid	(34)	(55)	(105)
Plan assets fair value ending balance	997	975	911	$ 994
Funded status	(274)	(333)	(291)
Accumulated benefit obligation	1,271	1,308	1,202
Aggregate amounts of underfunded plans
Benefit obligation / Accumulated benefit obligation	1,271	1,308	1,202
Fair value of plan assets	997	975	911
Amounts recognized in accumulated other comprehensive income
Net (gain) loss	238	37	34
Total accumulated other comprehensive income	$ 238	$ 37	$ 34
Assumptions
Rate of compensation increase	3.45%	3.45%	3.45%	3.45%
Pension Benefits \| Pension Plan, Obligation
Assumptions
Discount rate	5.37%	5.00%	5.65%
Other Postretirement Benefits
Change in benefit obligation
Benefit obligation beginning balance	$ 77	$ 76	$ 79
Service cost	1	1	1	$ 1
Service cost	0
Interest cost	1	2	3	3
Plan amendments	0	0	(21)
Actuarial (gain) loss	1	1	(3)
Plan participant contributions	1	2	2
Actual benefits paid	(4)	(5)	(9)
Benefit obligation ending balance	76	79	52	77
Benefit obligation ending balance	78
Change in plan assets
Plan assets fair value beginning balance	75	74	75
Actual return on plan assets	2	4	3
Plan participant contributions	1	2	2
Actual benefits paid	(4)	(5)	(9)
Plan assets fair value ending balance	74	75	71	$ 75
Funded status	(2)	(4)	19
Aggregate amounts of underfunded plans
Benefit obligation / Accumulated benefit obligation	76	78	52
Fair value of plan assets	74	75	71
Amounts recognized in accumulated other comprehensive income
Net (gain) loss	4	(1)	(2)
Prior service cost (credit)	(4)	0	(20)
Total accumulated other comprehensive income	$ 0	$ (1)	$ (22)
Assumptions
Rate of compensation increase	2.31%	2.31%	2.31%	2.31%
Other Postretirement Benefits \| Other Postretirement Benefit Plan, Obligation
Assumptions
Discount rate	5.36%	5.01%	5.63%

Fresh Start Accounting - Schedule of Enterprise Value to Estimated Reorganization (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023
Plan of Reorganization [Abstract]
Enterprise value			$ 4,500
Plus: Cash and cash equivalents and Restricted cash and cash equivalents			701
Plus: Current liabilities excluding long-term debt due within one year			514
Plus: Non-current liabilities excluding long-term debt and liability-classified warrants			1,234
Plus: Fair value of noncontrolling interest	$ 0	$ 77	110
Reorganization value to be allocated			$ 7,059

- Definition

Amount of equity (deficit) attributable to noncontrolling interest. Excludes temporary equity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(31))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481687/323-10-50-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Subparagraph (f)
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-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.7-03(a)(24))
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (SX 210.6-04(19))
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Subparagraph (SX 210.13-01(a)(4)(i))
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-URI https://asc.fasb.org/1943274/2147480097/470-10-S99-1A

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(4)(iv))
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1A
-Subparagraph (SX 210.13-01(a)(5))
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://fasb.org/us-gaap/role/ref/legacyRef
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+ Details

Commitments and Contingencies - Legal Matters (Details) $ in Millions	1 Months Ended	7 Months Ended	12 Months Ended
	Dec. 31, 2023 lawsuit case	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Feb. 03, 2025 group	Jan. 31, 2025 group	Dec. 31, 2024 USD ($)
Other Commitments [Line Items]
Settlement agreement, reimbursement						$ 14
Settlement agreement, reimbursement received		$ 24	$ 7
Subsequent Event
Other Commitments [Line Items]
Number of plaintiff groups \| group				2	2
ERCOT Weather Event (Winter Storm Uri) \| Pending Litigation
Other Commitments [Line Items]
Number of suits \| lawsuit	5
Number of claims on appeal \| case	58

Stock-Based Compensation - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Jun. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)		7,083,461
Performance stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost	$ 24
Term over which compensation cost recognized (in years)	1 year 6 months
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost	$ 22
Term over which compensation cost recognized (in years)	1 year 6 months
Settled in cash	$ 32

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Property, Plant, and Equipment - Schedule of Property, Plant and Equipment (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023
Finite-Lived Assets
Gross Value	$ 3,619	$ 4,025
Accumulated Depreciation	(465)	(186)
Carrying Value	3,154	3,839	$ 3,864
Electric generation
Finite-Lived Assets
Gross Value	3,030	3,178
Accumulated Depreciation	(292)	(109)
Carrying Value	2,738	3,069
Nuclear fuel
Finite-Lived Assets
Gross Value	322	228
Accumulated Depreciation	(152)	(55)
Carrying Value	170	173
Other property and equipment
Finite-Lived Assets
Gross Value	90	358
Accumulated Depreciation	(18)	(21)
Carrying Value	72	337
Capitalized software
Finite-Lived Assets
Gross Value	8	6
Accumulated Depreciation	(3)	(1)
Carrying Value	5	5
Construction work in progress
Finite-Lived Assets
Gross Value	169	255
Carrying Value	$ 169	$ 255
Minimum \| Electric generation
Finite-Lived Assets
Estimated Useful Life (years)	3 years
Minimum \| Nuclear fuel
Finite-Lived Assets
Estimated Useful Life (years)	1 year
Minimum \| Other property and equipment
Finite-Lived Assets
Estimated Useful Life (years)	1 year
Minimum \| Capitalized software
Finite-Lived Assets
Estimated Useful Life (years)	1 year
Maximum \| Electric generation
Finite-Lived Assets
Estimated Useful Life (years)	27 years
Maximum \| Nuclear fuel
Finite-Lived Assets
Estimated Useful Life (years)	6 years
Maximum \| Other property and equipment
Finite-Lived Assets
Estimated Useful Life (years)	26 years
Maximum \| Capitalized software
Finite-Lived Assets
Estimated Useful Life (years)	5 years

Segments

12 Months Ended

Dec. 31, 2024

Segment Reporting [Abstract]

Segments

21. Segments

Talen’s operating segments are based on the market areas in which our generation facilities operate and reflect the manner in which our Chief Executive Officer, who is the chief operating decision maker, reviews results and allocate resources. Adjusted EBITDA is the key profit metric used to measure financial performance of each segment. Total assets or other asset metrics are not considered a key metric or reviewed by the chief operating decision maker.

“PJM” is engaged in electricity generation, marketing activities, commodity risk and fuel management within the PJM RTO or ISO markets and is comprised of Susquehanna and Talen’s natural gas and coal generation facilities.

“Other” represents an operating segment that includes the operating and marketing activities of Talen Montana’s proportionate share of Colstrip in the WECC market and other non-material operating and development activities. “Other” also includes the operating activities of Nautilus until Bitcoin mining operations were suspended in October 2024 and the operating activities of our Texas power generation facilities in the ERCOT market prior to their disposal in May 2024. We have determined it appropriate to aggregate results of Talen’s remaining non-reportable segments and other operating activities.

“Corporate and Eliminations” represents a non-reportable segment that includes: (i) general and administrative expenses incurred by our corporate function; (ii) interest expense and other corporate activities not allocated to our operating segments; and (iii) intercompany eliminations. This grouping is presented to reconcile the reportable segments to our consolidated results.

Financial results for the segments and reconciliation to consolidated results:


	PJM		Other		Corporate and Eliminations		Total
Year Ended December 31, 2024 (Successor)
Operating revenues	$	1,866	$	367	$	(118)	$	2,115
Operation, maintenance and development expenses (a)	518		74		—		592
Interest expense and other finance charges	—		—		238		238
Other segment items (b)	573
Adjusted EBITDA	775
Capital expenditures	164		24		1		189

May 18 through December 31, 2023 (Successor)
Operating revenues	$	1,120	$	397	$	(173)	$	1,344
Operation, maintenance and development expenses (a)	294		78		(14)		358
Interest expense and other finance charges	—		—		176		176
Other segment items (b)	449
Adjusted EBITDA	377
Capital expenditures	110		45		6		161


January 1 through May 17, 2023 (Predecessor)
Operating revenues	$	1,052	$	195	$	(37)	$	1,210
Operation, maintenance and development expenses (a)	245		47		(7)		285
Interest expense and other finance charges	—		—		163		163
Other segment items (b)	119
Adjusted EBITDA	688
Capital expenditures	132		53		2		187

Year ended December 31, 2022 (Predecessor)
Operating revenues	$	2,902	$	194	$	(7)	$	3,089
Operation, maintenance and development expenses (a)	519		97		(6)		610
Interest expense and other finance charges	—		—		359		359
Other segment items (b)	1,402
Adjusted EBITDA	981
Capital expenditures	237		69		6		312

__________________

(a)This significant segment expense category aligns with the segment-level information that is regularly provided to the CODM.

(b)Other segment items are primarily comprised of fuel and energy purchases.

Reconciliation of segment Adjusted EBITDA to Net Income (Loss):


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Adjusted EBITDA:
PJM	$	775	$	377	$	688	$	981
Total Segment Adjusted EBITDA	$	775	$	377	$	688	$	981
Reconciling Items:
Interest expense and other finance charges	$	(238)	$	(176)	$	(163)	$	(359)
Income tax benefit (expense)	(98)		(51)		(212)		35
Depreciation, amortization and accretion	(298)		(165)		(200)		(520)
Nuclear fuel amortization	(123)		(108)		(33)		(94)
Reorganization (gain) loss, net	—		—		799		(812)
Unrealized (gain) loss on commodity derivative contracts	62		52		(63)		625
Nuclear decommissioning trust funds gain (loss), net	178		108		57		(184)
Stock-based compensation expense	(33)		(19)		—		—
Long-term incentive compensation expense	(21)		(2)		—		—

Gain (loss) on asset sales, net	884		7		50		—
Non-cash impairments	(1)		(3)		(381)		—
Legal settlements and litigation costs	10		84		(1)		(20)
Unusual market events	1		19		(14)		(29)
Net periodic defined benefit cost	(14)		(2)		3		(12)
Operational and other restructuring activities	(76)		(48)		(17)		(570)
Hedge termination losses, net	—		—		—		(158)
Development expenses	(1)		(7)		(10)		(17)
Non-cash inventory net realizable value, obsolescence, and other charges	(20)		(4)		(56)		(3)
Consolidation of subsidiary gain (loss), net	—		—		—		(170)
"Other" operating segment	71		113		37		103
Noncontrolling interest	21		42		14		(3)
Corporate and Eliminations	(76)		(64)		(30)		(69)
Other items	10		(10)		(3)		(17)
Net Income (Loss)	$	1,013	$	143	$	465	$	(1,293)

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-34

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Paragraph 26C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-26C

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 26B
-Publisher FASB
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-42

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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Reference 20: http://www.xbrl.org/2003/role/disclosureRef
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Reference 21: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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-Paragraph 21
-Subparagraph (a)
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-Paragraph 21
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-Topic 280
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-Paragraph 32
-Subparagraph (e)
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-URI https://asc.fasb.org/1943274/2147482810/280-10-50-32

+ Details

Stockholder's Equity - Summary of Share Repurchase Program (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	6 Months Ended	12 Months Ended	37 Months Ended
	Jun. 30, 2024	Dec. 31, 2024	Dec. 31, 2024	Jun. 30, 2024
Related Party Transaction [Line Items]
Share repurchases (in shares)			13,227,222
Share repurchases (in dollars per share)	$ 117.16		$ 149.50
Share repurchases			$ 1,977
Share retirements (in shares)			(13,227,222)
Share retirements (in dollars per share)			$ 149.50
Share retirements			$ (1,977)
Share retirements, total amount			$ 0
Shares repurchased, tender offer (in shares)				5,275,862
Affiliated Entity
Related Party Transaction [Line Items]
Share repurchases (in shares)		7,307,300
Share repurchases (in dollars per share)		$ 177.16
Share retirements, total amount		$ 850

Inventory - Narrative (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
Inventory - Narrative (Details) - USD ($) $ in Millions	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Inventory [Line Items]
Net realizable value and obsolescence charges	$ 37	$ 0	$ 0	$ 0
Brandon Shores Inventory
Inventory [Line Items]
Net realizable value and obsolescence charges	$ 24

Commitments and Contingencies - Guarantees and Other Assurances (Details) - Surety Bond - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Other Commitments [Line Items]
Surety bonds	$ 234	$ 240
Subsidiary, TES
Other Commitments [Line Items]
Surety bonds	$ 125	$ 115

Income Taxes - Summary of Operating Loss Carryforwards (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Federal, expirations 2036 - 2037
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 0	$ 43
Federal, indefinite expiration, limited to annual utilization of 80%
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	783	1,258
State, expirations 2025 - 2043
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 310	$ 555

Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2024

Earnings Per Share [Abstract]

Schedule of Earnings Per Share

EPS for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Numerator: (Millions of Dollars)
Net Income (Loss)	$	1,013	$	143	$	465	$	(1,293)
Less:
Net income (loss) attributable to noncontrolling interest	15		9		(14)		(4)
Net Income (Loss) Attributable to Stockholders (Successor) / Member (Predecessor)	$	998	$	134	$	479	$	(1,289)

Denominator: (Thousands)
Weighted-Average Number of Common Shares Outstanding - Basic	54,254		59,029		—		—
Warrants	—		84		—		—
Restricted stock units	354		166		—		—
Performance stock units	1,878		120		—		—
Weighted-Average Number of Common Shares Outstanding - Diluted	56,486		59,399		—		—

Earnings per Share - Basic	$	18.40	$	2.27	N/A		N/A
Earnings per Share - Diluted	17.67		2.26		N/A		N/A

Revenue - Summary of Accounts Receivable (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023
Revenue from Contract with Customer [Abstract]
Customer accounts receivable	$ 66	$ 52
Other accounts receivable	57	85
Accounts receivable	$ 123	$ 137	$ 145

Fresh Start Accounting - Liabilities Subject To Compromise (Details) - USD ($) $ in Millions	May 17, 2023	Dec. 31, 2022
Reorganization, Chapter 11 [Line Items]
Debt		$ 1,558
Termination of retail power and other contracts		447
Postretirement benefit obligations		309
Asset retirement obligations and accrued environmental costs		219
Other liabilities		114
Deferred tax liabilities		83
Accounts payable and accrued liabilities		53
Accrued interest		41
Derivatives		1
Liabilities subject to compromise	$ 0	$ 2,825
Predecessor
Reorganization, Chapter 11 [Line Items]
Debt	1,555
Postretirement benefit obligations	305
Asset retirement obligations and accrued environmental costs	220
Other liabilities	92
Deferred tax liabilities	77
Accounts payable and accrued liabilities	51
Accrued interest	41
Liabilities subject to compromise	$ 2,788

Fair Value - Summary of Recurring Fair Value Measurements (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023
Assets
Cash equivalents	$ 3	$ 9
Equity securities, Fair Value	1,105	1,013
Debt securities	611	579
Receivables (payables), net	5	(26)
NDT funds	1,724	1,575	$ 1,465
Derivative assets, netting	(156)	(200)
Total assets	1,795	1,670
Liabilities
Derivative liabilities, netting	(167)	(257)
Total liabilities	7	43
Commodity derivatives
Assets
Derivative assets, netting	(156)	(200)
Derivative assets, total	69	94
Liabilities
Derivative liabilities, netting	(167)	(257)
Derivative liabilities, total	7	37
Interest rate derivatives
Assets
Derivative assets, total	2	1
Liabilities
Derivative liabilities, total	0	6
U.S. Government debt securities
Assets
Debt securities	353	337
Municipal debt securities
Assets
Debt securities	85	86
Corporate debt securities
Assets
Debt securities	173	156
Level 1
Assets
Cash equivalents	0	0
Equity securities, Fair Value	758	629
NDT funds	1,111	966
Total assets	1,245	1,064
Liabilities
Total liabilities	145	155
Level 1 \| Commodity derivatives
Assets
Derivative assets	134	98
Liabilities
Derivative liabilities	145	155
Level 1 \| Interest rate derivatives
Assets
Derivative assets, total	0	0
Liabilities
Derivative liabilities	0	0
Level 1 \| U.S. Government debt securities
Assets
Debt securities	353	337
Level 1 \| Municipal debt securities
Assets
Debt securities	0	0
Level 1 \| Corporate debt securities
Assets
Debt securities	0	0
Level 2
Assets
Cash equivalents	0	0
Equity securities, Fair Value	0	0
NDT funds	258	242
Total assets	351	439
Liabilities
Total liabilities	29	145
Level 2 \| Commodity derivatives
Assets
Derivative assets	91	196
Liabilities
Derivative liabilities	29	139
Level 2 \| Interest rate derivatives
Assets
Derivative assets, total	2	1
Liabilities
Derivative liabilities	0	6
Level 2 \| U.S. Government debt securities
Assets
Debt securities	0	0
Level 2 \| Municipal debt securities
Assets
Debt securities	85	86
Level 2 \| Corporate debt securities
Assets
Debt securities	173	156
NAV
Assets
Cash equivalents	3	9
Equity securities, Fair Value	347	384
NDT funds	350	393
Total assets	350	393
Liabilities
Total liabilities	0	0
NAV \| Commodity derivatives
Assets
Derivative assets	0	0
Liabilities
Derivative liabilities	0	0
NAV \| Interest rate derivatives
Assets
Derivative assets, total	0	0
Liabilities
Derivative liabilities	0	0
NAV \| U.S. Government debt securities
Assets
Debt securities	0	0
NAV \| Municipal debt securities
Assets
Debt securities	0	0
NAV \| Corporate debt securities
Assets
Debt securities	$ 0	$ 0

Emergence from Restructuring (Details) $ in Millions		1 Months Ended	3 Months Ended
Emergence from Restructuring (Details) $ in Millions	May 17, 2023 USD ($)	May 31, 2022 subsidiary	Sep. 30, 2023 USD ($)
Debt Instrument [Line Items]
Number of subsidiaries \| subsidiary		71
Proceeds from issuance or sale of equity	$ 1,400
Payments for other secured claims	3,100
Designated pool of cash	26
Common rights equity offering, subscription rights available for purchase, percent		0.30
PPL/Talen Montana Litigation \| Settled Litigation
Debt Instrument [Line Items]
Litigation settlement, remitted amount	$ 11
Riverstone
Debt Instrument [Line Items]
Common rights equity offering, receivable of additional equity, percent	1.00%
Payment in exchange for surrendered warrants			$ 40

Fresh Start Accounting - Reorganization Adjustments (Details) - USD ($) $ / shares in Units, $ in Millions		5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Cash and Cash Equivalents:
Proceeds from secured debt		$ 0	$ 288	$ 0	$ 0
Payment of debt issuance costs on exit financing (TLB-1, TLC, and Secured Notes)		(74)	(7)	(13)	(59)
Cash and cash equivalents	$ 169	169	400	328
Other noncurrent assets:
Net change in Other noncurrent assets	208	208	147	183
Accrued interest:
Accrued interest	4	4	32	18
Accounts payable and other accrued liabilities:
Net change in Accounts payable and other accrued liabilities	385	385	344	266
Other current liabilities:
Other current liabilities	68	68	69	154
Long-term debt:
Proceeds from secured debt		0	288	0	0
Total principal			2,849	3,038
Issuance of equity for backstop premium			29	34
Liabilities subject to compromise prior to Emergence
Debt					1,558
Postretirement benefit obligations					309
Asset retirement obligations and accrued environmental costs					219
Other liabilities					114
Deferred tax liabilities					83
Accounts payable and accrued liabilities					53
Accrued interest					41
Liabilities subject to compromise	0	0			2,825
Deferred income taxes:
Deferred income taxes (Note 7)	357	357	407	362
Other noncurrent liabilities:
Other noncurrent liabilities	93	93	35	135
Member’s equity:
Gain on debt discharge		1,459			0
Total reorganization items from reorganization adjustments		799	0	0	$ (812)
Total Stockholders' Equity	2,321	2,321	2,457	1,387
Secured Notes
Long-term debt:
Total principal	$ 1,200	$ 1,200	1,200	1,200
Warrant
Estimated fair value of liability-classified warrants:
Expected volatility	30.00%
Expected term (years)	5 years
Expected dividend yield	0.00%
Risk-free interest rate	3.60%
Strike price per share (in dollars per share)	$ 52.92	$ 52.92
Fair value per share (in dollars per share)	$ 11.29	$ 11.29
TLB-1 \| Secured Debt
Long-term debt:
Total principal	$ 580	$ 580	866	857
TLC \| Secured Debt
Long-term debt:
Total principal	470	470	$ 470	0
Reorganization Adjustments
Cash and Cash Equivalents:
Proceeds from rights offering	1,400
Proceeds from secured debt	1,019
Proceeds from Secured Notes	1,200
Release of restricted cash	89
Payment of claims under prepetition senior secured revolving credit facility	(1,029)
Payment of claims under other prepetition secured indebtedness	(2,136)
Payment of debtor-in-possession term loan	(1,012)
Restriction of cash relating to TLC LCF	470
Payment of debt issuance costs on exit financing (TLB-1, TLC, and Secured Notes)	(54)
Funding of professional fees escrow account	(52)
Payment of hedge rejections	(42)
Payment to general unsecured creditors trust	(26)
Payment of professional fees	(22)
Other	2
Cash and cash equivalents	(1,133)	(1,133)
Proceeds from receipt of payment for general unsecured creditors trust	1
Restricted cash and cash equivalents:
Restriction of cash relating to TLC LCF	470
Funding of professional fees escrow account	52
Release of restricted cash	(89)
Payment of professional fees	(7)
Net change in Restricted cash and cash equivalents	426	426
Other noncurrent assets:
Write-off of debt issuance costs associated with prepetition senior secured revolving credit facility	(22)
Reclassification of previously capitalized debt issuance costs to Long-term debt	(14)
Capitalization of debt issuance costs	24
Net change in Other noncurrent assets	(12)	(12)
Accrued interest:
Payment of accrued interest on prepetition senior secured revolving credit facility	(183)
Payment of accrued interest on other prepetition secured indebtedness	(89)
Payment of accrued interest on debtor-in-possession credit facilities	(12)
Accrued interest	(284)	(284)
Accounts payable and other accrued liabilities:
Payment of hedge contract rejections	(42)
Payment of professional fees	(6)
Reinstatement of liabilities subject to compromise	38
Accrual for professional fees incurred at Emergence	13
Net change in Accounts payable and other accrued liabilities	3	3
Other current liabilities:
Issuance of equity for backstop premium	(380)
Reinstatement of liabilities subject to compromise	31
Other current liabilities	(349)	(349)
Long-term debt:
Payment of claims under prepetition secured indebtedness	(2,048)
Proceeds from secured debt	1,019
Reinstatement of PEDFA 2009B Bonds and PEDFA 2009C Bonds	130
Payment of accrued interest on prepetition senior secured revolving credit facility	26
Interest expense, debt	4
Liabilities subject to compromise prior to Emergence
Liabilities subject to compromise	(2,788)	(2,788)
Deferred income taxes:
Increase in deferred tax liabilities primarily due to estimated tax attribute reduction from the recognition of cancellation of debt income, partially offset by change in valuation allowance	206
Reinstatement of liabilities subject to compromise	77
Deferred income taxes (Note 7)	283	283
Other noncurrent liabilities:
Issuance of liability-classified warrants	35
Reinstatement of liabilities subject to compromise	25
Other noncurrent liabilities	60	60		60
Member’s equity:
Gain on settlement of liabilities subject to compromise	1,462
Other losses attributable to gain on debt discharge	(3)
Gain on debt discharge	1,459
Write-off of deferred financing cost	(46)
Professional fees	(27)
Restructuring-related compensation expense	(8)
Total reorganization items from reorganization adjustments	1,378
Interest expense incurred at Emergence	(4)
Income from reorganization adjustments before income taxes	1,374
Income tax expense	(206)
Net income from reorganization adjustments	1,168
Issuance of member’s equity in connection with rights offering	1,715
Issuance of equity for backstop premium	380
Payment to general unsecured creditors trust	186
Issuance of equity-classified warrants	8
Issuance of liability-classified warrants	(35)
Other	(6)
Total Stockholders' Equity	3,416	3,416		$ 3,416
Reorganization Adjustments \| Borrowings of $1.2 billion Under Secured Notes
Cash and Cash Equivalents:
Proceeds from secured debt	1,179
Long-term debt:
Proceeds from secured debt	1,179
Issuance of equity for backstop premium	21	21
Reorganization Adjustments \| Borrowings of $580 million Under TLB
Cash and Cash Equivalents:
Proceeds from secured debt	548
Long-term debt:
Proceeds from secured debt	548
Issuance of equity for backstop premium	32	32
Reorganization Adjustments \| Borrowings of $470 million Under TLC
Cash and Cash Equivalents:
Proceeds from secured debt	446
Long-term debt:
Proceeds from secured debt	446
Issuance of equity for backstop premium	24	24
Predecessor
Cash and Cash Equivalents:
Cash and cash equivalents	1,302	1,302
Other noncurrent assets:
Net change in Other noncurrent assets	146	146
Accrued interest:
Accrued interest	288	288
Accounts payable and other accrued liabilities:
Net change in Accounts payable and other accrued liabilities	382	382
Other current liabilities:
Other current liabilities	414	414
Liabilities subject to compromise prior to Emergence
Debt	1,555	1,555
Termination of retail contracts	447	447
Postretirement benefit obligations	305	305
Asset retirement obligations and accrued environmental costs	220	220
Other liabilities	92	92
Deferred tax liabilities	77	77
Accounts payable and accrued liabilities	51	51
Accrued interest	41	41
Liabilities subject to compromise	2,788	2,788
Reinstatement and settlements of certain Liabilities subject to compromise
Reinstatement of liabilities subject to compromise	(801)
Excess fair value ascribed to lenders participating in rights offering	(315)
Issuance of member’s equity to holders of claims under prepetition unsecured notes and PEDFA 2009A Bonds	(186)
Payment to general unsecured creditors trust	(24)
Total	(1,326)
Gain on derecognition of certain Liabilities subject to compromise	1,462
Deferred income taxes:
Deferred income taxes (Note 7)	82	82
Other noncurrent liabilities:
Other noncurrent liabilities	19	19
Member’s equity:
Total Stockholders' Equity	$ (818)	$ (818)

Postretirement Benefit Obligations - Expected Benefit Payments (Details) $ in Millions	Dec. 31, 2024 USD ($)
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
2025	$ 97
2026	94
2027	94
2028	93
2029	93
2030-2034	452
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
2025	6
2026	6
2027	5
2028	5
2029	4
2030-2034	$ 18

Basis of Presentation and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	2. Basis of Presentation and Summary of Significant Accounting Policies Basis of Presentation and Principles of Consolidation These Annual Financial Statements, which are prepared in accordance with GAAP, include: (i) the accounts of all controlled subsidiaries; (ii) elimination adjustments for intercompany transactions between controlled subsidiaries; (iii) any undivided interests in jointly owned facilities consolidated on a proportionate basis; and (iv) all adjustments considered necessary for a fair presentation of the information set forth. All adjustments are of a normal recurring nature except as otherwise disclosed. Emergence from Restructuring, Fresh Start Accounting, and Reverse Acquisition. In May 2022, TES and 71 of its subsidiaries voluntarily commenced the Restructuring under Chapter 11 of the U.S. Bankruptcy Code. TEC joined the Restructuring in December 2022. The Plan of Reorganization was approved by the requisite parties and confirmed by the bankruptcy court in late 2022, and was consummated and became effective in May 2023, when TEC, TES, and the other debtors emerged from the Restructuring. Upon commencement of the Restructuring, TES was deconsolidated from TEC for financial reporting purposes because TEC no longer controlled TES. TEC regained control of TES at Emergence, which resulted in TEC’s reconsolidation of TES. The combination was accounted for as a reverse acquisition in which TEC was the legal acquirer and TES was the accounting acquirer. Accordingly, these Annual Financial Statements are issued under the name of TEC, the legal parent of TES and accounting acquiree, but represent the continuation of the financial statements of TES, the accounting acquirer. After Emergence, TES applied fresh start accounting, which resulted in a new basis of accounting, as the Company became a new financial reporting entity. As a result of the application of fresh start accounting and the implementation of the Plan of Reorganization, our financial position and results of operations beginning after Emergence are not comparable to our financial position or results of operations prior to that date. The financial results are presented for: (i) the Predecessor periods from January 1 through May 17, 2023 (Predecessor) and the year ended December 31, 2022 (Predecessor); and (ii) the Successor periods from May 18 through December 31, 2023 (Successor) and the year ended December 31, 2024 (Successor). These Annual Financial Statements and notes hereto have been presented with a black line division to delineate the lack of comparability between the Predecessor and Successor. See Note 3 for additional information on the Restructuring and Note 4 for additional information on fresh start accounting. Consolidation of an Affiliate’s Subsidiary. In September 2022, as part of a settlement of certain matters in the Restructuring, TES exchanged preferred units in subsidiaries of Cumulus Digital for common units in Cumulus Digital. Following the consummation of the exchange and other related transactions, TES became the primary beneficiary of Cumulus Digital, a variable interest entity, due to its ability to control the activities that most significantly impacted Cumulus Digital. Accordingly, Cumulus Digital and its subsidiaries were consolidated by TES as of September 30, 2022. The difference between (i) the fair value of Cumulus Digital and its subsidiaries; and (ii) the carrying value of the preferred units immediately before the exchange resulted in a loss of $170 million presented as “Consolidation of subsidiary gain (loss)” on the Consolidated Statements of Operations for the year ended December 31, 2022 (Predecessor). Summary of Significant Accounting Policies Reclassifications. Certain amounts in the prior period financial statements were reclassified to conform to the current period’s presentation. The reclassifications did not affect operating income, net income, total assets, total liabilities, net equity, or cash flows. Use of Estimates. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Restructuring Effects. Income, expenses, gains, or losses that were incurred or realized as a direct result of the Restructuring since entering bankruptcy proceedings are presented as “Reorganization income (expense), net” on the Consolidated Statements of Operations. See Notes 3 and 4 for additional information on the Restructuring and fresh start accounting. Fair Value of Financial Instruments and Derivatives. We carry a portion of our assets and liabilities at fair value that are measured at a reporting date using an exit price (i.e., the price that would be received to sell an asset or paid to transfer a liability). An exit price may be developed under a market approach utilizing market transactions, an income approach utilizing present value techniques, or a replacement cost approach. The exit prices are disclosed according to the quality of valuation inputs under a three-tiered hierarchy comprised of: (i) Level 1 inputs that are quoted prices (unadjusted) in active markets for identical assets or liabilities; (ii) Level 2 inputs that are other than quoted prices that are directly or indirectly observable; and (iii) Level 3 inputs are unobservable inputs for assets or liabilities. The classification of an asset or liability is based on the lowest level of input significant to its fair value. Those initially classified as Level 3 are subsequently reported as Level 2 when the fair value derived from unobservable inputs is inconsequential to the overall fair value, or if corroborated market data becomes available. Those initially classified as Level 2 are subsequently reported as Level 3 if corroborated market data is no longer available. Transfers occur at the end of the reporting period. See Notes 5, 10, 14, and 15 for fair value disclosures. Operating Revenues and Revenue Recognition. Operating revenues on the Consolidated Statements of Operations are primarily comprised of items presented as: (i) “Capacity revenues;” (ii) “Energy and other revenues;” and (iii) “Unrealized gain (loss) on derivative instruments” for certain electricity contracts. Capacity revenues. Includes amounts earned from auctions in ISOs and RTOs and under bilateral contracts to provide available generation capacity that is needed to satisfy system reliability and integrity requirements. Capacity revenues are recognized ratably over the PJM Capacity Year by Talen-owned generation facilities that participate in the auctions and stand ready to deliver generated power. Capacity revenues are based on invoiced amounts corresponding directly to the value provided over a specific time interval. Energy and other revenues. Energy revenues primarily include: (i) amounts earned from sales to ISOs and RTOs for electric generation and ancillary services products that support transmission and grid operations; (ii) amounts earned for wholesale electricity sales to bilateral counterparties; and (iii) realized gains and losses on commodity derivative instruments. Sales of each electric generation and ancillary services to ISOs and RTOs represent performance obligations recognized over time based on volumes delivered or services performed at contractually agreed upon day-ahead or real-time market prices. Sales of wholesale electricity to bilateral counterparties represent performance obligations recognized over a contractually agreed period of time based on volumes delivered at the contractually agreed price. Sales of electric generation, ancillary services, and wholesale electricity to bilateral counterparties are recognized based on invoiced amounts which corresponds directly with the value provided over a specific time interval. Certain contracts constitute bundled agreements to sell energy, capacity, and (or) ancillary services. In such cases, all performance obligations are deemed to be delivered and (or) performed at the same time. Accordingly, as the timing of revenue recognition for all performance obligations is the same and occurs over a contractually agreed period of time, it is unnecessary to allocate transaction price to multiple performance obligations. Realized gains and losses on commodity derivative instruments include the settlements of financial and physical power transactions utilized for the Company’s commercial risk management objectives. Realized settlements of these derivative instruments are recognized and presented net within “Energy and other revenues” on the Consolidated Statements of Operations based on the delivery period of the underlying contract at contractually agreed prices. See “Energy Expenses” below for additional information on realized gains and losses of derivative instruments presented as “Fuel and energy purchases” on the Consolidated Statements of Operations. Other revenues primarily include: (i) Nuclear PTC revenues; and (ii) Nautilus revenues from Bitcoin mining. The Nuclear PTC program provides qualified nuclear power generation facilities with transferable credits for electricity produced and sold to an unrelated party during each tax year. These credits, which are accounted for by analogy to income-based grants under international accounting standards for government grants and disclosure of government assistance, are recognized when there is reasonable assurance that the Company will comply with the applicable conditions and that the credit will be received, which is generally over the period of production. As the credits that are generated each tax year are based on annual gross receipts and production volumes, the measurement of the credit value is estimated at each period until the final value can be determined at the end of the year, which may be different than the estimated amount. The credit value includes a five-times multiplier (up to $15 per MWh) for meeting prevailing wage requirements. Accordingly, Nuclear PTCs are recognized based on production volumes generated during the period and measured at the credit value for the tax year. See Note 6 for amounts recognized, which are presented as “Energy and other revenues” on the Consolidated Statements of Operations and “Other current assets” on the Consolidated Balance Sheets. Credits that are utilized to reduce federal income taxes payable are presented as a reduction of “Other current liabilities” on the Consolidated Balance Sheets. There have been no transfers of Nuclear PTCs to third parties during the year ended December 31, 2024 (Successor). Additional guidance expected to be issued from the U.S. Treasury and IRS may impact the credit value recognized. The primary output of Nautilus’s ordinary business activities is providing hash calculation services to solve complex cryptographic algorithms in support of blockchain mining. Nautilus is party to a mining pool arrangement to provide an unspecified amount of its available hash calculations to an unaffiliated mining pool operator. Nautilus is entitled to an enforceable right to compensation from the mining pool operator only for the duration of time over which Nautilus provides its hash calculations. In exchange for providing hash calculation services to the mining pool operator, Nautilus is entitled to consideration, whether or not the mining pool operator successfully solves a block, based on a ‘full-pay-per-share’ payout methodology. Nautilus’s only performance obligation is to provide hash calculations to the mining pool operator. If Nautilus does not provide hash calculations to the mining pool operator, no consideration is earned by Nautilus nor does Nautilus incur any penalties from the mining pool operator. The Bitcoin earned by Nautilus is all variable noncash consideration. Accordingly, Nautilus recognizes revenue that is measured at fair value using the quoted price for Bitcoin in Nautilus’s principal market at the beginning of each day (Coordinated Universal Time). Nautilus operations were suspended in October 2024. Unrealized gain (loss) on derivative instruments. Includes unrealized gains and losses resulting from changes in the fair value of certain power contracts that qualify as derivative instruments. See “Derivative Instruments” below for the recognition criteria of unrealized gains and losses on commodity derivative instruments. See “Energy Expenses” below for additional information on unrealized gains and losses of derivative instruments presented as “Energy Expenses” on the Consolidated Statements of Operations. See Note 6 for additional information on revenue. Energy Expenses. Energy expenses on the Consolidated Statements of Operations are primarily comprised of items presented as: (i) “Fuel and energy purchases;” (ii) “Nuclear fuel amortization;” and (iii) “Unrealized gain (loss) on derivative instruments” for certain commodity purchase contracts. Fuel and energy purchases. Primarily includes: (i) fuel costs; (ii) environmental product costs; and (iii) realized gain (loss) on commodity derivative instruments. Fuel costs include the costs incurred by Talen-owned generation facilities for the conversion of natural gas, coal, and (or) oil products to electricity. Fuel for electric generation from natural gas purchases are recognized at the agreed price for natural gas delivered to the applicable generation facility over a contractually agreed period of time. Fuel for electric generation from coal and oil product inventories are recognized at the applicable weighted average inventory cost of volumes consumed. Environmental product costs primarily include RGGIs and other emission product compliance costs that are mandated by certain states. The estimated cost of compliance is accrued at the time an obligation under the applicable terms of each state's environmental compliance program arises. Realized gains and losses on commodity derivative instruments primarily include the settlements of financial and physical fuel contracts utilized for the Company’s commercial risk management objectives. Realized settlements of these derivative instruments are recognized and presented net within “Fuel and energy purchases” on the Consolidated Statements of Operations based on the delivery period of the underlying contract at contractually agreed prices. See “Operating Revenues and Revenue Recognition” above for additional information on realized gains and losses on derivative instruments presented as “Energy and other revenues” on the Consolidated Statements of Operations. Nuclear fuel amortization. Nuclear fuel-related costs, including procurement of uranium, conversion, enrichment, fabrication and assemblies, are capitalized and presented as “Property, plant and equipment, net” on the Consolidated Balance Sheets and presented as a cash outflow within the investing activities section on the Consolidated Statements of Cash Flows. Such costs are amortized as the fuel is consumed using the units-of-production method and presented as “Nuclear fuel amortization” on the Consolidated Statements of Operations. Unrealized gain (loss) on derivative instruments. Includes unrealized gains and losses resulting from changes in the fair value of certain fuel contracts and environmental product contracts that qualify as derivative instruments. See “Derivative Instruments” below for the recognition criteria of unrealized gains and losses on commodity derivative instruments. See “Operating Revenues and Revenue Recognition” above for additional information on unrealized gains and losses of derivative instruments presented as “Operating Revenues” on the Consolidated Statements of Operations. Derivative Instruments. The fair value of derivative contracts required to be measured at fair value are presented as “Derivative instruments” within assets or liabilities on the Consolidated Balance Sheets. The primary type of derivative instruments utilized are commodity derivatives. Commodity derivative contracts are valued using inputs and assumptions such as contractual volumes, delivery location, forward commodity prices, commodity price volatility, discount rates, and credit worthiness of counterparties. For derivatives that trade in liquid markets, such as generic forwards, swaps, and options, the inputs and assumptions are generally observable. Such instruments are categorized in Level 2. In most instances, master netting agreements govern derivative transactions between parties and contain certain provisions for setoff rights. The fair value of derivative instruments is presented net of setoff rights and cash collateral deposits. The fair value of commercial contracts that are not subject to netting and (or) collateral provisions is presented gross. Prior to Emergence, the fair value of derivative instruments presented on the Consolidated Balance Sheets was presented gross of setoff rights and cash collateral deposits exchanged between parties under such arrangements. Unrealized gains or losses associated with a derivative instrument that economically hedges certain risks but where qualified cash flow hedge accounting is not elected or not met are presented on the Consolidated Statements of Operations in the period when such gains or losses arise. As there are no derivatives where qualified hedge accounting has been elected, changes in the fair value of commodity derivatives are presented as “Unrealized gain (loss) on derivative instruments,” as a component of either “Operating Revenues” or “Energy Expenses” on the Consolidated Statements of Operations in a manner consistent with the presentation of net realized gains and losses. See “Operating Revenues” and “Energy Expenses” above for a discussion of net realized gains and losses on commodity derivatives. The cumulative net gains or losses for interest rate contracts are presented as “Interest expense and other finance charges” on the Consolidated Statements of Operations. See Notes 5 and 14 for additional information on the presentation of derivative contracts and fair value measurements. Operation, Maintenance and Development. The costs of removal, repairs, maintenance, and other operating costs, pre-commercial development activities, and salaries and benefits for operations personnel that each do not meet capitalization criteria are recognized as an expense when incurred. Materials and supplies inventories are recognized as an expense at the weighted average cost of materials consumed as they are used for repairs and maintenance. Costs for pre-commercial development stages of certain projects that are not capitalized as “Property, plant and equipment, net” on the Consolidated Balance Sheets and recurring operational and maintenance activities are each presented as “Operation, maintenance and development” on the Consolidated Statements of Operations. Development expenses incurred are primarily for pre-commercial activities at Nautilus and hyperscale construction activities at Cumulus Digital. Stock-Based Compensation. TEC grants performance stock units (“PSUs”) and restricted stock units (“RSUs”) to certain employees and non-employee directors. The fair value of PSUs is estimated on the grant date utilizing a Monte Carlo Valuation Model, which contains significant unobservable inputs that are believed to be consistent with those used by principal market participants. The fair value of RSUs is derived from the closing price of TEC common stock at the grant date. Forfeitures are recognized as they occur. Unvested PSUs and RSUs are entitled to dividends or dividend equivalents, which are accrued and distributed to award recipients at the time such awards vest. Dividends and dividend equivalents are subject to the same vesting and forfeiture provisions as the underlying awards. Stock-based compensation expense is recognized for both graded and cliff vesting awards on a straight-line basis over the requisite service period for the entire award. Stock-based compensation expense is presented as “General and administrative” on the Consolidated Statements of Operations. See Note 16 for additional information on stock-based compensation. Income Taxes. TEC and its subsidiaries file a consolidated U.S. federal income tax return. Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying values of existing assets and liabilities and their respective tax basis, tax credits and NOL carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities due to a change in tax rates is recognized as income in the period that includes the enactment date. Valuation allowances are recognized to reduce deferred tax assets to the extent necessary to result in an amount that is more likely than not to be realized. Disproportionate income tax effects are removed from AOCI when the circumstance upon which they are premised ceases to exist. The financial statement effect of a tax position is recognized when it is more-likely-than-not, based on the technical merits, that the position will be sustained upon examination. A tax position that meets the more-likely-than-not recognition threshold is measured as the largest amount of tax benefit that is greater than 50% likely of being realized upon ultimate settlement with a taxing authority. A previously recognized tax position is reversed in the first period in which it is no longer more-likely-than-not that the tax position would be sustained upon examination. Interest and penalties from tax uncertainties are presented as “Income tax benefit (expense)” on the Consolidated Statements of Operations. See Note 7 for additional information on income taxes. Loss Contingencies. Potential losses are accrued when: (i) information is available that indicates it is probable (i.e., likely to occur) that a loss has been incurred, given the likelihood of the uncertain future events; and (ii) the amount of the loss can be reasonably estimated. We continuously assess potential loss contingencies for environmental remediation, litigation claims, regulatory penalties and other events. Loss contingencies are discounted when appropriate. Legal costs are expensed as incurred. See Note 12 for additional information. Concentrations of Credit Risk. Concentrations of credit risk exist primarily within cash and cash equivalents, receivables, and commodity derivative assets. Cash and cash equivalents are generally held in accounts where the amounts deposited exceed the maximum deposit insurance provided by the Federal Deposit Insurance Corporation. Cash and cash equivalents and restricted cash balances are primarily deposited in accounts with major financial institutions with investment grade credit ratings. In certain instances, funds are invested in highly liquid U.S. Treasury securities or other obligations with original maturities of less than 90 days that are issued by or guaranteed by the U.S. Government. Concentrations of credit risk for receivables are primarily attributable to entities that reimburse Talen for certain capital expenditures and operating costs associated with jointly owned facilities. Concentrations of credit risk for commodity derivative assets are primarily attributable to unaffiliated investment grade counterparties which engage in energy marketing activities with Talen Energy Marketing. See Note 5 for additional information on concentrations of credit risk. Cash and Cash Equivalents. Bank deposits, liquid investments, and other similar assets with original maturities of three months or less. Bank deposits, commodity exchange deposits, liquid investments, and other similar assets with original maturities of three months or less that are restricted by agreement are presented as “Restricted cash and cash equivalents” on the Consolidated Balance Sheets. See Note 19 for additional information. Accounts Receivable. Receivables primarily consist of amounts due from customers or other contract counterparties, net of any collection allowances. Uncollected receivables greater than 30 days past due are assessed for collectability based on a variety of factors that include, but are not limited to, customer credit worthiness, duration receivables are outstanding, and (or) historical collection experience. Management continuously assesses and considers current economic trends that might impact the amount of future credit losses. Additionally, if it becomes known that a specific customer may have the inability to settle its obligation that is not yet past due, such receivables are assessed for collectability. If these assessments indicate a receivable collection is remote, its carrying value is reduced through an allowance for doubtful accounts measured at management’s best estimate, and a charge is presented on the Consolidated Statements of Operations. If any portion of the original carrying value of the receivable is recovered, the allowance and the associated charge are reversed in the period of collection. Inventory. Inventory consists of fuel for generation (primarily coal and fuel oil), materials and supplies, and environmental products each of which are valued at the lower of weighted average cost or net realizable value. See Note 8 for additional information on inventory. Variable Interest Entities. The primary beneficiary (a controlling financial interest) of a VIE is required to consolidate the VIE when it has both: (i) the power to direct the activities that most significantly impact the entity’s economic performance; and (ii) the obligation to absorb losses or receive benefits from the entity that could potentially be significant to the VIE. Talen consolidates a VIE when it is determined that it is the primary beneficiary of the VIE. Investments in entities in which Talen has the ability to exercise significant influence but does not have a controlling financial interest are accounted for under the equity method. Investments in Debt and Equity Securities. The NDT holds investments in available-for-sale debt securities and equity securities, which are carried at fair value and presented as “Nuclear decommissioning trust funds” on the Consolidated Balance Sheets. Unrealized gains and losses, net of income tax, on available-for-sale debt securities are presented as “Other Comprehensive Income (Loss)” on the Consolidated Statements of Comprehensive Income in the period when such gains and losses arise. Realized gains and losses on available-for-sale debt securities are transferred from AOCI to “Nuclear decommissioning trust funds gain (loss), net” on the Consolidated Statements of Operations in the period when the sale of the security occurs. The specific identification method is used to calculate realized gains and losses on debt and equity securities. If an available-for-sale debt security's fair value declines below cost and the decline is determined to be other-than-temporary, the unrealized loss is recognized on the Consolidated Statements of Comprehensive Income in the period when such determination arises. Unrealized gains and losses and realized gains and losses on equity securities are presented as “Nuclear decommissioning trust funds gain (loss), net” on the Consolidated Statements of Operations in the period when such gains or losses arise. See Notes 9 and 14 for additional information on investments in debt and equity securities. Property, Plant and Equipment. Expenditures for land, the construction of facilities, the addition or refurbishment of major equipment, and commercially viable new development projects are capitalized at cost. Such capitalized amounts include interest costs, where appropriate. Facilities, land, and other equipment acquired in a business combination is recognized at fair value. In each case, such amounts are presented as “Property, plant and equipment, net” on the Consolidated Balance Sheets. Reductions in the carrying value of PP&E are accumulated over the estimated useful life of each depreciable unit using straight-line or group depreciation methods, where appropriate. Such periodic reduction is presented as a charge to “Depreciation, amortization and accretion” on the Consolidated Statements of Operations. Generally, upon normal retirement of PP&E under the group depreciation method, the costs of such assets are retired against accumulated depreciation in the period of the retirement and no gain or loss is recognized. Any remaining carrying value of PP&E at its retirement date that depreciated under the straight-line depreciation method is presented as a loss within “Other operating income (expense), net” on the Consolidated Statements of Operations. Any remaining carrying value of PP&E at its sale date and any proceeds from the disposition are presented as a gain or loss net on the Consolidated Statements of Operations. Expenditures for intangible assets such as contractual rights, software and licenses are capitalized at cost and are presented as “Property, plant and equipment, net” on the Consolidated Balance Sheets. Reductions in the carrying value of intangible assets with finite useful lives are accumulated over the estimated useful life of each intangible asset using an amortization pattern which reflects the economic benefits of the intangible asset. Such periodic reduction is presented as a charge to “Depreciation, amortization and accretion” on the Consolidated Statements of Operations. See “Impairments” below for additional information regarding impairments on the carrying values of PP&E. See Note 10 for additional information on PP&E. Impairments. PP&E used in operations are assessed for impairment whenever changes in facts and circumstances indicate the carrying value of the asset group may not be recoverable. Indicators of impairment may include changes in the economic environment, negative financial trends, physical damage to assets or decisions of management regarding strategic initiatives. Where applicable, individual assets are grouped for impairment purposes at the lowest level for which there are identifiable cash flows that are largely independent of the cash flows of other assets and liabilities. If there is an indication the carrying value of an asset group may not be recovered, management reviews the expected future cash flows of the asset group. If the sum of the undiscounted pre-tax cash flows is less than the carrying value of the asset group, the asset group is written down to its estimated fair value. Impairment charges are presented as “Impairments” on the Consolidated Statements of Operations in the period in which the impairment condition arises. If facts and circumstances indicate that the carrying value of an asset under construction will have no future economic benefit, such amounts are presented on the Consolidated Statements of Operations in the period in which such projects are abandoned, canceled, or management otherwise determines the costs to be unrecoverable. Fair value may be determined by a variety of valuation methods including third-party appraisals, market prices of similar assets, and present value techniques. However, as there is generally a lack of quoted market prices for long-lived assets, the fair value of impaired assets is typically determined based on the present values of expected future cash flows using discount rates that are believed to be consistent with those used by principal market participants. The estimated cash flows and related fair value computations consider all available evidence at the date of the review, such as estimated future generation volumes, forward capacity and commodity prices, energy prices, operating costs, capital expenditures, and environmental costs. See Note 10 for information on impairments. Asset Retirement Obligations. A liability for an ARO or conditional ARO exists when a legal obligation arises from laws, regulations or other contractual requirements for the retirement of tangible long-lived assets. When an ARO liability is incurred, which is typically at asset construction or through assumption of the liability in connection with a business combination, it is initially recognized at fair value. Fair value measurements are estimated under a present value technique and are discounted using a credit-adjusted risk-free rate. Additionally, given the inherent uncertainty in estimating the amount of cash flows to settle an ARO liability or its settlement date, fair value estimates include a market risk premium and a range of possible cash flow outcomes, where applicable. At the initial recognition, the effects on the Consolidated Balance Sheets include: (i) an increase to “Asset retirement obligations and accrued environmental costs” for the portion of ARO to be settled after one year and (or) “Other current liabilities” for the portion of the ARO to be settled within one year; and (ii) an offsetting increase to “Property, plant and equipment, net” for the asset retirement capitalized cost. Estimated future ARO cash expenditures and settlement dates are reviewed periodically to identify any required amendments to the carrying value of each ARO liability. ARO liabilities increase over a period of time through the recognition of accretion expense to recognize changes in the obligation due to the passage of time. The asset retirement capitalized cost is depreciated at a rate consistent with the useful life of the associated long-lived asset. The depreciation of the asset retirement capitalized cost and the accretion of the ARO liability are each presented as “Depreciation, amortization and accretion” on the Consolidated Statements of Operations. An ARO liability amendment associated with a long-lived asset that is not fully impaired or depreciated is recognized through an adjustment to the ARO liability and the asset retirement capitalized cost. Any revision to the asset retirement capitalized cost is generally depreciated over the remaining life of the associated long-lived asset. An ARO liability amendment associated with a fully impaired or depreciated asset is presented as “Other operating income (expense), net” on the Consolidated Statements of Operations. At settlement, a gain or loss will arise if the cash expenditures to settle the ARO liabilities are different than the carrying values. Such gains or losses are presented as “Other operating income (expense), net” on the Consolidated Statements of Operations. A conditional ARO refers to an entity’s legal obligation to perform an asset retirement activity in which the timing or method of settlement is conditional on a future event that may or may not be within the entity’s control, including legal or regulatory requirements. There may also be instances when there is no available information regarding the ultimate ARO settlement timing or the fair value of the obligation may not be reasonably estimable. If sufficient information becomes available to reasonably estimate the fair value of the liability for an ARO or a conditional ARO, a liability is recognized in the period in which it is determined. See Note 11 for additional information on AROs. Contingencies. Management continuously assesses potential loss contingencies for environmental remediation, litigation claims, regulatory penalties and other events. Potential losses are accrued when: (i) information is available that indicates it is probable (i.e., likely to occur) that a loss has been incurred, given the likelihood of the uncertain future events; and (ii) the amount of the loss can be reasonably estimated. Loss contingencies are recognized at management's best estimate, which may be discounted, where appropriate. Loss contingencies exclude estimates for any legal fees, which are recognized as incurred when the legal services are performed. See Note 12 for additional information on loss contingencies. Business interruption insurance proceeds are considered gain contingencies and not recognized until realized. Debt. Proceeds received on the issuance of new term loans, secured notes, unsecured notes, bonds, and similar indebtedness are presented as “Long-term debt” or “Long-term debt, due within one year” on the Consolidated Balance Sheets. Interest incurred as paid-in-kind, whether accrued or capitalized as additional principal are presented as “Long-term debt” with the associated outstanding amounts of indebtedness. Costs incurred to issue new indebtedness and any original issuance discounts or premiums are deferred at issuance on the Consolidated Balance Sheets and presented together with the associated outstanding principal amounts of indebtedness. Interest accrues on outstanding principal amounts of indebtedness based on contractually determined rates during each period. Costs incurred for the issuance of indebtedness and any original issuance discounts or premiums are subsequently amortized through the expected maturity date of the associated indebtedness under the effective interest rate method and are presented as “Interest expense and other finance charges” on the Consolidated Statements of Operations. Gains and losses on the: (i) early redemption of indebtedness; or (ii) early termination and (or) reduction of revolving credit facility committed capacity are presented as a gain or loss on the Consolidated Statements of Operations. Such amounts include the proportional derecognition of any deferred financing costs, fees, discounts, and (or) premiums associated with the indebtedness. Direct cash borrowings under secured lines of credit, revolving credit facilities, and similar indebtedness are presented as a current liability on the Consolidated Balance Sheets. Costs incurred to issue new arrangements are deferred and presented as “Other current assets” or “Other noncurrent assets” on the Consolidated Balance Sheets. Interest accrues on direct cash borrowings and LCs based on contractually determined rates during each period. Costs incurred to issue new arrangements are subsequently amortized through the expected expiration of the associated arrangement under the straight-line method. Commitment fees on available but unused credit facility capacity are expensed as incurred. Such costs are presented as “Interest expense and other finance charges” on the Consolidated Statements of Operations. See Note 13 for additional information on debt. Postretirement Benefit Obligations. Certain Talen subsidiaries sponsor various defined benefit pension plans and other postretirement benefit plans. Gains and losses, net of income tax, that arise and are not a component of net periodic defined benefit costs are presented as “Other Comprehensive Income (Loss)” on the Consolidated Statements of Comprehensive Income. Following Emergence, actuarial gains and losses in excess of the greater of 10% of the plan's projected benefit obligation or the market-related value of plan assets are amortized over (i) the expected average remaining service period of active plan participants for active plans; or (ii) the average future remaining lifetime of the plan participants of frozen plans. Prior to Emergence, Talen used an accelerated amortization method for the recognition of gains and losses for defined benefit pension plans: (i) actuarial gains and losses in excess of 30% of the plan's projected benefit obligation are amortized on a straight-line basis over one-half of the expected average remaining service of active plan participants; and (ii) actuarial gains and losses in excess of 10% of the greater of the plan's projected benefit obligation or the market-related value of plan assets and less than 30% of the plan's projected benefit obligation are amortized on a straight-line basis over the expected average remaining service period of active plan participants. Following Emergence, a spot rate curve that represents a portfolio of high-quality corporate bonds is used to develop the discount rate utilized to measure the projected benefit obligations and service costs for benefit plans. Prior to Emergence, a bond matching methodology was utilized, based on a specific portfolio of bonds that closely match the overall cash flow timing and duration of the benefit plans. Talen is obligated to provide health care benefits under the Coal Act and pneumoconiosis (black lung) benefits under the Black Lung Act for retired miners and eligible beneficiaries. Benefits are funded from a Voluntary Employees’ Benefit Association (“VEBA”) trust and a trust maintained under certain federal and state black lung legislation. Shortfalls in funded status of the plans are assessed as contingent liabilities. As such, Talen recognizes funding shortfalls on its balance sheet, where applicable, if benefit obligations of either plan exceed the fair value of available trust assets. See Note 15 for additional information on the plans and the accounting for defined benefits. Treasury Stock and Retirement of Treasury Shares. Share repurchases are accounted for under the cost method, which recognizes the entire cost of the acquired stock, including transaction costs and excise tax, as a reduction in additional paid-in-capital and are presented as “Treasury stock” on the Consolidated Balance Sheets. Share repurchases are recognized on a trade date basis when we are contractually obligated to purchase the shares. Treasury shares are retired on the settlement date of the transaction. At retirement, the common stock balance is reduced for the par value of the shares. The excess of the acquisition cost of repurchased shares over the par value is recognized in additional paid-in capital (up to the amount credited to additional paid-in capital upon original issuance of the shares), with any remaining cost deducted from retained earnings. Recently Adopted Accounting Pronouncements ASU 2023-07. In November 2023, the Financial Accounting Standards Board (the “FASB”) issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. This ASU requires enhanced disclosures about significant segment expenses. The ASU is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted. The Company adopted the fiscal year disclosure requirements for this ASU beginning January 1, 2024, and will adopt interim period disclosure requirements beginning January 1, 2025. Recent Accounting Pronouncements Not Yet Adopted ASU 2023-09. In December 2023, the FASB issued ASU 2023-09 Income Taxes (Topic 740): Improvements to Income Tax Disclosures. This ASU requires annual disclosures for specific categories in the rate reconciliation and additional information for reconciling items that meet a quantitative threshold. The ASU is effective for fiscal years beginning after December 15, 2024. Early adoption is permitted for annual financial statements that have not yet been issued. The Company is evaluating the disclosure impact of this ASU and expects to adopt it in the required period. ASU 2024-03. In November 2024, the FASB issued ASU 2024-03, Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses. This ASU requires public companies to disclose, in the notes to financial statements, specified information about certain costs and expenses at each interim and annual reporting period. This ASU is effective for annual reporting periods beginning after December 15, 2026. Early adoption is permitted. The Company is evaluating the disclosure impact of this ASU and expects to adopt it in the required period.

Fresh Start Accounting - Reorganization Income (Expense), net (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Reorganizations [Abstract]
Backstop premium	$ (70)			$ (310)
Gain on debt discharge	1,459			0
Gain (loss) on revaluation adjustments	(460)			0
Professional fees	(56)			(210)
Make-whole premiums and accrued interest on certain indebtedness	(21)			(183)
Professional fees incurred to obtain the debtor-in-possession credit facilities	0			(70)
Write-off of deferred financing cost and original issue discount	(46)			(30)
Other	(7)			(9)
Reorganization Items	$ 799	$ 0	$ 0	$ (812)

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	12. Commitments and Contingencies Legal, Regulatory, and Environmental Matters We are regularly subject to various legal, regulatory, and environmental matters in connection with our business. While we believe we have meritorious positions and will continue to vigorously defend our positions in these matters, we may not be successful in our efforts, and we cannot predict the effect of an adverse outcome of any such matter. If an unfavorable outcome is probable and can be reasonably estimated, a liability is recognized. In the event of an unfavorable outcome, the liability may be in excess of amounts currently accrued. Because of the inherently unpredictable nature of legal, regulatory, and environmental matters and the wide range of potential outcomes for any such matter, no estimate of the possible losses in excess of amounts accrued, if any, can be made at this time regarding any matter specifically described below. As a result, additional losses actually incurred in excess of amounts accrued could be substantial. Unless otherwise disclosed below, we are unable to predict the outcome of any matter discussed below or reasonably estimate the amount of any associated costs and (or) potential liabilities. Additionally, it is possible that the outcome of any such matter, including market modifications, could materially impact our business, financial condition, results of operations, cash flows, and (or) liquidity. Legal Matters We are involved in various legal and administrative proceedings, investigations, claims, and litigation from time to time in the course of our business. Such matters may include, but are not limited to, those relating to employment and benefits, commercial disputes, personal injury, property damage, regulatory matters, environmental matters, and various other claims for injuries and (or) damages. While we believe we have meritorious positions and will continue to appropriately respond to all legal matters, because of the inherently unpredictable nature of legal proceedings, there is a wide range of potential outcomes for any such matter. ERCOT Weather Event (Winter Storm Uri) Lawsuits. In connection with the ERCOT Sale (see Note 20 for additional information), the Company retained certain potential liabilities relating to claims filed from 2021 onward against its former Texas subsidiaries seeking unspecified damages for alleged losses caused by the defendants’ failure to provide sufficient power to the grid during Winter Storm Uri. The claims also allege similar liability against numerous other ERCOT power market participants. In December 2023, five multi-district litigation (“MDL”) bellwether lawsuits, which were selected by the MDL court as representative of all 58 cases filed in the Uri litigation, were dismissed by the MDL court, a ruling subsequently upheld by the Texas First Court of Appeals. On January 31 and February 3, 2025, the plaintiffs (in two groups) filed for mandamus relief in the Texas Supreme Court, seeking to overturn the lower courts. If affirmed by the Texas Supreme Court, Talen expects the dismissal ruling to apply broadly to all Uri cases against Talen’s former subsidiaries. Pursuant to the Plan of Reorganization, Talen’s maximum potential damages on prepetition Uri claims are expressly limited to payments from Talen’s insurers. However, claims filed after the Restructuring by plaintiffs who did not receive effective notice of the Restructuring, if any, may not be subject to the limitations in the Plan of Reorganization. Spent Nuclear Fuel Litigation. Federal law requires the U.S. government to provide for the permanent disposal of commercial SNF, but the government has not yet done so. Until May 2014, the Department of Energy required nuclear generation facility operators to contribute to a fund intended to pay for the transportation and disposal of SNF, and Talen cannot predict if or when the government will reinstate any such fee in the future. In May 2023, an existing settlement agreement between Susquehanna and the U.S. government was extended through the end of 2025. The settlement agreement requires the government to reimburse Susquehanna for certain SNF storage costs through 2025 and requires Susquehanna to waive certain claims against the government relating to temporary SNF storage. As of December 31, 2024 (Successor), the Company has an accrued receivable of $14 million related to such reimbursements. During the period from May 18 through December 31, 2023 (Successor) and the year ended December 31, 2022 (Predecessor), Susquehanna received reimbursements of $24 million and $7 million for such costs. No assurance can be provided that this arrangement will be extended beyond 2025. Regulatory Matters We are subject to regulation by federal and state agencies and other bodies that exercise regulatory authority in the various regions where we conduct business, including but not limited to FERC; the Department of Energy; the NRC; NERC; the Federal Communications Commission; and state public utility commissions. In addition, the RTOs and ISOs in the regions in which we conduct business inherently have complex rules that are intended to balance the interests of market stakeholders. Proposed market structure modifications may lead to disputes among stakeholders that might not be resolved for a period of time as a result of regulatory and (or) legal proceedings. Accordingly, we are subject to uncertainty with respect to: (i) new or amended regulations issued by regulatory agencies; and (ii) changes in market design, tariff structure, capacity auctions, and (or) pricing rules. PJM Capacity Market Reform. In June 2023, FERC accepted a request by PJM to delay certain PJM Base Residual Auctions in order for PJM to propose market reforms. PJM filed its market reform proposals with FERC in October 2023. In early 2024, FERC accepted portions of PJM’s proposed market changes. PJM held the PJM BRA for the 2025/2026 PJM Capacity Year in July 2024 which incorporated the FERC accepted changes. The PJM BRAs for the 2026/2027, 2027/2028, and 2028/2029 PJM Capacity Years were previously scheduled for December 2024, June 2025 (later changed to July 2025), and December 2025, respectively; however in September 2024, the Sierra Club and other organizations filed a complaint at FERC challenging PJM’s rules establishing must-offer exceptions for PJM BRA participation by RMR resources and seeking to delay the 2026/2027 PJM BRA pending resolution of its complaint. In October 2024, PJM announced it had concerns about FERC considering the Sierra Club’s complaints about RMR resources in isolation and therefore intended to file a Section 205 proceeding under the Federal Power Act seeking FERC’s approval of to-be-determined market reforms, including but not limited to potential revisions to the treatment of RMR resources. As a result, in October 2024 PJM formally requested that FERC approve six-month delays in the PJM BRAs for the 2026/2027, 2027/2028, 2028/2029, and 2029/2030 PJM Capacity Years and in November 2024, FERC approved the auction delays. The planning parameters for the 2026/2027 PJM BRA are expected in March 2025. Talen can provide no assurance that the four scheduled auctions will be held as scheduled or at all. A series of filings aimed at reforming the PJM capacity market were filed at FERC. In November 2024, the Joint Consumer Advocates, comprised of consumer advocacy groups and government entities from Illinois, Maryland, New Jersey, Ohio, and the District of Columbia filed a complaint against PJM asking FERC to find that PJM’s existing capacity market rules are unjust and unreasonable and issue an order requiring certain short-term and longer-term changes to PJM’s capacity market rules. In response, PJM made two FERC filings in December 2024 to address what they perceive as capacity market design issues (the “PJM Capacity Market 205 proceeding”). PJM proposed to retain the dual fuel combustion turbine as the reference resource and to implement a uniform non-performance charge throughout the RTO for the 2026/2027 and 2027/2028 delivery years, and to administratively include RMR units that meet certain criteria as price takers in the capacity auctions for the next two delivery years and will not assess penalties or pay bonuses to these RMR units. If approved, under PJM’s proposal, Talen’s Brandon Shores and H.A. Wagner plants may meet the criteria for RMR inclusion in the capacity auctions. PJM’s filing also clarifies that being excused from being required to offer into the capacity market is no defense to exercising market power by electing not to offer. Further, PJM proposed to make changes to the capacity market mitigation rules. This proposal will eliminate the must-offer exception for intermittent and limited duration resources that are eligible to participate in the capacity market and will allow market sellers to incorporate a risk component in their capacity market offers. Following the above filings, in December 2024, the Pennsylvania Governor filed a complaint against PJM at FERC to address alleged elevated costs to consumers from the PJM capacity market in the 2026/2027 and 2027/2028 delivery years. Among other things, the Governor’s complaint proposed to lower the capacity price cap and reopen the closed interconnection queue to get new projects online. In January 2025, the Governor filed a motion to consolidate his complaint with the Joint Consumer Advocates complaint and two PJM filings referenced above. On January 28, 2025, the Governor and PJM announced they had reached an agreement to resolve the Governor’s complaint. That agreement would impose a collar on the capacity prices in the 2026/2027 and 2027/2028 BRAs, with a minimum capacity price of $175/Megawatt-day (“MWd”) and a maximum price of $325/MWd. On February 14, 2025, FERC accepted PJM’s proposals in the PJM Capacity Market 205 proceeding and as a result, the changes to the BRA parameters described above as part of that proceeding will be adopted for the 2026/2027 and 2027/2028 delivery years. Also on February 14, 2025, as a result of the agreement with PJM to collar the BRA results for the next two auction the Governor withdrew his complaints from FERC. On February 20, 2025, PJM initiated a new Section 205 proceeding seeking FERC’s approval of a settlement that will revise the relevant auction parameters and impose the capacity price collar agreed to with the Governor. The filing seeks expedited treatment intended to maintain the current auction schedule. At this time, it is unknown whether the collar arrangement will be approved by FERC or whether the auction schedule will remain unchanged. Talen filed comments in support of this proposal on February 24, 2025. On February 20, 2025, FERC initiated a technical conference docket to consider broad resource adequacy issues across all RTOs, with the initial proceedings to take place on June 4 and 5, 2025. The Company intends to intervene in the new technical conference docket and participate in those proceedings. Environmental Matters Extensive federal, state, and local environmental laws and regulations are applicable to our business, including those related to air emissions, water discharges, and hazardous substances and solid waste management. From time to time, in the ordinary course of our business, Talen may be: (i) subject to environmental remediation work at its facilities; (ii) involved in other environmental matters; or (iii) become subject to other, new or revised environmental statutes, regulations, or requirements. It may be necessary for us to modify, curtail, replace, or cease operation of certain facilities or performance of certain operations to comply with statutes, regulations, and other requirements imposed by regulatory bodies, courts, or environmental groups. We may incur significant costs to comply with these requirements, including increased capital expenditures or operation and maintenance expenses, monetary fines, remediation costs, penalties, or other restrictions. Legal challenges to environmental rules or permits add to the uncertainty of estimating future compliance costs. In addition, in January 2025, President Trump issued executive orders directing the heads of all federal agencies to identify and begin the processes to suspend, revise, or rescind all agency actions, including existing regulations, that are unduly burdensome on the identification, development, or use of domestic energy resources. Consequently, future implementation and enforcement of these rules remains uncertain at this time. Further, costs may increase significantly if the requirements or scope of environmental laws or regulations, or similar rules, are expanded or changed. EPA CSAPR and Nitrogen Oxides (“NOx”) Requirements. Coal-fired generation facilities, including those in which Talen has ownership, have been the subject of EPA regulations and efforts by certain states and other parties to strengthen applicable NOx emission limits under the Clean Air Act. In 2015, the EPA’s 2015 revision to the 8-hour ozone National Ambient Air Quality Standards for ground-level ozone to 70 parts per billion (the “EPA 2015 Ozone Standard”) was issued, which triggered updates to state-specific compliance requirements as well as provisions that are intended to limit cross-state emissions. In June 2023, the EPA published a rule in connection with the EPA 2015 Ozone Standard updating the EPA CSAPR ozone season NOx allowance trading program for 2023 and beyond (“Good Neighbor Plan”). Talen’s facilities in Maryland, Pennsylvania, and New Jersey are subject to the new rule; however, the entire rule has been challenged by multiple parties. The Good Neighbor Plan was stayed in its entirety by the U.S. Supreme Court in June 2024 pending a complete review of the rule by the D.C. Circuit Court of Appeals. In November 2024, the EPA issued an interim final rule indicating it plans to provide NOx allocations and budgets from the previously applicable and less restrictive Revised CSAPR Update rule until the Good Neighbor Plan matter is resolved. In February 2025, the D.C. Circuit Court of Appeals denied the EPA’s motion requesting the Good Neighbor Plan litigation be held in abeyance for 60 days and ordered the parties to complete supplemental briefing in March 2025. As a result, future implementation and enforcement of the Good Neighbor Plan remains uncertain at this time. EPA MATS Rule. In May 2024, the EPA published a rule that requires coal-fired generation facilities to reduce particulate matter emissions by the middle of 2027 (or 2028, if an extension is approved). Colstrip is not expected to meet the new particulate matter standard without substantial upgrades to its control equipment. As a result, Talen Montana and the other Colstrip co-owners face the decision either to invest in new cost-prohibitive control equipment or retire the Colstrip facility. Such decision must be evaluated in conjunction with compliance requirements under the May 2024 EPA GHG Rule due to timing and costs. Challenges to the EPA MATS Rule have been filed in the D.C. Circuit Court of Appeals, including by Talen and 23 states. After motions to stay the EPA MATS Rule during the pendency of the litigation were denied by the D.C. Circuit Court of Appeals, Talen and other parties filed emergency stay request applications with the U.S. Supreme Court in September 2024, which were denied in October 2024. The appeal on the merits of the new rule remains pending in the D.C. Circuit Court of Appeals. In February 2025, the D.C. Circuit Court of Appeals granted the EPA’s unopposed motion to hold the MATS litigation in abeyance for 90 days. No assurance can be provided as to when the challenges to the EPA MATS Rule will be resolved or whether such challenges will be resolved in the Company’s favor. As the timeline for compliance with the new standards is accelerated and must be considered in tandem with the new EPA GHG Rule, which is also subject to ongoing legal challenges, it is possible the Company will need to make operating decisions about the future of Colstrip before the Company has clarity about the outcome of the litigation. EPA GHG Rule. In May 2024, the EPA published a rule that establishes carbon dioxide limits for new electric generating units (“EGUs”) and GHG guidelines for certain existing EGUs. Under the guidelines, if existing coal-fired EGUs operate beyond 2031, GHG reductions, such as those achieved by the addition of carbon capture and sequestration (“CCS”), are required to be implemented by the end of 2031. Colstrip is not expected to meet the new rules without substantial technology upgrades and pipeline infrastructure build-out. As a result, Talen Montana and the other Colstrip co-owners face the decision either to invest in new cost-prohibitive controls (e.g., CCS technology) or retire the Colstrip facility by the end of 2031. Such decision must be evaluated in conjunction with compliance requirements under the May 2024 EPA MATS Rule. Petitions have been filed in the D.C. Circuit Court of Appeals, including by coalitions representing 27 states and an ad hoc coalition of power producers of which Talen is a member, requesting a review of the EPA GHG Rule. Stay motions were denied by the D.C. Circuit Court of Appeals in July 2024 and the U.S. Supreme Court in October 2024. Appeals of the EPA GHG Rule remain pending in the D.C. Circuit Court of Appeals. In February 2025, the D.C. Circuit Court of Appeals granted the EPA’s unopposed motion to hold the litigation in abeyance for 60 days. No assurance can be provided as to when the challenges to the EPA GHG Rule will be resolved or whether such challenges will be resolved in the Company’s favor. The EPA has also stated its intent to develop GHG regulations for existing natural gas combustion turbines; however, no rule has been proposed. As the timeline for compliance with the new standards is accelerated and must be considered in tandem with the new EPA MATS Rule, which is also subject to ongoing legal challenges, it is possible the Company will need to make operating decisions about the future of Colstrip before the Company has clarity about the outcome of the litigation. Pennsylvania RGGI. In October 2019, the then-Governor of Pennsylvania signed an Executive Order directing the Pennsylvania Department of Environmental Protection (the “PDEP”) to draft regulations establishing a cap-and-trade program with the intent of enabling Pennsylvania to join the RGGI, a multi-state regional cap-and-trade program comprised of several Eastern U.S. states. In April 2022, Pennsylvania entered the RGGI program, with compliance set to begin on July 1, 2022. However, in November 2023, the Commonwealth Court of Pennsylvania ruled RGGI was an invalid tax and voided the rulemaking. The PDEP appealed this decision to the Pennsylvania Supreme Court and filed notice with the court that the RGGI program would not be implemented while the appeal is pending. In July 2024, the Pennsylvania Supreme Court permitted certain non-profit environmental groups to intervene in the litigation. EPA ELG Rule. In November 2015, the EPA revised the effluent limitation guidelines for certain power generation facilities, which imposed more stringent standards for wastewater streams as facility discharge permits are renewed. In 2020, the EPA issued changes that would exempt coal generation facility operators from meeting certain wastewater standards if the facility would commit to cease coal-fired generation by the end of 2028, which Talen elected for its wholly owned coal operations. In May 2024, the EPA published revisions to the EPA ELG Rule, which imposed additional requirements for legacy wastewater and combustion residual leachate. Such EPA ELG Rule revisions impact Talen’s active generation facilities that have both CCR units and hold National Pollutant Discharge Elimination System (“NPDES”) discharge permits. These sites include Brandon Shores, Brunner Island, Montour, and potentially Martins Creek. Talen is evaluating what: (i) potential discharge limits may apply; (ii) treatment may be required; and (iii) the implementation timeline may be. Obligations for installing any new wastewater treatment equipment, if necessary, will not be known until each applicable state where the active generation facilities operate makes their own determination with respect to NPDES permit renewals with new limits and associated timing. As a result of the future permit conditions, additional capital expenditures and (or) AROs may be required, which may have a material impact on our results of operations and (or) financial condition. Multiple challenges, including stay requests, to the EPA ELG Rule have been filed in various U.S. Courts of Appeal by parties that include 15 states, environmental groups, and industry groups, including the Utility Water Act Group, of which Talen is a member. The appeals have been consolidated in the U.S. Court of Appeals for the Eighth Circuit, and in October 2024, stay requests were denied. In February 2025, the EPA filed a motion in the U.S. Court of Appeals for the Eight Circuit requesting that the litigation be held in abeyance for a period of 60 days with a motion to govern due at the end of that period. No assurance can be provided as to when the challenges to the EPA ELG Rule merits will be resolved or whether such challenges will be resolved in the Company’s favor. EPA CCR Rule. In April 2015, the EPA established regulations under the Resource Conservation and Recovery Act (“RCRA”) to identify CCRs as nonhazardous solid waste and provided CCR management and siting requirements. The 2015 rule was modified in 2020 after a 2018 D.C. Circuit Court of Appeals ruling found that, among other things, the EPA did not adequately regulate unlined impoundments. In its 2020 rulemaking, the EPA specified procedures for owners to extend the operating timeline of certain unlined impoundments. Talen submitted an extension request under this process for an unlined impoundment at Montour, which was withdrawn in December 2024, following the end of basin operations and the initiation of basin closure. The 2018 D.C. Circuit Court of Appeals ruling also found that the EPA did not properly address legacy surface impoundments in the 2015 CCR rule. As a result of the finding, in May 2024, the EPA finalized additional federal CCR regulations effective in November 2024, which provided new requirements for legacy CCR surface impoundments and new requirements for other CCR disposal and management areas at active power plants (“CCR Management Units” or “CCRMUs”). This rule has been challenged in the D.C. Circuit Court of Appeals by multiple parties, including two industry groups of which Talen is a member. In December 2024, the U.S. Supreme Court denied a requested stay of the legacy EPA CCR Rule. In February 2025, the D.C Circuit Court of Appeals granted EPA’s unopposed motion to hold the litigation in abeyance for 120 days. Additionally, the EPA is being challenged by other industry parties on new regulatory interpretations that could be consequential to CCR unit closure practices and costs. No assurance can be provided at this time as to when the legal challenges to the EPA CCR Rule and interpretations will be resolved or whether such challenges will be decided in the Company’s favor. Talen continues to review the new EPA CCR Rule provisions that went into effect in 2024, perform the required applicability assessments, and await additional information and guidance from the EPA concerning the rule’s requirements. Pursuant to the regulations, initial facility evaluation reports to identify CCR areas which may become regulated and subject to the rule’s requirements are due in February 2026. Following that, site investigation may be required to further investigate applicability, and a subsequent facility report is due in February 2027. The Company has initiated reviews under the facility evaluation report requirements at locations with ash impoundments that have long since ceased coal operations as well as at locations with current coal operations. No assurance can be provided as to whether any specific ash impoundments owned by the Company may or may not be within scope of the updated EPA CCR Rule until the Company completes its assessments within the regulatory timeframe. As of December 31, 2024 (Successor), the Company has recognized required cost estimates in order to comply with the EPA CCR Rule’s initial compliance requirements and deadlines, including the initial groundwater monitoring requirements. The Company does not yet have sufficient information available to estimate costs for the future compliance obligations under the rule. As the Company continues its applicability evaluations and site assessments to determine the scope of work on its properties imposed by the new rule, additional new AROs and (or) revisions could be required. It is expected estimates will be available, under the timeline provided for by the regulations, as described above, at the completion of the initial facility evaluation reports or at the completion of a subsequent site investigation. Such AROs or ARO changes could be material and, as a result, may have a material impact on our results of operations and (or) financial condition. Certain Resolved Matters Pension Litigation. In July 2024, a U.S. District Court in Pennsylvania approved the settlement of a class action lawsuit brought by former Talen employees alleging they were owed enhanced benefits under the TERP. Pursuant to the settlement, Talen agreed to pay: (i) $6 million for settlement administrative costs and plaintiff attorneys fees, which were partially offset by insurance recoveries; and (ii) $14 million to class members from the TERP. Both payment obligations were substantially completed during the year ended December 31, 2024 (Successor). PPL/Talen Montana Litigation. In December 2023, a settlement was reached in (i) a 2018 class action lawsuit filed by the Talen Montana Retirement Plan against PPL and its affiliates claiming that an improper $733 million distribution to PPL left Talen Montana insolvent; and (ii) a related 2018 lawsuit filed by PPL against Talen and affiliates seeking various substantive and procedural relief in the first case. Under the terms of the settlement, PPL paid Talen Montana $115 million in exchange for a full release of claims, with $11 million of that amount remitted to the general unsecured creditors trust established under the Plan of Reorganization. As a result, a $104 million net gain is presented as “Other non-operating income (expense), net” on the Consolidated Statements of Operations for the year ended December 31, 2023 (Successor). Winter Storm Elliott. During December 2022, as a result of Winter Storm Elliott, PJM experienced conditions that resulted in PJM declaring a Capacity Performance event. In April 2023, we and certain other market participants filed FERC complaints against PJM disputing a portion of the penalties charged by PJM to generators (including us) for failing to meet PJM’s Capacity Performance requirements. In December 2023, FERC approved a market-wide settlement resolving all Winter Storm Elliot complaints, including ours, which reduced our net aggregate penalties to an estimated $28 million. Utilizing the best available information of PJM’s assessments: (i) an initial penalty of $33 million was recognized for the year ended December 31, 2022 (Predecessor); (ii) an increase of $13 million for the period from January 1 through May 17, 2023 (Predecessor); and (iii) an increase of $2 million for the period from May 18 through December 31, 2023 (Successor). At the time of FERC’s approval, aggregate net penalty payments of $29 million had been remitted to PJM. Accordingly, in December 2023 as a result of FERC’s approval, the remaining $19 million estimated liability was derecognized. Guarantees and Other Assurances In the normal course of business, the Company enters into agreements to provide financial performance assurance to third parties on behalf of certain subsidiaries. These agreements primarily support or enhance the stand-alone creditworthiness attributed to a subsidiary or facilitate the commercial activities in which these subsidiaries engage. Such agreements may include guarantees, stand-by LCs, and (or) surety bonds. Additionally, they may include customary indemnifications to third parties related to asset sales and other transactions. The probability of expected material payment and (or) performance for these assurance agreements is believed to be remote. Surety Bonds. Surety bonds provide financial performance assurance to third parties on behalf of certain Company subsidiaries for obligations including but not limited to environmental obligations and AROs. In the event of nonperformance by the applicable subsidiary, the beneficiary would make a claim to the surety, and the Company would be required to reimburse any payment by the surety. Talen’s liability with respect to any particular surety bond is released once the obligations secured by the surety bond are performed. Surety bond providers generally have the right to request additional collateral or request that such bonds be replaced by alternate surety providers. As of December 31, 2024 (Successor) and December 31, 2023 (Successor), the aggregate amount of surety bonds outstanding was $234 million and $240 million, respectively, including surety bonds posted on behalf of Talen Montana as discussed below. Talen Montana Financial Assurance. Pursuant to the Colstrip Administrative Order on Consent (the “Colstrip AOC”), Talen Montana, in its capacity as the Colstrip operator, is obligated to close and remediate coal ash disposal impoundments at Colstrip. The Colstrip AOC specifies an evaluation process between Talen Montana and the MDEQ on the scope of remediation and closure activities, requires the MDEQ to approve such scope, and requires financial assurance to be provided to the MDEQ on approved plans. Each of the co-owners of Colstrip has provided its proportionate share of financial assurance to the MDEQ for estimates of coal ash disposal impoundments remediation and closure activities approved by the MDEQ. The aggregate amount of surety bonds posted to the MDEQ on behalf of Talen Montana’s proportionate share of such activities was $125 million and $115 million as of December 31, 2024 (Successor) and December 31, 2023 (Successor), respectively. Talen Montana’s surety bond requirements may increase due to scope changes, cost revisions, and (or) other factors when the MDEQ conducts annual reviews of approved remediation and closure plans as required under the Colstrip AOC. The surety bond requirements are expected to decrease as Colstrip’s coal ash impoundments remediation and closure activities are completed. See Note 11 for additional information on Colstrip AROs. Other Commitments and Contingencies Nuclear Insurance. The Price-Anderson Act is a federal law that governs liability-related issues and ensures the availability of funds for public liability claims arising from a nuclear incident at any U.S. licensed nuclear facility. It also seeks to limit the liability of nuclear reactor owners for such claims from any single incident. As of December 31, 2024 (Successor), the liability limit per incident is $16.3 billion for such claims, which is funded by insurance coverage from American Nuclear Insurers ($500 million in coverage), with the remainder covered by an industry retrospective assessment program. As of December 31, 2024 (Successor), under the industry retrospective assessment program, in the event of a nuclear incident at any of the reactors covered by the Price-Anderson Act, Susquehanna could be assessed deferred premiums of up to $332 million per incident, payable at a maximum of $49 million per year. Additionally, Susquehanna purchases property insurance programs from Nuclear Electric Insurance Limited (“NEIL”), an industry mutual insurance company of which Susquehanna is a member. As of December 31, 2024 (Successor), facilities at Susquehanna are insured against nuclear property damage losses up to $2 billion and non-nuclear property damage losses up to $1 billion. Susquehanna also purchases an insurance program that provides coverage for the cost of replacement power during prolonged outages of nuclear units caused by certain specified conditions. Under the NEIL property and replacement power insurance programs, Susquehanna could be assessed retrospective premiums in the event of the insurers’ adverse loss experience. The maximum assessment for this premium is $48 million as of December 31, 2024 (Successor). Talen has additional coverage that, under certain conditions, may reduce this exposure. Talen Montana Fuel Supply. Talen Montana purchases coal from a mine owned by Westmoreland Rosebud Mining, LLC (the “Rosebud Mine”) for its interest in Colstrip Units 3 and 4 under a full requirements contract with the mine operator. Two lawsuits have been brought against the Rosebud Mine challenging permits issued to it by the State of Montana. Talen Montana is not party to either lawsuit, but is monitoring the progress of each to assess the impact to its operations. In the first lawsuit, the Montana Supreme Court affirmed a lower court’s ruling to vacate a mining permit and require the Montana Board of Environmental Review to perform an additional review of the permit. In the second lawsuit, the Montana Federal District Court ordered a branch of the U.S. Department of the Interior to complete an updated Environmental Impact Statement (“EIS”). In December 2024, the Montana Federal District Court granted an extension to the EIS completion date to October 7, 2025. At this time, Talen cannot predict the effect that an adverse outcome of these lawsuits to Rosebud Mine would have on: (i) Talen Montana’s ability to source fuel for its share of Colstrip operations; or (ii) Talen Montana’s operations, results of operations, or liquidity.

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	350,000,000	350,000,000
Shares issued (in shares)	45,961,910	59,028,843
Shares outstanding (in shares)	45,961,910	59,028,843	59,028,843

Nuclear Decommissioning Trust Funds - Schedule of Unrealized Gain (Loss) on Nuclear Decommissioning Trust Funds (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Cash equivalents, Amortized Cost	$ 328	$ 400	$ 169
Cash equivalents, Fair Value	3	9
Fair value of equity	509	491
Equity securities, Unrealized Gains	651	575
Equity securities, Unrealized Losses	55	53
Equity securities, Fair Value	1,105	1,013
Debt securities, Amortized Cost	615	570
Debt securities, Unrealized Gains	3	10
Debt securities, Unrealized Losses	7	1
Debt securities	611	579
Receivables (payables), net, Amortized Cost	5	(26)
Receivables (payables), net, Fair Value	5	(26)
Amortized Cost	1,132	1,044
Unrealized Gains	654	585
Unrealized Losses	62	54
NDT funds	1,724	1,575	$ 1,465
Cash equivalents
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Cash equivalents, Amortized Cost	3	9
Cash equivalents, Fair Value	$ 3	$ 9

Stock-Based Compensation - Stock-based Compensation Expense (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Share-Based Payment Arrangement [Abstract]
Stock-based compensation expense	$ 0	$ 19	$ 33	$ 0
Income tax benefit		(2)	(8)
After-tax stock-based compensation expense		$ 17	$ 25

Stock-Based Compensation

12 Months Ended

Dec. 31, 2024

Share-Based Payment Arrangement [Abstract]

Stock-Based Compensation

16. Stock-Based Compensation

In June 2023, TEC began granting PSUs and RSUs to certain employees and non-employee directors under the 2023 Equity Incentive Plan. The aggregate number of shares authorized for issuance under the 2023 Talen Equity Plan is 7,083,461 shares.

Stock-based Compensation Expense

Stock-based compensation expense presented as “General and administrative” on the Consolidated Statement of Operations for the periods was:


	Successor
	Year Ended December 31, 2024		May 18 through December 31, 2023
Stock-based compensation expense	$	33	$	19
Income tax benefit	(8)		(2)
After-tax stock-based compensation expense	$	25	$	17

Performance Stock Units

PSUs vest three years after Emergence or a consummation of a change in control event based on the satisfaction of a continued employment condition and the achievement of certain market conditions over a performance period. Participants will be awarded additional PSUs if market conditions exceed targets at the time of vesting. If the Company declares any cash dividends while the PSUs are outstanding, participants will be credited a dividend, payable at the time of vesting, based on the number of shares of common stock underlying the PSUs. The following table summarizes the Company’s non-vested PSUs and changes during the year:


	Successor
	Units	Weighted-Average Grant Date Fair Value per Unit
Non-vested as of December 31, 2023 (Successor)	968,793	$	54.35
Granted	4,945	96.00
Forfeited	(17,391)	72.75

Non-vested as of December 31, 2024 (Successor)	956,347	$	54.23

As of December 31, 2024, $24 million of unrecognized compensation cost related to unvested PSUs granted are expected to be recognized over a weighted average period of approximately 1.5 years.


	Successor
	Year Ended December 31, 2024		May 18 through December 31, 2023
Volatility (a)	25	%	25	%
Expected term (in years)	2.4		3
Risk-free rate (b)	4.29	%	4.35% - 4.59%

__________________

(a) Derived from an option pricing method based on the average asset volatility of peer companies and the Company’s leverage ratio.

(b) Based on the U.S. constant maturity treasury rate with a term matching the expected time to the end of the performance measurement period.

Restricted Stock Units

RSUs have three-year ratable vesting schedules beginning on the grant date, with restrictions on transferring settled shares prior to the final scheduled vesting date for each award. The fair value of the RSUs granted is derived from the closing price of TEC common stock on the grant date. The following table summarizes the Company’s non-vested RSUs and changes during the year:


	Successor
	Units	Weighted-Average Grant Date Fair Value per Unit
Non-vested as of December 31, 2023 (Successor)	845,269	$	48.46
Granted	56,346	121.89
Forfeited	(56,594)	55.01
Vested	(295,616)	48.90
Non-vested as of December 31, 2024 (Successor)	549,405	$	55.07

RSUs vested during the year ended December 31, 2024 (Successor) were settled in cash for $32 million.

As of December 31, 2024, $22 million of unrecognized compensation cost related to unvested RSUs granted are expected to be recognized over a weighted average period of approximately 1.5 years.

Consolidated Balance Sheets - USD ($)
$ in Millions

Dec. 31, 2024

Dec. 31, 2023

Assets

Cash and cash equivalents

$ 328

$ 400

Restricted cash and cash equivalents (Note 19)

501

Accounts receivable (Note 6)

123

137

Inventory, net (Note 8)

302

375

Derivative instruments (Notes 5 and 14)

Other current assets

184

Total current assets

1,040

1,554

Property, plant and equipment, net (Note 10)

3,154

3,839

Nuclear decommissioning trust funds (Notes 9 and 14)

1,724

1,575

Derivative instruments (Notes 5 and 14)

Other noncurrent assets

183

147

Total Assets

6,106

7,121

Liabilities and Equity

Long-term debt, due within one year (Notes 13 and 14)

Accrued interest

Accounts payable and other accrued liabilities

266

344

Derivative instruments (Notes 5 and 14)

Other current liabilities

154

Total current liabilities

455

486

Long-term debt (Notes 13 and 14)

2,987

2,811

Derivative instruments (Notes 5 and 14)

Postretirement benefit obligations (Note 15)

305

368

Asset retirement obligations and accrued environmental costs (Note 11)

468

469

Deferred income taxes (Note 7)

362

407

Other noncurrent liabilities

135

Total Liabilities

4,719

4,587

Commitments and Contingencies (Note 12)

Stockholders’ Equity

Common stock

^[1]

Additional paid-in capital

1,725

2,346

Accumulated retained earnings (deficit)

(326)

134

Accumulated other comprehensive income (loss)

(12)

(23)

Total Stockholders' Equity

1,387

2,457

Noncontrolling interests

Total Equity

1,387

2,534

Total Liabilities and Equity

$ 6,106

$ 7,121

[1]	(a)45,961,910 and 59,028,843 shares issued and outstanding as of December 31, 2024 (Successor) and December 31, 2023 (Successor), respectively.

Stockholder's Equity - Narrative (Details) $ in Millions	1 Months Ended				5 Months Ended	7 Months Ended	12 Months Ended
Stockholder's Equity - Narrative (Details) $ in Millions	Nov. 30, 2024 shares	Oct. 31, 2024 USD ($)	Jul. 31, 2024 shares	Mar. 31, 2024 USD ($) member Rate	May 17, 2023 USD ($) shares	Dec. 31, 2023 USD ($) shares	Dec. 31, 2024 USD ($) Rate shares	Dec. 31, 2022 USD ($)	Feb. 27, 2025 shares	Sep. 30, 2024 USD ($)	May 31, 2024 USD ($)	Jun. 30, 2023 shares
Equity, Class of Treasury Stock [Line Items]
Shares outstanding (in shares)					59,028,843	59,028,843	45,961,910
Warrants exercised (in shares)			457,142
Stock issued (in shares)			160,289
Share repurchase program, authorized, amount \| $											$ 300
Share repurchase program, remaining authorized amount \| $							$ 1,100			$ 1,250	$ 1,000
Percentage of common stock purchased \| Rate							22.00%
Stock repurchased, excluding excise tax \| $							$ 1,950
Number of shares authorized (in shares)												7,083,461
Repurchase of noncontrolling interest \| $					$ 0	$ 19	$ 125	$ 0
Number of former members, equity units acquired \| member				2
Nautilus Cryptomine LLC
Equity, Class of Treasury Stock [Line Items]
Repurchase of noncontrolling interest \| $		$ 85
Ownership percentage		100.00%
Nautilus Cryptomine LLC \| TeraWulf
Equity, Class of Treasury Stock [Line Items]
Ownership percentage, noncontrolling owner		25.00%
Cumulus Digital Holdings LLC
Equity, Class of Treasury Stock [Line Items]
Repurchase of noncontrolling interest \| $				$ 39
Ownership percentage \| Rate				100.00%
Employee Stock
Equity, Class of Treasury Stock [Line Items]
Purchase price of common stock, offering date, percentage	85.00%
Purchase price of common stock, exercise date, percentage	85.00%
Number of shares authorized (in shares)	500,000
Maximum number of shares issued (in shares)	5,000,000
Minimum \| Employee Stock
Equity, Class of Treasury Stock [Line Items]
Percentage of eligible compensation	1.00%
Maximum \| Employee Stock
Equity, Class of Treasury Stock [Line Items]
Percentage of eligible compensation	10.00%
Subsequent Event
Equity, Class of Treasury Stock [Line Items]
Shares outstanding (in shares)									45,961,910

Inventory

12 Months Ended

Dec. 31, 2024

Inventory Disclosure [Abstract]

Inventory

8. Inventory


	Successor
	December 31, 2024		December 31, 2023
Coal	$	92	$	152
Oil products	65		75
Fuel inventory for electric generation	157		227
Materials and supplies, net	88		72
Environmental products	57		76
Inventory, net	$	302	$	375

Inventory net realizable value and obsolescence charges on coal and fuel oil inventories are presented as “Other operating income (expense), net” on the Consolidated Statements of Operations. Such non-cash charges were non-material for the year ended December 31, 2024 (Successor), non-material for the period from May 18 through December 31, 2023 (Successor), $37 million for the period from January 1 through May 17, 2023 (Predecessor), and non-material for the year ended December 31, 2022 (Predecessor).

During the period from January 1 through May 17, 2023 (Predecessor), $24 million of adjustments were related to Brandon Shores coal and materials and supplies inventories. See Note 10 for additional information on the Brandon Shores recoverability assessment.

Fresh Start Accounting - Schedule of Enterprise Value (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023
Plan of Reorganization [Abstract]
Enterprise value			$ 4,500
Plus: Cash and cash equivalents and Restricted cash and cash equivalents			701
Less: Fair value of debt	$ (3,120)	$ (2,934)	(2,845)
Less: Liability-classified warrants			(35)
Total Stockholders' Equity	1,387	2,457	2,321
Plus: Fair value of noncontrolling interest	0	77	110
Total Equity	$ 1,387	$ 2,534	$ 2,431

- Definition

Amount of equity (deficit) attributable to noncontrolling interest. Excludes temporary equity.

+ References

+ Details

- Definition

Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest.

+ References

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+ Details

- Definition

Amount of equity (deficit) attributable to parent and noncontrolling interest. Excludes temporary equity.

+ References

+ Details

Risk Management, Derivative Instruments and Hedging Activities - Schedule of Net Notional Volumes of Open Commodity Derivatives and Interest Rate Derivatives (Details) $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($) MWh MMBTU T	Dec. 31, 2023 USD ($) MWh MMBTU T
Commodity derivatives \| Short
Derivative [Line Items]
Commodity purchase (sales) derivatives, power and natural gas \| MWh	(38,615,192)	(27,557,871)
Commodity derivatives \| Long
Derivative [Line Items]
Commodity purchase (sales) derivatives, power and natural gas \| MMBTU	(32,405,460)	(8,314,060)
Commodity purchase (sales) derivatives, emission allowances \| T	100,000	500,000
Interest rate derivatives
Derivative [Line Items]
Interest rate (in millions) \| $	$ 290	$ 290

Long-term Debt and Other Credit Facilities (Tables)

12 Months Ended

Dec. 31, 2024

Debt Disclosure [Abstract]

Schedule of Long-Term Debt


		Successor
	Interest Rate (a)	December 31, 2024		December 31, 2023
TLB-1	7.02 %	$	857	$	866
TLB-2	7.02 %	850		—
TLC (b)	N/A	—		470
Secured Notes	8.63 %	1,200		1,200
PEDFA 2009B Bonds	5.25 %	50		50
PEDFA 2009C Bonds	5.25 %	81		81
Cumulus Digital TLF (b)	N/A	—		182
Total principal		3,038		2,849
Unamortized deferred financing costs and original issuance discounts		(34)		(29)
Total carrying value		3,004		2,820
Less: long-term debt, due within one year		17		9
Long-term debt		$	2,987	$	2,811

__________________

(a)Computed interest rate as of December 31, 2024 (Successor).

(b)See “Recent Transactions” below for additional information on extinguishments of indebtedness.

Schedule of Maturities of Long-Term Debt

Long-term debt maturities as of December 31, 2024 (Successor) were:


	2025		2026		2027		2028		2029		Thereafter		Total
Principal debt maturities	$	17	$	17	$	17	$	17	$	17	$	2,952	$	3,038

Schedule of Line of Credit Facilities


		Successor
		December 31, 2024
	Maturity	Committed Capacity (a)		Direct Cash Borrowings		LCs Issued		Unused Capacity
RCF	December 2029	$	700	$	—	$	—	$	700
LCF	December 2026	900		—		374		526


Total		$	1,600	$	—	$	374	$	1,226

__________________

(a)RCF committed capacity can be used for direct cash borrowings and (or) LCs.

Summary Of Key Terms Of Indebtedness

Certain key terms of our indebtedness include:

Secured Notes

TLB-1

TLB-2

RCF

LCF

PEDFA Bonds

Maturity:

June 2030

May 2030

December 2031

December 2029

December 2026

2009B: December 2038

2009C: December 2037

Index:

None

Term SOFR

None

Rate, Applicable Margin, and Amortization:

8.625% per annum fixed rate

No applicable margin

No amortization

2.50% per annum applicable margin; leverage-based step-downs to 2.25% and 2.00%

Amortization 1.00% per annum; paid quarterly

Same as TLB-1

Cash borrowings: 2.00% per annum applicable margin; leverage-based step-downs to 1.75% and 1.50%

LCs: LC fee equal to applicable margin above + fronting fee of 0.125%

Unused commitments: 0.375%; leverage-based step-down to 0.25%

No amortization

LCs: Same as RCF

Unused commitments: Same as RCF

5.25% per annum fixed rate

No applicable margin

No amortization

Prepayment Penalty:

Prior to June 1, 2026: Redeemable at par plus a customary “make-whole” premium. 40% redeemable from the proceeds of certain equity offerings at 108.625%. 10% redeemable at 103% from June 1, 2025 – May 31, 2026

On or after June 1 of the following years: 2026: 104.313%; 2027: 102.156%; 2028 and after: 100%

1.00% to the extent prepaid prior to June 20, 2025 in connection with a repricing transaction

1.00% to the extent prepaid prior to June 13, 2025 in connection with a repricing transaction

None

Prior to June 1, 2026: Par plus a customary “make-whole” premium

On or after June 1, 2026: Par

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

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+ Details

Commitments and Contingencies - Environmental Matters (Details)	1 Months Ended
	Feb. 28, 2025	Nov. 30, 2024 group	May 31, 2024 attorney_general state
Environmental Matters, Coal \| Subsequent Event
Other Commitments [Line Items]
Days in abeyance	60 days
Environmental Matters, Air
Other Commitments [Line Items]
Number of state attorney generals			23
Environmental Matters, Air \| Subsequent Event
Other Commitments [Line Items]
Days in abeyance	90 days
Environmental Matters, Federal Climate Change Actions
Other Commitments [Line Items]
Number of states represented by coalitions \| state			27
Environmental Matters, Federal Climate Change Actions \| Subsequent Event
Other Commitments [Line Items]
Days in abeyance	60 days
Environmental Matters, Effluent Limitation Guidelines
Other Commitments [Line Items]
Number of state attorney generals			15
Number of groups that challenged the EPA CCR Rule \| group		2
Environmental Matters, Effluent Limitation Guidelines \| Subsequent Event
Other Commitments [Line Items]
Days in abeyance	60 days
Days in abeyance, approved	120 days

Asset Retirement Obligations and Accrued Environmental Costs - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023	Dec. 31, 2022
Asset Retirement Obligation [Line Items]
Fair Value	$ 1,724	$ 1,575	$ 1,465
Asset retirement obligations and accrued environmental costs due after one year	468	469	442
Asset retirement obligations	498	464	$ 766	$ 751
Accrued environmental costs	$ 21	23
Discount rate	8.41%
Undiscounted amount of liabilities	$ 32	34
Susquehanna
Asset Retirement Obligation [Line Items]
Asset retirement obligations and accrued environmental costs due after one year	242
Talen Montana
Asset Retirement Obligation [Line Items]
Asset retirement obligations	$ 98	$ 107

Risk Management, Derivative Instruments and Hedging Activities - Balance Sheets Presentation (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023
Derivative [Line Items]
Derivative asset, current	$ 66	$ 89	$ 186
Derivative liability, current	0	32	57
Derivative asset, noncurrent	5	6	0
Derivative liability, noncurrent	7	11	$ 42
Commodity derivatives
Derivative [Line Items]
Derivative asset, current	65	88
Derivative liability, current	0	32
Derivative asset, noncurrent	4	6
Derivative liability, noncurrent	7	5
Interest rate derivatives
Derivative [Line Items]
Derivative asset, current	1	1
Derivative liability, current	0	0
Derivative asset, noncurrent	1	0
Derivative liability, noncurrent	$ 0	$ 6

Fair Value (Tables)

12 Months Ended

Dec. 31, 2024

Fair Value Disclosures [Abstract]

Summary of Recurring Fair Value Measurements

The classifications of recurring fair value measurements within the fair value hierarchy were:


	Successor
	December 31, 2024								December 31, 2023
	Level 1		Level 2		NAV		Netting (a)		Total		Level 1		Level 2		NAV		Netting (a)		Total
Assets
Cash equivalents	$	—	$	—	$	3	$	—	$	3	$	—	$	—	$	9	$	—	$	9
Equity securities (b)	758		—		347		—		1,105		629		—		384		—		1,013
U.S. Government debt securities	353		—		—		—		353		337		—		—		—		337
Municipal debt securities	—		85		—		—		85		—		86		—		—		86
Corporate debt securities	—		173		—		—		173		—		156		—		—		156

Receivables (payables), net (c)	—		—		—		—		5		—		—		—		—		(26)
NDT funds	1,111		258		350		—		1,724		966		242		393		—		1,575

Commodity derivatives	134		91		—		(156)		69		98		196		—		(200)		94
Interest rate derivatives	—		2		—		—		2		—		1		—		—		1
Total assets	$	1,245	$	351	$	350	$	(156)	$	1,795	$	1,064	$	439	$	393	$	(200)	$	1,670

Liabilities
Commodity derivatives	$	145	$	29	$	—	$	(167)	$	7	$	155	$	139	$	—	$	(257)	$	37
Interest rate derivatives	—		—		—		—		—		—		6		—		—		6

Total liabilities	$	145	$	29	$	—	$	(167)	$	7	$	155	$	145	$	—	$	(257)	$	43

__________________

(a)Amounts represent netting pursuant to master netting arrangements and cash collateral held or placed with the same counterparty.

(b)Includes commingled equity and fixed income funds and real estate investment trusts.

(c)Represents: (i) interest and dividends earned but not received; and (ii) net sold or purchased investments, but not settled.

Summary of Carrying Value and Fair Value of Indebtedness

The carrying value and fair value of indebtedness presented on the Consolidated Balance Sheets were:


	Successor
	December 31, 2024				December 31, 2023
	Carrying Value		Fair Value		Carrying Value		Fair Value

Long-term debt (a)	$	3,004	$	3,120	$	2,820	$	2,934
Other short-term indebtedness (b)	—		—		6		6

__________________

(a)Aggregate value of “Long-term debt” and “Long-term debt, due within one year” presented on the Consolidated Balance Sheets.

(b)Presented as “Other current liabilities” on the Consolidated Balance Sheets.

Cover Page - USD ($) $ in Billions	12 Months Ended
Cover Page - USD ($) $ in Billions	Dec. 31, 2024	Feb. 27, 2025	Jun. 28, 2024
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2024
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-37388
Entity Registrant Name	Talen Energy Corporation
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	47-1197305
Entity Address, Address Line One	2929 Allen Pkwy, Suite 2200
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77019
City Area Code	888
Local Phone Number	211-6011
Title of 12(b) Security	Common stock, par value $0.001 per share
Trading Symbol	TLN
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction Flag	false
Entity Public Float			$ 5.9
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		45,961,910
Documents Incorporated by Reference	The information required pursuant to Part III of this Form 10-K will be set forth in, and incorporated by reference from, the registrant’s definitive proxy statement for the 2025 annual meeting of stockholders (the “2025 Proxy Statement”), which will be filed with the Securities and Exchange Commission not later than 120 days after the end of the fiscal year ended December 31, 2024.
Entity Central Key Index	0001622536
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	FY
Amendment Flag	false

Postretirement Benefit Obligations

12 Months Ended

Dec. 31, 2024

Retirement Benefits [Abstract]

Postretirement Benefit Obligations

15. Postretirement Benefit Obligations

TES and certain subsidiaries sponsor postemployment benefits which include defined benefit pension plans, health and welfare postretirement plans (other postretirement benefit plans), and a defined contribution plan.

Pension and Other Postretirement Defined Benefit Plans

Obligations under the defined benefit pension and other postretirement plans are generally based on factors, among others, such as age of the participants, years of service, and compensation. The pension and other postretirement plans are closed to new participants. Effective December 31, 2018, all participants ceased accruing additional benefits in the TERP, the Company’s largest defined benefit pension plan.

Funded Status. The net fair value of underfunded defined benefit pension and other postretirement plans are presented as “Postretirement benefit obligations” on the Consolidated Balance Sheets. Certain other postretirement plans were overfunded by $36 million and $33 million as of December 31, 2024 (Successor) and 2023 (Successor), respectively, and are presented as “Other noncurrent assets” on the Consolidated Balance Sheets. The current portion of certain unfunded postretirement obligations were non-material.

The aggregate funded status and the weighted average assumptions for the periods were:


	Pension Benefits
	Successor						Predecessor
	Year Ended December 31, 2024			May 18 through December 31, 2023			January 1 through May 17, 2023

Change in benefit obligation
Benefit obligation beginning balance	$	1,308		$	1,300		$	1,273
Service cost	2			2			1
Interest cost	63			40			25
Actuarial (gain) loss	(81)			20			6
Actual benefits paid	(105)			(55)			(34)
Resolved litigation settlement and other charges	15			1			—
Benefit obligation ending balance	$	1,202		$	1,308		$	1,271
Change in plan assets
Plan assets fair value beginning balance	975			997			994
Actual return on plan assets	(13)			24			35
Employer contributions	54			9			2
Actual benefits paid	(105)			(55)			(34)
Plan assets fair value ending balance	$	911		$	975		$	997
Funded status	$	(291)		$	(333)		$	(274)
Accumulated benefit obligation	$	1,202		$	1,308		$	1,271
Aggregate amounts of underfunded plans
Benefit obligation/Accumulated benefit obligation	1,202			1,308			1,271
Fair value of plan assets	911			975			997
Amounts recognized in accumulated other comprehensive income
Net (gain) loss	34			37			238
Total accumulated other comprehensive income	$	34		$	37		$	238
Assumptions
Discount rate	5.65		%	5.00		%	5.37		%
Interest crediting rate	6.00		%	6.00		%	6.00		%
Rate of compensation increase	3.45		%	3.45		%	3.45		%


	Other Postretirement Benefits
	Successor						Predecessor
	Year Ended December 31, 2024			May 18 through December 31, 2023			January 1 through May 17, 2023

Change in benefit obligation
Benefit obligation beginning balance	$	79		$	78		$	77
Service cost	1			1			—
Interest cost	3			2			1
Plan amendments	(21)			—			—
Actuarial (gain) loss	(3)			1			1
Plan participant contributions	2			2			1
Actual benefits paid	(9)			(5)			(4)
Benefit obligation ending balance	$	52		$	79		$	76
Change in plan assets
Plan assets fair value beginning balance	75			74			75
Actual return on plan assets	3			4			2

Plan participant contributions	2			2			1
Actual benefits paid	(9)			(5)			(4)
Plan assets fair value ending balance	$	71		$	75		$	74
Funded status	$	19		$	(4)		$	(2)

Aggregate amounts of underfunded plans
Benefit obligation / Accumulated benefit obligation	$	52		$	78		$	76
Fair value of plan assets	71			75			74
Amounts recognized in accumulated other comprehensive income
Net (gain) loss	(2)			(1)			4
Prior service cost (credit)	(20)			—			(4)
Total accumulated other comprehensive income	$	(22)		$	(1)		$	—
Assumptions
Discount rate	5.63		%	5.01		%	5.36		%
Rate of compensation increase	2.31		%	2.31		%	2.31		%

During the year ended December 31, 2024 (Successor), the decrease in postretirement benefit obligations was primarily attributable to increasing interest rates, offset by actual returns being less than expected returns on plan assets.

In March 2024, $10 million of excess assets from the PA Mines United Mine Workers of America (“UMWA”) Plan VEBA were transferred to a separate VEBA, which provides benefits for participants in Talen’s health and welfare “wrap plan.” As such assets were not presented on the Consolidated Balance Sheets prior to the transfer of the assets from the VEBA, a transfer gain of $10 million was recognized for the year ended December 31, 2024 (Successor) and presented as “Other non-operating income (expense), net” on the Consolidated Statements of Operations.

Net Periodic Benefit Cost and Amounts Recognized in OCI. Service cost is presented as “Postretirement benefits service (credit) costs, net,” while the other components of net periodic defined benefit cost (credit) for pension and other postretirement plans are presented as “Operation, maintenance and development” on the Consolidated Statements of Operations. The portion of net periodic benefit cost capitalized during the year ended December 31, 2024 (Successor) and during the periods from May 18 through December 31, 2023 (Successor), and during the periods from January 1 through May 17, 2023 (Predecessor) was not material.

The components of net periodic benefit cost (credit), the amounts recognized in OCI and the associated weighted average assumptions for pension and other postretirement plans for the periods were:


	Pension Benefits
	Successor						Predecessor
	Year Ended December 31, 2024			May 18 through December 31, 2023			January 1 through May 17, 2023			Year Ended December 31, 2022
Net periodic benefit costs (credits):
Service cost	$	2		$	2		$	1		$	4
Interest cost	63			40			25			50
Expected return on plan assets	(66)			(41)			(30)			(68)
Amortization of net (gain) loss	—			—			2			27
Resolved litigation settlement and other charges	15			1			—			—
Net periodic defined benefit cost (credit)	14			2			(2)			13
Net actuarial (gain) loss	(3)			38			2			19
Reclassifications due to settlement and (or) curtailment:
Amortization of net (gain) loss	—			—			—			(27)
Total recognized in OCI	$	(3)		$	38		$	2		$	(8)
Total recognized in net periodic costs and OCI	$	11		$	40		$	—		$	5
Assumptions
Discount rate	5.00		%	5.12		%	5.41		%	2.97		%
Rate of compensation increase	3.45		%	3.45		%	3.45		%	3.45		%
Expected return on plan assets	7.25		%	7.25		%	7.50		%	5.75		%


	Other Postretirement Benefits
	Successor						Predecessor
	Year Ended December 31, 2024			May 18 through December 31, 2023			January 1 through May 17, 2023			Year Ended December 31, 2022
Net periodic benefit costs (credits):
Service cost	$	1		$	1		$	1		$	1
Interest cost	3			2			1			3
Expected return on plan assets	(4)			(2)			(2)			(4)
Amortization of prior service cost (credit)	(1)			—			—			(1)
Net periodic defined benefit cost (credit)	(1)			1			—			(1)
Net actuarial (gain) loss	(2)			(1)			—			(3)
Prior service credit	(21)			—			—			—
Reclassifications due to settlement and (or) curtailment:
Amortization of prior service cost (credit)	1			—			—			1
Amortization of net (gain) loss	—			—			—			(1)
Total recognized in OCI	$	(22)		$	(1)		$	—		$	(3)
Total recognized in net periodic costs and OCI	$	(23)		$	—		$	—		$	(4)
Assumptions
Discount rate	5.01		%	5.13		%	5.41		%	2.94		%
Rate of compensation increase	2.31		%	2.31		%	2.31		%	2.31		%
Expected return on plan assets	5.49		%	5.49		%	5.74		%	3.89		%
Health care grading trend rates (a)	7.10% to 4.40%			6.50% to 4.50%			6.50% to 4.50%			4.50		%

__________________

(a)Trend rates grading to 2027.

In September 2024, the Company approved a plan amendment for certain other postretirement benefit plans, resulting in the recognition of prior service credits of $21 million and presented as “Postretirement benefit prior service (credits) costs, net” on the Consolidated Statements of Comprehensive Income (Loss).

See Note 12 for additional information on recently resolved litigation regarding certain of our defined benefit pension obligations.

The expected long-term rates of return for pension and other postretirement plans are based on management's projections using a best-estimate of expected returns, volatilities, and correlations for each asset class. Each plan’s specific current and expected asset allocations are also considered in developing a reasonable return assumption.

Contributions and Payments. TES contributed $43 million and $5 million to the TES sponsored pension plan during the year ended December 31, 2024 (Successor) and the period from May 18 through December 31, 2023 (Successor), respectively. There were no contributions for the pension plans during the period from January 1 through May 17, 2023 (Predecessor). Talen Montana contributed $10 million, $4 million, and $2 million of discretionary contributions to the Talen Montana sponsored pension plan during the year ended December 31, 2024 (Successor) and for the periods from May 18 through December 31, 2023 (Successor), and January 1 through May 17, 2023 (Predecessor), respectively, to the Talen Montana pension plan.

TES expects to contribute $65 million to the TES sponsored pension plan in 2025. Talen Montana expects to contribute $8 million of discretionary contributions to the Talen Montana sponsored pension plan in 2025, of which $4 million is expected to be collected by Talen Montana from the other joint owners of Colstrip.

The aggregate benefits paid to pension and other postretirement plan participants was $114 million for year ended December 31, 2024 (Successor), $60 million during the period from May 18 through December 31, 2023 (Successor), and $38 million during the period from January 1 through May 17, 2023 (Predecessor).

The forecasted undiscounted benefit payments to plan participants as of December 31, 2024 (Successor) were:


	2025		2026		2027		2028		2029		2030-2034
Pension plans	$	97	$	94	$	94	$	93	$	93	$	452
Other postretirement plans	6		6		5		5		4		18

Pension plan assets. Pension plan assets are held in external trusts, including a master trust, which includes a 401(h) account that is restricted for certain other postretirement benefit obligations of Talen Energy Supply. The plans’ investment policies outline investment objectives.

The risk management framework categorizes the plan assets within three sub-portfolios: growth, immunizing, and liquidity. The trust investments within these portfolios are routinely monitored to seek a risk-adjusted return on a mix of assets that, in combination with our funding policy, will provide sufficient assets to provide long-term growth and liquidity for benefit payments, match asset duration with the expected liability duration, and mitigate concentrations of risk with asset diversification.

The weighted-average target asset allocations for the pension plan assets as of December 31, 2024 (Successor) were:


	December 31, 2024
Equity securities	32	%
Debt securities	10	%
Other	7	%
Growth portfolio	48	%
Debt securities	35	%
Other	12	%
Immunizing portfolio	47	%
Liquidity portfolio	4	%
Total	100	%

The classifications of pension plan asset fair value measurements within the fair value hierarchy were:


	Successor
	December 31, 2024				December 31, 2023
	Level 1		NAV		Total		Level 1		NAV		Total
Cash equivalents	$	—	$	100	$	100	$	—	$	169	$	169
Commingled equity securities	—		274		274		—		288		288
Commingled debt securities	—		286		286		—		301		301
Alternative and other investments	(15)		231		216		52		191		243
Receivables (payables), net (a)	—		—		35		—		—		(25)
Total trust funds	(15)		891		911		52		949		976
Restricted 401(h) assets (b)	—				—		—		—		(1)
Total plan assets	$	(15)	$	891	$	911	$	52	$	949	$	975

__________________

(a) Represents: (i) interest and dividends earned but not received; and (ii) net sold or purchased investments, but not settled.

(b) Other postretirement 401(h) benefits assets are a component of the pension plan master trust. Accordingly, these are excluded from pension plan assets.

Level 1 investments consist of exchange-traded futures contracts, which are valued using unadjusted prices available from the underlying market.

Certain investments in cash equivalent funds, commingled equity securities, commingled debt securities, and alternative investments are not classified within the fair value hierarchy. The fair value measurement of these funds is based on firm quotes of NAV per share, as a practical expedient for valuation, which are not obtained from a quoted price in an active market.

Investments in cash equivalent funds consist of short-term investment funds and commingled cash equivalent funds. Investments in equity funds consist of large and small cap U.S. and international funds that can be redeemed daily. Investments in commingled debt funds consist of funds that invest in investment-grade intermediate and long-duration corporate and government fixed-income securities. These investments can be redeemed daily.

Alternative and other investments consist of investments in funds that invest in a portfolio of exchange-traded futures and forward contracts, hedge funds of funds that employ investment strategies including long/short equity, market neutral, distressed debt, and relative value, private equity partnerships, with limited lives ranging from ten to fifteen years, and real estate investment partnerships. Investments in real estate partnerships have redemption limitations based on available funding and investments in private equity partnerships that cannot be redeemed with the partnership prior to the end of the partnerships’ lives; however, the interest may be sold to other parties. Redemptions of hedge funds, private equity, and real estate partnerships are also subject to the respective general partner's approval.

Other postretirement benefit plan assets. The investment strategy with respect to most of the other postretirement benefit obligations is to fund VEBA or similar trusts with voluntary contributions, when appropriate, and to invest in a tax efficient manner. Other postretirement benefit plans are invested in a mix of assets for long-term growth with an objective of earning returns that provide liquidity as required for benefit payments. These plans benefit from diversification of asset types, investment fund strategies and investment fund managers, and therefore, have no significant concentration of risk. Equity securities include investments in domestic large-cap commingled funds. Ownership interests in commingled funds that invest entirely in debt securities are classified as equity securities but treated as debt securities for asset allocation and target allocation purposes. Ownership interests in money market funds are treated as cash and cash equivalents for asset allocation and target allocation purposes.

The target asset allocations for other postretirement benefit assets as of December 31, 2024 (Successor) were:


	2024
Cash and cash equivalents	4	%
Equity securities	11	%
Debt securities	84	%
Total	100	%

The classifications of other postretirement benefit plan asset fair value measurements within the fair value hierarchy were:


	Successor
	December 31, 2024								December 31, 2023
	Level 1		Level 2		NAV		Total			Level 1		Level 2		NAV		Total
Cash equivalents	$	—	$	—	$	4	$	4		$	—	$	—	$	7	$	7
Commingled equity securities	—		—		10		10			—		—		9		9
U.S. Government debt securities	7		—		—		7			8		—		—		8
Corporate debt securities	—		18		—		18			—		16		—		16
Commingled debt securities	—		—		32		32			—		—		34		34
Total trust funds	7		18		46		71			8		16		50		74
Restricted 401(h) assets (a)	—		—		—		—			—		—		—		1
Total plan assets	$	7	$	18	$	46	$	71		$	8	$	16	$	50	$	75

__________________

(a) Other postretirement 401(h) benefits assets are a component of the pension plan master trust. Accordingly, these are reported as postretirement assets.

Level 1 investments consist of U.S. Treasury and (or) U.S. government debt securities, which are valued using unadjusted prices available from the underlying market.

Level 2 investments consist of corporate debt securities, which are valued using observable inputs such as benchmark yields, relevant trade data, broker/dealer bid/ask prices, benchmark securities, and credit valuation adjustments.

Certain investments in money market funds, commingled equity securities, and commingled debt securities are not classified within the fair value hierarchy. The fair value measurements of these funds are based on firm quotes of NAV per share, as a practical expedient for valuation, which are not obtained from a quoted price in an active market.

Investments in equity securities consist of investments in a passively managed equity index fund that invests in securities and a combination of other collective funds. Investments in debt securities represent investments in funds that invest in a diversified portfolio of investment grade fixed income securities.

Defined Contribution Plan

Substantially all Company employees are eligible to participate in the Company’s 401(k) deferred savings plans. Employer contributions to the plans were $25 million, $9 million, and $10 million during the year ended December 31, 2024 (Successor), for the period from May 18 through December 31, 2023 (Successor), and from the period January 1 through May 17, 2023 (Predecessor).

Coal Industry Retiree Benefit Plans

Talen is obligated under the Coal Act and the Black Lung Act to pay for certain health care and black lung benefits of retired miners and allowable beneficiaries. These obligations are funded from medical VEBAs and a black lung trust.

The funded status of each plan as of December 31, 2024 (Successor) was:


	Trust Asset Fair Value		Obligation Fair Value		Overfunded Status
Benefit Plan for UMWA Represented Retirees of Pennsylvania Mines, LLC	$	21	$	16	$	5
Coal Worker's Pneumoconiosis (Black Lung) Benefit Plan	9		5		4

Shortfalls in funded status of the plans are assessed as contingent liabilities. As the fair value of VEBA and black lung trust assets exceed the plan obligations, both VEBA and black lung trust assets and the plan obligations are not reported on the Talen Consolidated Balance Sheets. See in Note 2 for our accounting policy related to postretirement benefits.

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480794/715-70-50-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480482/715-20-55-17

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iv)(03)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (q)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (l)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/715/tableOfContent

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iii)
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-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (o)
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-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480126/715-20-S99-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 60
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480266/715-60-50-3

+ Details

Inventory (Tables)

12 Months Ended

Dec. 31, 2024

Inventory Disclosure [Abstract]

Schedule of Inventory


	Successor
	December 31, 2024		December 31, 2023
Coal	$	92	$	152
Oil products	65		75
Fuel inventory for electric generation	157		227
Materials and supplies, net	88		72
Environmental products	57		76
Inventory, net	$	302	$	375

Fresh Start Accounting - Schedule of Consolidated Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023	May 16, 2023	Dec. 31, 2022
Assets
Cash and cash equivalents	$ 328	$ 400	$ 169
Restricted cash and cash equivalents	37	501	585
Accounts receivable, net	123	137	145
Inventory, net	302	375	307
Derivative instruments	66	89	186
Other current assets	184	52	130
Total current assets	1,040	1,554	1,522
Property, plant and equipment, net (Note 10)	3,154	3,839	3,864
Nuclear decommissioning trust funds (Notes 9 and 14)	1,724	1,575	1,465
Derivative instruments	5	6	0
Other noncurrent assets	183	147	208
Total Assets	6,106	7,121	7,059	$ 7,800
Liabilities and Equity
Revolving credit facilities			0
Long-term debt, due within one year	17	9	5
Accrued interest	18	32	4
Accounts payable and other accrued liabilities	266	344	385
Derivative instruments	0	32	57
Other current liabilities	154	69	68
Total current liabilities	455	486	519
Long-term debt	2,987	2,811	2,840
Liabilities subject to compromise			0		$ 2,825
Derivative instruments	7	11	42
Postretirement benefit obligations	305	368	335
Asset retirement obligations and accrued environmental costs	468	469	442
Deferred income taxes	362	407	357
Other noncurrent liabilities	135	35	93
Total Liabilities	4,719	4,587	4,628	$ 9,800
Total Stockholders' Equity	1,387	2,457	2,321
Noncontrolling interests	0	77	110
Total Equity	1,387	2,534	2,431
Total Liabilities and Equity	6,106	$ 7,121	7,059
Predecessor
Assets
Cash and cash equivalents			1,302
Restricted cash and cash equivalents			240
Accounts receivable, net			148
Inventory, net			448
Derivative instruments			818
Other current assets			135
Total current assets			3,091
Property, plant and equipment, net (Note 10)			4,322
Nuclear decommissioning trust funds (Notes 9 and 14)			1,465
Derivative instruments			37
Other noncurrent assets			146
Total Assets			9,061
Liabilities and Equity
Revolving credit facilities			848
Long-term debt, due within one year			1,005
Accrued interest			288
Accounts payable and other accrued liabilities			382
Derivative instruments			711
Other current liabilities			414
Total current liabilities			3,648
Long-term debt			2,504
Liabilities subject to compromise			2,788
Derivative instruments			135
Postretirement benefit obligations			(1)
Asset retirement obligations and accrued environmental costs			580
Deferred income taxes			82
Other noncurrent liabilities			19
Total Liabilities			9,755
Total Stockholders' Equity			(818)
Noncontrolling interests			124
Total Equity			(694)
Total Liabilities and Equity			9,061
Reorganization Adjustments
Assets
Cash and cash equivalents			(1,133)
Restricted cash and cash equivalents			426
Accounts receivable, net			(3)
Inventory, net			0
Derivative instruments			0
Other current assets			0
Total current assets			(710)
Property, plant and equipment, net (Note 10)			0
Nuclear decommissioning trust funds (Notes 9 and 14)			0
Derivative instruments			0
Other noncurrent assets			(12)
Total Assets			(722)
Liabilities and Equity
Revolving credit facilities			(848)
Long-term debt, due within one year			(1,000)
Accrued interest			(284)
Accounts payable and other accrued liabilities			3
Derivative instruments			0
Other current liabilities			(349)
Total current liabilities			(2,478)
Long-term debt			281
Liabilities subject to compromise			(2,788)
Derivative instruments			0
Postretirement benefit obligations			302
Asset retirement obligations and accrued environmental costs			202
Deferred income taxes			283
Other noncurrent liabilities	60		60
Total Liabilities			(4,138)
Total Stockholders' Equity	$ 3,416		3,416
Noncontrolling interests			0
Total Equity			3,416
Total Liabilities and Equity			(722)
Fresh Start Adjustments
Assets
Cash and cash equivalents			0
Restricted cash and cash equivalents			(81)
Accounts receivable, net			0
Inventory, net			(141)
Derivative instruments			(632)
Other current assets			(5)
Total current assets			(859)
Property, plant and equipment, net (Note 10)			(458)
Nuclear decommissioning trust funds (Notes 9 and 14)			0
Derivative instruments			(37)
Other noncurrent assets			74
Total Assets			(1,280)
Liabilities and Equity
Revolving credit facilities			0
Long-term debt, due within one year			0
Accrued interest			0
Accounts payable and other accrued liabilities			0
Derivative instruments			(654)
Other current liabilities			3
Total current liabilities			(651)
Long-term debt			55
Liabilities subject to compromise			0
Derivative instruments			(93)
Postretirement benefit obligations			34
Asset retirement obligations and accrued environmental costs			(340)
Deferred income taxes			(8)
Other noncurrent liabilities			14
Total Liabilities			(989)
Total Stockholders' Equity			(277)
Noncontrolling interests			(14)
Total Equity			(291)
Total Liabilities and Equity			$ (1,280)

Supplemental Cash Flow Information (Tables)

12 Months Ended

Dec. 31, 2024

Supplemental Cash Flow Elements [Abstract]

Schedule of Supplemental Consolidated Statements of Cash Flows

Supplemental information for the Consolidated Statements of Cash Flows for the periods was:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Cash paid during the period
Interest and other finance charges, net of capitalized interest (a)	$	255	$	133	$	283	$	277
Income taxes, net	20		12		7		14

Unrealized (gain) loss on derivative instruments included on the Statements of Cash Flows
Commodity contracts	$	(62)	$	(52)	$	63	$	(625)
Interest rate swap contracts (interest expense)	(7)		12		2		(23)
Unrealized (gain) loss on derivative instruments	$	(69)	$	(40)	$	65	$	(648)

Depreciation, amortization and accretion included on the Statements of Cash Flows
Depreciation, amortization and accretion	$	298	$	165	$	200	$	520

Other	(13)		(8)		8		29
Depreciation, amortization and accretion	$	285	$	157	$	208	$	549

Reconciliation of other non-cash operating activities

Bitcoin revenue	$	(91)	$	(81)	$	(27)	$	—
Stock-based compensation	33		19		—		—
Fair value adjustment on distribution of miners	14		—		—		—
Derivative option premium amortization	11		52		29		67
Derivatives with financing elements	—		—		—		104
Non-cash environmental liability revisions	—		—		—		13






Other	7		17		5		16
Total	$	(26)	$	7	$	7	$	200

Non-cash investing activities
Capital expenditure accrual increase (decrease)	$	6	$	7	$	(28)	2
Accounts receivable contributed to equity method investment	—		—		—		2

Non-cash financing activities
Non-cash increase to PP&E and decrease to other current assets for contribution of Bitcoin miners to Nautilus (b)	$	—	$	—	$	14	$	30
Non-cash decrease to PP&E and decrease to noncontrolling interest for distribution of Bitcoin miners to TeraWulf (c)	43		—		3		—
Non-cash increase to PP&E and increase to noncontrolling interest for contribution of Bitcoin miners by TeraWulf (b)	—		—		38		14

__________________

(a)Capitalized interest totaled $5 million for the year ended December 31, 2024 (Successor); $10 million for the period from May 18 through December 31, 2023 (Successor); and $12 million for the period from January 1 through May 17, 2023 (Predecessor), and $12 million for the year ended December 31, 2022 (Predecessor).

(b)In 2023, each of the joint venture partners of Nautilus made non-cash contributions to Nautilus of Bitcoin miners that increased PP&E.

(c)In 2024, Nautilus distributed Bitcoin miners to TeraWulf as part of the buyout of TeraWulf’s noncontrolling interest.

The following provides a reconciliation of “Cash and cash equivalents” and “Restricted cash and cash equivalents” presented on the Consolidated Statements of Cash Flows to line items within the Consolidated Balance Sheets:


	Successor
	December 31, 2024		December 31, 2023
Cash and cash equivalents	$	328	$	400

Restricted cash and cash equivalents:
TES TLC debt restricted deposits	—		472
Nautilus project restricted deposits	—		10
Commodity exchange margin deposits	37		—
Cumulus Digital restricted deposits	—		19
Restricted cash and cash equivalents	37		501
Total	$	365	$	901

Acquisitions and Divestitures	12 Months Ended
Acquisitions and Divestitures	Dec. 31, 2024
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]
Acquisitions and Divestitures	20. Acquisitions and Divestitures 2024 Activities ERCOT Sale. In May 2024, we sold our 1,710 MW Texas generation portfolio to CPS Energy for $785 million, subject to customary net working capital adjustments. A gain on sale of $564 million is presented as “Gain (loss) on sale of assets, net” on the Consolidated Statements of Operations for the year ended December 31, 2024 (Successor). AWS Data Campus Sale. In March 2024, AWS purchased substantially all the assets related to the AWS Data Campus and certain other assets for gross proceeds of $650 million, of which $350 million were received at closing with the remaining $300 million held in escrow until August 2024. For the year ended December 31, 2024 (Successor), a $324 million gain on sale is presented as “Gain (loss) on sale of assets, net” on the Consolidated Statements of Operations. In connection with the AWS Data Campus Sale, the Company entered into the AWS PPA. 2023 Activities Western Gas Book Divestiture. In April 2023, Talen sold certain contracts relating to the transportation of natural gas in the southwestern United States for $15 million. For the period from January 1 through May 17, 2023 (Predecessor), a $15 million gain was presented as “Gain (loss) on sale of assets, net” on the Consolidated Statements of Operations. Pennsylvania Minerals Divestiture. In March 2023, Talen sold certain mineral interests located in Pennsylvania for $29 million, while preserving the right to certain royalty payments from existing and future producing natural gas wells. For the period from January 1 through May 17, 2023 (Predecessor), a $29 million gain was presented as “Gain (loss) on sale of assets, net” on the Consolidated Statements of Operations.

Long-term Debt and Other Credit Facilities - Summary of Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2024	Jun. 30, 2024	Dec. 31, 2023	May 17, 2023
Debt Instrument [Line Items]
Total principal	$ 3,038		$ 2,849
Unamortized deferred financing costs and original issuance discounts	(34)		(29)
Total	3,004		2,820
Long-term debt, due within one year (Notes 13 and 14)	17		9	$ 5
Long-term debt	$ 2,987		2,811	2,840
Secured Notes
Debt Instrument [Line Items]
Interest rate	8.625%
Total principal	$ 1,200		1,200	1,200
TLB-1 \| Secured Debt
Debt Instrument [Line Items]
Interest rate	7.02%
Total principal	$ 857		866	580
TLB-2 \| Secured Debt
Debt Instrument [Line Items]
Interest rate	7.02%
Total principal	$ 850		0
TLC \| Secured Debt
Debt Instrument [Line Items]
Total principal	$ 0		470	$ 470
PEDFA 2009B Bonds \| Bonds
Debt Instrument [Line Items]
Interest rate	5.25%	5.25%
Total principal	$ 50	$ 50	50
PEDFA 2009C Bonds \| Bonds
Debt Instrument [Line Items]
Interest rate	5.25%	5.25%
Total principal	$ 81	$ 81	81
Cumulus Digital TLF \| Line of Credit
Debt Instrument [Line Items]
Total principal	$ 0		$ 182

Asset Retirement Obligations and Accrued Environmental Costs - Schedule of Asset Retirement Obligations (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023	Dec. 31, 2022
Asset Retirement Obligation [Line Items]
Asset retirement obligations	$ 498	$ 464	$ 766	$ 751
Nuclear fuel
Asset Retirement Obligation [Line Items]
Asset retirement obligations	242	214
Non-Nuclear
Asset Retirement Obligation [Line Items]
Asset retirement obligations	$ 256	$ 250

Fresh Start Accounting (Tables)

12 Months Ended

Dec. 31, 2024

Plan of Reorganization [Abstract]

Reorganization, Chapter 11

The following table reconciles the Company’s enterprise value to the estimated reorganization value at Emergence:


	May 17, 2023
Enterprise value (a)	$	4,500
Plus: Cash and cash equivalents and Restricted cash and cash equivalents (b)	701
Plus: Current liabilities excluding long-term debt due within one year	514
Plus: Non-current liabilities excluding long-term debt and liability-classified warrants	1,234
Plus: Fair value of noncontrolling interest	110
Reorganization value to be allocated	$	7,059

__________________

(a)Excludes any value associated with noncontrolling interest.

(b)Excludes $52 million for payment of professional fees.

The following table reconciles TES’s enterprise value to the estimated fair value at Emergence:


	May 17, 2023
Enterprise value (a)	$	4,500
Plus: Cash and cash equivalents and Restricted cash and cash equivalents (b)	701
Less: Fair value of debt	(2,845)
Less: Liability-classified warrants	(35)
Fair value of member’s equity (c)	2,321
Plus: Fair value of noncontrolling interest	110
Fair value of equity	$	2,431

__________________

(a)Excludes any value associated with noncontrolling interest.

(b)Excludes $52 million for payment of professional fees.

(c)Issued in accordance with the Plan of Reorganization. Includes 59,028,843 shares of TEC common stock and $8 million of equity-classified warrants.


	May 17, 2023
Assets	Predecessor		Reorganization Adjustments (a)			Fresh Start Adjustments			Successor
Cash and cash equivalents	$	1,302	$	(1,133)	(b)	$	—		$	169
Restricted cash and cash equivalents	240		426		(c)	(81)		(q)	585
Accounts receivable, net	148		(3)		(d)	—			145
Inventory, net	448		—			(141)		(r)	307
Derivative instruments	818		—			(632)		(q)	186
Other current assets	135		—			(5)		(s)	130
Total current assets	3,091		(710)			(859)			1,522
Property, plant and equipment, net	4,322		—			(458)		(t)	3,864
Nuclear decommissioning trust funds	1,465		—			—			1,465
Derivative instruments	37		—			(37)		(q)	—
Other noncurrent assets	146		(12)		(e)	74		(u)	208
Total Assets	$	9,061	$	(722)		$	(1,280)		$	7,059

Liabilities and Equity
Revolving credit facilities	$	848	$	(848)	(f)	$	—		$	—
Long-term debt, due within one year	1,005		(1,000)		(g)	—			5
Accrued interest	288		(284)		(h)	—			4
Accounts payable and other accrued liabilities	382		3		(i)	—			385
Derivative instruments	711		—			(654)		(q)	57
Other current liabilities	414		(349)		(j)	3		(v)	68
Total current liabilities	3,648		(2,478)			(651)			519
Long-term debt	2,504		281		(k)	55		(w)	2,840
Liabilities subject to compromise	2,788		(2,788)		(l)	—			—
Derivative instruments	135		—			(93)		(q)	42
Postretirement benefit obligations	(1)		302		(m)	34		(x)	335
Asset retirement obligations and accrued environmental costs	580		202		(m)	(340)		(y)	442
Deferred income taxes	82		283		(n)	(8)		(z)	357
Other noncurrent liabilities	19		60		(o)	14		(aa)	93
Total Liabilities	9,755		(4,138)			(989)			4,628
Member’s equity	(818)		3,416		(p)	(277)		(bb)	2,321
Noncontrolling interests	124		—			(14)		(cc)	110
Total Equity	(694)		3,416			(291)			2,431
Total Liabilities and Equity	$	9,061	$	(722)		$	(1,280)		$	7,059

The reorganization adjustments required in connection with the application of fresh start accounting and the allocation of the enterprise value were:

(b)The uses of “Cash and cash equivalents” at Emergence resulting from the implementation of the Plan of Reorganization were:


Proceeds from rights offering	$	1,400
Proceeds from TLB-1 and TLC	1,019
Proceeds from Secured Notes	1,200
Release of restricted cash	89
Payment of claims under prepetition senior secured revolving credit facility	(1,029)
Payment of claims under other prepetition secured indebtedness	(2,136)
Payment of debtor-in-possession term loan	(1,012)
Restriction of cash relating to TLC LCF	(470)
Payment of debt issuance costs on exit financing (TLB-1, TLC, and Secured Notes)	(54)
Funding of professional fees escrow account	(52)
Payment of hedge rejections	(42)
Payment to general unsecured creditors trust	(26)
Payment of professional fees	(22)
Other (a)	2
Total uses of Cash and cash equivalents	$	(1,133)

__________________

(a)Includes $1 million of proceeds from Riverstone for payment to general unsecured creditors trust.

(c)“Restricted cash and cash equivalents” net change:


Restriction of cash relating to TLC LCF	$	470
Funding of professional fees escrow account	52
Release of restricted cash	(89)
Payment of professional fees	(7)
Net change in Restricted cash and cash equivalents	$	426

(d)“Accounts receivable, net” net change related to settlement of affiliate receivables.

(e)“Other noncurrent assets” net change:


Write-off of debt issuance costs associated with prepetition senior secured revolving credit facility	$	(22)
Reclassification of previously capitalized debt issuance costs to Long-term debt	(14)
Capitalization of debt issuance costs	24
Net change in Other noncurrent assets	$	(12)

(f)Payment of principal amounts owed under prepetition senior secured revolving credit facility.

(g)Repayment of debtor-in-possession credit facilities.

(h)“Accrued interest” net change:


Payment of accrued interest on prepetition senior secured revolving credit facility	$	(183)
Payment of accrued interest on other prepetition secured indebtedness	(89)
Payment of accrued interest on debtor-in-possession credit facilities	(12)
Net change in Accrued interest	$	(284)

(i)“Accounts payable and other accrued liabilities” net change:


Payment of hedge contract rejections	$	(42)
Payment of professional fees	(6)
Reinstatement of liabilities subject to compromise	38
Accrual for professional fees incurred at Emergence	13
Net change in Accounts payable and other accrued liabilities	$	3

(j)“Other current liabilities” net change:


Issuance of equity for backstop premium	$	(380)
Reinstatement of liabilities subject to compromise	31
Net change in Other current liabilities	$	(349)

(k)“Long-term debt” net change:


Payment of claims under prepetition secured indebtedness	$	(2,048)
Borrowings of $1.2 billion under the Secured Notes (a)	1,179
Borrowings of $580 million under TLB-1 (b)	548
Borrowings of $470 million under TLC (c)	446
Reinstatement of PEDFA 2009B Bonds and PEDFA 2009C Bonds (d)	130
Write-off of prepetition secured indebtedness issuance costs	26
Net change in Long-term debt	$	281

______________

(a)Net of an aggregate initial purchaser discount and debt issuance costs of $21 million.

(b)Net of an aggregate original issue discount and debt issuance costs of $32 million.

(c)Net of an aggregate original issue discount and debt issuance costs of $24 million.

(d)Includes recognition of $4 million of interest expense.

(l)“Liabilities subject to compromise” settled or reinstated at Emergence in accordance with the Plan of Reorganization:


Liabilities subject to compromise prior to Emergence
Debt	$	1,555
Termination of retail contracts	447
Postretirement benefit obligations	305
Asset retirement obligations and accrued environmental costs	220
Other liabilities	92
Deferred tax liabilities	77
Accounts payable and accrued liabilities	51
Accrued interest	41
Total	2,788

Reinstatement and settlements of certain Liabilities subject to compromise
Reinstatement of liabilities subject to compromise (a)	(801)
Excess fair value ascribed to lenders participating in rights offering	(315)
Issuance of member’s equity to holders of claims under prepetition unsecured notes and PEDFA 2009A Bonds	(186)
Payment to general unsecured creditors trust	(24)
Total	(1,326)
Gain on derecognition of certain Liabilities subject to compromise (b)	$	1,462

______________

(a)Primarily includes postretirement benefit obligations, AROs, and deferred income taxes.

(b)Represents liabilities subject to compromise that were discharged in accordance with the Plan of Reorganization.

(m)Reinstatement of “Liabilities subject to compromise.”

(n)“Deferred income taxes” net change:


Increase in deferred tax liabilities primarily due to estimated tax attribute reduction from the recognition of cancellation of debt income, partially offset by change in valuation allowance	$	206
Reinstatement of liabilities subject to compromise	77
Net change in Deferred income taxes	$	283

(o)“Other noncurrent liabilities” net change:


Issuance of liability-classified warrants	$	35
Reinstatement of liabilities subject to compromise	25
Net change in Other noncurrent liabilities	$	60

The estimated fair value of liability-classified warrants was determined using a Black-Scholes Option Pricing Model with the following assumptions at Emergence:


Expected volatility	30		%
Expected term (years)	5
Expected dividend yield	—		%
Risk-free interest rate	3.6		%
Strike price per share	$	52.92
Fair value per share	$	11.29

(p)“Member’s equity” net change:


Gain on settlement of liabilities subject to compromise	$	1,462
Other losses attributable to gain on debt discharge	(3)
Gain on debt discharge	1,459
Write-off of deferred financing cost	(46)
Professional fees expensed at Emergence	(27)
Restructuring-related compensation expense	(8)
Total reorganization items from reorganization adjustments	1,378
Interest expense incurred at Emergence	(4)
Income from reorganization adjustments before income taxes	1,374
Income tax expense	(206)
Net income from reorganization adjustments	1,168
Issuance of member’s equity in connection with rights offering	1,715
Issuance of member’s equity for backstop premium	380
Issuance of member’s equity to holders of claims under prepetition unsecured notes and PEDFA 2009A Bonds	186
Issuance of equity-classified warrants	8
Issuance of liability-classified warrants	(35)
Other (a)	(6)
Net change in Member’s equity	$	3,416

______________

(a)Includes $1 million of proceeds from Riverstone for payment to general unsecured creditors trust.

Fresh Start Adjustments

(q)Net presentation of derivatives on the Consolidated Balance Sheets. See Note 2 for additional information on the related accounting policy.

(r)“Inventory, net” fair value adjustments:


Coal	$	(33)
Oil products	11
Materials and supplies	(133)
Environmental products	14
Total adjustment to Inventory, net	$	(141)

(s)“Other current assets” primarily represents miscellaneous fair value adjustments.

(t)“Property, plant and equipment, net” fair value adjustments:


Electric generation	$	(350)
Other property and equipment	(80)
Intangible assets	(65)
Capitalized software	(3)
Construction work in progress	40
Total adjustment to Property, plant and equipment, net	$	(458)

(u)“Other noncurrent assets” fair value adjustments:


Favorable supply contracts (a)	$	109
Fair value adjustment to equity method investments	3
Eliminate debt issuance costs associated with debtor-in-possession credit facilities	(29)
Fair value reduction to other miscellaneous assets	(9)
Total adjustment to Other noncurrent assets	$	74

__________________

(a)The fair value of supply contracts was determined utilizing the present value of the after-tax difference between the pricing of actual contracts in place and a current market benchmark.

(v)“Other current liabilities” fair value adjustments, primarily related to short-term AROs.

(w)“Long-term debt” fair value adjustments:


Eliminate debt issuance costs associated with prepetition secured notes, prepetition TLB and LMBE-MC TLB	$	48
Fair value adjustment to Cumulus Digital TLF	11
Fair value adjustment to LMBE-MC TLB	(4)
Total adjustment to Long-term debt	$	55

Fair value adjustments to “Long-term debt” were determined using a lattice model, given that the debt can be prepaid by the borrower prior to the maturity date.

(x)Change in accounting policy for discount rates used to estimate postretirement obligations from a bond-matching model to yield curve approach. See Note 2 for additional information.

(z)Adjustment to “Deferred income taxes” for the change in financial reporting basis of assets and liabilities as a result of the adoption of fresh start accounting.

(bb)Cumulative impact of fresh start accounting adjustments presented herein.

(cc)“Noncontrolling interests” fair value adjustments for certain subsidiaries


	Predecessor
	December 31, 2022
Debt (a)	$	1,558
Termination of retail power and other contracts	447
Postretirement benefit obligations (a)	309
Asset retirement obligations and accrued environmental costs (a)	219
Other liabilities (a)	114
Deferred tax liabilities	83
Accounts payable and accrued liabilities	53
Accrued interest	41
Derivatives (a)	1
Liabilities Subject to Compromise	$	2,825

__________________

(a)Includes both current and noncurrent amounts.

“Reorganization income (expense), net” for the relevant periods were:


	Predecessor
	January 1 through May 17, 2023		Year Ended December 31, 2022
Backstop premium	$	(70)	$	(310)
Gain (loss) on debt discharge	1,459		—
Gain (loss) on revaluation adjustments	(460)		—
Professional fees	(56)		(210)
Make-whole premiums and accrued interest on certain indebtedness	(21)		(183)
Professional fees incurred to obtain the debtor-in-possession credit facilities	—		(70)
Write-off of deferred financing cost and original issue discount	(46)		(30)
Other	(7)		(9)
Reorganization Income (Expense), net	$	799	$	(812)

Stockholders' Equity - Changes in AOCI (Details) - USD ($)
$ in Millions

5 Months Ended

7 Months Ended

12 Months Ended

May 17, 2023

Dec. 31, 2023

Dec. 31, 2024

Dec. 31, 2022

AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]

Beginning balance

$ 2,431

$ 2,534

Other comprehensive income (loss)

$ 6

(23)

$ (15)

Cancellation of equity at Emergence

^[1]

Ending balance

2,431

2,534

1,387

Accumulated other comprehensive income (loss)

AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]

Beginning balance

(167)

(23)

(152)

Gains (losses) arising during the period

(36)

(84)

Reclassifications to Consolidated Statements of Operations

Income tax benefit (expense)

(5)

(1)

Other comprehensive income (loss)

(23)

(15)

Cancellation of equity at Emergence

161

Ending balance

$ 0

$ (23)

$ (12)

$ (167)

[1]	Pursuant to the Plan of Reorganization: (i) existing equity interests were canceled; and (ii) new equity interests and equity-classified warrants were issued.

- Definition

Amount after tax and reclassification adjustments of other comprehensive income (loss).

+ References

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+ Details

- Definition

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

+ References

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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482765/220-10-50-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481674/830-30-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481694/830-30-45-17

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 20
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481694/830-30-45-20

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(19))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-10

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482659/740-20-45-11

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(21))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(23))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482659/740-20-45-2

+ Details

- Definition

Amount of equity (deficit) attributable to parent and noncontrolling interest. Excludes temporary equity.

+ References

+ Details

Property, Plant, and Equipment - Narrative (Details) - USD ($)	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022	Jan. 01, 2025	Jan. 31, 2020
Property, Plant and Equipment [Line Items]
Aggregate fuel purchases	$ 14,000,000	$ 23,000,000	$ 35,000,000	$ 63,000,000
Discount rate			11.00%
Impairments (Note 10)	381,000,000	3,000,000	$ 1,000,000	$ 0
Nuclear fuel
Property, Plant and Equipment [Line Items]
Amortization of nuclear fuel intangible assets		53,000,000	33,000,000
Carrying Value		$ 56,000,000	$ 23,000,000
Susquehanna
Property, Plant and Equipment [Line Items]
Ownership interest		90.00%	90.00%
Conemaugh
Property, Plant and Equipment [Line Items]
Ownership interest			22.22%
Keystone
Property, Plant and Equipment [Line Items]
Ownership interest			12.34%
Talen Montana
Property, Plant and Equipment [Line Items]
Ownership interest			15.00%
Talen Montana \| Colstrip Unit 3
Property, Plant and Equipment [Line Items]
Ownership interest			30.00%
Percentage of operating costs and expenditures			15.00%
Talen Montana \| Colstrip Unit 4
Property, Plant and Equipment [Line Items]
Percentage of operating costs and expenditures			15.00%
Talen Montana \| Colstrip Unit 1
Property, Plant and Equipment [Line Items]
Percentage of decommissioning and other related costs						50.00%
Talen Montana \| Colstrip Unit 2
Property, Plant and Equipment [Line Items]
Percentage of decommissioning and other related costs						50.00%
Property, Plant, and Equipment, Brandon Shores
Property, Plant and Equipment [Line Items]
Impairments (Note 10)	$ 361,000,000
Property, Plant, and Equipment, Brandon Shores \| Subsequent Event
Property, Plant and Equipment [Line Items]
Fixed-cost monthly payments					$ 12,083,333
Fixed-cost per day payments					312
Property, Plant, And Equipment, Wagner \| Subsequent Event
Property, Plant and Equipment [Line Items]
Fixed-cost monthly payments					2,916,667
Fixed-cost per day payments					$ 137

Consolidated Statements of Equity - USD ($)
$ in Millions

Total

Cumulus Digital Holdings

^[6]

TeraWulf

^[7]

Common stock shares

Additional paid-in capital

Accumulated earnings (deficit)

Accumulated other comprehensive income (loss)

Treasury Stock

Member's Equity

Non controlling Interest

Cumulus Digital Holdings

^[6]

Non controlling Interest

TeraWulf

^[7]

Beginning balance at Dec. 31, 2021

$ (152)

Member's Equity, Beginning balance at Dec. 31, 2021

$ 733

$ 0

Increase (Decrease) in Stockholders' Equity [Roll Forward]

Net income (loss)

(1,293)

(1,289)

(4)

Other comprehensive income (loss)

(15)

Non-cash consolidation of affiliate subsidiary

Cancellation of equity at Emergence

Cash contribution

Non-cash distribution to member

(2)

Non-cash contribution from member

Ending balance at Dec. 31, 2022

(167)

Member's Equity, Ending balance at Dec. 31, 2022

(482)

(573)

Increase (Decrease) in Stockholders' Equity [Roll Forward]

Net income (loss)

465

479

(14)

Other comprehensive income (loss)

Cancellation of equity at Emergence

^[1]

161

^[1]

Issuance of member’s equity

^[1]

2,313

Issuance of warrants

^[1]

Common equity from member's equity exchange (in shares)

^[2]

59,029,000

Common equity from member's equity exchange

$ 2,321

$ (2,321)

Non-cash distribution to member

^[3]

(5)

Non-cash contribution from member

^[4]

Ending balance at May. 17, 2023

$ 2,431

2,321

$ 0

110

Ending balance (in shares) at May. 17, 2023

59,028,843

59,029,000

^[2]

Increase (Decrease) in Stockholders' Equity [Roll Forward]

Net income (loss)

$ 143

134

Other comprehensive income (loss)

(23)

Cancellation of equity at Emergence

Purchase of noncontrolling interest

^[5]

(19)

(24)

Non-cash distribution to member

^[3]

(20)

Cash contribution

Stock-based compensation expense

Other

Ending balance at Dec. 31, 2023

$ 2,534

2,346

134

(23)

Ending balance (in shares) at Dec. 31, 2023

59,028,843

59,029,000

^[2]

Increase (Decrease) in Stockholders' Equity [Roll Forward]

Net income (loss)

$ 1,013

998

Other comprehensive income (loss)

$ 11

Cancellation of equity at Emergence

Share repurchase (in shares)

(13,227,222)

(13,227,000)

^[2]

Share repurchases

$ (1,977)

(1,977)

Purchase of noncontrolling interest

^[5]

(125)

(87)

(38)

Retirement of treasury stock

(519)

(1,458)

1,977

Cash settlement of restricted stock units

(32)

Exercise of warrants (in shares)

^[2]

160,000

Exercise of warrants

(16)

Non-cash distribution to member

$ (2)

$ (52)

$ (2)

$ (52)

Stock-based compensation expense

Ending balance at Dec. 31, 2024

$ 1,387

$ 1,725

$ (326)

$ (12)

$ 0

Ending balance (in shares) at Dec. 31, 2024

45,961,910

45,962,000

^[2]

[1]	Pursuant to the Plan of Reorganization: (i) existing equity interests were canceled; and (ii) new equity interests and equity-classified warrants were issued.
[2]	Shares in thousands.
[3]	Related primarily to distributions of Bitcoin to TeraWulf.
[4]	Related to contributions of cryptocurrency miners by TeraWulf to Nautilus.
[5]	TES acquisition of remaining noncontrolling interests in Cumulus Digital and Nautilus. See Note 18 for additional information.
[6]	Distributions to noncontrolling interest owners of Cumulus Digital and Nautilus.
[7]	Related primarily to distribution of Bitcoin and cryptocurrency miners to TeraWulf.

Postretirement Benefit Obligations - Schedule of Net Benefit Costs (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Net periodic benefit costs (credits):
Net periodic defined benefit cost (credit)	$ (3)	$ 2	$ 14	$ 12
Net actuarial (gain) loss	0	38	(5)	15
Prior service credit	0	0	(21)	0
Reclassifications due to settlement and (or) curtailment:
Amortization of prior service cost (credit)	0	0	1	(1)
Amortization of net (gain) loss	(2)	0	0	(27)
Pension Benefits
Net periodic benefit costs (credits):
Service cost	1	2	2	4
Interest cost	25	40	63	50
Expected return on plan assets	(30)	(41)	(66)	(68)
Amortization of net (gain) loss	2	0	0	27
Resolved litigation settlement and other charges	0	1	15	0
Net periodic defined benefit cost (credit)	(2)	2	14	13
Net actuarial (gain) loss	2	38	(3)	19
Reclassifications due to settlement and (or) curtailment:
Amortization of net (gain) loss	0	0	0	(27)
Total recognized in OCI	2	38	(3)	(8)
Total recognized in net periodic costs and OCI	$ 0	$ 40	$ 11	$ 5
Assumptions
Rate of compensation increase	3.45%	3.45%	3.45%	3.45%
Expected return on plan assets	7.50%	7.25%	7.25%	5.75%
Pension Benefits \| Pension Plan, Periodic Benefit Costs
Assumptions
Discount rate	5.41%	5.12%	5.00%	2.97%
Other Postretirement Benefits
Net periodic benefit costs (credits):
Service cost	$ 1	$ 1	$ 1	$ 1
Interest cost	1	2	3	3
Expected return on plan assets	(2)	(2)	(4)	(4)
Amortization of prior service cost (credit)	0	0	(1)	(1)
Net periodic defined benefit cost (credit)	0	1	(1)	(1)
Net actuarial (gain) loss	0	(1)	(2)	(3)
Prior service credit	0	0	(21)	0
Reclassifications due to settlement and (or) curtailment:
Amortization of prior service cost (credit)	0	0	1	1
Amortization of net (gain) loss	0	0	0	(1)
Total recognized in OCI	0	(1)	(22)	(3)
Total recognized in net periodic costs and OCI	$ 0	$ 0	$ (23)	$ (4)
Assumptions
Rate of compensation increase	2.31%	2.31%	2.31%	2.31%
Expected return on plan assets	5.74%	5.49%	5.49%	3.89%
Health care grading trend rates				4.50%
Other Postretirement Benefits \| Other Postretirement Benefit Plan, Periodic Benefit Costs
Assumptions
Discount rate	5.41%	5.13%	5.01%	2.94%
Other Postretirement Benefits \| Minimum
Assumptions
Health care grading trend rates	6.50%	6.50%	7.10%
Other Postretirement Benefits \| Maximum
Assumptions
Health care grading trend rates	4.50%	4.50%	4.40%

Nuclear Decommissioning Trust Funds - Summary of the Sale Proceeds, Gains, and Losses for Available-for-Sale Debt Securities (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Sales proceeds of NDT funds investments	$ 839	$ 1,259	$ 2,132	$ 2,081
Gross realized gains	7	5	12	10
Gross realized losses	$ (12)	$ (11)	$ (13)	$ (43)

Insider Trading Policies and Procedures	12 Months Ended
Insider Trading Policies and Procedures	Dec. 31, 2024
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

Nuclear Decommissioning Trust Funds

12 Months Ended

Dec. 31, 2024

Investments, Debt and Equity Securities [Abstract]

Nuclear Decommissioning Trust Funds

9. Nuclear Decommissioning Trust Funds


	Successor
	December 31, 2024								December 31, 2023
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value		Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Cash equivalents	$	3	$	—	$	—	$	3	$	9	$	—	$	—	$	9
Equity securities	509		651		55		1,105		491		575		53		1,013
Debt securities	615		3		7		611		570		10		1		579
Receivables (payables), net	5		—		—		5		(26)		—		—		(26)
NDT funds	$	1,132	$	654	$	62	$	1,724	$	1,044	$	585	$	54	$	1,575

See Note 14 for additional information on the NDT fair value. There were no available-for-sale debt securities with credit losses as of December 31, 2024 (Successor) and December 31, 2023 (Successor).

As of December 31, 2024 (Successor), there was no intent to sell available-for-sale debt securities with unrealized losses, and it is not more likely than not that each of these investments will be required to be sold before the recovery of its amortized cost. The aggregate related fair value of available-for-sale debt securities with unrealized losses as of December 31, 2024 (Successor) were:


	Fair Value		Unrealized Losses
Corporate debt securities	$	71	$	(2)
Municipal debt securities	60		(1)
U.S. Government debt securities	226		(4)
Debt securities in unrealized loss position	$	357	$	(7)

As of December 31, 2024 (Successor), the aggregate fair value of debt securities in a loss position for a duration of one year or longer were $15 million and the unrealized losses were non-material.

The contractual maturities for available-for-sale debt securities presented on the Consolidated Balance Sheets were:


	Successor
	December 31, 2024		December 31, 2023
Maturities within one year	$	82	$	105
Maturities within two to five years	220		194
Maturities thereafter	309		280
Debt securities, fair value	$	611	$	579

The sales proceeds, gains, and losses for available-for-sale debt securities for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Sales proceeds of NDT funds investments (a)	$	2,132	$	1,259	$	839	$	2,081
Gross realized gains	12		5		7		10
Gross realized losses	(13)		(11)		(12)		(43)

__________________

(a)Sales proceeds are used to pay income taxes and trust management fees. Remaining proceeds are reinvested in the NDT.

- Definition

The entire disclosure for investments owned by investment company.

+ References + Details

Property, Plant, and Equipment

12 Months Ended

Dec. 31, 2024

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

10. Property, Plant and Equipment


		Successor
		December 31, 2024						December 31, 2023
	Estimated Useful Life (years)	Gross Value		Accumulated Depreciation		Carrying Value		Gross Value		Accumulated Depreciation		Carrying Value
Electric generation	3-27	$	3,030	$	(292)	$	2,738	$	3,178	$	(109)	$	3,069
Nuclear fuel	1-6	322		(152)		170		228		(55)		173
Other property and equipment	1-26	90		(18)		72		358		(21)		337

Capitalized software	1-5	8		(3)		5		6		(1)		5
Construction work in progress		169		—		169		255		—		255
Property, plant and equipment, net		$	3,619	$	(465)	$	3,154	$	4,025	$	(186)	$	3,839

The components of “Depreciation, amortization and accretion” presented on the Consolidated Statements of Operations for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Depreciation expense (a)	$	225	$	133	$	173	$	432
Amortization expense (b)	16		1		4		12
Accretion expense (c)	57		31		24		78
Other	—		—		(1)		(2)
Depreciation, amortization and accretion	$	298	$	165	$	200	$	520

__________________

(a)Electric generation and other property and equipment.

(b)Intangible assets and capitalized software.

(c)ARO and accrued environmental cost accretion. See Note 11 for additional information.

The cost of nuclear fuel and the amortization of nuclear fuel intangible assets are presented as “Nuclear fuel amortization” on the Consolidated Statements of Operations.

Amortization expense related to nuclear fuel intangible assets was $33 million for the year ended December 31, 2024 (Successor) and $53 million for the period from May 18 through December 31, 2023 (Successor). Estimated intangible assets amortization expense for the next four years is:


	2025		2026		2027		2028 (a)
Estimated amortization expense	$	14	$	5	$	3	$	1

__________________

(a)Supply contracts underlying the nuclear fuel intangible assets expire in 2028.

The carrying value of nuclear fuel intangible assets presented as “Other noncurrent assets” on the Consolidated Balance Sheets was $23 million as of December 31, 2024 (Successor) and $56 million as of December 31, 2023 (Successor).

Jointly Owned Facilities

Certain of Talen's subsidiaries own undivided interests in jointly owned electric generation facilities and related assets. These generation facilities and other assets are maintained and operated pursuant to their joint ownership participation and operating agreements. Under such arrangements, each participant is responsible for funding its proportional share of costs and is entitled to its proportionate share of electric generation and (or) other attributes of the relevant jointly owned facilities. Talen's proportional share of gross margin and other operating costs for its undivided interests is presented within the Consolidated Statements of Operations.

Talen owns undivided interest of 90% in Susquehanna, 22.22% in Conemaugh, and 12.34% in Keystone. See below for information regarding the ownership of Colstrip in Montana. The carrying value of Colstrip, Conemaugh, and Keystone were non-material as of December 31, 2024 (Successor) and December 31, 2023 (Successor).

The proportionate share of “Property, plant and equipment, net” related to Susquehanna presented on the Consolidated Balance Sheets was:


	Successor
	December 31, 2024		December 31, 2023
Ownership interest	90%		90%

Electric generation	$	2,206	$	2,187
Nuclear fuel	322		228
Other property and equipment	25		19
Capitalized software	2		2

Construction work in progress	109		95
Proportionate property, plant and equipment, cost	2,664		2,531
Less: accumulated depreciation and amortization	326		121
Proportionate property, plant and equipment, net	$	2,338	$	2,410

Talen Montana. Talen Montana owns 30% of Colstrip Unit 3 and does not own any portion of Colstrip Unit 4. However, it is a participant in a joint-owner sharing agreement which governs each party’s responsibilities and rights whereby Talen Montana is responsible for 15% of the total operating costs and expenditures of Colstrip Unit 3 and 15% of Colstrip Unit 4. Accordingly, it is entitled to 15% of the available generation from each of these units. In January 2020, Talen Montana and the other co-owner of Colstrip Units 1 and 2 permanently retired the units. Talen Montana is responsible for 50% of the decommissioning and other related costs of Colstrip Units 1 and 2.

Reliability Impact Assessments

Brandon Shores and H.A Wagner RMR Arrangements. In 2023, we notified PJM of our intent to deactivate electric generation at both our Brandon Shores and H.A. Wagner facilities on June 1, 2025. However, PJM subsequently notified us that both Brandon Shores and H.A Wagner are needed past their previously planned retirement dates to maintain reliability in PJM. In January 2025, we reached a settlement (which remains subject to FERC approval) with key stakeholders on the terms of an RMR arrangement and filed with FERC the resulting Joint Offers of Settlement regarding both facilities’ RMR Continuing Operations Rates Schedules (the “CORS”). If approved, the proposed RMR arrangements will extend the operating life of these plants through May 31, 2029, or until such time as the necessary transmission upgrades are placed into service. Beginning June 1, 2025, the CORS will provide a monthly fixed-cost payment of $12,083,333 ($312/MW-day) for Brandon Shores and $2,916,667 ($137/MW-day) for H.A Wagner, which includes a performance “hold back” of $416,667 per month for Brandon Shores and $208,333 per month for H.A Wagner, each to be paid out based on unit performance. We will also receive separate reimbursement for variable costs and approved project investments.

2023 Impairment

Brandon Shores Asset Group. Brandon Shores is required by contract and permit to cease coal combustion by December 31, 2025. In the first quarter 2023, Talen canceled its plan to convert Brandon Shores to an oil combustion facility due to an increase in expected conversion costs. This decision triggered a recoverability assessment of the carrying value of the Brandon Shores asset group. Brandon Shores notified PJM that it will deactivate electric generation on June 1, 2025. See above for additional information.

The recoverability analysis indicated that the Brandon Shores asset group carrying value exceeded its future estimated undiscounted cash flows, which required an impairment charge to amend the asset group’s carrying value of its PP&E to its estimated fair value. The estimated fair value of the asset group was determined by a discounted cash flow technique that utilized significant unobservable inputs including an 11% discount rate. We believe that the utilized discount rate and other discounted cash flow assumptions are consistent with those used by principal market participants. Such assumptions consider available evidence regarding the prospects of future cash flows for the Brandon Shores asset group, including but not limited to estimated available future generation volumes and useful lives, capacity prices, energy prices, operating costs, capital expenditures, and environmental costs. Accordingly, for the period from January 1 through May 17, 2023 (Predecessor), a $361 million non-cash pre-tax impairment charge on the asset group’s undepreciated PP&E is presented as “Impairments” on the Consolidated Statements of Operations.

Equity Method Investments

Talen holds equity interests in Conemaugh Fuels and Keystone Fuels equal to its respective undivided ownership interests in Conemaugh and Keystone. Conemaugh Fuels and Keystone Fuels were formed to purchase coal and sell it to Conemaugh and Keystone. Additionally, they may sell coal to any entity that manufactures or produces synthetic fuel from coal for resale to Conemaugh and Keystone. The aggregate affiliated fuel purchases by Talen from Conemaugh Fuels and Keystone Fuels is presented as “Fuel and energy purchases” on the Consolidated Statements of Operations. Talen’s aggregate fuel purchases for Conemaugh and Keystone Fuels were $35 million for the year ended December 31, 2024 (Successor), $23 million for the period from May 18 through December 31, 2023 (Successor) and $14 million for the period from January 1 through May 17, 2023 (Predecessor). For the year ended December 31, 2022 (Predecessor), Talen’s aggregate fuel purchases were $63 million.

Revenue - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction (Details) $ in Millions	Dec. 31, 2024 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected capacity revenues	$ 478
Remaining performance obligation period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected capacity revenues	$ 281
Remaining performance obligation period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected capacity revenues	$ 3
Remaining performance obligation period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected capacity revenues	$ 1
Remaining performance obligation period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected capacity revenues	$ 0
Remaining performance obligation period	1 year

Revenue - Summary of Components of Operating Revenues (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	$ 478	$ 1,165	$ 1,574	$ 3,209
Realized and unrealized gain (loss) on derivative instruments	732	179	307	(120)
Nuclear PTC	0	0	220	0
Other revenue	0	0	14	0
Operating revenues	1,210	1,344	2,115	3,089
Amount of PTC revenue utilized as a credit against Federal Income Taxes payable			70
Capacity revenues
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	108	133	192	377
Operating revenues	108	133	192	377
Electricity sales and ancillary services, ISO/RTO
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	281	880	1,144	2,534
Physical electricity sales, bilateral contracts, other
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	62	71	147	298
Other revenue from customers
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	$ 27	$ 81	$ 91	$ 0

Stock-Based Compensation - Summary of PSU and RSU Activity (Details)	12 Months Ended
	Dec. 31, 2024 $ / shares shares
Performance stock units
Units
Balance at the beginning of the period (in shares) \| shares	968,793
Granted (in shares) \| shares	4,945
Forfeited (in shares) \| shares	(17,391)
Balance at the end of the period (in shares) \| shares	956,347
Weighted-Average Grant-Date Fair Value
Balance at the beginning of the period (in dollars per share) \| $ / shares	$ 54.35
Granted (in dollars per share) \| $ / shares	96.00
Forfeited (in dollars per share) \| $ / shares	72.75
Balance at the end of the period (in dollars per share) \| $ / shares	$ 54.23
Restricted stock units
Units
Balance at the beginning of the period (in shares) \| shares	845,269
Granted (in shares) \| shares	56,346
Forfeited (in shares) \| shares	(56,594)
Vested (in shares) \| shares	(295,616)
Balance at the end of the period (in shares) \| shares	549,405
Weighted-Average Grant-Date Fair Value
Balance at the beginning of the period (in dollars per share) \| $ / shares	$ 48.46
Granted (in dollars per share) \| $ / shares	121.89
Forfeited (in dollars per share) \| $ / shares	55.01
Vested (in dollars per share) \| $ / shares	48.90
Balance at the end of the period (in dollars per share) \| $ / shares	$ 55.07

Revenue - Narrative (Details)	1 Months Ended
Revenue - Narrative (Details)	Jul. 31, 2024 USD ($) MW
Revenue from Contract with Customer [Abstract]
Megawatts cleared \| MW	6,820
Clearing price (dollars per MW-day) \| $	$ 269.92

Supplemental Cash Flow Information - Supplemental Consolidated Statements of Cash Flows (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Cash paid during the period
Interest and other finance charges, net of capitalized interest	$ 283	$ 133	$ 255	$ 277
Income taxes, net	7	12	20	14
Unrealized (gain) loss on derivative instruments included on the Statements of Cash Flows
Unrealized gain (loss) on commodity contracts	63	(52)	(62)	(625)
Interest rate swap contracts (interest expense)	2	12	(7)	(23)
Unrealized (gain) loss on commodity derivative contracts	65	(40)	(69)	(647)
Unrealized (gain) loss on derivative instruments				(648)
Depreciation, amortization and accretion included on the Statements of Cash Flows
Depreciation, amortization and accretion	(200)	(165)	(298)	(520)
Other	8	(8)	(13)	29
Depreciation, amortization and accretion	208	157	285	549
Reconciliation of other non-cash operating activities
Bitcoin revenue	(27)	(81)	(91)	0
Stock-based compensation	0	19	33	0
Fair value adjustment on distribution of miners	0	0	14	0
Derivative option premium amortization	29	52	11	67
Derivatives with financing elements	0	0	0	104
Non-cash environmental liability revisions	0	0	0	13
Other	5	17	7	16
Other (Note 19)	7	7	(26)	200
Non-cash investing activities
Capital expenditure accrual increase (decrease)	(28)	7	6	2
Accounts receivable contributed to equity method investment	0	0	0	2
Non-cash financing activities
Non-cash increase to PP&E and decrease to other current assets for transfer of miners by Cumulus Coin	14	0	0	30
Non-cash decrease to PP&E and decrease to noncontrolling interest for distribution of Bitcoin miners to TeraWulf	3	0	43	0
Non-cash increase to PP&E and increase to noncontrolling interest for contribution of Bitcoin miners by TeraWulf	38	0	0	14
Capitalized interests	$ 12	$ 10	$ 5	$ 12

Long-term Debt and Other Credit Facilities - Summary of Key Terms Of Indebtedness (Details)	1 Months Ended	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2024 Rate
Secured Notes
Debt Instrument [Line Items]
Interest rate	8.625%	8.625%
Secured Notes \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Debt instrument, percentage of principal amount available for redemption		40.00%
Debt instrument, prepayment penalty percentage		108.625%
Secured Notes \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Debt instrument, percentage of principal amount available for redemption		10.00%
Debt instrument, prepayment penalty percentage		103.00%
Secured Notes \| Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
Debt instrument, percentage of principal amount available for redemption		104.313%
Secured Notes \| Debt Instrument, Redemption, Period Five
Debt Instrument [Line Items]
Debt instrument, percentage of principal amount available for redemption		100.00%
Secured Notes \| Debt Instrument, Redemption, Period Four
Debt Instrument [Line Items]
Debt instrument, prepayment penalty percentage		102.156%
Secured Debt \| TLB-1
Debt Instrument [Line Items]
Interest rate	7.02%	7.02%
Interest rate	2.50%	2.50%
Debt instrument, amortization interest rate		1.00%
Debt instrument, prepayment penalty percentage		1.00%
Secured Debt \| RCF
Debt Instrument [Line Items]
Interest rate	2.00%
Secured Debt \| TLB-2
Debt Instrument [Line Items]
Interest rate	7.02%	7.02%
Debt instrument, prepayment penalty percentage		1.00%
Secured Debt \| Maximum \| TLB-1
Debt Instrument [Line Items]
Debt instrument, leverage-based step-downs, percentage		2.25%
Secured Debt \| Minimum \| TLB-1
Debt Instrument [Line Items]
Debt instrument, leverage-based step-downs, percentage		2.00%
Line of Credit \| RCF
Debt Instrument [Line Items]
Interest rate		2.00%
Line of credit facility, unused capacity, leveraged-based step down percentage		0.25%
Line of credit facility, unused capacity, commitment fee percentage		0.375%
Debt instrument, fronting fee, percentage		0.125%
Line of Credit \| Maximum \| RCF
Debt Instrument [Line Items]
Debt instrument, leverage-based step-downs, percentage		1.75%
Line of Credit \| Minimum \| RCF
Debt Instrument [Line Items]
Debt instrument, leverage-based step-downs, percentage		1.50%
Bonds \| PEDFA 2009B Bonds And PEDFA 2009C Bonds
Debt Instrument [Line Items]
Interest rate	5.25%	5.25%

Long-term Debt and Other Credit Facilities

12 Months Ended

Dec. 31, 2024

Debt Disclosure [Abstract]

Long-term Debt and Other Credit Facilities

13. Long-term Debt and Other Credit Facilities

TES is the borrower/issuer under all the Company’s debt and credit facilities. As of December 31, 2024 (Successor), TES was not in default under any of its debt or credit agreements.

Long-Term Debt


		Successor
	Interest Rate (a)	December 31, 2024		December 31, 2023
TLB-1	7.02 %	$	857	$	866
TLB-2	7.02 %	850		—
TLC (b)	N/A	—		470
Secured Notes	8.63 %	1,200		1,200
PEDFA 2009B Bonds	5.25 %	50		50
PEDFA 2009C Bonds	5.25 %	81		81
Cumulus Digital TLF (b)	N/A	—		182
Total principal		3,038		2,849
Unamortized deferred financing costs and original issuance discounts		(34)		(29)
Total carrying value		3,004		2,820
Less: long-term debt, due within one year		17		9
Long-term debt		$	2,987	$	2,811

__________________

(a)Computed interest rate as of December 31, 2024 (Successor).

(b)See “Recent Transactions” below for additional information on extinguishments of indebtedness.

Long-term debt maturities as of December 31, 2024 (Successor) were:


	2025		2026		2027		2028		2029		Thereafter		Total
Principal debt maturities	$	17	$	17	$	17	$	17	$	17	$	2,952	$	3,038

Revolving Credit and Other Facilities


		Successor
		December 31, 2024
	Maturity	Committed Capacity (a)		Direct Cash Borrowings		LCs Issued		Unused Capacity
RCF	December 2029	$	700	$	—	$	—	$	700
LCF	December 2026	900		—		374		526


Total		$	1,600	$	—	$	374	$	1,226

__________________

(a)RCF committed capacity can be used for direct cash borrowings and (or) LCs.

In December 2024, the TLC LCF and Bilateral LCF were terminated. However, as certain LCs remained outstanding under these facilities pending their transition to the LCF, corresponding backstop LCs were issued under the LCF. As of December 31, 2024 (Successor), the amount of such backstop LCs issued under the LCF were $297 million.

As of December 31, 2023 (Successor): (i) the aggregate LCs issued under the TLC LCF and Bilateral LCF were $478 million; and (ii) LCs issued under TLC LCF were collateralized by $472 million of cash presented as “Restricted cash and cash equivalents” on the Consolidated Balance Sheets. The restricted cash was released in connection with the TLC LCF termination.

See “Recent Transactions–Credit Facilities” below for additional information on LC facility terminations.

Long-Term Debt, Revolving Credit, and Other Facilities

Certain key terms of our indebtedness include:

Secured Notes

TLB-1

TLB-2

RCF

LCF

PEDFA Bonds

Maturity:

June 2030

May 2030

December 2031

December 2029

December 2026

2009B: December 2038

2009C: December 2037

Index:

None

Term SOFR

None

Rate, Applicable Margin, and Amortization:

8.625% per annum fixed rate

No applicable margin

No amortization

2.50% per annum applicable margin; leverage-based step-downs to 2.25% and 2.00%

Amortization 1.00% per annum; paid quarterly

Same as TLB-1

Cash borrowings: 2.00% per annum applicable margin; leverage-based step-downs to 1.75% and 1.50%

LCs: LC fee equal to applicable margin above + fronting fee of 0.125%

Unused commitments: 0.375%; leverage-based step-down to 0.25%

No amortization

LCs: Same as RCF

Unused commitments: Same as RCF

5.25% per annum fixed rate

No applicable margin

No amortization

Prepayment Penalty:

On or after June 1 of the following years: 2026: 104.313%; 2027: 102.156%; 2028 and after: 100%

1.00% to the extent prepaid prior to June 20, 2025 in connection with a repricing transaction

1.00% to the extent prepaid prior to June 13, 2025 in connection with a repricing transaction

None

Prior to June 1, 2026: Par plus a customary “make-whole” premium

On or after June 1, 2026: Par

Credit Agreement. The Credit Agreement governs the RCF, TLB-1, TLB-2, and LCF. The Credit Agreement contains customary negative covenants including but not limited to limitations on incurrence of liens and additional indebtedness, making investments, payment of dividends, and asset sales. The Credit Agreement also contains customary affirmative covenants. Solely with respect to the RCF and LCF, and solely during a compliance period (i.e., when RCF cash borrowings exceed 50% of revolving commitments), the Credit Agreement requires TES’s consolidated first lien net leverage ratio not to exceed 4.25x. This financial covenant does not apply to the TLB-1 or TLB-2. The Credit Agreement also contains customary representations and warranties, events of default, and remedies (including acceleration of amounts due and (or) termination of commitments).

Secured Notes. Interest on the Secured Notes is payable semi-annually on June 1 and December 1 of each year and at maturity. The Secured Notes are subject to customary negative covenants, including but not limited to certain limitations on incurrence of liens and additional indebtedness, making investments, payment of dividends, and transactions involving the Susquehanna assets, but do not contain any financial covenants. The Secured Notes also contain customary affirmative covenants, events of default, and remedies (including acceleration).

PEDFA Bonds. The PEDFA 2009B and 2009C Bonds were issued by the PEDFA on behalf of TES, and TES then received the proceeds under corresponding back-to-back exempt facilities loan agreements with the PEDFA. Corresponding TES unsecured promissory notes for each series contain the applicable principal, interest, and prepayment provisions. The PEDFA Bonds bear interest at a fixed rate until the end of the current term rate period on June 1, 2027, at which time they are subject to mandatory remarketing during which TES may elect a different interest rate mode. Aside from principal amount and final maturity, the terms of the PEDFA 2009B Bonds and 2009C Bonds are substantially identical. The PEDFA Bonds are subject to customary affirmative and negative covenants appropriate for such tax-exempt facilities, including but not limited to limitations on incurrence of liens (but not unsecured indebtedness), and asset sales. The PEDFA Bonds are also subject customary events of default and remedies (including acceleration).

Secured ISDAs. Talen Energy Marketing is party to certain Secured ISDAs, under which TES and the Subsidiary Guarantors provide the applicable counterparties with a first priority lien on and security interest (which ranks pari passu with the liens securing the Credit Facilities and the Secured Notes) in certain assets in lieu of posting collateral in the form of cash equivalents or LCs. The secured obligations under the Secured ISDAs were $17 million as of December 31, 2024 (Successor).

Security Interests, Guarantees, and Cross-Defaults

Secured Obligations. The obligations under the Credit Facilities, Secured Notes, and Secured ISDAs are secured by a first-priority lien on and security interest in substantially all of the assets of TES and the Subsidiary Guarantors. The Subsidiary Guarantors guarantee TES’s obligations under the Credit Facilities and the Secured Notes. TES and the Subsidiary Guarantors guarantee Talen Energy Marketing’s obligations under the Secured ISDAs. The amount for which TES and the Subsidiary Guarantors may be liable is equal to the amount of obligations outstanding under such agreements and may also include unpaid interest, premiums, penalties, and (or) other fees and expenses. An event of default under the Credit Facilities, Secured Notes, or Secured ISDAs, if not cured or waived, may result in a cross acceleration of amounts due and (or) cross termination across all these agreements.

Unsecured Obligations. The PEDFA Bonds are senior unsecured obligations of TES that are effectively subordinated to TES’s secured obligations, including the Credit Facilities, Secured Notes, and Secured ISDAs, to the extent of the value of the assets securing those obligations. Certain of the Subsidiary Guarantors also guarantee TES’s obligations under the PEDFA Bonds. These guarantees are the general unsecured obligations of such Subsidiary Guarantors, rank equally with all of their other senior unsecured indebtedness, and are effectively subordinated to their secured obligations, including guarantees under the Credit Facilities, Secured Notes, and Secured ISDAs, to the extent of the value of the assets securing those obligations.

Recent Transactions

Secured Notes. In January 2025, the indenture governing the Secured Notes was amended to, among other things: (i) modify certain provisions, including certain covenants and related definitions, in order to substantially conform to the corresponding amendments to the Credit Agreement obtained in the December 2024 transactions discussed below; and (ii) waive TES’s right to optionally redeem up to 10% of the Secured Notes at a price of 103% of par prior to June 1, 2025.

Credit Facilities. In December 2024, TES completed several refinancing transactions:

•TLB-2: Issued a new $850 million TLB-2, the proceeds of which were used, together with cash on hand, to repurchase shares of our outstanding common stock from Rubric. See Note 18 for additional information on repurchases of common stock.

•TLB-1: Repriced the existing $857 million TLB-1 to reduce the current interest rate margin by 100 basis points (to SOFR plus 250 basis points, with further leverage-based step downs available) to align pricing with the new TLB-2.

•RCF: Repriced the existing $700 million RCF to reduce the current interest rate margin by 100 basis points (to SOFR plus 200 basis points, with further leverage-based step downs available), increased revolving LC capacity from $475 million to $700 million, and extended the maturity from May 2028 to December 2029.

•LCF: Issued a new $900 million standalone secured LCF to transition LCs from the TLC LCF and Bilateral LCF. LCs issued under the LCF are subject to an LC fee of 2.00% per annum (with leverage-based step downs available) plus a fronting fee of 0.125% per annum.

•TLC/TLC LCF: Repaid in full the $470 million TLC utilizing the restricted cash collateralizing the TLC LCF, and terminated the TLC and associated $470 million TLC LCF.

•Bilateral LCF: Terminated the $75 million Bilateral LCF.

In connection with these transactions, the requisite lenders under the Credit Agreement also consented to certain amendments, among other things, increasing the Company’s flexibility for restricted payments, investments, and dispositions under the Credit Facilities. As a result of these transactions, the Company derecognized the carrying value of the extinguished TLC and presents the carrying value of the newly issued TLB-2 on the Consolidated Balance Sheet.

In May 2024, TES repriced the TLB-1 and TLC, and the lenders, as part of these debt modifications, agreed to waive mandatory prepayment obligations related to the ERCOT Sale. See Note 20 for additional information on the ERCOT Sale. Additionally, the lenders under the TLB-1, TLC, and RCF consented to certain other covenant improvements.

PEDFA Bonds. In June 2024, TES completed the remarketing of its outstanding $50 million in PEDFA 2009B Bonds and $81 million in PEDFA 2009C Bonds. As part of the remarketing, (i) the PEDFA Bonds were transitioned from a variable daily interest rate to a fixed term rate of 5.25% until June 1, 2027, at which time they are subject to mandatory remarketing during which TES may elect a different interest rate mode; (ii) $133 million of TES LCs that had previously supported the PEDFA Bonds were terminated; (iii) mandatory repurchase and optional redemption provisions were modified; and (iv) certain covenants relating to changes of control, incurrence of liens, and asset sales were amended and became operative. The remarketing transaction is excluded from the Consolidated Statements of Cash Flows as a non-cash item.

Cumulus Digital TLF Repayment. In connection with the AWS Data Campus Sale, the Cumulus Digital TLF was paid in full in March 2024, together with all accrued interest and other outstanding amounts, and related liens, guarantees, and LCs were released and terminated. See Note 20 for additional information on the AWS Data Campus Sale.

Schedule I - Condensed Financial Information of Registrant - Condensed Unconsolidated Balance Sheets (Details) - USD ($)
$ / shares in Units, $ in Millions

Dec. 31, 2024

Dec. 31, 2023

May 17, 2023

May 16, 2023

Assets

Total Assets

$ 6,106

$ 7,121

$ 7,059

$ 7,800

Liabilities and Equity

Total Liabilities

4,719

4,587

4,628

$ 9,800

Stockholders’ Equity

Common stock

^[1]

Additional paid-in capital

1,725

2,346

Accumulated retained earnings (deficit)

(326)

134

Accumulated other comprehensive income (loss)

(12)

(23)

Total Stockholders' Equity

1,387

2,457

2,321

Total Liabilities and Equity

$ 6,106

$ 7,121

$ 7,059

Common stock, par value (in dollars per share)

$ 0.001

Common stock, shares authorized (in shares)

350,000,000

Shares outstanding (in shares)

45,961,910

59,028,843

Shares issued (in shares)

45,961,910

59,028,843

Parent Company

Assets

Investment in TES

$ 1,387

$ 2,457

Total Assets

1,387

2,457

Liabilities and Equity

Total Liabilities

Stockholders’ Equity

Common stock

^[2]

Additional paid-in capital

1,725

2,346

Accumulated retained earnings (deficit)

(326)

134

Accumulated other comprehensive income (loss)

(12)

(23)

Total Stockholders' Equity

1,387

2,457

Total Liabilities and Equity

$ 1,387

$ 2,457

Common stock, par value (in dollars per share)

$ 0.001

Common stock, shares authorized (in shares)

350,000,000

Shares outstanding (in shares)

45,961,910

59,028,843

Shares issued (in shares)

45,961,910

59,028,843

[1]	(a)45,961,910 and 59,028,843 shares issued and outstanding as of December 31, 2024 (Successor) and December 31, 2023 (Successor), respectively.
[2]	Shares issued and outstanding were 45,961,910 and 59,028,843 as of December 31, 2024 (Successor) and December 31, 2023 (Successor), respectively.

Revenue

12 Months Ended

Dec. 31, 2024

Revenue from Contract with Customer [Abstract]

Revenue

6. Revenue

The components of operating revenues for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Capacity revenues	$	192	$	133	$	108	$	377
Electricity sales and ancillary services, ISO/RTO	1,144		880		281		2,534
Physical electricity sales, bilateral contracts, other	147		71		62		298
Other revenue from customers	91		81		27		—
Total revenue from contracts with customers	1,574		1,165		478		3,209
Realized and unrealized gain (loss) on derivative instruments	307		179		732		(120)
Nuclear PTC (a)	220		—		—		—
Other revenue	14		—		—		—
Operating revenues	$	2,115	$	1,344	$	1,210	$	3,089

__________________

(a)During the year ended December 31, 2024 (Successor), $70 million of estimated Nuclear PTCs were utilized as a credit against our federal income tax payable. See Note 7 for additional information on the tax impact of the Nuclear PTC

Accounts Receivable

“Accounts receivable” presented on the Consolidated Balance Sheets were:


	Successor
	December 31, 2024		December 31, 2023
Customer accounts receivable	$	66	$	52
Other accounts receivable	57		85
Accounts receivable	$	123	$	137

During the year ended December 31, 2024 (Successor), the period from May 18 through December 31, 2023 (Successor), and the period from January 1 through May 17, 2023 (Predecessor), there were no significant changes in accounts receivable other than normal receivable recognition and collection transactions. See Note 5 for additional information on Talen’s credit risk on the carrying value of its receivables and for additional information on a Talen Energy Marketing receivables sales arrangement that was terminated in May 2022.

Future Performance Obligations

In the normal course of business, Talen has future performance obligations for capacity sales awarded through market-based capacity auctions and (or) for capacity sales under bilateral contractual arrangements.

The PJM Base Residual Auction for the 2025/2026 PJM Capacity Year was held in July 2024. Talen cleared a total of 6,820 MW at a clearing price of $269.92 per MW-day for the MAAC, PPL, and PSEG locational deliverability areas. The PJM BRAs for any years thereafter have not yet been held, and the PJM BRA for delivery year 2026/2027 has been postponed to July 2025. See Note 12 for additional information on the PJM BRAs.

As of December 31, 2024 (Successor), the expected future period capacity revenues subject to unsatisfied or partially unsatisfied performance obligations were:


	2025		2026 (a)		2027		2028		2029
Expected capacity revenues	$	478	$	281	$	3	$	1	$	—

__________________

(a)Estimated through May 31, 2026. The PJM BRA for the 2026/2027 PJM Capacity Year has been delayed to July 2025.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-10

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-15

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-12

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/606/tableOfContent

+ Details

Nuclear Decommissioning Trust Funds - Summary of Available-for-Sale Debt Securities with Unrealized Losses (Details) $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($)
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Value	$ 357
Unrealized Losses	(7)
Aggregate fair value of debt securities in a loss position for a duration of one year or longer	15
Corporate debt securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Value	71
Unrealized Losses	(2)
Municipal debt securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Value	60
Unrealized Losses	(1)
U.S. Government debt securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Value	226
Unrealized Losses	$ (4)

Supplemental Cash Flow Information - Cash and Restricted Cash (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023	Dec. 31, 2022	Dec. 31, 2021
Restricted Cash and Cash Equivalents Items [Line Items]
Cash and cash equivalents	$ 328	$ 400	$ 169
Restricted cash and cash equivalents:
Restricted cash and cash equivalents	37	501	585
Total	365	901	$ 754	$ 988	$ 743
Restricted Deposits \| TLC
Restricted cash and cash equivalents:
Restricted cash and cash equivalents	0	472
Restricted Deposits \| Nautilus Cryptomine LLC
Restricted cash and cash equivalents:
Restricted cash and cash equivalents	0	10
Restricted Deposits \| Cumulus Digital Holdings LLC
Restricted cash and cash equivalents:
Restricted cash and cash equivalents	0	19
Margin Deposits
Restricted cash and cash equivalents:
Restricted cash and cash equivalents	$ 37	$ 0

Segments (Tables)

12 Months Ended

Dec. 31, 2024

Segment Reporting [Abstract]

Schedule of Consolidated Segment and Reconciliation

Financial results for the segments and reconciliation to consolidated results:


	PJM		Other		Corporate and Eliminations		Total
Year Ended December 31, 2024 (Successor)
Operating revenues	$	1,866	$	367	$	(118)	$	2,115
Operation, maintenance and development expenses (a)	518		74		—		592
Interest expense and other finance charges	—		—		238		238
Other segment items (b)	573
Adjusted EBITDA	775
Capital expenditures	164		24		1		189

May 18 through December 31, 2023 (Successor)
Operating revenues	$	1,120	$	397	$	(173)	$	1,344
Operation, maintenance and development expenses (a)	294		78		(14)		358
Interest expense and other finance charges	—		—		176		176
Other segment items (b)	449
Adjusted EBITDA	377
Capital expenditures	110		45		6		161


January 1 through May 17, 2023 (Predecessor)
Operating revenues	$	1,052	$	195	$	(37)	$	1,210
Operation, maintenance and development expenses (a)	245		47		(7)		285
Interest expense and other finance charges	—		—		163		163
Other segment items (b)	119
Adjusted EBITDA	688
Capital expenditures	132		53		2		187

Year ended December 31, 2022 (Predecessor)
Operating revenues	$	2,902	$	194	$	(7)	$	3,089
Operation, maintenance and development expenses (a)	519		97		(6)		610
Interest expense and other finance charges	—		—		359		359
Other segment items (b)	1,402
Adjusted EBITDA	981
Capital expenditures	237		69		6		312

__________________

(a)This significant segment expense category aligns with the segment-level information that is regularly provided to the CODM.

(b)Other segment items are primarily comprised of fuel and energy purchases.

Reconciliation of segment Adjusted EBITDA to Net Income (Loss):


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Adjusted EBITDA:
PJM	$	775	$	377	$	688	$	981
Total Segment Adjusted EBITDA	$	775	$	377	$	688	$	981
Reconciling Items:
Interest expense and other finance charges	$	(238)	$	(176)	$	(163)	$	(359)
Income tax benefit (expense)	(98)		(51)		(212)		35
Depreciation, amortization and accretion	(298)		(165)		(200)		(520)
Nuclear fuel amortization	(123)		(108)		(33)		(94)
Reorganization (gain) loss, net	—		—		799		(812)
Unrealized (gain) loss on commodity derivative contracts	62		52		(63)		625
Nuclear decommissioning trust funds gain (loss), net	178		108		57		(184)
Stock-based compensation expense	(33)		(19)		—		—
Long-term incentive compensation expense	(21)		(2)		—		—

Gain (loss) on asset sales, net	884		7		50		—
Non-cash impairments	(1)		(3)		(381)		—
Legal settlements and litigation costs	10		84		(1)		(20)
Unusual market events	1		19		(14)		(29)
Net periodic defined benefit cost	(14)		(2)		3		(12)
Operational and other restructuring activities	(76)		(48)		(17)		(570)
Hedge termination losses, net	—		—		—		(158)
Development expenses	(1)		(7)		(10)		(17)
Non-cash inventory net realizable value, obsolescence, and other charges	(20)		(4)		(56)		(3)
Consolidation of subsidiary gain (loss), net	—		—		—		(170)
"Other" operating segment	71		113		37		103
Noncontrolling interest	21		42		14		(3)
Corporate and Eliminations	(76)		(64)		(30)		(69)
Other items	10		(10)		(3)		(17)
Net Income (Loss)	$	1,013	$	143	$	465	$	(1,293)

Income Taxes - Schedule of Inflation Reduction Act Credits (Details)	12 Months Ended
	Dec. 31, 2024 $ / mWh
Income Tax Disclosure [Abstract]
Annual gross receipts, $25 per MWh or less (dollars per MWh)	25
Annual gross receipts, greater than $25 per MWh (dollars per MWh)	25
Credit amount, maximum (dollars per MWh)	15
Credit amount, threshold for annual gross receipts (dollars per MWh)	43.75
Credit amount MWh generated and threshold	0

Basis of Presentation and Summary of Significant Accounting Policies (Details) $ in Millions	1 Months Ended	5 Months Ended	7 Months Ended	12 Months Ended
	May 31, 2022 subsidiary	May 17, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2024 USD ($) $ / mWh Rate	Dec. 31, 2022 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of subsidiaries \| subsidiary	71
Gain (loss) on consolidation of VIE \| $		$ 0	$ 0	$ 0	$ (170)
Nuclear PTC Program, multiplier \| Rate				500.00%
Nuclear PTC Program, maximum (dollars per MWh) \| $ / mWh				15

Risk Management, Derivative Instruments and Hedging Activities

12 Months Ended

Dec. 31, 2024

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Risk Management, Derivative Instruments and Hedging Activities

5. Risk Management, Derivative Instruments and Hedging Activities

Risk Management Objectives

We are exposed to risks arising from our business, including but not limited to market and commodity price risk, credit and liquidity risk, and interest rate risk. The hedging strategies deployed by our commercial organization manage and (or) balance these risks within a structured risk management program in order to minimize near-term future cash flow volatility. Our risk management committee, comprised of certain senior management members across the organization, oversees the management of these risks in accordance with our risk policy. In turn, the risk management committee is overseen by the risk committee of the Board of Directors.

The Board of Directors, including the risk committee, and management have established procedures to monitor, measure, and manage hedging activities and credit risk in accordance with the risk policy.

Key risk control activities, which are designed to ensure compliance with the risk policy, include, among other activities, credit review and approval, validation of transactions and market prices, verification of risk and transaction limits, portfolio stress tests, analysis and monitoring of margin at risk, and daily portfolio reporting.

Market and Commodity Price Risk. Volatility in the wholesale power markets provides uncertainty in the future earnings and cash flows of the business. The price risk Talen is exposed to includes the price variability associated with future sales and (or) purchases of power, natural gas, coal, uranium, oil products, environmental products, and other energy commodities in competitive wholesale markets. Several factors influence price volatility, including: (i) seasonal changes in demand; (ii) weather conditions; (iii) available regional load-serving supply; (iv) regional transportation and (or) transmission availability; (v) market liquidity; and (vi) federal, regional, and state regulations.

Within the parameters of our risk policy, we generally utilize exchange-traded and over-the-counter traded derivative instruments and, in certain instances, structured products, to economically hedge the commodity price risk of the forecasted future sales and purchases of commodities associated with our generation portfolio.

Open commodity purchase (sales) derivatives range in maturity through 2026. The net notional volumes of open commodity derivatives were:


	Successor
	December 31, 2024 (a)	December 31, 2023 (a)
Power (MWh)	(38,615,192)	(27,557,871)
Natural gas (MMBtu)	32,405,460	8,314,060
Emission allowances (tons)	100,000	500,000

__________________

(a)The volumes may be less than the contractual volumes, as the probability that option contracts will be exercised is considered in the volumes displayed.

Interest Rate Risk. Talen is exposed to interest rate risk from the possibility that changes in interest rates will affect future cash flows associated with existing floating rate debt issuances. To reduce interest rate risk, derivative instruments are utilized to economically hedge the interest rates for a predetermined contractual notional amount, which results in a cash settlement between counterparties. To the extent possible, first lien interest rate fixed-for-floating swaps are utilized to hedge this risk.

Open interest rate derivatives are related to the TLB-1 indebtedness and mature in 2026. The net notional volumes of open interest rate derivatives were:


	Successor
	December 31, 2024		December 31, 2023
Interest rate (in millions)	$	290	$	290

Credit Risk. Credit risk, which is the risk of financial loss if a customer, counterparty, or financial institution is unable to perform or pay amounts due, is applicable to cash and cash equivalents, restricted cash and cash equivalents, derivative instruments, and accounts receivable. The maximum amount of credit exposure associated with financial assets is equal to the carrying value of such assets. Credit risk, which cannot be completely eliminated, is managed through a number of practices such as ongoing reviews of counterparty creditworthiness, prepayment, inclusion of termination rights in contracts which are triggered by certain events of default, and executing master netting arrangements that permit amounts between parties to be offset. Additionally, credit enhancements such as cash deposits, LCs, and credit insurance may be employed to mitigate credit risk.

Cash and cash equivalents are placed in depository accounts or high-quality, short-term investments with major international banks and financial institutions. Individual counterparty exposure from over-the-counter derivative instruments is managed within predetermined credit limits and includes the use of master netting arrangements and cash-call margins, when appropriate, to reduce credit risk. Exchange-traded commodity contracts, which are executed through futures commission merchants, have minimal credit risk because they are subject to mandatory margin requirements and are cleared with an exchange. However, Talen is exposed to the credit risk of the futures commission merchants arising from daily variation margin cash calls. Restricted cash and cash equivalents deposited to meet initial margin requirements are held by futures commission merchants in segregated accounts for the benefit of Talen.

Outstanding accounts receivable include those from sales of capacity, generated electricity, and ancillary services through contracts directly with ISOs and RTOs and realized settlements of physical and financial derivative instruments with commodity marketers. Additionally, Talen carries accounts receivable due from joint owners for their portion of operating and capital costs for certain jointly owned facilities that are operated by the Company. The majority of outstanding receivables, which are continually monitored, have customary payment terms. The allowance for doubtful accounts was a non-material amount as of December 31, 2024 (Successor) and December 31, 2023 (Successor).

As of December 31, 2024 (Successor), Talen’s aggregate credit exposure, which excludes the effects of netting arrangements, cash collateral, LCs, and any allowances for doubtful collections, was $350 million and its credit exposure including such net effects was $91 million. Excluding ISO and RTO counterparties, whose accounts receivable settlements are subject to applicable market controls, the ten largest single net credit exposures account for 71% of Talen’s total net credit exposure, which are primarily with entities assigned investment grade credit ratings.

Certain derivative instruments contain credit risk-related contingent features, which may require us to provide cash collateral, LCs, or guarantees from a creditworthy entity if the fair value of a liability eclipses a certain threshold or upon a decline in Talen’s credit rating. The fair values of derivative instruments in a net liability position, and that contain credit risk-related contingent features, were non-material as of December 31, 2024 (Successor) and December 31, 2023 (Successor).

Derivative Instrument Presentation

Balance Sheets Presentation. The fair value of derivative instruments presented within assets and liabilities on the Consolidated Balance Sheets were:


	Successor
	December 31, 2024				December 31, 2023
	Assets		Liabilities		Assets		Liabilities
Commodity contracts	$	65	$	—	$	88	$	32
Interest rate contracts	1		—		1		—

Total current derivative instruments	66		—		89		32
Commodity contracts	4		7		6		5
Interest rate contracts	1		—		—		6
Total non-current derivative instruments	$	5	$	7	$	6	$	11

All commodity and interest rate derivatives are economic hedges where the changes in fair value are presented immediately in income as unrealized gains and losses. Changes in the fair value and realized settlements on commodity derivative instruments are presented as separate components of “Energy and other revenues” and “Fuel and energy purchases” on the Consolidated Statements of Operations. See Note 2 for additional information on derivative instruments and Note 14 for additional information on fair value.

Effect of Netting. Generally, the right of setoff within master netting arrangements permits the fair value of derivative assets to be offset with derivative liabilities. As an election, derivative assets and derivative liabilities are presented on the Consolidated Balance Sheets with the effect of such permitted netting as of December 31, 2024 (Successor) and December 31, 2023 (Successor).

The net amounts of “Derivative instruments” presented as assets and liabilities on the Consolidated Balance Sheets considering the effect of permitted netting and where cash collateral is pledged in accordance with the underlying agreement were:


	Gross Derivative Instruments		Eligible for Offset		Net Derivative Instruments		Collateral (Posted) Received		Net Amounts
December 31, 2024 (Successor)
Assets	$	227	$	(154)	$	73	$	(2)	$	71
Liabilities	173		(154)		19		(12)		7
December 31, 2023 (Successor)
Assets	$	295	$	(198)	$	97	$	(2)	$	95
Liabilities	300		(198)		102		(59)		43

Statements of Operations Presentation. The location and pre-tax effect of “Derivative instruments” presented on the Consolidated Statements of Operations for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Realized gain (loss) on commodity contracts
Energy revenues (a)	$	317	$	360	$	644	$	(613)
Fuel and energy purchases (a)	(35)		(91)		(34)		127
Unrealized gain (loss) on commodity contracts
Operating revenues (b)	42		55		60		677
Energy expenses (b)	20		(3)		(123)		(52)
Realized and unrealized gain (loss) on interest rate contracts
Interest expense and other finance charges	9		(4)		—		30

__________________

(a)Does not include those derivative instruments that settle through physical delivery.

(b)Presented as “Unrealized gain (loss) on derivative instruments” on the Consolidated Statements of Operations.

Contract Terminations

Commodity Hedge Terminations. In March and April 2022, Talen Energy Marketing and a counterparty terminated certain derivative contracts in a net liability position with a carrying value and fair value of $124 million prior to the agreements’ scheduled maturity dates. As the parties agreed to a monthly settlement through January 2023, repayments are presented as “Derivatives with financing elements” on the Consolidated Statements of Cash Flows.

In May 2022, certain commodity counterparties of Talen Energy Marketing terminated derivative contracts in a net liability position with a carrying value and fair value of $33 million prior to the agreements’ scheduled maturity dates. During 2022, Talen Energy Marketing received $7 million in net settlements from counterparties and, at Emergence, settled the remaining $40 million.

Risk Management, Derivative Instruments and Hedging Activities - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2022	May 31, 2022	Apr. 30, 2022
Derivative [Line Items]
Aggregate credit exposure	$ 350
Credit exposure, net	$ 91
Terminated contract, carrying value			$ 33	$ 124
Terminated contract, fair value			$ 33	$ 124
Gain on settlements, net		$ 7
Derivative liability, remaining liability settled		$ 40
Total Net Credit Exposure \| Credit Concentration Risk \| Ten Largest Single Net Credit Exposures Account
Derivative [Line Items]
Concentration risk percentage	71.00%

Long-term Debt and Other Credit Facilities - Schedule of Line of Credit Facilities (Details) - USD ($) $ in Millions	Dec. 31, 2024	May 17, 2023
Debt Instrument [Line Items]
Committed capacity	$ 1,600
LCs Issued		$ 0
Unused Capacity	1,226
Line of Credit \| RCF
Debt Instrument [Line Items]
Committed capacity	700
Unused Capacity	700
Line of Credit \| LCF
Debt Instrument [Line Items]
Committed capacity	900
Unused Capacity	526
Letter of Credit \| LCF
Debt Instrument [Line Items]
LCs Issued	297
Revolving Credit Facility
Debt Instrument [Line Items]
LCs Issued	0
Revolving Credit Facility \| Line of Credit \| RCF
Debt Instrument [Line Items]
LCs Issued	0
Letter of Credit
Debt Instrument [Line Items]
LCs Issued	374
Letter of Credit \| Line of Credit \| RCF
Debt Instrument [Line Items]
LCs Issued	0
Letter of Credit \| Line of Credit \| LCF
Debt Instrument [Line Items]
LCs Issued	$ 374

Earnings Per Share

12 Months Ended

Dec. 31, 2024

Earnings Per Share [Abstract]

Earnings Per Share

17. Earnings Per Share

Basic EPS is computed by dividing net income (loss) by the weighted average number of shares of common stock outstanding during the applicable period. Diluted EPS is computed by dividing income by the weighted-average number of shares of common stock outstanding, increased by incremental shares that would be outstanding if potentially dilutive non-participating securities were converted to common stock as calculated using the treasury stock method. EPS for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Numerator: (Millions of Dollars)
Net Income (Loss)	$	1,013	$	143	$	465	$	(1,293)
Less:
Net income (loss) attributable to noncontrolling interest	15		9		(14)		(4)
Net Income (Loss) Attributable to Stockholders (Successor) / Member (Predecessor)	$	998	$	134	$	479	$	(1,289)

Denominator: (Thousands)
Weighted-Average Number of Common Shares Outstanding - Basic	54,254		59,029		—		—
Warrants	—		84		—		—
Restricted stock units	354		166		—		—
Performance stock units	1,878		120		—		—
Weighted-Average Number of Common Shares Outstanding - Diluted	56,486		59,399		—		—

Earnings per Share - Basic	$	18.40	$	2.27	N/A		N/A
Earnings per Share - Diluted	17.67		2.26		N/A		N/A

For the period from January 1 through May 17, 2023 (Predecessor) and year ended December 31, 2022 (Predecessor), there were no outstanding shares of common stock.

There were no shares excluded from diluted EPS for the year ended December 31, 2024 (Successor). 134,798 PSUs were excluded from diluted EPS for the period from May 18 through December 31, 2023 (Successor) due to their anti-dilutive nature. These awards are excluded from the calculation of EPS because the performance conditions have not been met during the reporting period.

Inventory - Schedule of Inventory (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023
Inventory Disclosure [Abstract]
Coal	$ 92	$ 152
Oil products	65	75
Fuel inventory for electric generation	157	227
Materials and supplies, net	88	72
Environmental products	57	76
Inventory, net	$ 302	$ 375	$ 307

Asset Retirement Obligations and Accrued Environmental Costs - Schedule of Changes in Asset Retirement Obligations (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024
ARO Rollforward
Carrying value, December 31, 2023 (Successor)	$ 751	$ 766	$ 464
Obligations settled	(11)	(11)	(13)
Changes in estimates and (or) settlement dates	3		17
Fair value adjustment at Emergence		(321)
Accretion expense	23	30	55
Obligations incurred			9
Carrying value, December 31, 2024 (Successor)	$ 766	$ 464	$ 498

Risk Management, Derivative Instruments and Hedging Activities - Effect of Netting (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Assets, Gross Derivative Instruments	$ 227	$ 295
Assets, Eligible for Offset	(154)	(198)
Assets, Net Derivative Instruments	73	97
Assets, Collateral (Posted) Received	(2)	(2)
Assets, Net Amounts	71	95
Liabilities, Gross Derivative Instruments	173	300
Liabilities, Eligible for Offset	(154)	(198)
Liabilities, Net Derivative Instruments	19	102
Liabilities, Collateral (Posted) Received	(12)	(59)
Liabilities, Net Amounts	$ 7	$ 43

Stockholders' Equity

12 Months Ended

Dec. 31, 2024

Equity [Abstract]

Stockholders' Equity

18. Stockholders’ Equity

Common Stock Transactions

Share Repurchases and Retirements. Summary of activity under the SRP and direct repurchases:


		Successor
	Year Ended December 31, 2024
		Number of Shares (a) (b)	Share Price (c)		Total Amount
Share repurchases		13,227,222	$	149.50	$	1,977
Share retirements		(13,227,222)	149.50		(1,977)

__________________

(a)Includes 7,307,300 shares repurchased from affiliates of Rubric in July 2024 and December 2024 at a weighted average price of $177.16 per share. Of the total shares repurchased by the Company, $850 million purchased from affiliates of Rubric were not under the SRP.

(b)Includes 5,275,862 shares repurchased as result of a tender offer in June 2024 at a weighted average price of $117.16 per share.

(c)Weighted average price per share, including transaction costs and excise taxes.

As of December 31, 2024 (Successor), all repurchased shares have been retired. See Note 2 for the accounting policy related to treasury stock and retirement of treasury shares.

As of February 27, 2025, TEC had 45,961,910 shares of common stock outstanding.

Exercise of Warrants. In July 2024, a former executive exercised equity-classified warrants to 457,142 shares of the Company’s common stock in a non-cash transaction. After giving effect to the non-cash exercise and related tax withholding, the Company issued 160,289 shares of the Company’s common stock.

Share Repurchases

In May 2024, the Board of Directors approved an increase of the SRP from $300 million to a remaining capacity of $1 billion. In September 2024, the Board of Directors approved an increase of the remaining capacity to $1.25 billion through December 31, 2026. As of December 31, 2024 (Successor), the Company had repurchased approximately 22% of its outstanding shares of common stock for a total of $1.95 billion, exclusive of transaction costs and excise taxes. The Board of Directors approved a portion of the share repurchases executed with Rubric in December 2024 outside of the existing authorization in the SRP. The remaining capacity of the SRP as of December 31, 2024 (Successor) is $1.1 billion.

Employee Stock Purchase Plan

In November 2024, the Board of Directors approved the Company’s 2025 Employee Stock Purchase Plan (“ESPP”), which is subject to approval by shareholders. Effective January 1, 2025, eligible employees can withhold between 1% and 10% of their eligible compensation to purchase TEC common stock at the lesser of 85% of its market value on the offering date or 85% of the market value on the exercise date. Offering dates will occur each January 1 and July 1 and exercise dates each June 30 and December 31. Initially, 500,000 shares may be issued pursuant to the ESPP, with automatic increases in the number of shares authorized for issuance beginning on January 1, 2026 and ending on January 1, 2034. The maximum number of shares that may be issued under the ESPP is 5,000,000 shares.

Acquisition of Noncontrolling Interests

Purchase of Equity in Nautilus. In October 2024, the Company acquired TeraWulf’s 25% equity interest in Nautilus in exchange for $85 million and the distribution by Nautilus of its Bitcoin mining equipment to TeraWulf. As a result of the transaction, the Company owns 100% of the equity of Nautilus. In conjunction with the transaction, we suspended Bitcoin mining operations at the facility.

Purchase of Equity in Cumulus Digital. In March 2024, TES acquired all of the equity of Cumulus Digital held by affiliates of Orion Energy Partners and two former members of Talen senior management in exchange for an aggregate of $39 million. Following these transactions, TES owns 100% of the equity of Cumulus Digital.

Accumulated Other Comprehensive Income

Changes in AOCI for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Beginning balance	$	(23)	$	—	$	(167)	$	(152)
Gains (losses) arising during the period (a)	12		(36)		6		(84)
Reclassifications to Consolidated Statements of Operations (b)	—		7		5		59
Income tax benefit (expense)	(1)		6		(5)		10
Other comprehensive income (loss)	11		(23)		6		(15)
Cancellation of equity at Emergence	—		—		161		—
Accumulated other comprehensive income (loss)	$	(12)	$	(23)	$	—	$	(167)

__________________

(a)Primarily related to “Postretirement benefit actuarial (gain) loss, net” for the period from May 18 through December 31, 2023 (Successor) and “Available-for-sale securities unrealized gain (loss), net” and “Postretirement benefit actuarial (gain) loss, net” for the year ended December 31, 2022 (Predecessor).

(b)Primarily related to “Available-for-sale securities unrealized gain (loss), net” and “Postretirement benefit actuarial (gain) loss, net” for the year ended December 31, 2022 (Predecessor).

The components of AOCI, net of tax, were:


	Successor
	December 31, 2024		December 31, 2023
Available-for-sale securities unrealized gain (loss), net	$	(3)	$	5

Postretirement benefit prior service credits (costs), net	14		—
Postretirement benefit actuarial gain (loss), net	(23)		(28)
Accumulated other comprehensive income (loss)	$	(12)	$	(23)

The locations of pre-tax gains (losses) reclassified from AOCI and included on the Consolidated Statements of Operations for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Nuclear decommissioning trust funds gain (loss), net (a)	$	(1)	$	(7)	$	(4)	$	(33)
Depreciation, amortization and accretion (b)	—		—		1		2
Operation, maintenance and development (c)	1		—		—		(1)
Other non-operating income (expense), net (d)	—		—		(2)		(27)
Total	$	—	$	(7)	$	(5)	$	(59)

__________________

(a)Available-for-sale securities unrealized gain (loss), net.

(b)Qualifying derivatives unrealized gain (loss).

(c)Postretirement benefit prior service credits (costs), net.

(d)Postretirement benefit actuarial gain (loss), net.

The postretirement obligations components of AOCI are not presented in their entirety on the Consolidated Statements of Operations during the periods; rather, they are included in the computation of net periodic defined benefit costs (credits). See Note 15 for additional information.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477968/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478448/946-505-50-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-6

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-13

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-14

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-16

Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 19: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

+ Details

Asset Retirement Obligations and Accrued Environmental Costs (Tables)

12 Months Ended

Dec. 31, 2024

Asset Retirement Obligation Disclosure [Abstract]

Summary of Asset Retirement Obligations and Accrued Environmental Costs


	Successor
	December 31, 2024		December 31, 2023
Asset retirement obligations	$	498	$	464
Accrued environmental costs	21		23
Total asset retirement obligations and accrued environmental costs	519		487
Less: asset retirement obligations and accrued environmental costs due within one year (a)	51		18

Asset retirement obligations and accrued environmental costs due after one year	$	468	$	469

__________________

(a)Presented as “Other current liabilities” on the Consolidated Balance Sheets.

Schedule of Changes in Asset Retirement Obligations

The changes of the ARO carrying value during the periods were:


	ARO Rollforward
Carrying value, December 31, 2022 (Predecessor)	$	751
Obligations settled	(11)
Changes in estimates and (or) settlement dates	3
Accretion expense	23

Carrying value, May 17, 2023 (Predecessor)	$	766


Carrying value, May 18, 2023 (Successor)	$	766
Fair value adjustment at Emergence	(321)
Obligations settled	(11)
Accretion expense	30
Carrying value, December 31, 2023 (Successor)	$	464



Obligations settled	(13)
Changes in estimates and (or) settlement dates	(17)
Accretion expense	55
Obligations incurred	9
Carrying value, December 31, 2024 (Successor)	$	498

Schedule of Asset Retirement Obligations

Supplemental information for the ARO:


	Successor
	December 31, 2024		December 31, 2023
Supplemental Information
Nuclear (a)	$	242	$	214
Non-Nuclear (b)	256		250
Carrying value	$	498	$	464

__________________

(a)Obligations are expected to be settled with available funds in the NDT at the time of decommissioning. See Note 14 for additional information on the NDT.

(b)Certain obligations are: (i) partially supported by surety bonds, some of which have been collateralized with cash and (or) LCs; or (ii) partially prefunded under phased installment agreements.

Property, Plant, and Equipment (Tables)

12 Months Ended

Dec. 31, 2024

Property, Plant and Equipment [Abstract]

Summary of Depreciation, Amortization, and Accretion Expense


		Successor
		December 31, 2024						December 31, 2023
	Estimated Useful Life (years)	Gross Value		Accumulated Depreciation		Carrying Value		Gross Value		Accumulated Depreciation		Carrying Value
Electric generation	3-27	$	3,030	$	(292)	$	2,738	$	3,178	$	(109)	$	3,069
Nuclear fuel	1-6	322		(152)		170		228		(55)		173
Other property and equipment	1-26	90		(18)		72		358		(21)		337

Capitalized software	1-5	8		(3)		5		6		(1)		5
Construction work in progress		169		—		169		255		—		255
Property, plant and equipment, net		$	3,619	$	(465)	$	3,154	$	4,025	$	(186)	$	3,839

The components of “Depreciation, amortization and accretion” presented on the Consolidated Statements of Operations for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Depreciation expense (a)	$	225	$	133	$	173	$	432
Amortization expense (b)	16		1		4		12
Accretion expense (c)	57		31		24		78
Other	—		—		(1)		(2)
Depreciation, amortization and accretion	$	298	$	165	$	200	$	520

__________________

(a)Electric generation and other property and equipment.

(b)Intangible assets and capitalized software.

(c)ARO and accrued environmental cost accretion. See Note 11 for additional information.

The proportionate share of “Property, plant and equipment, net” related to Susquehanna presented on the Consolidated Balance Sheets was:


	Successor
	December 31, 2024		December 31, 2023
Ownership interest	90%		90%

Electric generation	$	2,206	$	2,187
Nuclear fuel	322		228
Other property and equipment	25		19
Capitalized software	2		2

Construction work in progress	109		95
Proportionate property, plant and equipment, cost	2,664		2,531
Less: accumulated depreciation and amortization	326		121
Proportionate property, plant and equipment, net	$	2,338	$	2,410

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense

Estimated intangible assets amortization expense for the next four years is:


	2025		2026		2027		2028 (a)
Estimated amortization expense	$	14	$	5	$	3	$	1

__________________

(a)Supply contracts underlying the nuclear fuel intangible assets expire in 2028.

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2024
Audit Information [Abstract]
Auditor Name	PricewaterhouseCoopers LLP
Auditor Location	Houston, Texas
Auditor Firm ID	238

Fresh Start Accounting - Narrative (Details) - USD ($) $ in Millions		5 Months Ended	12 Months Ended
	May 17, 2023	May 17, 2023	Dec. 31, 2024	Dec. 31, 2023	May 16, 2023
Reorganization, Chapter 11 [Line Items]
Voting shares of successor, percentage	50.00%	50.00%
Total Assets	$ 7,059	$ 7,059	$ 6,106	$ 7,121	$ 7,800
Total Liabilities	4,628	4,628	$ 4,719	$ 4,587	$ 9,800
Enterprise value	$ 4,500	$ 4,500
Nuclear fuel discount rate			8.50%
Shares outstanding (in shares)	59,028,843	59,028,843	45,961,910	59,028,843
Equity-classified warrants	$ 8	$ 8
Cash paid for reorganization expenses		$ 308
Minimum
Reorganization, Chapter 11 [Line Items]
Weighted average cost of capital, discount rate	8.50%	8.50%
Maximum
Reorganization, Chapter 11 [Line Items]
Weighted average cost of capital, discount rate	46.50%	46.50%
Reorganization Adjustments
Reorganization, Chapter 11 [Line Items]
Total Assets	$ (722)	$ (722)
Total Liabilities	(4,138)	$ (4,138)
Payment of professional fees	$ 52

Property, Plant, and Equipment - Proportionate Shares of Property, Plant and Equipment, Net (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023
Property, Plant and Equipment [Line Items]
Gross Value	$ 3,619	$ 4,025
Accumulated Depreciation	(465)	(186)
Carrying Value	$ 3,154	$ 3,839	$ 3,864
Susquehanna
Property, Plant and Equipment [Line Items]
Ownership interest	90.00%	90.00%
Gross Value	$ 2,664	$ 2,531
Accumulated Depreciation	(326)	(121)
Carrying Value	2,338	2,410
Electric generation
Property, Plant and Equipment [Line Items]
Gross Value	3,030	3,178
Accumulated Depreciation	(292)	(109)
Carrying Value	2,738	3,069
Electric generation \| Susquehanna
Property, Plant and Equipment [Line Items]
Gross Value	2,206	2,187
Nuclear fuel
Property, Plant and Equipment [Line Items]
Gross Value	322	228
Accumulated Depreciation	(152)	(55)
Carrying Value	170	173
Nuclear fuel \| Susquehanna
Property, Plant and Equipment [Line Items]
Gross Value	322	228
Other property and equipment
Property, Plant and Equipment [Line Items]
Gross Value	90	358
Accumulated Depreciation	(18)	(21)
Carrying Value	72	337
Other property and equipment \| Susquehanna
Property, Plant and Equipment [Line Items]
Gross Value	25	19
Capitalized software
Property, Plant and Equipment [Line Items]
Gross Value	8	6
Accumulated Depreciation	(3)	(1)
Carrying Value	5	5
Capitalized software \| Susquehanna
Property, Plant and Equipment [Line Items]
Gross Value	2	2
Construction work in progress
Property, Plant and Equipment [Line Items]
Gross Value	169	255
Carrying Value	169	255
Construction work in progress \| Susquehanna
Property, Plant and Equipment [Line Items]
Gross Value	$ 109	$ 95

Long-term Debt and Other Credit Facilities - Schedule of Maturities of Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Debt Disclosure [Abstract]
2025	$ 17
2026	17
2027	17
2028	17
2029	17
Thereafter	2,952
Total principal	$ 3,038	$ 2,849

Fair Value - Summary of Carrying Value and Fair Value of Indebtedness (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023
Carrying Value
Reclassification of previously capitalized debt issuance costs to Long-term debt	$ 3,004	$ 2,820
Other short-term indebtedness	0	6
Fair Value
Long-term debt	3,120	2,934	$ 2,845
Other short-term indebtedness	$ 0	$ 6

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

Income Taxes - Schedule of Components of Income Tax (Expense) Benefit (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Current:
Federal	$ (15)	$ 3	$ (113)	$ (9)
State	(2)	1	(31)	(4)
Current income taxes	(17)	4	(144)	(13)
Deferred:
Federal	(184)	(55)	47	68
State	(11)	0	(1)	(21)
Deferred income taxes	(195)	(55)	46	48
Deferred income taxes				47
Investment tax credit	0	0	0	1
Income tax benefit (expense)	$ (212)	$ (51)	$ (98)	$ 35

Supplemental Cash Flow Information

12 Months Ended

Dec. 31, 2024

Supplemental Cash Flow Elements [Abstract]

Supplemental Cash Flow Information

19. Supplemental Cash Flow Information

Supplemental information for the Consolidated Statements of Cash Flows for the periods was:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Cash paid during the period
Interest and other finance charges, net of capitalized interest (a)	$	255	$	133	$	283	$	277
Income taxes, net	20		12		7		14

Unrealized (gain) loss on derivative instruments included on the Statements of Cash Flows
Commodity contracts	$	(62)	$	(52)	$	63	$	(625)
Interest rate swap contracts (interest expense)	(7)		12		2		(23)
Unrealized (gain) loss on derivative instruments	$	(69)	$	(40)	$	65	$	(648)

Depreciation, amortization and accretion included on the Statements of Cash Flows
Depreciation, amortization and accretion	$	298	$	165	$	200	$	520

Other	(13)		(8)		8		29
Depreciation, amortization and accretion	$	285	$	157	$	208	$	549

Reconciliation of other non-cash operating activities

Bitcoin revenue	$	(91)	$	(81)	$	(27)	$	—
Stock-based compensation	33		19		—		—
Fair value adjustment on distribution of miners	14		—		—		—
Derivative option premium amortization	11		52		29		67
Derivatives with financing elements	—		—		—		104
Non-cash environmental liability revisions	—		—		—		13






Other	7		17		5		16
Total	$	(26)	$	7	$	7	$	200

Non-cash investing activities
Capital expenditure accrual increase (decrease)	$	6	$	7	$	(28)	2
Accounts receivable contributed to equity method investment	—		—		—		2

Non-cash financing activities
Non-cash increase to PP&E and decrease to other current assets for contribution of Bitcoin miners to Nautilus (b)	$	—	$	—	$	14	$	30
Non-cash decrease to PP&E and decrease to noncontrolling interest for distribution of Bitcoin miners to TeraWulf (c)	43		—		3		—
Non-cash increase to PP&E and increase to noncontrolling interest for contribution of Bitcoin miners by TeraWulf (b)	—		—		38		14

__________________

(b)In 2023, each of the joint venture partners of Nautilus made non-cash contributions to Nautilus of Bitcoin miners that increased PP&E.

(c)In 2024, Nautilus distributed Bitcoin miners to TeraWulf as part of the buyout of TeraWulf’s noncontrolling interest.

Cash and Restricted Cash


	Successor
	December 31, 2024		December 31, 2023
Cash and cash equivalents	$	328	$	400

Restricted cash and cash equivalents:
TES TLC debt restricted deposits	—		472
Nautilus project restricted deposits	—		10
Commodity exchange margin deposits	37		—
Cumulus Digital restricted deposits	—		19
Restricted cash and cash equivalents	37		501
Total	$	365	$	901

Income Taxes

12 Months Ended

Dec. 31, 2024

Income Tax Disclosure [Abstract]

Income Taxes

7. Income Taxes

The components of “Income tax benefit (expense)” for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Federal	$	(113)	$	3	$	(15)	$	(9)
State	(31)		1		(2)		(4)
Current income taxes	(144)		4		(17)		(13)
Federal	47		(55)		(184)		68
State	(1)		—		(11)		(21)
Deferred income taxes	46		(55)		(195)		47
Investment tax credit	—		—		—		1
Income tax benefit (expense)	$	(98)	$	(51)	$	(212)	$	35

Effective Tax Rate Reconciliations

The reconciliations of the effective tax rate for the periods were:


	Successor						Predecessor
	Year Ended December 31, 2024			May 18 through December 31, 2023			January 1 through May 17, 2023			Year Ended December 31, 2022

Income (loss) before income taxes	$	1,111		$	194		$	677		$	(1,328)
Income tax benefit (expense)	(98)			(51)			(212)			35
Effective tax rate	8.8		%	26.3		%	31.3		%	2.6		%
Federal income tax statutory tax rate	21		%	21		%	21		%	21		%
Income tax benefit (expense) computed at the federal income tax statutory tax rate	$	(234)		$	(41)		$	(143)		$	279
Income tax increase (decrease) due to:
Change in valuation allowance	128			(43)			129			(198)
Nuclear PTC	46			—			—			—
Reorganization adjustments	23			26			(138)			—
Return to provision	11			—			—			—
Other permanent differences	3			22			(16)			(94)
Nuclear decommissioning trust taxes	(27)			(16)			(9)			28

State income taxes, net of federal benefit	(48)			1			(34)			19

Other	—			—			(1)			1
Income tax benefit (expense)	$	(98)		$	(51)		$	(212)		$	35

Deferred Taxes

The components of deferred tax liabilities and deferred tax assets were:


	Successor
	December 31, 2024		December 31, 2023

Nuclear decommissioning trust	$	502	$	443
Property, plant and equipment, net	465		560
Unrealized gain on qualifying derivatives	32		12
Investment in subsidiaries	—		14

Deferred tax liabilities	999		1,029
Less:
Interest limitation carryforward	340		336
Federal net operating loss carryforwards	164		273
Accrued pension costs	80		78
Accrued liabilities	30		26
State net operating loss carryforwards	15		26


Other	8		10
Deferred tax assets	637		749
Valuation allowance	—		(128)
Deferred tax liabilities, net	$	362	$	408

Net Operating Losses

The components of NOL carryforwards were:


	Successor
	December 31, 2024		December 31, 2023
Federal, expirations 2036 - 2037	$	—	$	43
Federal, indefinite expiration, limited to annual utilization of 80%	783		1,258
State, expirations 2025 - 2043	310		555

See “Emergence from Restructuring” below for information on limitations on our NOLs.

Unrecognized Tax Benefits

Unrecognized tax benefits as of December 31, 2024 (Successor) and December 31, 2023 (Successor) were a non-material amount and it is not expected the total amount of unrecognized tax benefit will change significantly within one year.

All tax returns filed for years December 31, 2021 and forward are open to examination by the relevant taxing authorities.

Emergence from Restructuring

The Company evaluated, including the change in control resulting from its Emergence from bankruptcy, the tax impact of its Restructuring as described in Note 3. As part of the Restructuring, a substantial portion of the Company’s prepetition debt was extinguished, resulting in cancellation of debt income (“CODI”). A taxpayer emerging from bankruptcy may exclude CODI from taxable income but must first reduce its tax attributes by the amount of CODI realized. The Company realized CODI of $1.2 billion, which resulted in a partial reduction in tax basis in PP&E assets.

Upon Emergence, the Company experienced an ownership change under Section 382 of the Internal Revenue Code. The Internal Revenue Code Sections 382 and 383 impose limitations on the ability of a company to utilize tax attributes after experiencing an ownership change. States generally have similar tax attribute limitation rules following an ownership change. The Company also applied fresh start accounting. As a result, deferred tax assets and liabilities were adjusted based on the Successor GAAP financial statements. See Note 4 for additional information on fresh start accounting.

Valuation Allowance

The Company’s most significant deferred tax assets are its net operating losses and interest limitation carryforward. Management assesses the available positive and negative evidence to estimate whether it is more likely than not that sufficient future taxable income will be generated to permit the use of existing deferred tax assets. Such assessment includes the evaluation of historical earnings after adjusting for certain nonrecurring items for the purpose of projecting future taxable income. Negative evidence in the form of cumulative losses are no longer present as the Company has returned to profitability. The existence of objective positive evidence allows for consideration of other subjective evidence, including (but not limited to) Talen’s projections for future income which would allow for utilization of all net operating losses and interest limitation carryforwards. At each period, management will continue to assess the available positive and negative evidence to determine the need for a valuation allowance.

As a result of the assessment, it was determined that it is more likely than not that federal and state deferred tax assets will be fully utilized by future taxable income. As of December 31, 2024 (Successor), the entire federal and state valuation allowances were released, resulting in a $128 million tax benefit.

For the period from May 18 through December 31, 2023 (Successor), a $43 million tax expense was recognized for the increase in federal and state valuation allowances based on the realizability of deferred tax assets. For the period from January 1 through May 17, 2023 (Predecessor), a $129 million benefit was recognized for the reduction in federal and state valuation allowances. The change in valuation allowance estimates was the result of tax attribute reduction from the cancellation of debt income that was realized upon Emergence. For the year ended December 31, 2022 (Predecessor) a $198 million tax expense was recognized for the increase in federal and state valuation allowances based on realizability of deferred tax assets.

Inflation Reduction Act of 2022

The Inflation Reduction Act was signed into law in August 2022. Among the Act’s provisions are amendments to the Internal Revenue Code to create a nuclear production tax credit program.

The Nuclear PTC program provides qualified nuclear power generation facilities with a $3 per MWh transferable credit for electricity produced and sold to an unrelated party during each tax year. Electricity produced and sold by Susquehanna to third parties after December 31, 2023 through December 31, 2032 qualifies for the credit, which is subject to potential adjustments. Such adjustments include inflation escalators, a five-times increase in tax credit value (to $15 per MWh) if the qualifying generation facility meets prevailing wage requirements (which we expect to meet), and a pro-rata decrease in tax credit value once the annual gross receipts of a qualifying generation facility exceeds $25 per MWh. As the credit is eliminated when the annual gross receipts are equivalent to $43.75 per MWh (adjusted for inflation), the Nuclear PTC program is expected to create a minimum price Susquehanna is expected to receive for its generation. Susquehanna generated 17 million MWh sold to third parties in calendar year 2024.

The credit would be:


Annual Gross Receipts						Credit Amount
$25 per MWh or less						$15 per MWh
Greater than $25 per MWh						Ratably reduced until gross receipts equal $43.75 per MWh, $0 after that threshold

The Inflation Reduction Act’s provisions are subject to implementation regulations, the terms of which are not yet fully known. No assurance can be provided as to the magnitude of the benefit to Susquehanna, as the Inflation Reduction Act’s provisions, including the computations of the Nuclear PTC, are subject to implementation regulations that could impact the credit value recognized to date and credit value available in future periods. Accordingly, Talen cannot fully predict the realization of any minimum price for Susquehanna’s generation and (or) impacts to Talen’s liquidity or results of operations. See Note 6 for additional information on Nuclear PTC revenue recognized.

Current Taxes Payable

Current tax liabilities presented as “Other current liabilities” on the Consolidated Balance Sheets were $53 million as of December 31, 2024 (Successor) and $2 million as of December 31, 2023 (Successor).

- Definition

The entire disclosure for income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 231
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-231

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12C

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12B

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477891/740-270-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479360/740-10-S99-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-13

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
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-Subparagraph (b)
-Publisher FASB
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482603/740-30-50-2

+ Details

Property, Plant, and Equipment - Estimated Amortization Expense (Details) - Nuclear fuel $ in Millions	Dec. 31, 2024 USD ($)
Property, Plant and Equipment [Line Items]
2025	$ 14
2026	5
2027	3
2028	$ 1

Nuclear Decommissioning Trust Funds - Summary of Maturities for Available-for-sale Debt Securities (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Maturities within one year	$ 82	$ 105
Maturities within two to five years	220	194
Maturities thereafter	309	280
Debt securities, fair value	$ 611	$ 579

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 103
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-103

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-Topic 820
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 320
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-Paragraph 1
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-Topic 942
-SubTopic 210
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-Paragraph 1
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Emergence from Restructuring

12 Months Ended

Dec. 31, 2024

Plan of Reorganization [Abstract]

Emergence from Restructuring

3. Emergence from Restructuring

Voluntary Reorganization Under Chapter 11 of the U.S. Bankruptcy Code

Restructuring Transactions and Emergence

The Restructuring transactions were completed, and the Company emerged from the Restructuring, on May 17, 2023. Pursuant to the Plan of Reorganization, among other things:

•Claims against TEC were paid in full in cash or reinstated. All existing equity interests in TEC were extinguished, and new equity interests in TEC were issued as follows:

•The existing intercompany ownership structure of the debtors remained in place and intercompany claims were extinguished.

4. Fresh Start Accounting

Reorganization Value


	May 17, 2023
Enterprise value (a)	$	4,500
Plus: Cash and cash equivalents and Restricted cash and cash equivalents (b)	701
Plus: Current liabilities excluding long-term debt due within one year	514
Plus: Non-current liabilities excluding long-term debt and liability-classified warrants	1,234
Plus: Fair value of noncontrolling interest	110
Reorganization value to be allocated	$	7,059

__________________

(a)Excludes any value associated with noncontrolling interest.

(b)Excludes $52 million for payment of professional fees.

The following table reconciles TES’s enterprise value to the estimated fair value at Emergence:


	May 17, 2023
Enterprise value (a)	$	4,500
Plus: Cash and cash equivalents and Restricted cash and cash equivalents (b)	701
Less: Fair value of debt	(2,845)
Less: Liability-classified warrants	(35)
Fair value of member’s equity (c)	2,321
Plus: Fair value of noncontrolling interest	110
Fair value of equity	$	2,431

__________________

(a)Excludes any value associated with noncontrolling interest.

(b)Excludes $52 million for payment of professional fees.

(c)Issued in accordance with the Plan of Reorganization. Includes 59,028,843 shares of TEC common stock and $8 million of equity-classified warrants.

Consolidated Balance Sheet


	May 17, 2023
Assets	Predecessor		Reorganization Adjustments (a)			Fresh Start Adjustments			Successor
Cash and cash equivalents	$	1,302	$	(1,133)	(b)	$	—		$	169
Restricted cash and cash equivalents	240		426		(c)	(81)		(q)	585
Accounts receivable, net	148		(3)		(d)	—			145
Inventory, net	448		—			(141)		(r)	307
Derivative instruments	818		—			(632)		(q)	186
Other current assets	135		—			(5)		(s)	130
Total current assets	3,091		(710)			(859)			1,522
Property, plant and equipment, net	4,322		—			(458)		(t)	3,864
Nuclear decommissioning trust funds	1,465		—			—			1,465
Derivative instruments	37		—			(37)		(q)	—
Other noncurrent assets	146		(12)		(e)	74		(u)	208
Total Assets	$	9,061	$	(722)		$	(1,280)		$	7,059

Liabilities and Equity
Revolving credit facilities	$	848	$	(848)	(f)	$	—		$	—
Long-term debt, due within one year	1,005		(1,000)		(g)	—			5
Accrued interest	288		(284)		(h)	—			4
Accounts payable and other accrued liabilities	382		3		(i)	—			385
Derivative instruments	711		—			(654)		(q)	57
Other current liabilities	414		(349)		(j)	3		(v)	68
Total current liabilities	3,648		(2,478)			(651)			519
Long-term debt	2,504		281		(k)	55		(w)	2,840
Liabilities subject to compromise	2,788		(2,788)		(l)	—			—
Derivative instruments	135		—			(93)		(q)	42
Postretirement benefit obligations	(1)		302		(m)	34		(x)	335
Asset retirement obligations and accrued environmental costs	580		202		(m)	(340)		(y)	442
Deferred income taxes	82		283		(n)	(8)		(z)	357
Other noncurrent liabilities	19		60		(o)	14		(aa)	93
Total Liabilities	9,755		(4,138)			(989)			4,628
Member’s equity	(818)		3,416		(p)	(277)		(bb)	2,321
Noncontrolling interests	124		—			(14)		(cc)	110
Total Equity	(694)		3,416			(291)			2,431
Total Liabilities and Equity	$	9,061	$	(722)		$	(1,280)		$	7,059

Reorganization Adjustments

The reorganization adjustments required in connection with the application of fresh start accounting and the allocation of the enterprise value were:

(b)The uses of “Cash and cash equivalents” at Emergence resulting from the implementation of the Plan of Reorganization were:


Proceeds from rights offering	$	1,400
Proceeds from TLB-1 and TLC	1,019
Proceeds from Secured Notes	1,200
Release of restricted cash	89
Payment of claims under prepetition senior secured revolving credit facility	(1,029)
Payment of claims under other prepetition secured indebtedness	(2,136)
Payment of debtor-in-possession term loan	(1,012)
Restriction of cash relating to TLC LCF	(470)
Payment of debt issuance costs on exit financing (TLB-1, TLC, and Secured Notes)	(54)
Funding of professional fees escrow account	(52)
Payment of hedge rejections	(42)
Payment to general unsecured creditors trust	(26)
Payment of professional fees	(22)
Other (a)	2
Total uses of Cash and cash equivalents	$	(1,133)

__________________

(a)Includes $1 million of proceeds from Riverstone for payment to general unsecured creditors trust.

(c)“Restricted cash and cash equivalents” net change:


Restriction of cash relating to TLC LCF	$	470
Funding of professional fees escrow account	52
Release of restricted cash	(89)
Payment of professional fees	(7)
Net change in Restricted cash and cash equivalents	$	426

(d)“Accounts receivable, net” net change related to settlement of affiliate receivables.

(e)“Other noncurrent assets” net change:


Write-off of debt issuance costs associated with prepetition senior secured revolving credit facility	$	(22)
Reclassification of previously capitalized debt issuance costs to Long-term debt	(14)
Capitalization of debt issuance costs	24
Net change in Other noncurrent assets	$	(12)

(f)Payment of principal amounts owed under prepetition senior secured revolving credit facility.

(g)Repayment of debtor-in-possession credit facilities.

(h)“Accrued interest” net change:


Payment of accrued interest on prepetition senior secured revolving credit facility	$	(183)
Payment of accrued interest on other prepetition secured indebtedness	(89)
Payment of accrued interest on debtor-in-possession credit facilities	(12)
Net change in Accrued interest	$	(284)

(i)“Accounts payable and other accrued liabilities” net change:


Payment of hedge contract rejections	$	(42)
Payment of professional fees	(6)
Reinstatement of liabilities subject to compromise	38
Accrual for professional fees incurred at Emergence	13
Net change in Accounts payable and other accrued liabilities	$	3

(j)“Other current liabilities” net change:


Issuance of equity for backstop premium	$	(380)
Reinstatement of liabilities subject to compromise	31
Net change in Other current liabilities	$	(349)

(k)“Long-term debt” net change:


Payment of claims under prepetition secured indebtedness	$	(2,048)
Borrowings of $1.2 billion under the Secured Notes (a)	1,179
Borrowings of $580 million under TLB-1 (b)	548
Borrowings of $470 million under TLC (c)	446
Reinstatement of PEDFA 2009B Bonds and PEDFA 2009C Bonds (d)	130
Write-off of prepetition secured indebtedness issuance costs	26
Net change in Long-term debt	$	281

______________

(a)Net of an aggregate initial purchaser discount and debt issuance costs of $21 million.

(b)Net of an aggregate original issue discount and debt issuance costs of $32 million.

(c)Net of an aggregate original issue discount and debt issuance costs of $24 million.

(d)Includes recognition of $4 million of interest expense.

(l)“Liabilities subject to compromise” settled or reinstated at Emergence in accordance with the Plan of Reorganization:


Liabilities subject to compromise prior to Emergence
Debt	$	1,555
Termination of retail contracts	447
Postretirement benefit obligations	305
Asset retirement obligations and accrued environmental costs	220
Other liabilities	92
Deferred tax liabilities	77
Accounts payable and accrued liabilities	51
Accrued interest	41
Total	2,788

Reinstatement and settlements of certain Liabilities subject to compromise
Reinstatement of liabilities subject to compromise (a)	(801)
Excess fair value ascribed to lenders participating in rights offering	(315)
Issuance of member’s equity to holders of claims under prepetition unsecured notes and PEDFA 2009A Bonds	(186)
Payment to general unsecured creditors trust	(24)
Total	(1,326)
Gain on derecognition of certain Liabilities subject to compromise (b)	$	1,462

______________

(a)Primarily includes postretirement benefit obligations, AROs, and deferred income taxes.

(b)Represents liabilities subject to compromise that were discharged in accordance with the Plan of Reorganization.

(m)Reinstatement of “Liabilities subject to compromise.”

(n)“Deferred income taxes” net change:


Increase in deferred tax liabilities primarily due to estimated tax attribute reduction from the recognition of cancellation of debt income, partially offset by change in valuation allowance	$	206
Reinstatement of liabilities subject to compromise	77
Net change in Deferred income taxes	$	283

(o)“Other noncurrent liabilities” net change:


Issuance of liability-classified warrants	$	35
Reinstatement of liabilities subject to compromise	25
Net change in Other noncurrent liabilities	$	60

The estimated fair value of liability-classified warrants was determined using a Black-Scholes Option Pricing Model with the following assumptions at Emergence:


Expected volatility	30		%
Expected term (years)	5
Expected dividend yield	—		%
Risk-free interest rate	3.6		%
Strike price per share	$	52.92
Fair value per share	$	11.29

(p)“Member’s equity” net change:


Gain on settlement of liabilities subject to compromise	$	1,462
Other losses attributable to gain on debt discharge	(3)
Gain on debt discharge	1,459
Write-off of deferred financing cost	(46)
Professional fees expensed at Emergence	(27)
Restructuring-related compensation expense	(8)
Total reorganization items from reorganization adjustments	1,378
Interest expense incurred at Emergence	(4)
Income from reorganization adjustments before income taxes	1,374
Income tax expense	(206)
Net income from reorganization adjustments	1,168
Issuance of member’s equity in connection with rights offering	1,715
Issuance of member’s equity for backstop premium	380
Issuance of member’s equity to holders of claims under prepetition unsecured notes and PEDFA 2009A Bonds	186
Issuance of equity-classified warrants	8
Issuance of liability-classified warrants	(35)
Other (a)	(6)
Net change in Member’s equity	$	3,416

______________

(a)Includes $1 million of proceeds from Riverstone for payment to general unsecured creditors trust.

Fresh Start Adjustments

(q)Net presentation of derivatives on the Consolidated Balance Sheets. See Note 2 for additional information on the related accounting policy.

(r)“Inventory, net” fair value adjustments:


Coal	$	(33)
Oil products	11
Materials and supplies	(133)
Environmental products	14
Total adjustment to Inventory, net	$	(141)

(s)“Other current assets” primarily represents miscellaneous fair value adjustments.

(t)“Property, plant and equipment, net” fair value adjustments:


Electric generation	$	(350)
Other property and equipment	(80)
Intangible assets	(65)
Capitalized software	(3)
Construction work in progress	40
Total adjustment to Property, plant and equipment, net	$	(458)

(u)“Other noncurrent assets” fair value adjustments:


Favorable supply contracts (a)	$	109
Fair value adjustment to equity method investments	3
Eliminate debt issuance costs associated with debtor-in-possession credit facilities	(29)
Fair value reduction to other miscellaneous assets	(9)
Total adjustment to Other noncurrent assets	$	74

__________________

(a)The fair value of supply contracts was determined utilizing the present value of the after-tax difference between the pricing of actual contracts in place and a current market benchmark.

(v)“Other current liabilities” fair value adjustments, primarily related to short-term AROs.

(w)“Long-term debt” fair value adjustments:


Eliminate debt issuance costs associated with prepetition secured notes, prepetition TLB and LMBE-MC TLB	$	48
Fair value adjustment to Cumulus Digital TLF	11
Fair value adjustment to LMBE-MC TLB	(4)
Total adjustment to Long-term debt	$	55

Fair value adjustments to “Long-term debt” were determined using a lattice model, given that the debt can be prepaid by the borrower prior to the maturity date.

(x)Change in accounting policy for discount rates used to estimate postretirement obligations from a bond-matching model to yield curve approach. See Note 2 for additional information.

(z)Adjustment to “Deferred income taxes” for the change in financial reporting basis of assets and liabilities as a result of the adoption of fresh start accounting.

(bb)Cumulative impact of fresh start accounting adjustments presented herein.

(cc)“Noncontrolling interests” fair value adjustments for certain subsidiaries.

Liabilities Subject to Compromise


	Predecessor
	December 31, 2022
Debt (a)	$	1,558
Termination of retail power and other contracts	447
Postretirement benefit obligations (a)	309
Asset retirement obligations and accrued environmental costs (a)	219
Other liabilities (a)	114
Deferred tax liabilities	83
Accounts payable and accrued liabilities	53
Accrued interest	41
Derivatives (a)	1
Liabilities Subject to Compromise	$	2,825

__________________

(a)Includes both current and noncurrent amounts.

Reorganization Income (Expense), net

“Reorganization income (expense), net” for the relevant periods were:


	Predecessor
	January 1 through May 17, 2023		Year Ended December 31, 2022
Backstop premium	$	(70)	$	(310)
Gain (loss) on debt discharge	1,459		—
Gain (loss) on revaluation adjustments	(460)		—
Professional fees	(56)		(210)
Make-whole premiums and accrued interest on certain indebtedness	(21)		(183)
Professional fees incurred to obtain the debtor-in-possession credit facilities	—		(70)
Write-off of deferred financing cost and original issue discount	(46)		(30)
Other	(7)		(9)
Reorganization Income (Expense), net	$	799	$	(812)

Postretirement Benefit Obligations - Schedule of Funded Status (Details) $ in Millions	Dec. 31, 2024 USD ($)
Benefit Plan for UMWA Represented Retirees of Pennsylvania Mines, LLC
Defined Benefit Plan Disclosure [Line Items]
Trust Asset Fair Value	$ 21
Obligation Fair Value	16
Overfunded Status	5
Coal Worker's Pneumoconiosis (Black Lung) Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Trust Asset Fair Value	9
Obligation Fair Value	5
Overfunded Status	$ 4

- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References + Details

Fair Value

12 Months Ended

Dec. 31, 2024

Fair Value Disclosures [Abstract]

Fair Value

14. Fair Value

Recurring Fair Value Measurements

Financial assets and liabilities reported at fair value on a recurring basis primarily include energy commodity derivatives, interest rate derivatives, and investments held within the NDT.

The classifications of recurring fair value measurements within the fair value hierarchy were:


	Successor
	December 31, 2024								December 31, 2023
	Level 1		Level 2		NAV		Netting (a)		Total		Level 1		Level 2		NAV		Netting (a)		Total
Assets
Cash equivalents	$	—	$	—	$	3	$	—	$	3	$	—	$	—	$	9	$	—	$	9
Equity securities (b)	758		—		347		—		1,105		629		—		384		—		1,013
U.S. Government debt securities	353		—		—		—		353		337		—		—		—		337
Municipal debt securities	—		85		—		—		85		—		86		—		—		86
Corporate debt securities	—		173		—		—		173		—		156		—		—		156

Receivables (payables), net (c)	—		—		—		—		5		—		—		—		—		(26)
NDT funds	1,111		258		350		—		1,724		966		242		393		—		1,575

Commodity derivatives	134		91		—		(156)		69		98		196		—		(200)		94
Interest rate derivatives	—		2		—		—		2		—		1		—		—		1
Total assets	$	1,245	$	351	$	350	$	(156)	$	1,795	$	1,064	$	439	$	393	$	(200)	$	1,670

Liabilities
Commodity derivatives	$	145	$	29	$	—	$	(167)	$	7	$	155	$	139	$	—	$	(257)	$	37
Interest rate derivatives	—		—		—		—		—		—		6		—		—		6

Total liabilities	$	145	$	29	$	—	$	(167)	$	7	$	155	$	145	$	—	$	(257)	$	43

__________________

(a)Amounts represent netting pursuant to master netting arrangements and cash collateral held or placed with the same counterparty.

(b)Includes commingled equity and fixed income funds and real estate investment trusts.

(c)Represents: (i) interest and dividends earned but not received; and (ii) net sold or purchased investments, but not settled.

There were no recurring fair value measurements classified as Level 3 as of December 31, 2024 (Successor) and December 31, 2023 (Successor).

Nonrecurring Fair Value Measurements

There were no nonrecurring fair value measurements related to impairments of long-lived assets during the year ended December 31, 2024 (Successor) and for the period from May 18 through December 31, 2023 (Successor). See Note 4 for information on the nonrecurring fair value measurements resulting in the application of fresh start accounting and Note 10 for information on the nonrecurring fair value measurement of Brandon Shores during the period from January 1 through May 17, 2023 (Predecessor).

Reported Fair Value

The carrying value of certain financial assets and liabilities on the Consolidated Balance Sheets, including “Cash and cash equivalents,” “Restricted cash and cash equivalents,” “Accounts receivable,” and “Accounts payable and other accrued liabilities” approximate fair value.

The fair value measurements of indebtedness are classified as Level 2 within the fair value hierarchy. The fair value of fixed rate debt was estimated primarily by utilizing an income approach whereby the future cash flows of the obligations are discounted at the estimated current cost of funding rates, which incorporates the credit risk associated with the obligations. The carrying value of variable rate indebtedness approximates fair value.

The carrying value and fair value of indebtedness presented on the Consolidated Balance Sheets were:


	Successor
	December 31, 2024				December 31, 2023
	Carrying Value		Fair Value		Carrying Value		Fair Value

Long-term debt (a)	$	3,004	$	3,120	$	2,820	$	2,934
Other short-term indebtedness (b)	—		—		6		6

__________________

(a)Aggregate value of “Long-term debt” and “Long-term debt, due within one year” presented on the Consolidated Balance Sheets.

(b)Presented as “Other current liabilities” on the Consolidated Balance Sheets.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 107
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-107

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	These Annual Financial Statements, which are prepared in accordance with GAAP, include: (i) the accounts of all controlled subsidiaries; (ii) elimination adjustments for intercompany transactions between controlled subsidiaries; (iii) any undivided interests in jointly owned facilities consolidated on a proportionate basis; and (iv) all adjustments considered necessary for a fair presentation of the information set forth. All adjustments are of a normal recurring nature except as otherwise disclosed. Talen Energy Corporation is a holding company whose only material businesses and properties are held through its direct and wholly owned subsidiary, Talen Energy Supply. Certain of TES’s debt agreements include covenants that restrict the payment of dividends or other distributions to TEC, restricting in excess of 25% of TEC’s consolidated net assets. Accordingly, these condensed unconsolidated financial statements and related footnotes have been prepared in accordance with Sections 5-04 and 12-04 of Regulation S-X. These statements should be read in conjunction with the Annual Financial Statements. In May 2023, TEC and the majority of its subsidiaries emerged from the Restructuring and adopted fresh start accounting. See Notes 2, 3, and 4 to the Annual Financial Statements for additional information regarding the Restructuring and related accounting. Unconsolidated financial results are presented for TEC for the Successor periods for the year ended December 31, 2024 and the period from May 18 through December 31, 2023. Because the results presented in the Annual Financial Statements for Predecessor periods (prior to May 18, 2023) represent the operating results TES, such results are not repeated here. TEC held no cash nor had any cash activity during the year ended December 31, 2024 and the period from May 18 through December 31, 2023; therefore, a statement of cash flows has not been included. Pursuant to the Internal Revenue Code, TEC and TES are each taxable entities. TEC files a consolidated U.S. federal income tax return on behalf of all its subsidiaries. The provision for income taxes and the effect of any recognition and (or) remeasurement are recognized as if: (i) TES and its subsidiaries file a consolidated income tax return; and (ii) TEC files a standalone income tax return. Additionally, the Company has elected to present accrued excise tax liabilities as a result of the repurchase of TEC common stock on the TES consolidated balance sheets. Accordingly, substantially all income taxes are recognized at TES.
Principles of Consolidation/ Consolidation of an Affiliate’s Subsidiary	These Annual Financial Statements, which are prepared in accordance with GAAP, include: (i) the accounts of all controlled subsidiaries; (ii) elimination adjustments for intercompany transactions between controlled subsidiaries; (iii) any undivided interests in jointly owned facilities consolidated on a proportionate basis; and (iv) all adjustments considered necessary for a fair presentation of the information set forth. All adjustments are of a normal recurring nature except as otherwise disclosed. In September 2022, as part of a settlement of certain matters in the Restructuring, TES exchanged preferred units in subsidiaries of Cumulus Digital for common units in Cumulus Digital. Following the consummation of the exchange and other related transactions, TES became the primary beneficiary of Cumulus Digital, a variable interest entity, due to its ability to control the activities that most significantly impacted Cumulus Digital. Accordingly, Cumulus Digital and its subsidiaries were consolidated by TES as of September 30, 2022. The difference between (i) the fair value of Cumulus Digital and its subsidiaries; and (ii) the carrying value of the preferred units immediately before the exchange resulted in a loss of $170 million presented as “Consolidation of subsidiary gain (loss)” on the Consolidated Statements of Operations for the year ended December 31, 2022 (Predecessor).
Emergence from Restructuring, Fresh Start Accounting, and Reverse Acquisition	In May 2022, TES and 71 of its subsidiaries voluntarily commenced the Restructuring under Chapter 11 of the U.S. Bankruptcy Code. TEC joined the Restructuring in December 2022. The Plan of Reorganization was approved by the requisite parties and confirmed by the bankruptcy court in late 2022, and was consummated and became effective in May 2023, when TEC, TES, and the other debtors emerged from the Restructuring. Upon commencement of the Restructuring, TES was deconsolidated from TEC for financial reporting purposes because TEC no longer controlled TES. TEC regained control of TES at Emergence, which resulted in TEC’s reconsolidation of TES. The combination was accounted for as a reverse acquisition in which TEC was the legal acquirer and TES was the accounting acquirer. Accordingly, these Annual Financial Statements are issued under the name of TEC, the legal parent of TES and accounting acquiree, but represent the continuation of the financial statements of TES, the accounting acquirer. After Emergence, TES applied fresh start accounting, which resulted in a new basis of accounting, as the Company became a new financial reporting entity. As a result of the application of fresh start accounting and the implementation of the Plan of Reorganization, our financial position and results of operations beginning after Emergence are not comparable to our financial position or results of operations prior to that date. The financial results are presented for: (i) the Predecessor periods from January 1 through May 17, 2023 (Predecessor) and the year ended December 31, 2022 (Predecessor); and (ii) the Successor periods from May 18 through December 31, 2023 (Successor) and the year ended December 31, 2024 (Successor). These Annual Financial Statements and notes hereto have been presented with a black line division to delineate the lack of comparability between the Predecessor and Successor
Reclassifications	Certain amounts in the prior period financial statements were reclassified to conform to the current period’s presentation. The reclassifications did not affect operating income, net income, total assets, total liabilities, net equity, or cash flows.
Use of Estimates	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Restructuring Effects	Income, expenses, gains, or losses that were incurred or realized as a direct result of the Restructuring since entering bankruptcy proceedings are presented as “Reorganization income (expense), net” on the Consolidated Statements of Operations.
Fair Value of Financial Instruments and Derivatives	We carry a portion of our assets and liabilities at fair value that are measured at a reporting date using an exit price (i.e., the price that would be received to sell an asset or paid to transfer a liability). An exit price may be developed under a market approach utilizing market transactions, an income approach utilizing present value techniques, or a replacement cost approach. The exit prices are disclosed according to the quality of valuation inputs under a three-tiered hierarchy comprised of: (i) Level 1 inputs that are quoted prices (unadjusted) in active markets for identical assets or liabilities; (ii) Level 2 inputs that are other than quoted prices that are directly or indirectly observable; and (iii) Level 3 inputs are unobservable inputs for assets or liabilities.The classification of an asset or liability is based on the lowest level of input significant to its fair value. Those initially classified as Level 3 are subsequently reported as Level 2 when the fair value derived from unobservable inputs is inconsequential to the overall fair value, or if corroborated market data becomes available. Those initially classified as Level 2 are subsequently reported as Level 3 if corroborated market data is no longer available. Transfers occur at the end of the reporting period.
Revenues	Operating revenues on the Consolidated Statements of Operations are primarily comprised of items presented as: (i) “Capacity revenues;” (ii) “Energy and other revenues;” and (iii) “Unrealized gain (loss) on derivative instruments” for certain electricity contracts. Capacity revenues. Includes amounts earned from auctions in ISOs and RTOs and under bilateral contracts to provide available generation capacity that is needed to satisfy system reliability and integrity requirements. Capacity revenues are recognized ratably over the PJM Capacity Year by Talen-owned generation facilities that participate in the auctions and stand ready to deliver generated power. Capacity revenues are based on invoiced amounts corresponding directly to the value provided over a specific time interval. Energy and other revenues. Energy revenues primarily include: (i) amounts earned from sales to ISOs and RTOs for electric generation and ancillary services products that support transmission and grid operations; (ii) amounts earned for wholesale electricity sales to bilateral counterparties; and (iii) realized gains and losses on commodity derivative instruments. Sales of each electric generation and ancillary services to ISOs and RTOs represent performance obligations recognized over time based on volumes delivered or services performed at contractually agreed upon day-ahead or real-time market prices. Sales of wholesale electricity to bilateral counterparties represent performance obligations recognized over a contractually agreed period of time based on volumes delivered at the contractually agreed price. Sales of electric generation, ancillary services, and wholesale electricity to bilateral counterparties are recognized based on invoiced amounts which corresponds directly with the value provided over a specific time interval. Certain contracts constitute bundled agreements to sell energy, capacity, and (or) ancillary services. In such cases, all performance obligations are deemed to be delivered and (or) performed at the same time. Accordingly, as the timing of revenue recognition for all performance obligations is the same and occurs over a contractually agreed period of time, it is unnecessary to allocate transaction price to multiple performance obligations. Realized gains and losses on commodity derivative instruments include the settlements of financial and physical power transactions utilized for the Company’s commercial risk management objectives. Realized settlements of these derivative instruments are recognized and presented net within “Energy and other revenues” on the Consolidated Statements of Operations based on the delivery period of the underlying contract at contractually agreed prices. See “Energy Expenses” below for additional information on realized gains and losses of derivative instruments presented as “Fuel and energy purchases” on the Consolidated Statements of Operations. Other revenues primarily include: (i) Nuclear PTC revenues; and (ii) Nautilus revenues from Bitcoin mining.
Nuclear PTC	The Nuclear PTC program provides qualified nuclear power generation facilities with transferable credits for electricity produced and sold to an unrelated party during each tax year. These credits, which are accounted for by analogy to income-based grants under international accounting standards for government grants and disclosure of government assistance, are recognized when there is reasonable assurance that the Company will comply with the applicable conditions and that the credit will be received, which is generally over the period of production. As the credits that are generated each tax year are based on annual gross receipts and production volumes, the measurement of the credit value is estimated at each period until the final value can be determined at the end of the year, which may be different than the estimated amount. The credit value includes a five-times multiplier (up to $15 per MWh) for meeting prevailing wage requirements. Accordingly, Nuclear PTCs are recognized based on production volumes generated during the period and measured at the credit value for the tax year. See Note 6 for amounts recognized, which are presented as “Energy and other revenues” on the Consolidated Statements of Operations and “Other current assets” on the Consolidated Balance Sheets. Credits that are utilized to reduce federal income taxes payable are presented as a reduction of “Other current liabilities” on the Consolidated Balance Sheets. There have been no transfers of Nuclear PTCs to third parties during the year ended December 31, 2024 (Successor). Additional guidance expected to be issued from the U.S. Treasury and IRS may impact the credit value recognized.
Energy Expenses	Energy expenses on the Consolidated Statements of Operations are primarily comprised of items presented as: (i) “Fuel and energy purchases;” (ii) “Nuclear fuel amortization;” and (iii) “Unrealized gain (loss) on derivative instruments” for certain commodity purchase contracts. Fuel and energy purchases. Primarily includes: (i) fuel costs; (ii) environmental product costs; and (iii) realized gain (loss) on commodity derivative instruments. Fuel costs include the costs incurred by Talen-owned generation facilities for the conversion of natural gas, coal, and (or) oil products to electricity. Fuel for electric generation from natural gas purchases are recognized at the agreed price for natural gas delivered to the applicable generation facility over a contractually agreed period of time. Fuel for electric generation from coal and oil product inventories are recognized at the applicable weighted average inventory cost of volumes consumed. Environmental product costs primarily include RGGIs and other emission product compliance costs that are mandated by certain states. The estimated cost of compliance is accrued at the time an obligation under the applicable terms of each state's environmental compliance program arises. Realized gains and losses on commodity derivative instruments primarily include the settlements of financial and physical fuel contracts utilized for the Company’s commercial risk management objectives. Realized settlements of these derivative instruments are recognized and presented net within “Fuel and energy purchases” on the Consolidated Statements of Operations based on the delivery period of the underlying contract at contractually agreed prices. See “Operating Revenues and Revenue Recognition” above for additional information on realized gains and losses on derivative instruments presented as “Energy and other revenues” on the Consolidated Statements of Operations. Nuclear fuel amortization. Nuclear fuel-related costs, including procurement of uranium, conversion, enrichment, fabrication and assemblies, are capitalized and presented as “Property, plant and equipment, net” on the Consolidated Balance Sheets and presented as a cash outflow within the investing activities section on the Consolidated Statements of Cash Flows. Such costs are amortized as the fuel is consumed using the units-of-production method and presented as “Nuclear fuel amortization” on the Consolidated Statements of Operations.
Unrealized gain (loss) on derivative instruments	Includes unrealized gains and losses resulting from changes in the fair value of certain power contracts that qualify as derivative instruments. See “Derivative Instruments” below for the recognition criteria of unrealized gains and losses on commodity derivative instruments. See “Energy Expenses” below for additional information on unrealized gains and losses of derivative instruments presented as “Energy Expenses” on the Consolidated Statements of Operations.Includes unrealized gains and losses resulting from changes in the fair value of certain fuel contracts and environmental product contracts that qualify as derivative instruments. See “Derivative Instruments” below for the recognition criteria of unrealized gains and losses on commodity derivative instruments. See “Operating Revenues and Revenue Recognition” above for additional information on unrealized gains and losses of derivative instruments presented as “Operating Revenues” on the Consolidated Statements of Operations. Derivative Instruments. The fair value of derivative contracts required to be measured at fair value are presented as “Derivative instruments” within assets or liabilities on the Consolidated Balance Sheets. The primary type of derivative instruments utilized are commodity derivatives. Commodity derivative contracts are valued using inputs and assumptions such as contractual volumes, delivery location, forward commodity prices, commodity price volatility, discount rates, and credit worthiness of counterparties. For derivatives that trade in liquid markets, such as generic forwards, swaps, and options, the inputs and assumptions are generally observable. Such instruments are categorized in Level 2. In most instances, master netting agreements govern derivative transactions between parties and contain certain provisions for setoff rights. The fair value of derivative instruments is presented net of setoff rights and cash collateral deposits. The fair value of commercial contracts that are not subject to netting and (or) collateral provisions is presented gross. Prior to Emergence, the fair value of derivative instruments presented on the Consolidated Balance Sheets was presented gross of setoff rights and cash collateral deposits exchanged between parties under such arrangements. Unrealized gains or losses associated with a derivative instrument that economically hedges certain risks but where qualified cash flow hedge accounting is not elected or not met are presented on the Consolidated Statements of Operations in the period when such gains or losses arise. As there are no derivatives where qualified hedge accounting has been elected, changes in the fair value of commodity derivatives are presented as “Unrealized gain (loss) on derivative instruments,” as a component of either “Operating Revenues” or “Energy Expenses” on the Consolidated Statements of Operations in a manner consistent with the presentation of net realized gains and losses. See “Operating Revenues” and “Energy Expenses” above for a discussion of net realized gains and losses on commodity derivatives. The cumulative net gains or losses for interest rate contracts are presented as “Interest expense and other finance charges” on the Consolidated Statements of Operations.
Operation, Maintenance and Development	The costs of removal, repairs, maintenance, and other operating costs, pre-commercial development activities, and salaries and benefits for operations personnel that each do not meet capitalization criteria are recognized as an expense when incurred. Materials and supplies inventories are recognized as an expense at the weighted average cost of materials consumed as they are used for repairs and maintenance. Costs for pre-commercial development stages of certain projects that are not capitalized as “Property, plant and equipment, net” on the Consolidated Balance Sheets and recurring operational and maintenance activities are each presented as “Operation, maintenance and development” on the Consolidated Statements of Operations. Development expenses incurred are primarily for pre-commercial activities at Nautilus and hyperscale construction activities at Cumulus Digital.
Stock-Based Compensation	TEC grants performance stock units (“PSUs”) and restricted stock units (“RSUs”) to certain employees and non-employee directors. The fair value of PSUs is estimated on the grant date utilizing a Monte Carlo Valuation Model, which contains significant unobservable inputs that are believed to be consistent with those used by principal market participants. The fair value of RSUs is derived from the closing price of TEC common stock at the grant date. Forfeitures are recognized as they occur. Unvested PSUs and RSUs are entitled to dividends or dividend equivalents, which are accrued and distributed to award recipients at the time such awards vest. Dividends and dividend equivalents are subject to the same vesting and forfeiture provisions as the underlying awards. Stock-based compensation expense is recognized for both graded and cliff vesting awards on a straight-line basis over the requisite service period for the entire award. Stock-based compensation expense is presented as “General and administrative” on the Consolidated Statements of Operations.
Income Taxes	TEC and its subsidiaries file a consolidated U.S. federal income tax return. Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying values of existing assets and liabilities and their respective tax basis, tax credits and NOL carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities due to a change in tax rates is recognized as income in the period that includes the enactment date. Valuation allowances are recognized to reduce deferred tax assets to the extent necessary to result in an amount that is more likely than not to be realized. Disproportionate income tax effects are removed from AOCI when the circumstance upon which they are premised ceases to exist. The financial statement effect of a tax position is recognized when it is more-likely-than-not, based on the technical merits, that the position will be sustained upon examination. A tax position that meets the more-likely-than-not recognition threshold is measured as the largest amount of tax benefit that is greater than 50% likely of being realized upon ultimate settlement with a taxing authority. A previously recognized tax position is reversed in the first period in which it is no longer more-likely-than-not that the tax position would be sustained upon examination. Interest and penalties from tax uncertainties are presented as “Income tax benefit (expense)” on the Consolidated Statements of Operations.
Loss Contingencies	Potential losses are accrued when: (i) information is available that indicates it is probable (i.e., likely to occur) that a loss has been incurred, given the likelihood of the uncertain future events; and (ii) the amount of the loss can be reasonably estimated. We continuously assess potential loss contingencies for environmental remediation, litigation claims, regulatory penalties and other events. Loss contingencies are discounted when appropriate. Legal costs are expensed as incurred. Management continuously assesses potential loss contingencies for environmental remediation, litigation claims, regulatory penalties and other events. Potential losses are accrued when: (i) information is available that indicates it is probable (i.e., likely to occur) that a loss has been incurred, given the likelihood of the uncertain future events; and (ii) the amount of the loss can be reasonably estimated. Loss contingencies are recognized at management's best estimate, which may be discounted, where appropriate. Loss contingencies exclude estimates for any legal fees, which are recognized as incurred when the legal services are performed.
Concentrations of Credit Risk	Concentrations of credit risk exist primarily within cash and cash equivalents, receivables, and commodity derivative assets. Cash and cash equivalents are generally held in accounts where the amounts deposited exceed the maximum deposit insurance provided by the Federal Deposit Insurance Corporation. Cash and cash equivalents and restricted cash balances are primarily deposited in accounts with major financial institutions with investment grade credit ratings. In certain instances, funds are invested in highly liquid U.S. Treasury securities or other obligations with original maturities of less than 90 days that are issued by or guaranteed by the U.S. Government. Concentrations of credit risk for receivables are primarily attributable to entities that reimburse Talen for certain capital expenditures and operating costs associated with jointly owned facilities. Concentrations of credit risk for commodity derivative assets are primarily attributable to unaffiliated investment grade counterparties which engage in energy marketing activities with Talen Energy Marketing.
Cash and Cash Equivalents	Bank deposits, liquid investments, and other similar assets with original maturities of three months or less. Bank deposits, commodity exchange deposits, liquid investments, and other similar assets with original maturities of three months or less that are restricted by agreement are presented as “Restricted cash and cash equivalents” on the Consolidated Balance Sheets.
Accounts Receivable	Receivables primarily consist of amounts due from customers or other contract counterparties, net of any collection allowances. Uncollected receivables greater than 30 days past due are assessed for collectability based on a variety of factors that include, but are not limited to, customer credit worthiness, duration receivables are outstanding, and (or) historical collection experience. Management continuously assesses and considers current economic trends that might impact the amount of future credit losses. Additionally, if it becomes known that a specific customer may have the inability to settle its obligation that is not yet past due, such receivables are assessed for collectability. If these assessments indicate a receivable collection is remote, its carrying value is reduced through an allowance for doubtful accounts measured at management’s best estimate, and a charge is presented on the Consolidated Statements of Operations. If any portion of the original carrying value of the receivable is recovered, the allowance and the associated charge are reversed in the period of collection.
Inventory	Inventory consists of fuel for generation (primarily coal and fuel oil), materials and supplies, and environmental products each of which are valued at the lower of weighted average cost or net realizable value. See Note 8 for additional information on inventory.
Variable Interest Entities	The primary beneficiary (a controlling financial interest) of a VIE is required to consolidate the VIE when it has both: (i) the power to direct the activities that most significantly impact the entity’s economic performance; and (ii) the obligation to absorb losses or receive benefits from the entity that could potentially be significant to the VIE. Talen consolidates a VIE when it is determined that it is the primary beneficiary of the VIE. Investments in entities in which Talen has the ability to exercise significant influence but does not have a controlling financial interest are accounted for under the equity method.
Investments in Debt and Equity Securities	The NDT holds investments in available-for-sale debt securities and equity securities, which are carried at fair value and presented as “Nuclear decommissioning trust funds” on the Consolidated Balance Sheets. Unrealized gains and losses, net of income tax, on available-for-sale debt securities are presented as “Other Comprehensive Income (Loss)” on the Consolidated Statements of Comprehensive Income in the period when such gains and losses arise. Realized gains and losses on available-for-sale debt securities are transferred from AOCI to “Nuclear decommissioning trust funds gain (loss), net” on the Consolidated Statements of Operations in the period when the sale of the security occurs. The specific identification method is used to calculate realized gains and losses on debt and equity securities. If an available-for-sale debt security's fair value declines below cost and the decline is determined to be other-than-temporary, the unrealized loss is recognized on the Consolidated Statements of Comprehensive Income in the period when such determination arises. Unrealized gains and losses and realized gains and losses on equity securities are presented as “Nuclear decommissioning trust funds gain (loss), net” on the Consolidated Statements of Operations in the period when such gains or losses arise.
Property, Plant and Equipment	Expenditures for land, the construction of facilities, the addition or refurbishment of major equipment, and commercially viable new development projects are capitalized at cost. Such capitalized amounts include interest costs, where appropriate. Facilities, land, and other equipment acquired in a business combination is recognized at fair value. In each case, such amounts are presented as “Property, plant and equipment, net” on the Consolidated Balance Sheets. Reductions in the carrying value of PP&E are accumulated over the estimated useful life of each depreciable unit using straight-line or group depreciation methods, where appropriate. Such periodic reduction is presented as a charge to “Depreciation, amortization and accretion” on the Consolidated Statements of Operations. Generally, upon normal retirement of PP&E under the group depreciation method, the costs of such assets are retired against accumulated depreciation in the period of the retirement and no gain or loss is recognized. Any remaining carrying value of PP&E at its retirement date that depreciated under the straight-line depreciation method is presented as a loss within “Other operating income (expense), net” on the Consolidated Statements of Operations. Any remaining carrying value of PP&E at its sale date and any proceeds from the disposition are presented as a gain or loss net on the Consolidated Statements of Operations. Expenditures for intangible assets such as contractual rights, software and licenses are capitalized at cost and are presented as “Property, plant and equipment, net” on the Consolidated Balance Sheets. Reductions in the carrying value of intangible assets with finite useful lives are accumulated over the estimated useful life of each intangible asset using an amortization pattern which reflects the economic benefits of the intangible asset. Such periodic reduction is presented as a charge to “Depreciation, amortization and accretion” on the Consolidated Statements of Operations.
Impairments	PP&E used in operations are assessed for impairment whenever changes in facts and circumstances indicate the carrying value of the asset group may not be recoverable. Indicators of impairment may include changes in the economic environment, negative financial trends, physical damage to assets or decisions of management regarding strategic initiatives. Where applicable, individual assets are grouped for impairment purposes at the lowest level for which there are identifiable cash flows that are largely independent of the cash flows of other assets and liabilities. If there is an indication the carrying value of an asset group may not be recovered, management reviews the expected future cash flows of the asset group. If the sum of the undiscounted pre-tax cash flows is less than the carrying value of the asset group, the asset group is written down to its estimated fair value. Impairment charges are presented as “Impairments” on the Consolidated Statements of Operations in the period in which the impairment condition arises. If facts and circumstances indicate that the carrying value of an asset under construction will have no future economic benefit, such amounts are presented on the Consolidated Statements of Operations in the period in which such projects are abandoned, canceled, or management otherwise determines the costs to be unrecoverable.Fair value may be determined by a variety of valuation methods including third-party appraisals, market prices of similar assets, and present value techniques. However, as there is generally a lack of quoted market prices for long-lived assets, the fair value of impaired assets is typically determined based on the present values of expected future cash flows using discount rates that are believed to be consistent with those used by principal market participants. The estimated cash flows and related fair value computations consider all available evidence at the date of the review, such as estimated future generation volumes, forward capacity and commodity prices, energy prices, operating costs, capital expenditures, and environmental costs.
Asset Retirement Obligations	A liability for an ARO or conditional ARO exists when a legal obligation arises from laws, regulations or other contractual requirements for the retirement of tangible long-lived assets. When an ARO liability is incurred, which is typically at asset construction or through assumption of the liability in connection with a business combination, it is initially recognized at fair value. Fair value measurements are estimated under a present value technique and are discounted using a credit-adjusted risk-free rate. Additionally, given the inherent uncertainty in estimating the amount of cash flows to settle an ARO liability or its settlement date, fair value estimates include a market risk premium and a range of possible cash flow outcomes, where applicable. At the initial recognition, the effects on the Consolidated Balance Sheets include: (i) an increase to “Asset retirement obligations and accrued environmental costs” for the portion of ARO to be settled after one year and (or) “Other current liabilities” for the portion of the ARO to be settled within one year; and (ii) an offsetting increase to “Property, plant and equipment, net” for the asset retirement capitalized cost. Estimated future ARO cash expenditures and settlement dates are reviewed periodically to identify any required amendments to the carrying value of each ARO liability. ARO liabilities increase over a period of time through the recognition of accretion expense to recognize changes in the obligation due to the passage of time. The asset retirement capitalized cost is depreciated at a rate consistent with the useful life of the associated long-lived asset. The depreciation of the asset retirement capitalized cost and the accretion of the ARO liability are each presented as “Depreciation, amortization and accretion” on the Consolidated Statements of Operations. An ARO liability amendment associated with a long-lived asset that is not fully impaired or depreciated is recognized through an adjustment to the ARO liability and the asset retirement capitalized cost. Any revision to the asset retirement capitalized cost is generally depreciated over the remaining life of the associated long-lived asset. An ARO liability amendment associated with a fully impaired or depreciated asset is presented as “Other operating income (expense), net” on the Consolidated Statements of Operations. At settlement, a gain or loss will arise if the cash expenditures to settle the ARO liabilities are different than the carrying values. Such gains or losses are presented as “Other operating income (expense), net” on the Consolidated Statements of Operations. A conditional ARO refers to an entity’s legal obligation to perform an asset retirement activity in which the timing or method of settlement is conditional on a future event that may or may not be within the entity’s control, including legal or regulatory requirements. There may also be instances when there is no available information regarding the ultimate ARO settlement timing or the fair value of the obligation may not be reasonably estimable. If sufficient information becomes available to reasonably estimate the fair value of the liability for an ARO or a conditional ARO, a liability is recognized in the period in which it is determined.
Debt	Proceeds received on the issuance of new term loans, secured notes, unsecured notes, bonds, and similar indebtedness are presented as “Long-term debt” or “Long-term debt, due within one year” on the Consolidated Balance Sheets. Interest incurred as paid-in-kind, whether accrued or capitalized as additional principal are presented as “Long-term debt” with the associated outstanding amounts of indebtedness. Costs incurred to issue new indebtedness and any original issuance discounts or premiums are deferred at issuance on the Consolidated Balance Sheets and presented together with the associated outstanding principal amounts of indebtedness. Interest accrues on outstanding principal amounts of indebtedness based on contractually determined rates during each period. Costs incurred for the issuance of indebtedness and any original issuance discounts or premiums are subsequently amortized through the expected maturity date of the associated indebtedness under the effective interest rate method and are presented as “Interest expense and other finance charges” on the Consolidated Statements of Operations. Gains and losses on the: (i) early redemption of indebtedness; or (ii) early termination and (or) reduction of revolving credit facility committed capacity are presented as a gain or loss on the Consolidated Statements of Operations. Such amounts include the proportional derecognition of any deferred financing costs, fees, discounts, and (or) premiums associated with the indebtedness. Direct cash borrowings under secured lines of credit, revolving credit facilities, and similar indebtedness are presented as a current liability on the Consolidated Balance Sheets. Costs incurred to issue new arrangements are deferred and presented as “Other current assets” or “Other noncurrent assets” on the Consolidated Balance Sheets. Interest accrues on direct cash borrowings and LCs based on contractually determined rates during each period. Costs incurred to issue new arrangements are subsequently amortized through the expected expiration of the associated arrangement under the straight-line method. Commitment fees on available but unused credit facility capacity are expensed as incurred. Such costs are presented as “Interest expense and other finance charges” on the Consolidated Statements of Operations.
Postretirement Benefit Obligations	Certain Talen subsidiaries sponsor various defined benefit pension plans and other postretirement benefit plans. Gains and losses, net of income tax, that arise and are not a component of net periodic defined benefit costs are presented as “Other Comprehensive Income (Loss)” on the Consolidated Statements of Comprehensive Income. Following Emergence, actuarial gains and losses in excess of the greater of 10% of the plan's projected benefit obligation or the market-related value of plan assets are amortized over (i) the expected average remaining service period of active plan participants for active plans; or (ii) the average future remaining lifetime of the plan participants of frozen plans. Prior to Emergence, Talen used an accelerated amortization method for the recognition of gains and losses for defined benefit pension plans: (i) actuarial gains and losses in excess of 30% of the plan's projected benefit obligation are amortized on a straight-line basis over one-half of the expected average remaining service of active plan participants; and (ii) actuarial gains and losses in excess of 10% of the greater of the plan's projected benefit obligation or the market-related value of plan assets and less than 30% of the plan's projected benefit obligation are amortized on a straight-line basis over the expected average remaining service period of active plan participants. Following Emergence, a spot rate curve that represents a portfolio of high-quality corporate bonds is used to develop the discount rate utilized to measure the projected benefit obligations and service costs for benefit plans. Prior to Emergence, a bond matching methodology was utilized, based on a specific portfolio of bonds that closely match the overall cash flow timing and duration of the benefit plans. Talen is obligated to provide health care benefits under the Coal Act and pneumoconiosis (black lung) benefits under the Black Lung Act for retired miners and eligible beneficiaries. Benefits are funded from a Voluntary Employees’ Benefit Association (“VEBA”) trust and a trust maintained under certain federal and state black lung legislation. Shortfalls in funded status of the plans are assessed as contingent liabilities. As such, Talen recognizes funding shortfalls on its balance sheet, where applicable, if benefit obligations of either plan exceed the fair value of available trust assets.
Treasury Stock and Retirement of Treasury Shares	Share repurchases are accounted for under the cost method, which recognizes the entire cost of the acquired stock, including transaction costs and excise tax, as a reduction in additional paid-in-capital and are presented as “Treasury stock” on the Consolidated Balance Sheets. Share repurchases are recognized on a trade date basis when we are contractually obligated to purchase the shares. Treasury shares are retired on the settlement date of the transaction. At retirement, the common stock balance is reduced for the par value of the shares. The excess of the acquisition cost of repurchased shares over the par value is recognized in additional paid-in capital (up to the amount credited to additional paid-in capital upon original issuance of the shares), with any remaining cost deducted from retained earnings.
Recently Adopted Accounting Pronouncements/ Recent Accounting Pronouncements Not Yet Adopted	Recently Adopted Accounting Pronouncements ASU 2023-07. In November 2023, the Financial Accounting Standards Board (the “FASB”) issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. This ASU requires enhanced disclosures about significant segment expenses. The ASU is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted. The Company adopted the fiscal year disclosure requirements for this ASU beginning January 1, 2024, and will adopt interim period disclosure requirements beginning January 1, 2025. Recent Accounting Pronouncements Not Yet Adopted ASU 2023-09. In December 2023, the FASB issued ASU 2023-09 Income Taxes (Topic 740): Improvements to Income Tax Disclosures. This ASU requires annual disclosures for specific categories in the rate reconciliation and additional information for reconciling items that meet a quantitative threshold. The ASU is effective for fiscal years beginning after December 15, 2024. Early adoption is permitted for annual financial statements that have not yet been issued. The Company is evaluating the disclosure impact of this ASU and expects to adopt it in the required period. ASU 2024-03. In November 2024, the FASB issued ASU 2024-03, Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses. This ASU requires public companies to disclose, in the notes to financial statements, specified information about certain costs and expenses at each interim and annual reporting period. This ASU is effective for annual reporting periods beginning after December 15, 2026. Early adoption is permitted. The Company is evaluating the disclosure impact of this ASU and expects to adopt it in the required period.

Commitments and Contingencies - Certain Resolved Matters (Details) - Settled Litigation - USD ($) $ in Millions	1 Months Ended	5 Months Ended	7 Months Ended	12 Months Ended
	Dec. 31, 2023	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Talen vs TES, TEC, the TERP, and the TERP committee
Other Commitments [Line Items]
Administrative costs related to settlement				$ 6
Legal settlements and litigation costs				$ 14
PPL/Talen Montana Litigation
Other Commitments [Line Items]
Improper payment	$ 733
Proceeds from legal settlements	115
Litigation settlement, amount remitted to GUC trust	11
Litigation settlement, gain					$ 104
Winter Storm Elliott
Other Commitments [Line Items]
Estimated litigation liability	28		$ 28		28
Litigation settlement, penalty amount		$ 13	2		29	$ 33
Remaining derecognized amount	$ 19		$ 19		$ 19

Fresh Start Accounting - Fresh Start Adjustments (Details) - USD ($) $ in Millions		12 Months Ended
	May 17, 2023	Dec. 31, 2024	Dec. 31, 2023
Inventory Adjustments:
Coal		$ 92	$ 152
Oil products		65	75
Materials and supplies, net		88	72
Environmental products		57	76
Inventory, net	$ 307	302	375
Property, plant and equipment, net:
Property, plant and equipment, net (Note 10)	3,864	3,154	3,839
Other noncurrent assets:
Other noncurrent assets	208	183	147
Adjustments to long-term debt:
Long-term debt (Notes 13 and 14)	2,840	$ 2,987	2,811
Fair value adjustments, unfavorable supply contracts	13
Minimum \| Measurement Input, Inflation Rate
Adjustments to long-term debt:
Fair value adjustments, asset retirement obligation, percentage		2.00%
Minimum \| Measurement Input, Risk Free Interest Rate
Adjustments to long-term debt:
Fair value adjustments, asset retirement obligation, percentage		8.00%
Fair value adjustments, asset retirement obligation, estimated period		5 years
Maximum \| Measurement Input, Inflation Rate
Adjustments to long-term debt:
Fair value adjustments, asset retirement obligation, percentage		3.00%
Maximum \| Measurement Input, Risk Free Interest Rate
Adjustments to long-term debt:
Fair value adjustments, asset retirement obligation, percentage		12.00%
Fair value adjustments, asset retirement obligation, estimated period		20 years
Fresh Start Adjustments
Inventory Adjustments:
Coal	(33)
Oil products	11
Materials and supplies, net	(133)
Environmental products	14
Inventory, net	(141)
Property, plant and equipment, net:
Property, plant and equipment, net (Note 10)	(458)
Other noncurrent assets:
Favorable supply contracts	109
Fair value adjustment to equity method investments	3
Eliminate debt issuance costs associated with debtor-in-possession credit facilities	(29)
Fair value reduction to other miscellaneous assets	(9)
Other noncurrent assets	74
Adjustments to long-term debt:
Eliminate debt issuance costs associated with prepetition secured notes, prepetition TLB and LMBE-MC TLB	48
Fair value adjustment to Cumulus Digital TLF	11
Fair value adjustment to LMBE-MC TLB	(4)
Long-term debt (Notes 13 and 14)	55
Electric generation
Property, plant and equipment, net:
Property, plant and equipment, net (Note 10)		$ 2,738	3,069
Electric generation \| Fresh Start Adjustments
Property, plant and equipment, net:
Property, plant and equipment, net (Note 10)	(350)
Other property and equipment
Property, plant and equipment, net:
Property, plant and equipment, net (Note 10)		72	337
Other property and equipment \| Fresh Start Adjustments
Property, plant and equipment, net:
Property, plant and equipment, net (Note 10)	(80)
Intangible assets \| Fresh Start Adjustments
Property, plant and equipment, net:
Intangible assets	(65)
Capitalized software
Property, plant and equipment, net:
Property, plant and equipment, net (Note 10)		5	5
Capitalized software \| Fresh Start Adjustments
Property, plant and equipment, net:
Property, plant and equipment, net (Note 10)	(3)
Construction work in progress
Property, plant and equipment, net:
Property, plant and equipment, net (Note 10)		$ 169	$ 255
Construction work in progress \| Fresh Start Adjustments
Property, plant and equipment, net:
Property, plant and equipment, net (Note 10)	$ 40

Stockholders' Equity - Pre-tax Gains (Losses) Reclassified from AOCI (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Nuclear decommissioning trust funds gain (loss), net	$ 57	$ 108	$ 178	$ (184)
Depreciation, amortization and accretion	(200)	(165)	(298)	(520)
Operation, maintenance and development	(285)	(358)	(592)	(610)
Other non-operating income (expense), net	10	95	61	(44)
Income (loss) before income taxes	677	194	1,111	(1,328)
Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income (loss) before income taxes	(5)	(7)	0	(59)
Reclassification out of Accumulated Other Comprehensive Income \| Available-for-sale securities unrealized gain (loss), net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Nuclear decommissioning trust funds gain (loss), net	(4)	(7)	(1)	(33)
Reclassification out of Accumulated Other Comprehensive Income \| Qualifying derivatives unrealized gain (loss), net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Depreciation, amortization and accretion	1	0	0	2
Reclassification out of Accumulated Other Comprehensive Income \| Postretirement benefit prior service credits (costs), net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Operation, maintenance and development	0	0	1	(1)
Reclassification out of Accumulated Other Comprehensive Income \| Postretirement benefit actuarial gain (loss), net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other non-operating income (expense), net	$ (2)	$ 0	$ 0	$ (27)

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Numerator: (Millions of Dollars)
Net Income (Loss)	$ 465	$ 143	$ 1,013	$ (1,293)
Less:
Net income (loss) attributable to noncontrolling interest	(14)	9	15	(4)
Net Income (Loss) Attributable to Stockholders (Successor) / Member (Predecessor)	$ 479	$ 134	$ 998	$ (1,289)
Denominator: (Thousands)
Weighted-average shares outstanding - Basic (in shares)	0	59,029,000	54,254,000	0
Warrants (in shares)	0	84,000	0	0
Weighted-average shares outstanding - Diluted (in shares)	0	59,399,000	56,486,000	0
Earnings per Share - Basic (in dollars per share)		$ 2.27	$ 18.40
Earnings per Share - Diluted (in dollars per share)		$ 2.26	$ 17.67
Antidilutive shares (in shares)			0
Performance stock units
Denominator: (Thousands)
Antidilutive shares (in shares)		134,798
Restricted stock units
Denominator: (Thousands)
Stock units (in shares)	0	166,000	354,000	0
Performance stock units
Denominator: (Thousands)
Stock units (in shares)	0	120,000	1,878,000	0

Schedule I - Condensed Financial Information of Registrant (Tables)

12 Months Ended

Dec. 31, 2024

Condensed Financial Information Disclosure [Abstract]

Schedule of Condensed Financial Statements


	Successor
(Millions of Dollars, except share data)	Year Ended December 31, 2024		May 18 through December 31, 2023
Operating Revenue	$	—	$	—
Operating Expenses	—		—
Operating Income	—		—
Equity in earnings of TES	998		134
Income (Loss) Before Income Taxes	998		134
Income tax benefit (expense)	—		—
Net Income (Loss)	998		134
Other comprehensive income (loss)	11		(23)
Comprehensive Income (Loss)	$	1,009	$	111
Earnings Per Share of Common Stock:
Net Income (Loss) Attributable to Stockholders - Basic	$	18.40	$	2.27
Net Income (Loss) Attributable to Stockholders - Diluted	$	17.67	$	2.26
Weighted-Average Number of Common Shares Outstanding - Basic (in thousands)	54,254		59,029
Weighted-Average Number of Common Shares Outstanding - Diluted (in thousands)	56,486		59,399


	Successor
(Millions of Dollars, except share data)	December 31, 2024		December 31, 2023
Assets
Investment in TES	$	1,387	$	2,457
Total Assets	$	1,387	$	2,457




Total Liabilities	$	—	$	—

Stockholders’ Equity
Common stock ($0.001 par value, 350,000,000 shares authorized) (a)	—		—
Additional paid-in capital	1,725		2,346
Accumulated retained earnings (deficit)	(326)		134
Accumulated other comprehensive income (loss)	(12)		(23)
Stockholders’ Equity	1,387		2,457
Total Liabilities and Stockholders’ Equity	$	1,387	$	2,457

__________________

(a)Shares issued and outstanding were 45,961,910 and 59,028,843 as of December 31, 2024 (Successor) and December 31, 2023 (Successor), respectively.

Acquisitions and Divestitures - 2024 and 2023 Activities (Details) $ in Millions	1 Months Ended				5 Months Ended	6 Months Ended	7 Months Ended	12 Months Ended
	May 31, 2024 USD ($) MW	Mar. 31, 2024 USD ($)	Apr. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	May 17, 2023 USD ($)	Aug. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2022 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture					$ 0		$ 0	$ 1,398	$ 0
Gain (loss) on sale of assets, net					0		$ 0	886	$ 0
ERCOT Assets \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Power generating capacity \| MW	1,710
Proceeds from divestiture	$ 785
Gain (loss) on sale of assets, net								564
AWS Data Campus \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture		$ 350				$ 650
Gain (loss) on sale of assets, net								$ 324
Funding of professional fees escrow account		$ 300
Western Gas Book \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture			$ 15
Gain (loss) on sale of assets, net					15
Pennsylvania Minerals \| Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture				$ 29
Gain (loss) on sale of assets, net					$ 29

Postretirement Benefit Obligations - Narrative (Details) - USD ($) $ in Millions	1 Months Ended		5 Months Ended	7 Months Ended	12 Months Ended
	Sep. 30, 2024	Mar. 31, 2024	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024
Defined Benefit Plan Disclosure [Line Items]
Excess assets from PA Mines UMWA Plan VEBA		$ 10
Gain on transfer of excess assets					$ 10
Postretirement benefit prior service (credits) costs, net (Note 15)	$ 21
Actual benefits paid			$ 38	$ 60	114
Net periodic defined benefit cost (credit)			10	9	$ 25
Maximum
Defined Benefit Plan Disclosure [Line Items]
Alternative and other investments, limited life span					15 years
Minimum
Defined Benefit Plan Disclosure [Line Items]
Alternative and other investments, limited life span					10 years
Certain Other Postretirement Benefit Plans
Defined Benefit Plan Disclosure [Line Items]
Overfunded Status				33	$ 36
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Overfunded Status			(274)	(333)	(291)
Employer contributions			2	9	54
Actual benefits paid			34	55	105
Pension Benefits \| TES Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions			0	5	43
Expected future employer contributions, next fiscal year					65
Pension Benefits \| Talen Montana Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions			$ 2	$ 4	10
Expected future employer contributions, next fiscal year					4
Employer discretionary contribution amount					$ 8

Schedule I - Condensed Financial Information of Registrant - Condensed Unconsolidated Statements of Comprehensive Income (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Condensed Financial Statements, Captions [Line Items]
Operating Revenue	$ 1,210	$ 1,344	$ 2,115	$ 3,089
Operating Income (Loss)	(76)	160	226	241
Income (loss) before income taxes	677	194	1,111	(1,328)
Income tax benefit (expense)	(212)	(51)	(98)	35
Net Income (Loss)	465	143	1,013	(1,293)
Other comprehensive income (loss)	6	(23)	11	(15)
Comprehensive Income (Loss)	$ 471	$ 120	$ 1,024	$ (1,308)
Net Income (Loss) Attributable to Stockholders - Basic (in dollars per share)		$ 2.27	$ 18.40
Net Income (Loss) Attributable to Stockholders - Diluted (in dollars per share)		$ 2.26	$ 17.67
Weighted-average shares outstanding - Basic (in shares)	0	59,029	54,254	0
Weighted-Average Number of Common Shares Outstanding - Diluted (in shares)	0	59,399	56,486	0
Parent Company
Condensed Financial Statements, Captions [Line Items]
Operating Revenue		$ 0	$ 0
Operating Expenses		0	0
Operating Income (Loss)		0	0
Equity in earnings of TES		134	998
Income (loss) before income taxes		134	998
Income tax benefit (expense)		0	0
Net Income (Loss)		134	998
Other comprehensive income (loss)		(23)	11
Comprehensive Income (Loss)		$ 111	$ 1,009
Net Income (Loss) Attributable to Stockholders - Basic (in dollars per share)		$ 2.27	$ 18.40
Net Income (Loss) Attributable to Stockholders - Diluted (in dollars per share)		$ 2.26	$ 17.67
Weighted-average shares outstanding - Basic (in shares)		59,029	54,254
Weighted-Average Number of Common Shares Outstanding - Diluted (in shares)		59,399	56,486

Long-term Debt and Other Credit Facilities - Narrative (Details) - USD ($) $ in Millions	1 Months Ended			5 Months Ended	7 Months Ended	12 Months Ended
	Jan. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
LCs Issued				$ 0
Covenant consolidated series step-ups first lien net leverage ratio		4.25				4.25
Total principal		$ 3,038			$ 2,849	$ 3,038	$ 2,849
Repayments of debt				0	0	0		$ 62
Letter of Credit
Debt Instrument [Line Items]
LCs Issued		374				374
Letter of Credit
Debt Instrument [Line Items]
Letters of credit terminated			$ 133
Secured Debt \| Subsequent Event
Debt Instrument [Line Items]
Maximum amount available to redeem	10.00%
Debt instrument, redemption price, percentage	103.00%
LCF \| Letter of Credit
Debt Instrument [Line Items]
LCs Issued		297				297
LCF \| Secured Debt
Debt Instrument [Line Items]
Total principal		900				$ 900
Commitment percentage						2.00%
Fronting fee percentage						0.125%
TLC LCF and Bilateral LCF \| Letter of Credit
Debt Instrument [Line Items]
LCs Issued					478		$ 478
TLC LCF \| Letter of Credit \| Letter of Credit
Debt Instrument [Line Items]
Debt instrument, collateral							472 million
TLC LCF \| Secured Debt
Debt Instrument [Line Items]
Letters of credit terminated		470
RCF \| Revolving Credit Facility
Debt Instrument [Line Items]
Minimum percentage exceeding revolving commitments						50.00%
RCF \| Secured Debt
Debt Instrument [Line Items]
Total principal		$ 700				$ 700
Reduction in interest rate		1.00%
Interest rate		(2.00%)
Increase in borrowing capacity		$ 475				475
Maximum borrowing capacity		700				700
Secured ISDAs \| Secured Debt
Debt Instrument [Line Items]
Total principal		17				17
TLB-2 \| Secured Debt
Debt Instrument [Line Items]
Total principal		$ 850			0	$ 850	$ 0
Interest rate		7.02%				7.02%
TLB-1 \| Secured Debt
Debt Instrument [Line Items]
Total principal		$ 857		580	866	$ 857	866
Reduction in interest rate		1.00%
Interest rate		(2.50%)				(2.50%)
Interest rate		7.02%				7.02%
TLC \| Secured Debt
Debt Instrument [Line Items]
Total principal		$ 0		$ 470	470	$ 0	470
Repayments of debt		470
Bilateral LCF \| Secured Debt
Debt Instrument [Line Items]
Letters of credit terminated		75
PEDFA 2009B Bonds \| Bonds
Debt Instrument [Line Items]
Total principal		$ 50	$ 50		50	$ 50	50
Interest rate		5.25%	5.25%			5.25%
PEDFA 2009C Bonds \| Bonds
Debt Instrument [Line Items]
Total principal		$ 81	$ 81		$ 81	$ 81	$ 81
Interest rate		5.25%	5.25%			5.25%

Postretirement Benefit Obligations - Target Allocations (Details)	Dec. 31, 2024
Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations	100.00%
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations	100.00%
Growth portfolio \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations	48.00%
Debt Securities, Growth Portfolio \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations	10.00%
Other Securities, Growth Portfolio \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations	7.00%
Immunizing portfolio \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations	47.00%
Debt Securities, Immunizing Portfolio \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations	35.00%
Other Securities, Immunizing Portfolio \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations	12.00%
Liquidity portfolio \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations	4.00%
Cash and cash equivalents \| Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations	4.00%
Equity securities \| Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations	11.00%
Equity securities \| Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations	32.00%
Debt securities \| Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target allocations	84.00%

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Income Taxes - Narrative (Details) MWh in Millions, $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2024 USD ($) MWh $ / mWh Rate	Dec. 31, 2022 USD ($)
Income Tax Disclosure [Abstract]
Cancellation Of Indebtedness Income \| $			$ 1,200
Change in valuation allowance \| $	$ (129)	$ 43	$ (128)	$ 198
Nuclear power generation facilities produced and sold to unrelated party			3
Nuclear PTC Program, multiplier \| Rate			500.00%
Nuclear PTC Program, maximum (dollars per MWh)			15
Nuclear production tax credit program, minimum per MWh, annual gross receipts (dollars per MWh)			25
Nuclear production tax credit program, multiplier per MWh, threshold for annual gross receipts (dollars per MWh)			43.75
Susquehanna generated and sold to third parties (MWh) \| MWh			17
Current taxes payable \| $		$ 2	$ 53

Commitments and Contingencies - Regulatory Matters (Details)	1 Months Ended
	Dec. 31, 2024 auction filing	Oct. 31, 2024 auction	Jan. 28, 2025 MWd
Other Commitments [Line Items]
Requested delay duration		6 months
Number of scheduled auctions \| auction		4
Number Of FERC filings \| filing	2
Number of delivery years	2 years
Number of auctions \| auction	2
Minimum \| Subsequent Event
Other Commitments [Line Items]
Collar on capacity price \| MWd			175
Maximum \| Subsequent Event
Other Commitments [Line Items]
Collar on capacity price \| MWd			325

Organization and Operations	12 Months Ended
Organization and Operations	Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Operations	1. Organization and Operations Talen is a leading independent power producer and energy infrastructure company dedicated to powering the future. We own and operate approximately 10.7 gigawatts of power infrastructure in the United States, including 2.2 gigawatts of nuclear power and a significant dispatchable generation fleet. We produce and sell electricity, capacity, and ancillary services into wholesale U.S. power markets, with our generation fleet principally located in the Mid-Atlantic and Montana. Talen is headquartered in Houston, Texas.

Property, Plant, and Equipment - Summary of Depreciation, Amortization, and Accretion Expense (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 173	$ 133	$ 225	$ 432
Amortization expense	4	1	16	12
Accretion expense	24	31	57	78
Other	(1)	0	0	(2)
Depreciation, amortization and accretion	$ 200	$ 165	$ 298	$ 520

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ 465	$ 143	$ 1,013	$ (1,293)
Other Comprehensive Income (Loss)
Available-for-sale securities unrealized gain (loss), net (Note 9)	6	2	(14)	(69)
Postretirement benefit actuarial (gain) loss, net (Note 15)	0	(38)	5	(15)
Postretirement benefit prior service (credits) costs, net (Note 15)	0	0	21	0
Income tax benefit (expense)	(2)	8	5	31
Gains (losses) arising during the period, net of tax	4	(28)	17	(53)
Available-for-sale securities unrealized (gain) loss, net (Note 9)	4	7	1	33
Qualifying derivatives unrealized (gain) loss, net	(1)	0	0	(2)
Postretirement benefit prior service (credits) costs, net (Note 15)	0	0	(1)	1
Postretirement benefit actuarial (gain) loss, net (Note 15)	2	0	0	27
Income tax benefit (expense)	(3)	(2)	(6)	(21)
Reclassifications from AOCI, net of tax	2	5	(6)	38
Other comprehensive income (loss)	6	(23)	11	(15)
Comprehensive Income (Loss)	471	120	1,024	(1,308)
Less: Comprehensive income (loss) attributable to noncontrolling interest	(14)	9	15	(4)
Comprehensive Income (Loss) Attributable to Stockholders (Successor) / Member (Predecessor)	$ 485	$ 111	$ 1,009	$ (1,304)

Nuclear Decommissioning Trust Funds (Tables)

12 Months Ended

Dec. 31, 2024

Investments, Debt and Equity Securities [Abstract]

Schedule of Unrealized Gain (Loss) on Nuclear Decommissioning Trust Funds


	Successor
	December 31, 2024								December 31, 2023
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value		Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Cash equivalents	$	3	$	—	$	—	$	3	$	9	$	—	$	—	$	9
Equity securities	509		651		55		1,105		491		575		53		1,013
Debt securities	615		3		7		611		570		10		1		579
Receivables (payables), net	5		—		—		5		(26)		—		—		(26)
NDT funds	$	1,132	$	654	$	62	$	1,724	$	1,044	$	585	$	54	$	1,575

Summary of Available-for-Sale Debt Securities with Unrealized Losses

The aggregate related fair value of available-for-sale debt securities with unrealized losses as of December 31, 2024 (Successor) were:


	Fair Value		Unrealized Losses
Corporate debt securities	$	71	$	(2)
Municipal debt securities	60		(1)
U.S. Government debt securities	226		(4)
Debt securities in unrealized loss position	$	357	$	(7)

Summary of Maturities for Available-for-sale Debt Securities

The contractual maturities for available-for-sale debt securities presented on the Consolidated Balance Sheets were:


	Successor
	December 31, 2024		December 31, 2023
Maturities within one year	$	82	$	105
Maturities within two to five years	220		194
Maturities thereafter	309		280
Debt securities, fair value	$	611	$	579

Summary of Maturities for Available-for-sale Debt Securities

The sales proceeds, gains, and losses for available-for-sale debt securities for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Sales proceeds of NDT funds investments (a)	$	2,132	$	1,259	$	839	$	2,081
Gross realized gains	12		5		7		10
Gross realized losses	(13)		(11)		(12)		(43)

__________________

(a)Sales proceeds are used to pay income taxes and trust management fees. Remaining proceeds are reinvested in the NDT.

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2024

Income Tax Disclosure [Abstract]

Schedule of Components of Income Tax (Expense) Benefit

The components of “Income tax benefit (expense)” for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Federal	$	(113)	$	3	$	(15)	$	(9)
State	(31)		1		(2)		(4)
Current income taxes	(144)		4		(17)		(13)
Federal	47		(55)		(184)		68
State	(1)		—		(11)		(21)
Deferred income taxes	46		(55)		(195)		47
Investment tax credit	—		—		—		1
Income tax benefit (expense)	$	(98)	$	(51)	$	(212)	$	35

Schedule of Effective Income Tax Rate Reconciliation

The reconciliations of the effective tax rate for the periods were:


	Successor						Predecessor
	Year Ended December 31, 2024			May 18 through December 31, 2023			January 1 through May 17, 2023			Year Ended December 31, 2022

Income (loss) before income taxes	$	1,111		$	194		$	677		$	(1,328)
Income tax benefit (expense)	(98)			(51)			(212)			35
Effective tax rate	8.8		%	26.3		%	31.3		%	2.6		%
Federal income tax statutory tax rate	21		%	21		%	21		%	21		%
Income tax benefit (expense) computed at the federal income tax statutory tax rate	$	(234)		$	(41)		$	(143)		$	279
Income tax increase (decrease) due to:
Change in valuation allowance	128			(43)			129			(198)
Nuclear PTC	46			—			—			—
Reorganization adjustments	23			26			(138)			—
Return to provision	11			—			—			—
Other permanent differences	3			22			(16)			(94)
Nuclear decommissioning trust taxes	(27)			(16)			(9)			28

State income taxes, net of federal benefit	(48)			1			(34)			19

Other	—			—			(1)			1
Income tax benefit (expense)	$	(98)		$	(51)		$	(212)		$	35

Schedule of Deferred Tax Assets and Liabilities

The components of deferred tax liabilities and deferred tax assets were:


	Successor
	December 31, 2024		December 31, 2023

Nuclear decommissioning trust	$	502	$	443
Property, plant and equipment, net	465		560
Unrealized gain on qualifying derivatives	32		12
Investment in subsidiaries	—		14

Deferred tax liabilities	999		1,029
Less:
Interest limitation carryforward	340		336
Federal net operating loss carryforwards	164		273
Accrued pension costs	80		78
Accrued liabilities	30		26
State net operating loss carryforwards	15		26


Other	8		10
Deferred tax assets	637		749
Valuation allowance	—		(128)
Deferred tax liabilities, net	$	362	$	408

Summary of Operating Loss Carryforwards

The components of NOL carryforwards were:


	Successor
	December 31, 2024		December 31, 2023
Federal, expirations 2036 - 2037	$	—	$	43
Federal, indefinite expiration, limited to annual utilization of 80%	783		1,258
State, expirations 2025 - 2043	310		555

Schedule of Inflation Reduction Act Credits

The credit would be:


Annual Gross Receipts						Credit Amount
$25 per MWh or less						$15 per MWh
Greater than $25 per MWh						Ratably reduced until gross receipts equal $43.75 per MWh, $0 after that threshold

Segments - Schedule of Adjusted EBITDA and Reconciling Items (Details) - USD ($) $ in Millions	5 Months Ended	7 Months Ended	12 Months Ended
	May 17, 2023	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2022
Adjusted EBITDA:
Adjusted EBITDA
Reconciling Items:
Interest expense and other finance charges	(163)	(176)	(238)	(359)
Income tax benefit (expense)	(212)	(51)	(98)	35
Depreciation, amortization and accretion	(200)	(165)	(298)	(520)
Nuclear fuel amortization	(33)	(108)	(123)	(94)
Total reorganization items from reorganization adjustments	799	0	0	(812)
Unrealized (gain) loss on commodity derivative contracts	(63)	52	62	625
Nuclear decommissioning trust funds gain (loss), net (Note 9)	57	108	178	(184)
Stock-based compensation expense	0	(19)	(33)	0
Long-term incentive compensation expense	0	(2)	(21)	0
Gain (loss) on asset sales, net	50	7	884	0
Non-cash impairments	(381)	(3)	(1)	0
Legal settlements and litigation costs	(1)	84	10	(20)
Unusual market events	(14)	19	1	(29)
Net periodic defined benefit cost	3	(2)	(14)	(12)
Operational and other restructuring activities	(17)	(48)	(76)	(570)
Hedge termination losses, net	0	0	0	(158)
Development expenses	(10)	(7)	(1)	(17)
Non-cash inventory net realizable value, obsolescence, and other charges	(56)	(4)	(20)	(3)
Consolidation of subsidiary gain (loss) (Note 2)	0	0	0	(170)
Noncontrolling interest	14	42	21	(3)
Other items	(3)	(10)	10	(17)
Net Income (Loss)	465	143	1,013	(1,293)
Operating Segments
Adjusted EBITDA:
Adjusted EBITDA	688	377	775	981
Corporate and Eliminations
Adjusted EBITDA:
Adjusted EBITDA
Reconciling Items:
Interest expense and other finance charges	(163)	(176)	(238)	(359)
Net Income (Loss)	(30)	(64)	(76)	(69)
PJM \| Operating Segments
Adjusted EBITDA:
Adjusted EBITDA	688	377	775	981
Reconciling Items:
Interest expense and other finance charges	0	0	0	0
Other \| Operating Segments
Adjusted EBITDA:
Adjusted EBITDA
Reconciling Items:
Interest expense and other finance charges	0	0	0	0
Net Income (Loss)	$ 37	$ 113	$ 71	$ 103

Commitments and Contingencies - Other Commitments and Contingencies (Details) $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($) lawsuit
Commitments and Contingencies Disclosure [Abstract]
Nuclear insurance, liability limit per accident	$ 16,300
Nuclear insurance, coverage	500
Nuclear insurance, maximum deferred premiums	332
Nuclear insurance, annual maximum deferred premiums	49
Maximum insurance converge, nuclear	2,000
Maximum insurance converge, non-nuclear	1,000
Retrospective premiums, maximum assessment	$ 48
Number Of lawsuits \| lawsuit	2

Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2024

Equity [Abstract]

Schedule of Share Repurchase Program

Summary of activity under the SRP and direct repurchases:


		Successor
	Year Ended December 31, 2024
		Number of Shares (a) (b)	Share Price (c)		Total Amount
Share repurchases		13,227,222	$	149.50	$	1,977
Share retirements		(13,227,222)	149.50		(1,977)

__________________

(b)Includes 5,275,862 shares repurchased as result of a tender offer in June 2024 at a weighted average price of $117.16 per share.

(c)Weighted average price per share, including transaction costs and excise taxes.

Schedule of Accumulated Other Comprehensive Income

Changes in AOCI for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Beginning balance	$	(23)	$	—	$	(167)	$	(152)
Gains (losses) arising during the period (a)	12		(36)		6		(84)
Reclassifications to Consolidated Statements of Operations (b)	—		7		5		59
Income tax benefit (expense)	(1)		6		(5)		10
Other comprehensive income (loss)	11		(23)		6		(15)
Cancellation of equity at Emergence	—		—		161		—
Accumulated other comprehensive income (loss)	$	(12)	$	(23)	$	—	$	(167)

__________________

(b)Primarily related to “Available-for-sale securities unrealized gain (loss), net” and “Postretirement benefit actuarial (gain) loss, net” for the year ended December 31, 2022 (Predecessor).

The components of AOCI, net of tax, were:


	Successor
	December 31, 2024		December 31, 2023
Available-for-sale securities unrealized gain (loss), net	$	(3)	$	5

Postretirement benefit prior service credits (costs), net	14		—
Postretirement benefit actuarial gain (loss), net	(23)		(28)
Accumulated other comprehensive income (loss)	$	(12)	$	(23)

The locations of pre-tax gains (losses) reclassified from AOCI and included on the Consolidated Statements of Operations for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Nuclear decommissioning trust funds gain (loss), net (a)	$	(1)	$	(7)	$	(4)	$	(33)
Depreciation, amortization and accretion (b)	—		—		1		2
Operation, maintenance and development (c)	1		—		—		(1)
Other non-operating income (expense), net (d)	—		—		(2)		(27)
Total	$	—	$	(7)	$	(5)	$	(59)

__________________

(a)Available-for-sale securities unrealized gain (loss), net.

(b)Qualifying derivatives unrealized gain (loss).

(c)Postretirement benefit prior service credits (costs), net.

(d)Postretirement benefit actuarial gain (loss), net.

Property, Plant, and Equipment - Reliability Impact Assessments (Details) - Subsequent Event	Jan. 01, 2025 USD ($)
Property, Plant, and Equipment, Brandon Shores
Property, Plant and Equipment [Line Items]
Fixed-cost monthly payments	$ 12,083,333
Fixed-cost per day payments	312
Monthly performance hold-back	416,667
Property, Plant, And Equipment, Wagner
Property, Plant and Equipment [Line Items]
Fixed-cost monthly payments	2,916,667
Fixed-cost per day payments	137
Monthly performance hold-back	$ 208,333

Risk Management, Derivative Instruments and Hedging Activities (Tables)

12 Months Ended

Dec. 31, 2024

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Net Notional Volumes of Open Commodity Derivatives and Interest Rate Derivatives

The net notional volumes of open commodity derivatives were:


	Successor
	December 31, 2024 (a)	December 31, 2023 (a)
Power (MWh)	(38,615,192)	(27,557,871)
Natural gas (MMBtu)	32,405,460	8,314,060
Emission allowances (tons)	100,000	500,000

__________________

(a)The volumes may be less than the contractual volumes, as the probability that option contracts will be exercised is considered in the volumes displayed.

Open interest rate derivatives are related to the TLB-1 indebtedness and mature in 2026. The net notional volumes of open interest rate derivatives were:


	Successor
	December 31, 2024		December 31, 2023
Interest rate (in millions)	$	290	$	290

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value

Balance Sheets Presentation. The fair value of derivative instruments presented within assets and liabilities on the Consolidated Balance Sheets were:


	Successor
	December 31, 2024				December 31, 2023
	Assets		Liabilities		Assets		Liabilities
Commodity contracts	$	65	$	—	$	88	$	32
Interest rate contracts	1		—		1		—

Total current derivative instruments	66		—		89		32
Commodity contracts	4		7		6		5
Interest rate contracts	1		—		—		6
Total non-current derivative instruments	$	5	$	7	$	6	$	11

Schedule of Effect of Netting, Offsetting Assets


	Gross Derivative Instruments		Eligible for Offset		Net Derivative Instruments		Collateral (Posted) Received		Net Amounts
December 31, 2024 (Successor)
Assets	$	227	$	(154)	$	73	$	(2)	$	71
Liabilities	173		(154)		19		(12)		7
December 31, 2023 (Successor)
Assets	$	295	$	(198)	$	97	$	(2)	$	95
Liabilities	300		(198)		102		(59)		43

Schedule of Effect of Netting, Offsetting Liabilities


	Gross Derivative Instruments		Eligible for Offset		Net Derivative Instruments		Collateral (Posted) Received		Net Amounts
December 31, 2024 (Successor)
Assets	$	227	$	(154)	$	73	$	(2)	$	71
Liabilities	173		(154)		19		(12)		7
December 31, 2023 (Successor)
Assets	$	295	$	(198)	$	97	$	(2)	$	95
Liabilities	300		(198)		102		(59)		43

Schedule of Derivative Instruments, Gain (Loss)

The location and pre-tax effect of “Derivative instruments” presented on the Consolidated Statements of Operations for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Realized gain (loss) on commodity contracts
Energy revenues (a)	$	317	$	360	$	644	$	(613)
Fuel and energy purchases (a)	(35)		(91)		(34)		127
Unrealized gain (loss) on commodity contracts
Operating revenues (b)	42		55		60		677
Energy expenses (b)	20		(3)		(123)		(52)
Realized and unrealized gain (loss) on interest rate contracts
Interest expense and other finance charges	9		(4)		—		30

__________________

(a)Does not include those derivative instruments that settle through physical delivery.

(b)Presented as “Unrealized gain (loss) on derivative instruments” on the Consolidated Statements of Operations.

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Nuclear decommissioning trust	$ 502	$ 443
Property, plant and equipment, net	465	560
Unrealized gain on qualifying derivatives	32	12
Investment in subsidiaries	0	14
Deferred tax liabilities	999	1,029
Less:
Interest limitation carryforward	340	336
Federal net operating loss carryforwards	164	273
Accrued pension costs	80	78
Accrued liabilities	30	26
State net operating loss carryforwards	15	26
Other	8	10
Deferred tax assets	637	749
Valuation allowance	0	(128)
Deferred tax liabilities, net	$ 362	$ 408

Asset Retirement Obligations and Accrued Environmental Costs - Summary of Asset Retirement Obligations and Accrued Environmental Costs (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023	Dec. 31, 2022
Asset Retirement Obligation Disclosure [Abstract]
Asset retirement obligations	$ 498	$ 464	$ 766	$ 751
Accrued environmental costs	21	23
Total asset retirement obligations and accrued environmental costs	519	487
Less: asset retirement obligations and accrued environmental costs due within one year	51	18
Asset retirement obligations and accrued environmental costs due after one year	$ 468	$ 469	$ 442
Environmental Loss Contingency, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Asset retirement obligations and accrued environmental costs due after one year	Asset retirement obligations and accrued environmental costs due after one year
Environmental Loss Contingency, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities	Other current liabilities

Revenue (Tables)

12 Months Ended

Dec. 31, 2024

Revenue from Contract with Customer [Abstract]

Summary of Components of Operating Revenues

The components of operating revenues for the periods were:


	Successor				Predecessor
	Year Ended December 31, 2024		May 18 through December 31, 2023		January 1 through May 17, 2023		Year Ended December 31, 2022
Capacity revenues	$	192	$	133	$	108	$	377
Electricity sales and ancillary services, ISO/RTO	1,144		880		281		2,534
Physical electricity sales, bilateral contracts, other	147		71		62		298
Other revenue from customers	91		81		27		—
Total revenue from contracts with customers	1,574		1,165		478		3,209
Realized and unrealized gain (loss) on derivative instruments	307		179		732		(120)
Nuclear PTC (a)	220		—		—		—
Other revenue	14		—		—		—
Operating revenues	$	2,115	$	1,344	$	1,210	$	3,089

__________________

Summary of Accounts Receivable

“Accounts receivable” presented on the Consolidated Balance Sheets were:


	Successor
	December 31, 2024		December 31, 2023
Customer accounts receivable	$	66	$	52
Other accounts receivable	57		85
Accounts receivable	$	123	$	137

Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction

As of December 31, 2024 (Successor), the expected future period capacity revenues subject to unsatisfied or partially unsatisfied performance obligations were:


	2025		2026 (a)		2027		2028		2029
Expected capacity revenues	$	478	$	281	$	3	$	1	$	—

__________________

(a)Estimated through May 31, 2026. The PJM BRA for the 2026/2027 PJM Capacity Year has been delayed to July 2025.

Organization and Operations (Details)	Dec. 31, 2024 GW
Property, Plant and Equipment [Line Items]
Generation capacity	10,700
Nuclear fuel
Property, Plant and Equipment [Line Items]
Generation capacity	2,200

Postretirement Benefit Obligations - Fair Value Hierarchy (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	May 17, 2023	Dec. 31, 2022
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	$ 911	$ 975	$ 997	$ 994
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	71	75	$ 74	$ 75
Level 1 \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	(15)	52
Level 1 \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	7	8
Level 2 \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	18	16
NAV \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	891	949
NAV \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	46	50
Total trust funds \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	911	976
Total trust funds \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	71	74
Total trust funds \| Level 1 \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	(15)	52
Total trust funds \| Level 1 \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	7	8
Total trust funds \| Level 2 \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	18	16
Total trust funds \| NAV \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	891	949
Total trust funds \| NAV \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	46	50
Cash equivalents \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	100	169
Cash equivalents \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	4	7
Cash equivalents \| Level 1 \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Cash equivalents \| Level 1 \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Cash equivalents \| Level 2 \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Cash equivalents \| NAV \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	100	169
Cash equivalents \| NAV \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	4	7
Commingled equity securities \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	274	288
Commingled equity securities \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	10	9
Commingled equity securities \| Level 1 \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Commingled equity securities \| Level 1 \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Commingled equity securities \| Level 2 \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Commingled equity securities \| NAV \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	274	288
Commingled equity securities \| NAV \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	10	9
Commingled debt securities \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	286	301
Commingled debt securities \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	32	34
Commingled debt securities \| Level 1 \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Commingled debt securities \| NAV \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	286	301
Commingled debt securities \| NAV \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	32	34
Alternative and other investments \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	216	243
Alternative and other investments \| Level 1 \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	(15)	52
Alternative and other investments \| NAV \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	231	191
U.S. Government debt securities \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	7	8
U.S. Government debt securities \| Level 1 \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	7	8
U.S. Government debt securities \| Level 2 \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
U.S. Government debt securities \| NAV \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Corporate debt securities \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	18	16
Corporate debt securities \| Level 1 \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Corporate debt securities \| Level 2 \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	18	16
Corporate debt securities \| NAV \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	0
Receivables (payables), net \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	35	(25)
Restricted 401(h) assets \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	0	(1)
Restricted 401(h) assets \| Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan assets	$ 0	$ 1