Second Quarter 2004 Financial Results August 5, 2004

Safe Harbor StatementThis Investor Presentation contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Forward-looking statements are subject to certain risks, uncertainties and assumptions and typically can be identified by the use of words such as expect, estimate, anticipate, forecast, plan, believe and similar terms. Such forward-looking statements include, but are not limited to, expected earnings, future growth and financial performance, the successful closing of announced transactions, the successful closing of the coal transportation agreement, the successful implementation of our acquisition and repowering strategy, the outcome of hearings on our RMR agreements and cost tracker for scheduled expenses. Although NRG believes that its expectations are reasonable, it can give no assurance that these expectations will prove to have been correct, and actual results may vary materially. Factors that could cause actual results to differ materially from those contemplated above include, among others, general economic conditions, hazards customary in the power industry, competition in wholesale power markets, the volatility of energy and fuel prices, failure of customers to perform under contracts, changes in the wholesale power markets and related government regulation, the condition of capital markets generally, our ability to access capital markets, unanticipated outages at generation facilities, out ability to convert facilities to western coal, our substantial indebtedness and the possibility that we may incur additional indebtedness, adverse results in current and future litigation, delays in or failure to meet closing conditions in announced transactions, failure to identify or successfully implement acquisitions and repowerings, the amount of proceeds from asset sales and adverse rulings on our RMR agreements and cost tracker for scheduled expenses, resulting in us refunding certain payments received to date.

NRG undertakes no obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise. The adjusted EBITDA guidance is an estimate as of todays date, August 5, 2004 and is based on assumptions believed to be reasonable as of this date. NRG disclaims any current intention to update such guidance. The foregoing review of factors that could cause NRGs actual results to differ materially from those contemplated in the forward-looking statements included in this Investor Presentation should be considered in connection with information regarding risks and uncertainties that may affect NRG's future results included in NRG's filings with the Securities and Exchange Commission at www.sec.gov.

AgendaOperational UpdateQ2 Financial Results and OutlookQ&A

Financial HighlightsSecond quarter performanceAdjusted EBITDA of $232 million Reported net income of $83 million

YTD performanceAdjusted EBITDA of $489 millionReported net income of $113 millionFree cash flow of $355 million

Operating HighlightsThe Company exhibited continued strength in all phases of operating performance:Safety20% lower injury frequency rate than industry average with continuing improvementPlant availability96% in-market availability through May 2004EnvironmentalMet and exceeded environmental standards for compliance with air, waste, and water regulationsSummer Maintenance at 12 plants preparedness completed ontime and within budget

Asset Sales - 2004 We continue to make progress rationalizing nonsupported assets for value:

Connecticut Update

MWRevenue

New RMR 1,392$5.10/kW-moMiddletownMontvilleDevon 11-14Devon 7 RMR 107$6.09/kW-mo(through May)$10.15/kW-mo(June-September)Norwalk/CT Jets 462Market prices through PUSH bidding8

California UpdateCPUC interim procurement order directed at California utilitiesAging power plant study to be released, expected to have a positive impactContinued dialogue with California utilities regarding 2005 and beyond

Financial Results

Key Financial HighlightsOperating revenues574 1,174Gross margin349683Net income 83113EBITDA282529Adjusted EBITDA233489$ millionsYTDQ2

2nd Quarter 2004 Spark Spreads Dark Gas Dual Fuel/Oil Spread1,2 Spread Spread

North America:Gross Margin (000s) $71,220 $2,027 $7,351Spark Spread $/MWh $25.03 $7.94 $43.61

1 Dark spread is the spread between energy prices and coal-fired generation costs2 Does not include LaGen contracted output

NRG Generation by Fuel2nd Quarter North American Generation by Fuel Type Versus Net North American Capacity Owned

EBITDA by Operating Segment - YTD($ millions) Q2 Q2 Q2 Adj Q1 Adj YTD Adj EBITDA Adj EBITDA EBITDA EBITDANortheast 79.2 .3 79.5 114.8 194.3South Central 30.3 1.6 31.9 29.7 61.6West Coast 54.9 -- 54.9 33.4 88.3Other NA 23.2 (2.6) 20.6 12.3 32.9 International 48.2 (12.9) 35.2 54.2 89.4Alt. Energy & Services 54.4 (38.9) 15.5 17.0 32.5 Corp Unallocated (8.6) 3.5 (5.1) (4.5) (9.6)Total 281.6 (49.0)232.6 256.9 489.4

Cash Flow YTD

Liquidity06/30/0403/31/04Unrestricted Cash:Domestic 676665International 145169Restricted Cash:Domestic 9790International 5552Total Cash 973976

Letter of Credit Availability 118137Revolver Availability 250250

Total Current Liquidity $1,341$1,363$ millions

2004 EBITDA and FCF Outlook

2004 Forecast Sensitivity Analysis ($4.7) million100 bpsInterest rates$35.7 million$1.00/mmbtuNatural Gas--$1.00/tonCoal--$1.00/bblOilResults in the following change to 2004 pre-tax income:Factor Increased by:FactorsSensitivities are for the remaining 6 months of 2004, assuming current hedged positions

Enterprise Value1) Includes expected asset salesHow we look at equity value:

ConclusionContinued focus on operating performanceContinued focus on rationalizing our businessesContinued focus on maintaining strong leverage ratios

Supplemental information

Adjusted Net Income ReconciliationNRG ENERGY, INC. AND SUBSIDIARIESReconciliation of NonGAAP Financial MeasuresAdjusted Net Income Reconciliation

Adjusted EBITDA ReconciliationNRG ENERGY, INC. AND SUBSIDIARIESReconciliation of NonGAAP Financial MeasuresAdjusted EBITDA Reconciliation

GAAP Reconciliation (cont.)EBITDA, Adjusted EBITDA and adjusted net income are non-GAAP financial measures. These measurements are not recognized in accordance with GAAP and should not be viewed as an alternative to GAAP measures of performance. The presentation of Adjusted EBITDA and adjusted net income should not be construed as an inference that NRGs future results will be unaffected by unusual or nonrecurring items.EBITDA represents net income before interest, taxes, depreciation and amortization. EBITDA is presented because NRG considers it an important supplemental measure of its performance and believe debt-holders frequently use EBITDA to analyze operating performance and debt service capacity. EBITDA has limitations as an analytical tool, and you should not consider it in isolation, or as a substitute for analysis of our operating results as reported under GAAP. Some of these limitations are: EBITDA does not reflect cash expenditures, or future requirements for capital expenditures, or contractual commitments; EBITDA does not reflect changes in, or cash requirements for, working capital needs; EBITDA does not reflect the significant interest expense, or the cash requirements necessary to service interest or principal payments, on debts; Although depreciation and amortization are noncash charges, the assets being depreciated and amortized will often have to be replaced in the future, and EBITDA does not reflect any cash requirements for such replacements; and Other companies in this industry may calculate EBITDA differently than NRG does, limiting its usefulness as a comparative measure.Because of these limitations, EBITDA should not be considered as a measure of discretionary cash available to use to invest in the growth of NRGs business. NRG compensates for these limitations by relying primarily on our GAAP results and using EBITDA and Adjusted EBITDA only supplementally. See the statements of cash flow included in the financial statements that are a part of this press release.Adjusted EBITDA is presented as a further supplemental measure of operating performance. Adjusted EBITDA represents EBITDA adjusted for reorganization, restructuring, impairment and corporate relocation charges, discontinued operations, and write downs and losses on the sales of equity method investments; factors which we do not consider indicative of future operating performance. The reader is encouraged to evaluate each adjustment and the reasons NRG considers it appropriate for supplemental analysis. As an analytical tool, Adjusted EBITDA is subject to all of the limitations applicable to EBITDA. In addition, in evaluating Adjusted EBITDA, the reader should be aware that in the future NRG may incur expenses similar to the adjustments in this presentation.

Significant Q1 Variances Budget to Actual:Gross Margin:-Merchant revenue increase due to an extended winter which drove demand up especially at LaGen and NYW.-Accounting change subtracting $17.3MM from Major Maintenance and routing it to CAPEX.