Heat’s Grip Too Much for Southland Grid

The West’s deadly heat wave brought record temperatures and several power plant failures Thursday, triggering Southern California’s first electricity supply emergency in more than two years and hinting at problems the region could face on sweltering days this summer.

Blackouts were threatened for a few hours Thursday afternoon as air conditioners kicked into high gear -- setting power use records in the Southland -- but utility customers largely escaped disruptions. Although state utilities expect to have enough electricity to meet demand today, the prospect of continued hot and humid weather prompted California power officials to urge energy conservation to avoid shortages.

Across Western states, some 200 heat records have been broken in the last 10 days, according to the National Weather Service. In Phoenix, which hit 111 degrees Thursday, local authorities raised the heat-related death toll to 19. In Las Vegas, where there have been six deaths, the high of 109 degrees marked only the second day in the last week that the peak dipped below 115.

Two Los Angeles County temperature records were broken Thursday, said Stuart Seto, weather specialist for the National Weather Service. Woodland Hills posted 106 degrees Thursday, beating its old record of 104 in 1990, and Chatsworth posted 105 degrees, breaking its record of 103 degrees in 1988, he said.

People sought relief wherever they could. To beat the heat, about 100 young adults joined in a water balloon fight at the Jordan Downs housing development in Watts. Police and fire officials were called to the scene, where at least one bystander was injured in the frenzy, said Sgt. R.L. Johnson of the Los Angeles Police Department’s Southeast Division.

“Basically, whenever it gets hot, kids come out with water balloons,” Johnson said. “The Fire Department was bombarded with water balloons also, and of course they didn’t think that was funny.”

Power officials weren’t laughing either, as they struggled to keep a power shortage from escalating into blackouts.

The hot weather, combined with a rash of unplanned outages at power plants, strained electricity supplies and forced operators of the state’s electricity grid to declare a Stage 2 electricity emergency at 2:30 p.m. for the southern half of the state.

Under the three-stage emergency system, a Stage 2 means that utilities are within 5% of running out of electricity in the 75% of the state served by the California Independent System Operator, primarily the territories covered by Southern California Edison Co., San Diego Gas & Electric Co. and Pacific Gas & Electric Co.

“We have something we don’t have very often, and that’s high temperatures throughout the state, and we’re breaking records all over the place,” said Michael Shames, executive director of the Utility Consumers’ Action Network, a San Diego consumer group. “We don’t build [power plants] for the unusual, so whenever you get in record-breaking territory, you’re going to be in Stage 2.”

Power plants capable of generating more than 4,600 megawatts of electricity were out of service Thursday, including about 2,000 megawatts worth of unexpected outages in Southern California, Cal-ISO spokeswoman Stephanie McCorkle said. One megawatt is enough power to serve about 750 average homes.

Although there were scattered outages caused by equipment failures amid the heat, the region was spared from widespread intentional blackouts, in part because conservation plans kicked in to ease demand.

Corona, Norco and Pedley in Riverside County were among the communities hit by outages, with about 10,100 residences losing power for hours after lightning hit a 66,000-volt power line and burned out a transformer, said Ray Hicks, a spokesman for Southern California Edison.

The Eagle Rock and Highland Park areas of Los Angeles lost power around 1 p.m. because of a circuit problem, said Gale Harris, spokeswoman for the Los Angeles Department of Water and Power. Most of the 3,550 customers affected had their electricity restored by 3 p.m.

At Southern California Edison, the state’s second-largest power utility, electricity demand set a record for the second day in a row, peaking at 21,934 megawatts at 4 p.m.

In response to the Cal-ISO alert, the company sent radio signals to air conditioners in 157,461 homes, remotely turning them off temporarily as part of a voluntary curtailment program. The action can save as many as 338 megawatts of power, said Gil Alexander, spokesman for the Rosemead-based utility.

The DWP, which isn’t part of the Cal-ISO grid, reported that it delivered a record 5,661 megawatts of power to customers at the Thursday afternoon peak, beating a record of 5,643 megawatts set on Sept. 1, 1998. The DWP operates its own power plants and wasn’t affected by the constraints felt by other utilities.

Statewide on the territory served by Cal-ISO, demand soared to 44,651 megawatts, falling short of the previous record of 45,597 megawatts set Sept. 8, 2004.

State energy officials have warned for months that power supplies could run short on hot days. Power reserves would be particularly thin in Southern California, where demand is higher and where bottlenecks in transmission lines limit the amount of energy that can be imported from Arizona and Northern California, where supplies were projected to be relatively ample this summer.

Add in power plant failures or problems with high-voltage electricity lines, and blackouts could happen again for the first time since 2001, the height of the state’s energy crisis. Even though new plants have been steadily coming on line, electricity supplies remain tight because of fast-growing demand and the loss of older power generators that are being retired.

“The prognosis was that if things got to the point where it was a 1-in-10-year heat wave, then there was a prospect that they might have to interrupt some people,” said James Bushnell, research director at the University of California Energy Institute. If there are shortages, the cause “is going to be a combination of hot weather and some problems, which is what we’re sort of seeing now.”

If temperatures stay in the normal range for the rest of the summer, “things should be just fine,” Bushnell said. “The forecast said that we expected it to be tight, but we should scrape through.”

Times staff writers Wendy Lee and Nicholas Riccardi contributed to this report.