The California Independent System Operator (California ISO) issued a Transmission Emergency at 6:22 p.m. today Monday, March 8, 2004 after power lines in the central portion of the state overloaded. ISO operators gave instructions to Southern California Edison (SCE) to "shed load" or rotate customers off the grid for 20 minutes between about 6:30 and 6:50 p.m. The power outage affected about 70,000 SCE customers.

The emergency came after warmer than anticipated temperatures caused a spike in electricity demand in Southern California. The ISO had anticipated the higher demand for electricity and many power plants were ordered on to meet this first high electrical load of the year. The units were in the process of "ramping up" output, when demand outpaced their ability to generate and keep Path 26 from overloading. The ISO will conduct a full investigation into the cause of the transmission emergency and report the findings.

The California ISO is a not-for-profit public benefit corporation charged with managing the flow of electricity along California's wholesale power grid. The mission of the California ISO is to safeguard the reliable delivery of electricity, and ensure equal access to 25,000 circuit miles of "electron highway." As the impartial operator of the wholesale power grid in the state, the California ISO conducts a small portion of the bulk power markets. These markets allocate space on the transmission lines, maintain operating reserves and match supply with demand in real time.

Continuously updated information about the California ISO control area's electricity supply and the current demand on the power grid is available on the web at www.caiso.com.