California warns of blackouts as another hot summer looms

SACRAMENTO — Two years after the last wave of rolling blackouts, California officials said Friday the state could face potential shortfalls in electricity this summer as drought, extreme heat and wildfires pose threats to the fragile power grid.

Leaders of the Public Utilities Commission, the state’s Independent System Operator and the California Energy Commission said the state could face a shortage of as much as 1,700 megawatts — the equivalent of one major power plant — on the hottest days.

“We know reliability is going to be difficult,” said Alice Reynolds, president of the utilities commission, during a media briefing. “We know climate change is putting Californians at risk of further outages.”

Officials said California has made considerable progress in shoring up the grid, including the addition of nearly 4,000 megawatts of battery storage in just over two years. But climate change is creating ever-worsening heat waves, and supplies are tightening all over the West, making it harder for the state to import electricity in a pinch. Wildfires can knock transmission lines out of commission.

And the drought, entering its third year, is certain to erase several thousand megawatts of hydropower. Last summer, the

Department of Water Resources had to shut down the Lake Oroville hydro plant because reservoir levels got too low. It was the first closure of the plant since the reservoir opened in 1968.

A massive heat wave triggered two consecutive nights of rolling blackouts in August 2020, the

first such outages since the 2001 energy crisis, when supplies were being deliberately manipulated by energy suppliers. Since then state officials have scrambled to firm up supplies, directing the major utilities to increase their power-purchase efforts.

Nonetheless, energy reliability remains perilous as major heat waves trigger spikes in demand. The state narrowly avoided more blackouts last July, when temperatures soared past 110 degrees in much of California.

California’s increasing reliance on solar power and other forms of renewable energy has complicated its efforts to avoid blackouts. The state is at its most vulnerable from 6 to 9 p.m. in the summer, when solar power starts to fade but temperatures don’t.

“The temperatures are still high, the demand is relatively high,” said Mark Rothleder, senior vice president with the Independent System Operator, the quasi-governmental agency that runs the electricity grid.

That’s a major reason why the state is encouraging the development of battery farms — industrial-sized facilities that can store the unused solar power for use after the sun goes down.

The state has also postponed the planned shutdown of several high-polluting, gas-fired power plants on the Orange County coast. The plants are now scheduled to be retired at the end of 2023. But Ana Matosantos, Gov. Gavin Newsom’s Cabinet secretary, said the state is reevaluating those plans in an effort to maintain reliability.

Newsom recently told the Los Angeles Times that the state is also considering postponing the planned 2025 closure of PG&E Corp.’s Diablo Canyon nuclear plant near San Luis Obispo. Diablo Canyon, the last nuclear plant in California, has 2,280 megawatts of generating capacity.

“We can’t keep any options off the table,” Matosantos said.