July 20, 2004 July 20, 2004 ROSEMEAD, Calif., July 20, 2004–High temperatures and an ongoing heat wave today resulted in Southern California Edison supplying a record amount of energy to its customers, 20,144 megawatts (MW) of electricity. The new demand peak, achieved at 4 p.m., eclipsed the previous record of 20,136 MW set last year on Sept. 5, a Friday. Today’s record was achieved a day after the California Independent System Operator (Cal-ISO), which manages transmission and system reliability for 75% of the state, reported a record electrical “load” on the Cal-ISO system, 44,042 MW on Monday afternoon. That compares with the old record of 43,609 MW set July 12, 1999. [A megawatt is a unit of “instantaneous” power or demand, much as “horsepower” describes the amount of power an engine can produce at any given time. A megawatt of power is enough to serve 500 to 1,000 homes at any given moment.] Though there were no major problems securing generation for its customers, SCE has experienced difficulties contending with wildfires threatening its transmission lines. SCE is urging customers to use electricity prudently during the continuing heat wave, especially between the hours of noon and 7 p.m. Customers are encouraged to adjust air conditioner thermostats to 78 degrees (F) or higher, run optional household appliances and pool equipment during the early morning and evening hours, turn off lights in any unoccupied room or building, and use fans rather than air conditioning when practical. # # # An Edison International (NYSE:EIX) company, Southern California Edison is one of the nation’s largest electric utilities, serving a population of more than 12 million via 4.6 million customer accounts in a 50,000-square-mile service area within central, coastal and Southern California.