Heat wave to test Southern California power grid

Reuters 20 Jul 09;

NEW YORK (Reuters) - The largest utility in southern California urged consumer on Monday to conserve power to help keep air conditioners running without interruption as hot weather sends demand soaring over the next few days.

Temperatures in Los Angles will reach the low 90s Fahrenheit (low 30s Celsius) Monday and Tuesday with the humidity making it feel more like the low 100s F (high 30s C), according to AccuWeather.com.

Edison International's Southern California Edison utility said its transmission system was performing well but the continuing multi-day heat wave and lighting caused some isolated equipment failures and scattered outages.

As the heat continues, the utility warned it was possible other equipment might fail because of the high ongoing usage.

The California Independent System Operator, which operates much of the state's power grid, forecast demand this week, would not top the all-time usage record of more than 50,000 megawatts. The ISO forecast demand would reach about 44,400 MW on Monday and 45,200 MW on Tuesday.

While saying it expects to have sufficient resources to meet demand this week and throughout the summer, Southern California Edison noted conservation could provide an added reserve should an unexpected power emergency occur.

Unexpected emergencies could include mechanical problems affecting a major power plant or wildfires shutting down a major transmission system.

Southern California should see some relief Wednesday when high temperatures fall to the low 80s F (mid-20s C), AccuWeather.com forecast.

Edison International, of Rosemead, California, owns and operates about 14,000 MW of generating capacity, markets energy commodities in North America, and transmits and distributes electricity to about 4.9 million customers in central and Southern California.

(Reporting by Scott DiSavino; Editing by Lisa Shumaker)