Exhibit 99.1

Leading the Way in Electricity SM

Business Update

May-June 2008

May 9, 2008

EDISON INTERNATIONAL®

Forward-Looking Statements

Leading the Way in Electricity SM

Statements contained in this presentation about future performance, including, without limitation, earnings, asset and rate base growth, load growth, capital investments, and other statements that are not purely historical, are forward-looking statements. These forward-looking statements reflect our current expectations; however, such statements involve risks and uncertainties. Actual results could differ materially from current expectations.

Important factors that could cause different results are discussed under the headings “Risk Factors” and “Management’s Discussion and Analysis” in Edison International’s 2007 Form 10-K and other reports filed with the Securities and Exchange Commission are available on our website: www.edisoninvestor.com. These forward-looking statements represent our expectations only as of the date of this presentation, and Edison International assumes no duty to update them to reflect new information, events or circumstances.

1

May 9, 2008

EDISON INTERNATIONAL®

What’s New Since Our April Update

Leading the Way in Electricity SM

Updated Information

1Q 2008 results and forward looking forecasts as appropriate

Regulatory matters (p. 19, 33)

Additional Topics

Renewable transmission planning (p. 20)

Electronic technology solutions to meet the climate change challenge (p. 21)

Shareholder value proposition (p. 31)

2

May 9, 2008

EDISON INTERNATIONAL®

Strategic Overview

Leading the Way in Electricity SM

May 9, 2008 3 EDISON INTERNATIONAL®

Edison International Value Drivers

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EIX Integrated Platform

SCE Value Drivers

Strong focus on infrastructure investment helps ensure reliability Tight system reserve margins keep focus on power procurement Energy Efficiency programs represent a new earnings opportunity Proposed $19.9 billion, 5-year capital investment plan1

?49%—Expand and strengthen distribution system

?28%—New transmission for renewable interconnection and system reliability

?13%—San Onofre steam generators and other generation

?6%—Edison SmartConnectTM metering program

?4%—Solar rooftop program Strengthened regulatory framework

?Three-year forward rate-setting

?Cost of capital

?Procurement cost recovery mechanisms

?FERC transmission incentives Financial performance

?Earning assets expected to grow 12%+ annually from 2007—2012

EMG Value Drivers

Low-cost coal generation portfolio

?Adjusted EBITDA has exceeded $1 billion annually2 Favorable capacity market trends Operational and marketing/trading capabilities

?Improving merchant price trends

?Experienced and value-adding trading capability Long-term environmental plan for Midwest Generation Financial flexibility & allocation of cash

?Hedging collateral

Diversify and grow generation portfolio

?Emphasize renewables, natural gas, clean-coal technologies

?Focus on organic growth

1 Subject to timely receipt of permitting, licensing and regulatory approvals. See “SCE Capital Investment” (page 12) for further information.

2 See use of Non-GAAP Financial Measures in Appendix for additional information on EBITDA and Adjusted EBITDA.

May 9, 2008 4 EDISON INTERNATIONAL®

Our Business Portfolio

Leading the Way in Electricity SM

Financial data is for the year ended December 31, 2007

Edison International

Revenue $13.1

Operating Cash Flow $3.2

Generation Capacity (MW) 14, 955

Market Capitalization $ 17.1

Southern California Edison

Revenue $10.5

Generation Capacity (MW) 5,502

Population Served (MM) 13+

Edison Mission Group Revenue $2.6

Generation Capacity (MW) 9,453

Wind Pipeline (MW) ~5,000

Note: Capacity and wind pipeline data is as of March 31, 2008, and market capitalization is as of May 1, 2008. Dollar amounts in billions, population served in millions. Edison Mission Group includes Edison Mission Energy and Edison Capital.

May 9, 2008 5 EDISON INTERNATIONAL®

Financial Strategies

Leading the Way in Electricity SM

Funding Growth Investments

Southern California Edison

??Operating cash flow and financing Edison Mission Energy

??Cash on hand, operating cash flow and project debt

Credit

Objectives1

Southern California Edison

??A rating metrics (current: S&P BBB, Fitch A, Moody’s A3) Edison Mission Energy

??BB rating metrics (current: S&P & Fitch BB-, Moody’s B1)

Dividend

Policy

Targeting annual dividend increases

Dividend increases balanced with growth investments Parent financing capacity supports financial strategies

1 Senior unsecured credit ratings shown.

May 9, 2008 6 EDISON INTERNATIONAL®

2008 Earnings Guidance

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Reconciliation of Core Earnings Guidance to GAAP Earnings Guidance

Core EPS1 2007 Results 2008 Guidance Reaffirmed as of 5/8/2008

Southern California Edison $ 2.07 $ 2.18 — $ 2.28

Edison Mission Group 1.72 1.57 — 1.87

EIX parent company and other (0.10) (0.14)

EIX core earnings per share $ 3.69 $ 3.61 — $ 4.01

Non-Core Items

Southern California Edison 0.10 — —

Edison Mission Group (0.46) — —

Total Non-Core Items $ (0.36) $ — — $ —

EIX GAAP earnings per share $ 3.33 $ 3.61 — $ 4.01

The current outlook for EIX 2008 Core Earnings is around the high end of the guidance range No change in Key Factors and Assumptions Provided on February 27, 2008

SCE

• 11.5% Return on Equity

• Energy Efficiency potential of $0.08 per share

EMG

• Forward hedge positions and prices as of 1/31/08

• EMMT pre-tax trading margin $75M

• Lower pre-tax earnings from EMG’s Sycamore and Watson projects

Other

• Excludes discontinued operations and non-core items

1 See Use of Non-GAAP Financial Measures in appendix. The impact of participating securities is $(0.04) per share for 2007 results and the expected impact of participating securities is $(0.05) per share for 2008 guidance and are included in EIX parent company and other. GAAP earnings per share refers to basic earnings per share.

May 9, 2008 7 EDISON INTERNATIONAL®

Southern California Edison (SCE)

Leading the Way in Electricity SM

An Investor-Owned Electric Utility

May 9, 2008 8 EDISON INTERNATIONAL®

SCE System

Leading the Way in Electricity SM

Largest electric utility in California

??13 million residents

??4.8 million customer accounts

??Almost 400,000 new connections over last five years

??50,000 square-mile service area Earnings model

??SCE earnings under CPUC jurisdiction rates are decoupled from demand consistent with California’s constructive regulatory model

??Earnings driven by approved rate of return on approved earning asset base

??Cost inflation forecast included in general rate case Infrastructure replacement and upgrades drives distribution system investment

??Almost 85% of transmission and distribution investment over last five years was for system improvements, not new customer connections

??2008 new connections forecast (~61,500) represents nearly 80% of five-year average and a decline of less than 10% from new connections in 2007

??2008 peak demand expected to grow ~2.5% above 23,303 MW record in 2007

California and SCE Service Territory

SCE Service Territory

May 9, 2008 9 EDISON INTERNATIONAL®

SCE Long-Term Resource Objectives

Leading the Way in Electricity SM

SCE Distribution System Supply and Demand Balance (MW)

Power Resource Needs

Supply Objectives

830

4,790

4,176

1,874

New Renewables

Other Projects Underway

1,339

319

Increased Demand 1 Requirement

Potential Retirements

Anticipated New Generation

New Demand-Side Resources

Potential Need by 20152

System Reliability

Price Stability

Environmental Considerations

Balance Objectives

Energy efficiency

Demand response

Renewable resources

Distributed generation

Clean fossil fuel generation

Load growth, retirements, and renewable mandates drive power resource needs

• ~6,700 MW new resources required

• ~1,350 MW new generation contracts awarded March 2008

1 Relative to 2007; data as of February 2008, includes planning reserve margin (PRM) of 15%. Source: 2006 SCE Long-Term Procurement Plan Final Decision; CEC November Load Forecast.

2 This number is without DPV2.

May 9, 2008 10 EDISON INTERNATIONAL®

SCE Renewable Energy Goals

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2007 Renewable Resources 12.5 Billion kWh

Renewable Resources 2007-2010 (Billion kWh)

Biomass 8%

Wind 21%

Solar 5% Small Hydro 4%

Geothermal 62%

12.5

28% Increase

2007 Actual Procurement

2010 Goal

SCE 2007 Renewable Energy Program

• 16% of SCE portfolio (RPS basis)

• ~1/8 of all US renewable electrons

• Over 90% of US solar energy

SCE 2010 Renewable Energy Goal

• Contracts are in place to meet 20% of customers’ energy requirements with renewable resources, but not by 2010

• Transmission constraints and unexpectedly high customer demand make it unlikely that 20% of 2010 energy will be delivered from renewable resources

• SCE will demonstrate compliance through continued, aggressive procurement efforts and use of flexible compliance rules

May 9, 2008 11 EDISON INTERNATIONAL®

SCE Capital Investment

Leading the Way in Electricity SM

Proposed $19.9 Billion Five-Year Capital Spending Plan

$ Billions

$5 $4.5 $4.6 $4.1

$4 $3.8 $2.9 $3

$2

$1

$0

2008 2009 2010 2011 2012

Forecast by Classification

$ % Solar Rooftop Program 0.85 4 Edison SmartConnectTM 1.25 6 Generation 2.50 13 Transmission 5.50 28 Distribution 9.80 49 Total1 19.90 100

Forecast by Type of Proceeding $ % CPUC Rate Cases 11.8 59 CPUC Project Specific 2.6 13 FERC Rate Cases 5.5 28 Total1 19.9 100

In 2008 SCE anticipates regulatory approval on a substantial portion of its capital spending program

1 Subject to timely receipt of permitting, licensing and regulatory approvals. Forecast is as of March 2008 and includes $692 million of capital spending for DPV2, the majority of which is expected to occur in 2009 and 2010. The Arizona Corporation Commission (ACC) denied approval of the DPV2 project. The denial has resulted in a minimum two-year delay of the project. SCE has initiated pre-filing activities with the FERC and is continuing to work with ACC on acceptable alternatives. Solar rooftop program announced on March 27, 2008.

May 9, 2008 12 EDISON INTERNATIONAL®

SCE’s Earning Asset Base

Leading the Way in Electricity SM

Forecast SCE Rate Base 2007-20121

$ Billions $25

$20 $15 $10 $5 $0

2007 2008 2009 2010 2011 2012

1 2 + % Compound Annual Growth

$15.5

$11.7 $12.7

$18.3

$23.6

$21.3

Effective execution of its capital expenditure program and continued regulatory support could double SCE’s earning asset base by 2012

1 Includes impact of 2006 CPUC and 2006 FERC GRC decisions and forecasted rate base for FERC (2007-2012) and CPUC (2009-2012) which are subject to timely receipt of permitting, licensing and regulatory approvals; includes estimated impacts of the November 15, 2007 FERC incentives decision allowing construction work-in-progress (CWIP) recovery in rate base and the Economic Stimulus Act of 2008. Forecast is as of March 2008 and includes $692 million of capital spending for DPV2, the majority of which is expected to occur in 2009 and 2010. The Arizona Corporation Commission (ACC) denied approval of the DPV2 project. The denial has resulted in a minimum two-year delay of the project. SCE has initiated pre-filing activities with the FERC and is continuing to work with ACC on acceptable alternatives.

May 9, 2008 13 EDISON INTERNATIONAL®

SCE Transmission Investment Program

Leading the Way in Electricity SM

• Tehachapi transmission line to interconnect up to 4,500 MW of generation

• New transmission needed to strengthen system reliability and access economical power

NEVADA CALIFORNIA

Las Vegas Midway Tehachapi SCE Eldorado

(PG&E) Service

Windhub

Territory

Antelope Palmdale Lugo

Vincent Mohave ARIZONA Santa Clarita Pardee RanchoVista MiraLoma Devers Los Angeles Serrano PalmSprings Phoenix Valley SantaAna Verde Palo

San Diego

Existing 500kV Tehachapi Segments 1-3 500kV DPV2 & Rancho Vista 500kV Tehachapi Segments 4-11 500kV

Project Name Phase 2008-2012 In-Service ($ Millions)1 FERC Adders (bps)3

Renewables

Tehachapi Segments 1–3 Construction 2008-2009 328 175 Tehachapi Segments 4–11 Licensing 2011-2013 1,742 175 Other Projects Licensing Various 933 —Total Renewables 3,003

Reliability

Rancho Vista Substation Construction 2009 192 125 Other Projects Various Various 1,589 —Total Reliability 1,781

Economics

DPV2 Licensing2 2011 692 175 Total Economics 692

Grand Total 5,476

FERC investment incentives will provide important earnings and cash flow benefits as FERC earning asset base is forecast to more than double from 10% of rate base in 2007 to over 20% by 2012

1 Subject to timely receipt of permitting, licensing and regulatory approvals. Forecast is as of February 2008.

2 All approvals have been received except the Bureau of Land Management and the Arizona Corporation Commission (ACC). The ACC denied approval of the DPV2 project. The denial has resulted in a minimum two-year delay of the project. SCE has initiated pre-filing activities with the FERC and is continuing to work with ACC on acceptable alternatives.

3 Includes 50 b.p. ROE adder for belonging to CAISO, 125 b.p. project specific adder for Tehachapi & DPV2, and 75 b.p. project specific adder for Rancho Vista.

May 9, 2008 14 EDISON INTERNATIONAL®

SCE Edison SmartConnectTM Program

Leading the Way in Electricity SM

Phase III Meter Installation Timeline Cumulative Capital Spending & Meter Installations

2008 2009 2010 2011 2012

$100 M $450 M $800 M $1,100 M $1,245 M

– 1.4 M 3.0 M 4.6 M 5.3 M

Highlights

• Phase III application filed July 2007 to deploy to 5.3 million residential and small commercial customers between 2008 – 2012

• Estimated total project cost is $1.7 billion, of which approximately $1.25 billion is capital cost to be included in rate base1

• SmartConnectTM combines the efforts of IBM, Itron and eMeter to manage system integration, meter technology and data management, respectively

• Edison SmartConnectTM has the potential to reduce peak power consumption by as much as 1,000 MW and reduce GHG emissions by 365,000 metric tons per year

Integrate Homes with the Utility Circuit

Integrate Smart Appliances with the Home

SCE leadership in advanced metering infrastructure

1 Subject to CPUC approval.

May 9, 2008 15 EDISON INTERNATIONAL®

Nation’s Leader in Energy Efficiency

Leading the Way in Electricity SM

1992 to 2006 National EE Leaders 1

GWh

10,000 9,000 8,000 7,000 6,000 5,000 4,000 3,000 2,000 1,000 0

SCE PG&E NSP FPL CL&P

9,031

7,090

4,041 3,863

2,226

EE Milestones

SCE has 69 energy efficiency programs, providing financial incentives and/or other benefits for saving energy and shifting usage from on-peak periods During the past 5 years –

• SCE customers have saved more than 5 billion kWhs –enough to power over 700,000 homes for an entire year

• SCE has reduced greenhouse gas emissions by 2 million metric tons – the equivalent of taking 375,000 cars off the road SCE has consistently won national recognition including:

• 7 United States Department of Energy “Energy Star” awards

• 2 Environment Protection Agency “Stratospheric Ozone Protection” awards, including the “Best of the Best International Stratospheric Ozone Protection Award” for 2007

• Alliance to Save Energy “Star of Energy Efficiency” award

American Council for an Energy Efficient Economy “Champion of Energy Efficiency” award

SCE’s strong performance history in EE coupled with a constructive regulatory environment has SCE poised for future success

1 US Department of Energy, Energy Information Administration.

May 9, 2008 16 EDISON INTERNATIONAL®

SCE Energy Efficiency Earnings Opportunity

Leading the Way in Electricity SM

CPUC Approved Energy Efficiency (EE) Shareholder Incentive Mechanism1

2006-2008 EE Cycle

Year 2006 2007 2008

2009-2011 EE Cycle

2009 2010 2011 2012 2013

Potential Earnings Profile by Year3

65% of 2006-2007 earnings opportunity2

65% of 2008 earnings opportunity

35% of 2006-2008 earnings opportunity plus true-up

65% of 2009-2010 earnings opportunity2

65% of 2011 earnings opportunity

35% of 2009-2011 earnings opportunity plus true-up

SCE, the national leader in energy efficiency, is targeting $1.2 billion in net customer savings and an earnings opportunity of up to ~$146 million (pre-tax) for 2006-20084

1 Based upon September 20, 2007 and January 31, 2008 decisions released by the California Public Utilities Commission (CPUC).

2 There is no assurance of earnings in any given year. If approved by the CPUC, SCE currently projects, based on preliminary results, that it will record a progress payment in the range of $41 million to $49 million in the fourth quarter of 2008 for the years (2006-2007) of the program cycle. SCE expects to collect this progress payment in rates in 2009. SCE is scheduled to file advice filings in September of each year requesting recovery of the progress payments. SCE expects it will recognize earnings in the amount of the progress payments upon CPUC acceptance of its filing, expected in the fourth quarter of each year.

3 Assumes SCE achieves all of its energy efficiency goals, and delivers customer benefits of approximately $1.2 billion. Based on forecast, cash is received in the year following the period when earnings are recognized.

4 The January 2008 modifications incorporate an update to the effective useful life of the energy efficiency measures installed. If the draft CPUC effective useful life study is adopted in its current form, the effective useful life of residential compact fluorescent lights, one of the largest contributors to SCE’s energy efficiency portfolio, would be reduced and SCE’s earnings opportunity would decrease to approximately $124 million.

May 9, 2008 17 EDISON INTERNATIONAL®

SCE Solar Rooftop Program

Leading the Way in Electricity SM

Install 250 MW of solar photovoltaic generation on leased commercial rooftops

1-2 MW average installations target significant cost economies of scale

May seek future authority to expand to 500 MW program

$875 million capital spending program1

100 b.p. premium for utility-owned renewable generation (SCE’s CPUC-approved return on equity is 11.5% for 2008)

SCE has requested authority to recover costs incurred during regulatory approval process to facilitate a 2008 program launch

Operating costs would be recovered through a balancing account with after-the-fact reasonableness review until included in base rates as part of general rate cases

SCE’s proposed rooftop solar program will help advance California public policy and help build scale for the large rooftop photovoltaic solar market

1 Subject to CPUC approval. Direct capital forecast in 2008 dollars (2008-2013).

May 9, 2008 18 EDISON INTERNATIONAL®

Constructive Regulatory Environment

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What’s Changed Since the Power Crisis

Advance approval of annual procurement plans for purchased power

Trigger mechanism for fuel and purchased power cost recovery

Forward-looking rate-making includes expected cost inflation

State support for reliable electric system infrastructure

Benefits to Customers and Investors

Upfront review of utility purchasing decisions through a defined procurement plan

Better matching of revenues and cash expenditures for fuel and purchased power costs with predetermined trigger mechanisms for recovering higher costs

Three-year process based on forecast expenses, capital spending and asset base increases between rate cases

Regulatory decisions address emerging issues (such as adding peaking capacity for 2007 summer season) and opportunities (new energy efficiency program and incentives for utility renewable energy investment)

California’s regulatory framework has been strengthened to support growth and reliability needs, while longstanding decoupling policies mitigate risks of volatile commodity prices and economic slowdown

May 9, 2008 19 EDISON INTERNATIONAL®

Renewable Transmission Planning

Leading the Way in Electricity SM

Renewable Transmission Planning

Objective

Build a robust renewable transmission system that balances all requirements

Delivery Capacity System reliability and power quality Schedule Cost

Challenges

Technical: Integrating Intermittent resources Regulatory: Requirements, Processes Financial: Capital, Cost recovery, Customer rates

May 9, 2008 20 EDISON INTERNATIONAL®

Electric Technology Solutions to Meet the Climate Change Challenge

Leading the Way in Electricity SM

Advanced Generation

Smart Grid/Smart Connect

Grid-connected Transportation

Technology Advancement Delivers Required GHG Responses

Low Carbon Fuel Mix

Demand-Side Management & Efficiency

While protecting customers:

• Mitigate rate shocks, and ensure fair cost responsibility within electric industry and across other industries

• Meet customer expectations for value (reliable service and improved power quality)

May 9, 2008 21 EDISON INTERNATIONAL®

Edison Mission Group (EMG)

Leading the Way in Electricity SM

A Competitive Power Generation Company

May 9, 2008 22 EDISON INTERNATIONAL®

EMG Business Platform

Status at March 31, 2008

Leading the Way in Electricity SM

Washington

Natural Gas 70 MW

California

Natural Gas 964 MW

Natural Gas (Pipeline) 479 MW

Arizona

Wind (Pipeline) 1,140 MW

Wyoming

Wind (UC) 141 MW

Utah

Wind (Pipeline) 70 MW Wind (UC) 19 MW

Oklahoma

Wind 95 MW

Wind (Pipeline) 300 MW

Nevada

Wind (Pipeline) 515 MW

New Mexico

Wind 90 MW

Wind (Pipeline) 1,070 MW

Texas

Wind 161 MW Wind (UC) 150 MW Wind (Pipeline) 400 MW

Iowa

Wind 145 MW

Wind (Pipeline) 200 MW

Minnesota

Wind 75 MW Wind (UC) 70 MW Wind (Pipeline) 130 MW

Nebraska

Wind (Pipeline) 80 MW

Illinois

Coal 5,471 MW Natural Gas 305 MW Wind (Pipeline) 520 MW

Maryland

Wind (Pipeline) 95 MW

Wisconsin

Wind (Pipeline) 100 MW

New York

Wind (Pipeline) 140 MW

West Virginia

Coal 40 MW

Wind (Pipeline) 232 MW

Pennsylvania

Coal 1,884 MW Wind (UC) 67 MW

Operating Platform1

MW % Coal 7,395 79 Natural Gas 1,339 14 Wind 566 5 Other 153 2 9,453 100

Wind Development Pipeline2

MW Under Construction 447 Pipeline 4,992 Turbines (Not Shown) 1,166

Thermal Pipeline3

MW Natural Gas 479

1 Natural gas includes oil-fired; other includes Doga in Turkey (144 MW) and Huntington biomass (9 MW) which are not shown.

2 Owned or under exclusive agreement. Turbines purchased or committed to support development pipeline.

3 Contract award subject to regulatory approval with planned on-stream date June 2013.

May 9, 2008 23 EDISON INTERNATIONAL®

EMG Coal-Fired Fleet

Leading the Way in Electricity SM

Midwest Generation

• 5,776 MW – Six facilities and peakers acquired in 1999

• Powder River Basin coal (PRB)

• Rail under contract through 2011

• Operational Statistics: 2005 2006 2007 Total Generation (GWh) 30,953 28,898 29,961 Load Factor 79.1% 74.1% 80.4%

Homer City

• 1,884 MW – Three units acquired in 1999

• Northern Appalachian coal (NAPP)

• Largely sourced locally and delivered by truck

• Operational Statistics: 2005 2006 2007 Total Generation (GWh) 13,637 12,286 13,649 Load Factor 96.7% 90.7% 92.4%

All-in Average Realized Prices1

$/MWh

$60 $40 $20 $0

$53

$46 $47

$40

$34 $34

$12 $13 $13

2005 2006 2007

All-in Average Realized Prices1

$60 $40 $20 $0

$56 $49 $46 $34 $26 $25

$21 $23 $22 2005 2006 2007

Average realized gross margin ($/MWh)2 Average fuel and emission costs ($/MWh)

1 Includes the price of energy, capacity, ancillary services, etc.

2 Average realized gross margin is equal to all-in average realized prices less average fuel and emission costs.

May 9, 2008 24 EDISON INTERNATIONAL®

EMG Hedge Program Status

Leading the Way in Electricity SM

Status at March 31, 2008 – No Significant Hedging Activity in 1Q 08

Remainder of

2008 2009 2010

Midwest Generation

Energy Only Contracts

Megawatt Hours 7,746 7,692 3,472

Average Price ($/MWh) $60.85 $62.38 $62.58

Load Requirement Services Contracts

Estimated MWh1 3,689 1,571 —

Average Price ($/MWh)2 $64.21 $63.65 —

Total estimated GWh hedged 11,436 9,263 3,472

Coal under contract (in millions of tons) 12.3 11.7 11.7

Homer City

Total estimated GWh hedged 5,434 2,867 1,022

Average Price ($/MWh)3 $60.84 $73.84 $77.80

Coal under contract (in millions of tons) 4.3 4.4 0.4

1 The amount of power sold is a portion of the retail load of the purchasing utility and can vary significantly with variations in that retail load. Retail load depends upon a number of factors, including the time of day and year, and the utility’s number of new and continuing customers. Estimated MWh have been forecast based on historical patterns and on assumptions regarding the factors that may affect retail loads in the future. The actual load will vary from that used for the above estimate, and the amount of variation may be material.

2 The average price per MWh, which is subject to a seasonal price adjustment, represents the sale of a bundled product that includes, but is not limited to, energy, capacity and ancillary services. Also, Midwest Generation will incur charges from PJM as a load-serving entity. Thus, the average price per MWh is not comparable to the sale of power under an energy only contract. The average price per MWh represents the sale of the bundled product based on an estimated customer load profile.

3 The average price/MWh for Homer City’s hedge position is based on PJM West Hub prices. As a result of transmission congestion in the PJM, actual energy prices at the Homer City busbar have been lower than those at the PJM West Hub.

May 9, 2008 25 EDISON INTERNATIONAL®

EMG Capacity Sales

Leading the Way in Electricity SM

Status at March 31, 2008 – No New Capacity Auctions in 1Q 08

Apr 1, 2008 — May 31, 2008 Jun 1, 2008 — May 31, 2009 Jun 1, 2009 — May 31, 2010 Jun 1, 2010 — May 31, 2011

Megawatts except price per MW-day Midwest Generation Homer City Midwest Generation Homer City Midwest Generation Homer City Midwest Generation Homer City

Installed Capacity 5,776 1,884 5,776 1,884 5,776 1,884 5,477 1,884

Less: Net capacity held due to load

requirement services contracts,1

and retained for outages (2,647) (173) (1,942) (159) (447) (214) (548) (71)

Net Capacity Available for Sale 3,129 1,711 3,834 1,725 5,329 1,670 4,929 1,813

Fixed Price Capacity Sales

RPM Auction Process

• Net Capacity Sold3 2,629 786 2,978 820 4,614 1,670 4,929 1,813

• Price per MW-day3 $37.27 $40.80 $123.77 $113.22 $102.04 $191.32 $174.29 $174.29

Non-unit Specific Capacity Sales

• Net Capacity Sold 500 — 880 — 715 — — —

• Price per MW-day (Net) $21.31 $ — $64.35 $ — $71.46 $ — $ — $ —

Variable Capacity Sales

Third Party Transaction

• Capacity — 925 — 905 — — — —

• Expected price per MW-day2 $ — $70.37 $ — $63.96 $ — $ — $ — $ —

Total Capacity Sold 3,129 1,711 3,858 1,725 5,329 1,670 4,929 1,813

Average Price per MW-Day $34.72 $56.79 $110.22 $87.38 $97.94 $191.32 $174.29 $174.29

1 Load requirements services contracts include energy, capacity and ancillary services.

2 Actual contract price for Homer City sale is a function of NYISO capacity auction clearing prices. Expected price per MW-day is based on forward over-the-counter NYISO prices on March 31, 2008.

3 During 1Q 08, PJM updated capacity prices for the period June 1, 2008 to May 31, 2009 to reflect the final incremental auction for this planning year. Homer City’s adjusted prices for capacity per megawatt hour is $113.22 compared to the original price of $111.92. In addition, the price was affected by Midwest Generation’s participation in a supplemental RPM auction which resulted in purchasing certain capacity amounts at a price of $10/MW-day, thereby reducing the aggregate forward capacity sales for this period and increasing the effective capacity price to $123.77 at March 31, 2008.

May 9, 2008 26 EDISON INTERNATIONAL®

Edison Mission Marketing & Trading (EMMT)

Leading the Way in Electricity SM

• Optimize forward sales opportunities

?Extending hedge program

?Reducing collateral requirements

• EMMT provides opportunistic trading revenues

?Leverages knowledge gained from managing merchant coal fleet

?Trading primarily transmission congestion products and electricity basis spreads

?Entering California and Texas markets

• Controls on types and sizes of exposures

?Allowed products and region (large majority of positions are low-risk congestion contracts)

?VaR, volumetric, duration and credit limits

EMMT Trading Margin (pre-tax)1

$ millions

$250 $200 $150 $100 $50 $0

$195

$130 $143

$34 $23

2003 2004 2005 2006 2007

EMMT provides significant incremental income from trading activity

1 Income from energy trading represents gains recognized from trade price changes. The overhead cost of energy trading is excluded.

May 9, 2008 27 EDISON INTERNATIONAL®

EMG Environmental Compliance

Leading the Way in Electricity SM

MWG Compliance Plan

Phase I – Mercury Reductions

??90% removed by 2015

??Installation of Activated Carbon Injection (ACI) technology by July 2009

??Estimated cost of $60 million

Phase II – NOx Reductions

?Emissions of .11 lbs. per million Btus by 2011 (66% reduction)

?Installation of primarily Selective Catalytic Reduction (SCR) systems by the end of 2011

?Estimated cost of $450 million

Phase III – SO2 Reductions

?Emissions of .11 lbs. per million Btus by 2019, with interim step-down (78% reduction)

?Flue Gas Desulfurization (FGD) technology

?Estimated cost $2.2 – $2.9 billion

Homer City Compliance Plan

• PA State Implementation Plan for CAMR and CAIR adopted

• Homer City expects to comply with the 2010 phase of mercury requirements by installing ACI on Units 1 & 2

EMG is conducting a competitive process to select an equipment supplier and EPC contractor for Powerton, Illinois environmental upgrades.

Based on this process, EMG expects to update environmental capital expenditure estimates in 2008.

Note: Cost estimates are in 2006 dollars.

May 9, 2008 28 EDISON INTERNATIONAL®

Wind Energy Development Strategy & Portfolio

Leading the Way in Electricity SM

Wind Energy Development Strategy

• Strategic importance to growth plan

?Contributes to portfolio diversification

?Objective is to attain national scope and leadership scale

?Leverages successful wind energy experience to date

• Wind energy provides attractive opportunities

?Growing RPS requirements and national desire for renewables

?Production tax credits

?Accelerated depreciation (MACRS) over 5 years

?Mainly long-term contracts for output

Wind Project Portfolio & Development Pipeline

Projects1 No. of Projects MW

In-Service 13 566 Under Construction 8 447

Total Projects 21 1,013 Development Pipeline 33 4,992

Turbines

Purchased and under option 1,166

• Development pipeline includes projects owned or under exclusive agreements

• Turbines purchased and under option support development pipeline

• Working through wind turbine generator blade issues with Suzlon and Clipper

1 Data as of March 31, 2008.

May 9, 2008 29 EDISON INTERNATIONAL®

Other EMG Growth Opportunities

Leading the Way in Electricity SM

Natural

Gas-Fired

Generation

• Walnut Creek, CA – Awarded 10-year power purchase agreement with Southern California Edison for 479 MW –Online June 1, 2013

• Sun Valley, CA opportunity (500 MW) in permitting and engineering stage

• Potential acquisitions of assets or portfolios

??Will be selective and disciplined

??Complement marketing and trading skills

Solar

Evaluating investment opportunities in solar power generation

Clean-Coal

Technologies

Continuing to investigate clean coal technologies

??Carbon capture

??Post-combustion options

May 9, 2008 30 EDISON INTERNATIONAL®

Our Shareholder Value Proposition

Leading the Way in Electricity SM

• Attractive business portfolio and growth opportunities

• Southern California Edison

??Demonstrated need for utility infrastructure investments

??Among the best domestic electric utility growth platforms

• Edison Mission Group

??Favorable market conditions for unregulated generation portfolio

??Strong growth pipeline led by renewable investments

• Commitment to long-term shareholder value creation

• Incentive compensation and stock ownership guidelines consistent with shareholder interests

• Edison people committed to excellence in safety and customer service

May 9, 2008 31 EDISON INTERNATIONAL®

Appendix

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May 9, 2008 32 EDISON INTERNATIONAL®

SCE Regulatory Update

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Case Date of Next

Number Filing Status Milestone

2009 GRC A. 07-11-011 November 2007 GRC Application filed and CPUC schedule approved. DRA and other intervenor recommendations received. SCE rebuttal to be filed 5/13/08 Evidentiary hearings begin 5/29/08 Proposed decision expected 11/4/08 Final Decision expected 12/4/08

Cost of Capital (COC) Multi-Year Program A. 07-05-003 May The possibility of a multi-year cost of 2007 capital mechanism, as opposed to annual Initial comments due 5/19/08 Final Decision expected 5/29/08 filings. Proposed Decision issued 4/29/08.

Tehachapi Transmission A. 04-12-007/8 (Segments 1-3) A. 07-06-031 (segments 4-11) December 2004 June 2007 Decision Granted D. 07-03-012 / 045 Pre-hearing conference held August, 2007. Supplemental cost testimony filed in October, 2007 Construction began March 2008 Draft EIR/EIS scheduled August, 2008. Decision anticipated late 2008 / early 2009

DPV 2 – Transmission1 ACC: L-00000A-06- 0295-00130 May 2006 ACC denied approval of application in May, 2007 Initiated pre-filing activities with FERC. on Continuing acceptable to alternatives. work with ACC

Edison SmartConnectTM Phase III A. 07-07-026 July 2007 Phases I and II approved Phase III filed Final Phase III decision expected August 2008

Capacity Market R. 05-12-013 December 2005 Awaiting intervenor comments on Phase 2/Track 2 proposals, comments due March 14, 2008 Final Decision expected May 2008

SCE Solar Rooftop Program A. 08-03-015 March 2008 Application and testimony filed Commission approves memorandum account for start- up activites

1 CPUC has approved (A. 05-04-015) and FERC has declared the region a National Interest Electric Transmission Corridor (N.I.E.T.C.).

May 9, 2008 33 EDISON INTERNATIONAL®

First Quarter Financial Results

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Reconciliation of Core Earnings to GAAP Earnings

Core Earnings 1Q 07 1Q 08 Variance

SCE $ 0.45 $ 0.46 $ 0.01

EMG 0.48 0.49 0.01

EIX parent company (0.03) (0.03) —and other

Core EPS1 $ 0.90 $ 0.92 $ 0.02

Non-core Items

SCE $ 0.10 $ ? $ (0.10)

EMG 0.01 (0.01) (0.02)

Total Non-Core $ 0.11 $ (0.01) $ (0.12) Basic EPS $ 1.01 $ 0.91 $ (0.10) Diluted EPS $ 1.00 $ 0.91 $ (0.09)

Core Earnings Variances SCE

Lower net interest expense 0.01

EMG

Midwest Generation

Higher gross margin mainly from higher realized prices, lower 0.12 interest expense and favorable buy-out of a coal contract

EMMT2

Higher income from energy trading 0.03

Homer City

Lower generation and realized prices (0.02)

Edison Capital

Lower gains from Global Infrastructure Funds (0.03)

Income from other projects (0.03) Corporate expense and other items

Higher EME interest expense and higher expenses related to (0.06) growth activities

Non-Core Variances

SCE 1Q 07: Resolution of the tax treatment of certain (0.10) environmental remediation costs EMG 1Q 07: Lakeland distributions $0.01; 1Q 08: Foreign (0.02) exchange losses on contract indemnity ($0.01)

1 See Use of Non-GAAP Financial Measures in appendix. The impact of participating securities is included in EIX parent company and other, and was $(0.01) per share for each of the quarters ended March 31, 2008 and 2007.

2 EMMT overhead is included in Corporate expense and other items.

May 9, 2008 34 EDISON INTERNATIONAL®

EMG – First Quarter Adjusted EBITDA

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Reconciliation to Net Income ($ Millions) 1Q 07 1Q 08

Net income $ 159 $ 154 Addback (Deduct): Discontinued operations (3) 5 Income from continuing operations 156 159 Interest expense 91 73 Interest income (30) (11) Income taxes 77 83 Depreciation and amortization 37 46

EBITDA1 331 350

Production tax credits2 5 9

Adjusted EBITDA1 $ 336 $ 359

1 See Use of Non-GAAP Financial Measures for additional information on EBITDA and Adjusted EBITDA.

2 Production tax credits (PTC) are after-tax.

May 9, 2008 35 EDISON INTERNATIONAL®

EMG Adjusted EBITDA

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Reconciliation to Net Income ($ Millions) 2006 2007

Net income $ 432 $ 410 Addback (Deduct): Discontinued operations (97) 2 Income from continuing operations 335 412 Interest expense 409 323 Interest income (118) (101) Income taxes 154 170 Depreciation and amortization 157 172

EBITDA1 937 976

Production tax credits2 17 28 Discrete items: Gain on sale of assets (22) (1) Loss on early extinguishment of debt 146 241

Adjusted EBITDA $ 1,078 $ 1,244

1 See Use of Non-GAAP Financial Measures for additional information on EBITDA and Adjusted EBITDA.

2 Production tax credits (PTC) are after-tax.

May 9, 2008 36 EDISON INTERNATIONAL®

EMG Capital Expenditures

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Estimated Expenditures1 2008 – 2010

Projects Under Construction Wind Turbine Commitments Plant/Corporate Capex Plan Environmental Plan

$ Millions $1,000

$800 $600 $400 $200 $0

2008 2009 2010

$817 $843

$449

Total $2,109 Million

Estimated Expenditures (2008 – 2010)

Additional growth opportunities Additional wind turbines

Balance of plant costs for purchased wind turbines Homer City will comply with 2010 phase of mercury requirements

Estimated Expenditures After 2010

Midwest Generation environmental spending plan Evaluating FGD installation at Homer City Additional growth opportunities

1 EMG expects to make substantial investments in new projects during the next three years. As of March 31, 2008, EMG had a development pipeline of potential wind projects with an estimated installed capacity of approximately 5,000 MW (the development pipeline represents potential projects for which EME either owns the project rights or has exclusive negotiation rights). Completion of these projects is dependent upon a number of items which may include, depending on the project’s status, completion of a power sales agreement, permits, an interconnection agreement or other agreements necessary to start construction. Additional projects may from time to time be added to the development pipeline, and there is no assurance that the projects included in the development pipeline currently or added in the future will lead to the successful completion of a wind project. 2008 expenditures are for the period April 1 – December 31, 2008.

May 9, 2008 37 EDISON INTERNATIONAL®

Liquidity Profile

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Available Liquidity at March 31, 2008

Sources ($ in Millions) SCE EMG EIX Parent Co. & Other Total1

Credit Facility $ 2,500 $ 1,100 $ 1,500 $ 5,100

Credit Facility (availability) $ 1,883 $ 937 $ 1,500 $ 4,320

Cash & short term investments2 283 1,222 75 1,580

Available Liquidity $ 2,166 $ 2,159 $ 1,575 $ 5,900

1 Total amounts do not imply any credit support among entities except as specified in each credit facility.

2 SCE amount includes $113 million held by SCE’s consolidated variable interest entities.

May 9, 2008 38 EDISON INTERNATIONAL®

Midwest Generation – Operating Performance

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1Q 07 vs. 1Q 08

• Generation lower by 2.9% in 1Q 08 largely due to a forced outage at Powerton

• Higher load factor

Operating Statistics 1Q 07 1Q 08

Total Generation (GWh) 8,630 8,383 Equivalent Availability 88.0 % 82.5 % Capacity Factor 71.2 % 70.3 % Load Factor 80.9 % 85.3 % Forced Outage Rate 5.9 % 11.8 %

All-in average realized price increased 7% in 1Q 08 compared to last year

All-in Average Realized Prices1

$/MWh

$60 $40 $20 $0

$56.24

$52.31

$42.16

$39.68

$12.63 $14.08

1Q 07 1Q 08

Average realized gross margin ($/MWh)2 Average fuel and emission costs ($/MWh)

1 Includes the price of energy, capacity, ancillary services, etc.

2 Average realized gross margin is equal to all-in average realized prices less average fuel and emission costs.

May 9, 2008 39 EDISON INTERNATIONAL®

Homer City – Operating Performance

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1Q 07 vs. 1Q 08

• Generation lower by 3.1% reflecting higher forced outage rate and lower off-peak demand

Operating Statistics 1Q 07 1Q 08

Total Generation (GWh) 3,293 3,192 Equivalent Availability 86.5 % 87.5 % Capacity Factor 80.8 % 77.5 % Load Factor 93.3 % 88.5 % Forced Outage Rate 5.8 % 9.5 %

All-in average realized price decreased 2% in 1Q 08 compared to last year

All-in Average Realized Prices1

$/MWh

$60 $40 $20 $0

$59.72 $58.42

$37.91 $35.85

$21.81 $22.57

1Q 07 1Q 08

Average realized gross margin ($/MWh)2 Average fuel and emission costs ($/MWh)

1 Includes the price of energy, capacity, ancillary services, etc.

2 Average realized gross margin is equal to all-in average realized prices less average fuel and emission costs.

May 9, 2008 40 EDISON INTERNATIONAL®

Use of Non-GAAP Financial Measures

Leading the Way in Electricity SM

Edison International’s earnings are prepared in accordance with generally accepted accounting principles used in the United States and represent the company’s earnings as reported to the Securities and Exchange Commission. Our management uses core earnings and EPS by principal operating subsidiary internally for financial planning and for analysis of performance. We also use core earnings and EPS by principal operating subsidiary as primary performance measurements when communicating with analysts and investors regarding our earnings results and outlook, as it allows us to more accurately compare the company’s ongoing performance across periods. Core earnings exclude discontinued operations and other non-core items and are reconciled to basic earnings per common share.

EPS by principal operating subsidiary is based on the principal operating subsidiary net income and Edison International’s weighted average outstanding common shares. The impact of participating securities (vested stock options that earn dividend equivalents that may participate in undistributed earnings with common stock) for each principal operating subsidiary is not material to each principal operating subsidiary’s EPS and is therefore reflected in the results of the Edison International holding company, which we refer to as EIX parent company. EPS and core EPS by principal operating subsidiary are reconciled to basic earnings per common share.

EBITDA is defined as earnings before interest, income taxes, depreciation and amortization. Adjusted EBITDA includes production tax credits from EMG’s wind projects and excludes amounts from gain on the sale of assets, loss on early extinguishment of debt and leases, and impairment of assets and investments. Our management uses Adjusted EBITDA as an important financial measure for evaluating EMG.

A reconciliation of Non-GAAP information to GAAP information, including the impact of participating securities, is included either on the slide where the information appears or on another slide referenced in the presentation.

May 9, 2008 41 EDISON INTERNATIONAL®