March 07, 2008 March 7, 2008 MOJAVE, Calif., March 7, 2008 — In the most recent demonstration of its national leadership role in renewable and alternative energy, Southern California Edison (SCE) has begun construction of the largest wind transmission project in the United States. When all phases are developed, the Tehachapi Renewable Transmission Project will include a series of new and upgraded high-voltage transmission lines capable of delivering 4,500 megawatts of electricity from wind farms and other generating companies in Northern Los Angeles and Eastern Kern counties. The first three segments include the following components: two new substations —Windhub and Highwind — located near Mojave and Monolith; a new, 25.6 mile, 500 kilovolt transmission line connecting SCE’s existing Antelope Substation with the new Windhub Substation; a new, 9.6 mile, 220 kilovolt transmission line connecting the Windhub Substation and the Highwind Substation; a new, 21.0-mile, 500 kilovolt transmission line connecting SCE’s existing Antelope and Vincent substations; and a new, 26.7-mile, 500 kilovolt transmission line connecting SCE’s existing Antelope and Pardee substations. The new lines are expected to be operational in early 2009. “Southern California Edison is the nation’s leader in renewable and alternative energy, and we are continually looking for ways to expand our renewables portfolio,” said Alan J. Fohrer, chairman and chief executive officer of Southern California Edison, the utility subsidiary of Edison International. “The Tehachapi project is an example of the company finding a progressive way to meet increased energy demands of our customers and meet state officials’ desires to enhance the state’s renewables portfolio.” The Tehachapi project is the first major transmission project in California being built specifically to access multiple renewable generators in a remote renewable-rich resource area. When complete, it will be part of a comprehensive $1.8 billion program to provide the high-voltage transmission infrastructure necessary to interconnect and deliver the renewable wind resources being developed in the Tehachapi Wind Resource Area to California electricity customers. Completing the Tehachapi project is an important component to meeting California’s renewable energy goals. “Construction of the Tehachapi project will create the single largest power block of wind energy in the United States,” said Michael Peevey, president of the California Public Utilities Commission (CPUC). “Our action today represents a critical step in alleviating the transmission constraints that have limited our ability to access substantial wind resources in the Tehachapi region.” Other phases of the project are in the regulatory and approval stage. The project, if completed in 2013 as proposed, would be capable of carrying 4,500 megawatts of electricity, enough energy to supply nearly 3 million homes at peak output. One megawatt is enough power to serve about 650 average homes at a given point in time. “The Tehachapi project not only will facilitate the interconnection of new wind generation, but also will improve grid reliability to help meet the state’s growing demand for electricity with renewable energy,” said Dian Grueneich, the lead CPUC commissioner on the Tehachapi project. In addition to bringing significant wind energy resources to the California transmission grid, the Tehachapi project will provide many other meaningful benefits, including: Improving the reliability of the California transmission grid by enabling the expansion of the transfer capability of “Path 26,” one of the state’s most important north/south transmission corridors. Serving the growth in energy demand in the Antelope Valley. Easing transmission constraints into the Los Angeles basin. The Tehachapi project is part of SCE’s five-year, $5 billion transmission expansion program designed to ensure that Southern California has the robust power delivery system needed by a growing region. SCE is the nation’s leading purchaser of renewable energy. In 2006, SCE delivered about 13 billion kilowatt-hours of renewable energy, 17 percent of its total power deliveries — enough renewable energy to serve 1.8 million homes for an entire year. Energy contracts signed by SCE from 2002 through 2007 account for approximately 4,200 megawatts of SCE’s renewable energy portfolio, the equivalent of about four major power plants. Media Contact: Paul Klein, (626) 302-2255www.edisonnews.com # # # An Edison International (NYSE:EIX) company, Southern California Edison is the largest electric utility in California, serving a population of more than 13 million via 4.8 million customer accounts in a 50,000-square-mile service area within Central, Coastal and Southern California.