Demand Saps State’s Electricity Reserves

Air conditioners worked overtime Friday, sapping California’s electricity reserves and pushing power officials to declare a moderate Stage 2 emergency.

California’s energy diet could become even stricter next week. The mounting heat wave is expected to continue through Wednesday and the ability to import electricity may be hampered by damage to transmission lines by wildfires in the West.

“We’re bracing for a very challenging day on Monday,” said Stephanie McCorkle, spokeswoman for the California Independent System Operator, which runs the electricity grid for about 75% of the state. All electricity users should do whatever they can to conserve power next week, she said.

(Customers of the Los Angeles Department of Water and Power--including Staples Center, where Democrats will convene next week--are not affected by the power shortage because the DWP system is separate from the Cal-ISO system and has more than enough electricity to meet demand.)

Californians used more electricity than expected Friday, reaching peak demand of 42,323 megawatts at 4:19 p.m. In Southern California Edison’s 50,000-square-mile territory, usage hit about 19,400 megawatts, just short of the record 19,935 megawatts set in August 1998.

Cal-ISO officials declared a Stage 2 emergency Friday afternoon when reserves fell below 5%. But they did not need to order the big investor-owned utilities to interrupt power to primarily commercial and industrial customers that had signed up for a program that reduces rates in exchange for the commitment to slash electricity use when supplies are tight.

“We have a heat wave building across the West,” McCorkle said. “We’re looking at fairly heavy loads Monday, Tuesday and Wednesday.”

Complicating the situation are wildfires in several Western states that are threatening or have damaged electricity transmission lines. Some lines are scheduled for repair over the weekend.

California’s power grid was pushed to the edge of meltdown Aug. 1 and 2 as demand outstripped supply. Demand has been growing by about 2% a year, but no major power plants have been built in the state in more than a decade.

If reserves were to fall below 1.5%, Cal-ISO would declare a Stage 3 emergency and rolling blackouts would become likely to avoid a more serious system collapse. California has yet to reach Stage 3, but rotating outages did hit the San Francisco Bay Area on June 14 because of local grid problems.