SDG&E CEO Caroline Winn with Elliott Mainzer of the California ISO tour the utility’s battery storage facility in Miramar. Photo by Chris Jennewein

The head of California’s electric grid said Wednesday he is “guardedly optimistic” that the state will avoid rotating blackouts this summer, but warned that voluntary cooperation during Flex Alerts will be necessary.

Elliot Mainzer, president and CEO of the California Independent System Operator, said utilities throughout the state have built up power reserves and invested in new technology like battery storage to prevent blackouts like the ones in 2020.

But recent record heat in California and the Pacific Northwest combined with a drought that will reduce hydropower give him cause for concern.

“We’re adding just a little more ‘guarded’ to that guarded optimism,” he said, adding that Californians will likely be asked to conserve “a handful” of times over the summer.

Mainzer was in San Diego to tour San Diego Gas & Electric‘s new 30-megawatt lithium-ion battery backup facility in Miramar along with SDG&E CEO Caroline Winn.

That facility can supply the needs of 20,000 homes for four hours. It’s one of a growing number in San Diego and throughout the state that store solar energy created during the day for use during the peak 4 p.m. to 9 p.m. period.

Winn said the new backup facility is part of the extensive preparations made by SDG&E to be ready for the summer. Right now the utility has over 130 megawatts of additional capacity to handle a surge in demand.

“We have done everything in our power to ensure that the lights stay one,” she said, but warned that problems elsewhere in California or the West could affect SDG&E customers.

Mainzer estimated that California has 1,000 megawatts of battery storage right now, and will have 2,000 by the end of the summer and 5,000 — 10% of grid’s total capacity –in a few years as the technology improves. He praised SDG&E’s leadership in storage, which he said is key to a transition to clean energy.

“California has taken on a very ambitious goal of de-carbonizing its power system,” he said

Chris Jennewein

Chris Jennewein is Editor & Publisher of Times of San Diego.