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UNAUDITED PRO FORMA COMBINED FINANCIAL INFORMATION

The following unaudited pro forma combined financial information is presented by NRG Energy, Inc. (“NRG” or the “Company”) to illustrate the estimated effects of the acquisition of a portfolio of natural gas-fired and dual fuel facilities, and CPower, a leading demand response platform, from LS Power (the “LS Power Portfolio”), (“the Acquisition”), and certain other related transactions and adjustments described below (collectively, the “Transactions Accounting Adjustments”).

Acquisition of LS Power Portfolio

On January 30, 2026, NRG completed the acquisition of the LS Power Portfolio, pursuant to the Purchase and Sale Agreement (the “Purchase Agreement”) dated as of May 12, 2025 by and among the Company, NRG East Generation Holdings LLC, NRG Texas LLC, NRG Demand Response Holdings LLC, NRG Gas Development Company, LLC (all of which are subsidiaries of the Company) and Lightning Power Holdings, LLC, Thunder Generation, LLC, CCS Power Holdings, LLC and Linebacker Power Development Funding, LLC (all of which were affiliates of LS Power Equity Advisors, LLC). Pursuant to the Purchase Agreement, NRG acquired all of the issued and outstanding equity interests of Lightning Power, LLC (“Lightning”)¹, Linebacker Power Holdings, LLC (“Linebacker”)², CCS Intermediate HoldCo, LLC (“CCS”)³ and Jack County Power Development, LLC (“JCPD”)⁴. The LS Power Portfolio includes 18 natural gas-fired and dual fuel facilities totaling approximately 13 GW of capacity, located across nine states, as well as CPower, a leading demand response platform, which operates in all the country’s deregulated energy markets and has more than 2,000 commercial and industrial customers.

Subject to the terms and conditions of the Purchase Agreement, the purchase price for the transaction consists of 24,250,000 shares of common stock of the Company, par value of $0.01 per share (the “Stock Consideration”), and $6.4 billion plus preliminary working capital and certain other adjustments of $0.5 billion in cash (the “Cash Consideration”). As part of the transaction, NRG also assumed approximately $3.2 billion of debt.

In connection with the Purchase Agreement, NRG entered into a commitment letter for a 364-day Senior Secured Bridge Facility (the “Bridge Facility”) in a principal amount not to exceed $4.4 billion for the purposes of paying a portion of the Cash Consideration for the acquisition and paying fees and expenses in connection with the acquisition. The Bridge Facility was terminated on October 8, 2025, subsequent to obtaining permanent financing.

Pro Forma Financial Information

The unaudited pro forma combined balance sheet as of December 31, 2025 combines the historical consolidated balance sheet of NRG and the historical balance sheets of the LS Power acquired entities (as listed below) after giving effect to the acquisition of the LS Power Portfolio and the related transactions, as if they had occurred on December 31, 2025. The unaudited pro forma combined statement of operations for the year ended December 31, 2025 combines the historical consolidated statement of operations of NRG and the historical statements of operations of the LS Power acquired entities (as listed below), after giving effect to the Transactions Accounting Adjustments, as if they had occurred on January 1, 2025. We refer to these unaudited pro forma combined balance sheet and unaudited pro forma combined statement of operations as the “pro forma financial information”.

¹ The pro forma financial information for Lightning was prepared using the financial statements of Lightning Power, LLC for the year ended December 31, 2025 and for the period August 9, 2024 to December 31, 2024. The period from January 1, 2024 to August 8, 2024 is included in the financial statements of Fund III Projects (as defined below) and Gridiron Intermediate Holdings, LLC (“Gridiron”). The “Fund III Projects” are comprised of the operations and assets held by Granite Generation, LLC, Helix Gen Funding, LLC, Ocean State Power LLC, and Rise Light & Power, LLC.

² Linebacker Power Holdings, LLC (one of the acquired entities) owns Linebacker Power Funding, LLC. The pro forma financial information was prepared using the available audited and unaudited financial statements of Linebacker Power Funding, LLC. Differences between the two entities include affiliate billings and certain incremental general and administrative costs and are immaterial to the pro forma information.

³ CCS Intermediate Holdco, LLC (one of the acquired entities) owns CCS Power Finance Co, LLC (“CPower”). The pro forma financial information was prepared using the available audited and unaudited financial statements of CPower. Differences between the two entities include immaterial affiliate billings and certain immaterial incremental general and administrative costs. Removal of intercompany note of $16.5 million between the two entities and its related impact on the pro forma information is included in the pro forma Transactions Accounting Adjustments.

⁴ The pro forma financial information does not include the estimated effects from the acquisition of Jack County Power Development, LLC, as audited and unaudited financial statements for that entity are not available and the effects of that entity are immaterial to the pro forma information.

The pro forma financial information has been prepared by NRG for illustrative and informational purposes only, in accordance with Regulation S-X Article 11, Pro Forma Financial Information. The pro forma financial information is based on the Transactions Accounting Adjustments and assumptions and is not necessarily indicative of what NRG’s consolidated statement of operations or consolidated balance sheet actually would have been had the Transactions Accounting Adjustments been completed as of the dates indicated, or what they will be for any future periods. The pro forma financial information does not purport to project the future financial position or operating results of NRG following the completion of the Acquisition and the related transactions. The pro forma financial information does not reflect any revenue enhancements, cost savings, operating synergies or restructuring costs that may be achievable or incurred prospectively in connection with the Acquisition and the related transactions.

The pro forma financial information for the acquisition of the LS Power Portfolio has been prepared using the acquisition method of accounting under U.S. Generally Accepted Accounting Principles (“U.S. GAAP”) with NRG being the accounting acquirer in the acquisition. The purchase price will be allocated to the assets acquired and liabilities assumed based upon their estimated fair values as of the acquisition date, and any excess value of the consideration transferred over the net assets will be recognized as goodwill. The Company has made a preliminary allocation of the purchase price to the assets acquired and liabilities assumed as of the assumed acquisition date based on NRG’s preliminary valuation of the tangible and intangible assets acquired and liabilities assumed using information currently available. Differences between these preliminary estimates, which were made solely for the purpose of this pro forma financial information, and the final acquisition accounting will occur and these differences could have a material impact on the accompanying pro forma financial information.

The purchase price for the acquisition of the LS Power Portfolio consists of Cash Consideration of $6.4 billion plus preliminary working capital and certain other adjustments of $0.5 billion, and Stock Consideration of 24,250,000 shares of common stock of the Company, par value of $0.01 per share.

The pro forma financial information gives effect to the following sources of funds to satisfy the Cash Consideration:

The pro forma financial information should be read in conjunction with the accompanying explanatory notes. In addition, the pro forma financial information is derived from and should be read in conjunction with the following historical financial statements and the related notes of NRG and the LS Power acquired entities as listed below:

NRG Financial Statements:

LS Power Acquired Entities’ Financial Statements:

NRG ENERGY, INC. AND SUBSIDIARIES

UNAUDITED PRO FORMA COMBINED BALANCE SHEET

AS OF DECEMBER 31, 2025

NRG ENERGY, INC. AND SUBSIDIARIES

UNAUDITED PRO FORMA COMBINED BALANCE SHEET

AS OF DECEMBER 31, 2025 (Continued)

NRG ENERGY, INC. AND SUBSIDIARIES

UNAUDITED PRO FORMA COMBINED STATEMENT OF OPERATIONS

FOR THE YEAR ENDED DECEMBER 31, 2025

NOTES TO UNAUDITED PRO FORMA COMBINED FINANCIAL INFORMATION

Note 1. Basis of Pro Forma Presentation

The pro forma financial information for the Acquisition has been prepared using the acquisition method of accounting under U.S. GAAP, in accordance with ASC 805, and is derived from the audited and unaudited historical financial statements of NRG and the acquired entities.

The unaudited pro forma combined balance sheet as of December 31, 2025 combines the historical consolidated balance sheet of NRG and the historical balance sheets of the LS Power acquired entities (as listed above) after giving effect to the acquisition of the LS Power Portfolio and the related transactions, as if they had occurred on December 31, 2025. The unaudited pro forma combined statement of operations for the year ended December 31, 2025 combines the historical consolidated statement of operations of NRG and the historical statements of operations of the LS Power acquired entities (as listed above), after giving effect to the Transactions Accounting Adjustments, as if they had occurred on January 1, 2025.

The pro forma financial information has been prepared by NRG for illustrative and informational purposes only in accordance of Article 11. The pro forma financial information is based on the Transactions Accounting Adjustments and assumptions and is not necessarily indicative of what NRG’s consolidated statement of operations or consolidated balance sheet actually would have been had the Transactions Accounting Adjustments been completed as of the dates indicated, or what they will be for any future periods. The pro forma financial information does not purport to project the future financial position or operating results of NRG following the completion of the Acquisition. The pro forma financial information does not reflect any revenue enhancements, cost savings, operating synergies or restructuring costs that may be achievable or incurred prospectively in connection with the Acquisition and related transactions.

The acquisition method of accounting requires an acquirer to recognize and measure in its financial statements the identifiable assets acquired and the liabilities assumed at fair value at the acquisition date. The determination of fair value used in the Transactions Accounting Adjustments is preliminary and based on management’s best estimates considering currently available information and certain assumptions that management believes are reasonable under the circumstances. The purchase price allocation presented is dependent upon certain valuations and other analyses that have not yet been finalized. The actual amounts eventually recorded for purchase accounting, including the identifiable intangibles and goodwill may differ materially from the information presented and could be materially impacted by changing fair value measurements caused by the volatility in the current market environment.

Under ASC 805, acquisition-related transactions costs are not included as a component of the consideration transferred and are expensed in the period in which the costs are incurred. Total costs related to the Acquisition are estimated to be $81 million, of which $32 million were recorded in the historical Consolidated Statement of Operations of NRG for the year ended December 31, 2025 and estimated costs of $49 million were accrued in the pro forma combined financial statements. Acquisition costs include primarily due diligence, valuation, legal and filing fees, professional and other consulting fees.

During the preparation of the unaudited pro forma combined financial information, management performed a preliminary analysis of the acquired entities financial information to identify differences in accounting policies as compared to those of NRG. Except as noted below, at this time NRG is not aware of any material differences in the accounting policies followed by NRG and those used by the acquired entities in preparing its consolidated financial statements that would have a material impact on the pro forma financial information.

During the preparation of the unaudited pro forma combined financial information, management identified that LS Power acquired entities elected to expense all maintenance costs to costs of operations in the period incurred, which is different than NRG’s policy to capitalize a portion of maintenance costs that extend the life of an asset and depreciate over the expected period of benefit. The Company recorded pro forma adjustments aiming to align the recognition of the major maintenance costs of the LS Power entities based on information currently available (see Note 8(a,b)). When additional information is available and additional analysis is performed, the Company may adjust such amounts and may identify other policy differences.

Note 2. Preliminary Purchase Price and Related Financing

The purchase price for the acquisition of the LS Power Portfolio consists of Stock Consideration of 24,250,000 shares of common stock of the Company, par value of $0.01 per share, and Cash Consideration of $6.4 billion plus preliminary working capital and certain other adjustments of $0.5 billion.

The pro forma financial information gives effect to the following sources of funds to satisfy the Cash Consideration:

Note 3. Reclassification Adjustments — Lightning

During the preparation of the unaudited pro forma combined financial statements, management performed a preliminary analysis of the Lightning financial information to identify differences in Lightning financial statement presentation as compared to the presentation of NRG. The below reclassification adjustments represent NRG’s best estimates based upon the information currently available to NRG. The reclassification adjustments are subject to change once more detailed information is available and additional analysis is performed.

Balance Sheet Reclassifications

Lightning

Audited Consolidated Balance Sheet

As of December 31, 2025

(a) Reclassification from Deposits and Other current assets to Prepayments and other current assets

(b) Reclassification from Accounts payable and accrued expenses to Accrued expenses and other current liabilities

(c) Reclassification from Asset retirement obligations to Other non-current liabilities

Statement of Operations Reclassifications

Lightning

Audited Consolidated Statement of Operations

For the Year Ended December 31, 2025

(a) Reclassification from Loss of risk management activities, Operating and maintenance, and Accretion to Cost of operations

(b) Reclassification of interest income from Interest expense, net to Other income, net

Note 4. Reclassification Adjustments — Linebacker

During the preparation of the unaudited pro forma combined financial statements, management performed a preliminary analysis of the Linebacker financial information to identify differences in Linebacker’s financial statement presentation as compared to the presentation of NRG. The below reclassification adjustments represent NRG’s best estimates based upon the information currently available to NRG. The reclassification adjustments are subject to change once more detailed information is available and additional analysis is performed.

Balance Sheet Reclassifications

Linebacker

Audited Consolidated Balance Sheet

As of December 31, 2025

(a) Reclassification from Other current assets to Prepayments and other current assets

(b) Reclassification from Accounts payable and accrued expenses to Accrued expenses and other current liabilities

Statement of Operations Reclassifications

Linebacker

Audited Condensed Consolidated Statement of Operations

For the Year Ended December 31, 2025

(a) Reclassification from Loss on risk management activities and Operating and maintenance to Cost of operations

(b) Reclassification of interest income from Interest expense, net to Other income, net

Note 5. Reclassification Adjustments — CPower

During the preparation of the unaudited pro forma combined financial statements, management performed a preliminary analysis of the CPower financial information to identify differences in CPower’s financial statement presentation as compared to the presentation of NRG. The below reclassification adjustments represent NRG’s best estimates based upon the information currently available to NRG. The reclassification adjustments are subject to change once more detailed information is available and additional analysis is performed.

Balance Sheet Reclassifications

CPower

Audited Consolidated Balance Sheet

As of December 31, 2025

(a) Reclassification from Unbilled accounts receivable to Accounts receivable, net

(b) Reclassification from Accrued payroll, benefits, and other and Other current liabilities to Accrued expenses and other current liabilities

Statement of Operations Reclassifications

CPower

Audited Consolidated Statement of Operations

For the Year Ended December 31, 2025

(a) Reclassification from Compensation to Selling, general and administrative costs

Note 6. Preliminary Calculation of Estimated Consideration and Preliminary Purchase Price Allocation

Estimated Consideration

The Company completed the acquisition of the LS Power Portfolio on January 30, 2026. The below is reflected in the Acquisition Accounting Adjustments in the unaudited pro forma combined balance sheet as of December 31, 2025.

The total consideration was calculated as follows:

Preliminary Purchase Price Allocation

Under the acquisition method of accounting, the identifiable assets acquired and liabilities assumed are recorded at fair value on the acquisition date. The Acquisition Accounting Adjustments included herein are preliminary and based on estimates of the fair value and useful lives of the assets acquired and liabilities assumed and have been prepared to illustrate the estimated effect of the acquisition.

The table below represents an initial allocation of the consideration to tangible and intangible assets to be acquired and liabilities to be assumed based on preliminary estimated fair values as of December 31, 2025:

The preliminary fair value of the identifiable intangible assets of $340 million, which includes customer relationships, technology related assets, trade names and contracts, will be amortized over the estimated useful life. The estimated weighted average useful life is approximately 12 years. The preliminary useful lives of the intangible assets were determined based on the expected pattern of the economic benefit. The expected amortization for the five years following the Acquisition is currently estimated to be $37 million per year. Goodwill represents the excess of the preliminary consideration over the estimated fair value of the underlying net assets acquired. Goodwill will not be amortized but instead will be reviewed for impairments at least annually, absent any indicators for impairment. Goodwill is attributable to the planned growth and synergies expected to be achieved from combining the operation of LS Power acquired entities with NRG’s existing business. The goodwill recorded is expected to be deductible for tax purposes.

The final purchase price allocation depends on certain valuations and other studies that have not yet been completed. The final determination of the purchase price allocation will be based on the net assets acquired as of the acquisition date and will depend on a number of factors, which cannot be predicted with any certainty at this time. The purchase price allocation may change materially based on receipt of more detailed information. Accordingly, the pro forma purchase price allocation is preliminary and is subject to further adjustments as additional information becomes available and as additional analyses and final valuations are completed. There can be no assurance that these additional analyses and final valuations will not result in significant changes to the estimates of fair value set forth above.

Note 7. Adjustments to Unaudited Pro Forma Combined Balance Sheet

The Transactions Accounting Adjustments reflected in the unaudited pro forma combined balance sheet are detailed below:

(a) Reflects draw from the Company’s Revolver Credit Facility on January 2026, and cash outflow to complete the acquisition of the LS Power Portfolio as detailed below:

(b) Reflects the elimination of $52 million of accounts receivable and $52 million of accounts payable, representing receivables and payables between NRG and LS Power acquired entities.

(c) Reflects the removal of historical goodwill of LS Power acquired entities of $255 million and recognition of preliminary goodwill of $1,856 million representing the excess of preliminary purchase price over the estimated fair value of the acquired assets and liabilities, identifiable intangible assets and related deferred income taxes.

(d) Reflects the removal of historical intangible assets of LS Power acquired entities of $131 million and recognition of preliminary estimated identifiable intangible assets of $340 million.

(e) The table below reflects the Transactions Accounting Adjustments to Current portion of long-term debt and finance leases and Long-term debt and finance leases:

(f) Reflects the accrual of $49 million of expected acquisition costs that are not yet recorded in NRG balance sheet as of December 31, 2025.

(g) Reflects $3 million of long-term deferred tax liabilities recorded as a result of the acquisitions accounting.

(h) Reflects elimination of the intercompany note payable and related accrued interest included in the CCS Power Finance Co, LLC historical balances payable to CCS Intermediate Holdco, LLC.

(i) Adjustment to reflect the issuance of 24,250,000 common shares of NRG, par value of $0.01 per share, based on NRG closing share price of $153.72 on January 29, 2026 as part of the Stock Consideration.

(j) Adjustments to Retained earnings include:

(k) Reflects the removal of LS Power acquired entities historical Member’s equity.

Note 8. Adjustments to Unaudited Pro Forma Statements of Operations

The Transactions Accounting Adjustments reflected in the unaudited pro forma combined statement of operations are detailed below:

(a) Adjustments to Revenue, Cost of operations and Selling, general and administrative costs include:

(b) Adjustments to Depreciation and amortization expense include:

(c) Reflects $49 million of expected acquisition costs recorded in the unaudited pro forma combined statement of operations for the year ended December 31, 2025, in addition to the $32 million that are already included in NRG’s historical consolidated statement of operations.

(d) Adjustments to Interest expense include:

(e) Reflects income tax effect of the Transactions Accounting Adjustments based on a combined estimated tax rate of 24.59% for all periods presented.

(f) Reflects the impact of the issuance of 24,250,000 Common Stock of NRG for the stock consideration portion of the LS Power Portfolio acquisition, on the calculation of the pro forma combined basic and diluted income per share. As the acquisition is being reflected as if it had occurred on January 1, 2025, the calculation of weighted average shares outstanding for basic and diluted pro forma combined income per share assumes the shares issued in connection with the acquisition have been outstanding for the entire year.