California utilities are preparing homes and businesses for what could be a 1,700-MW power shortage during peak demand hours this summer if another heat wave grips the Western U.S. as expected.

After state officials warned May 6 that a power supply shortage could force temporary blackouts, California utilities have been stepping up outreach to customers to remind them of energy conservation programs the utilities hope will stretch the grid further.

The power companies are also rushing to secure additional wholesale power above what weather and demand forecasts would normally require and are expanding energy storage facilities.

While the state's overall energy capacity continues to grow, "the grid remains vulnerable to heat throughout the West," Jeffrey Monford, a spokesperson for Southern California Edison Co., said in an interview. "It's also vulnerable to project development risk because of drought conditions and tight supplies for battery storage."

A power shortage forced rolling blackouts in the state during an August 2020 heat wave. Pacific Gas and Electric Co. said it has since secured additional energy contracts, expanded demand response and other conservation programs, and sought to keep more water in reservoirs so more hydropower would be available during the hot summer months.

"We believe the grid is better prepared than it was last year and the previous year to meet peak loads," PG&E spokesperson Lynsey Paulo said in an email. "We are working with [state agencies] to ensure a safe and reliable electric service this summer."

Another 1,800 MW needed by 2025

After a spring that was warmer than normal, California is projected to experience above-normal temperatures and less rainfall than usual between May and August. The NOAA Climate Prediction Center shows above-normal temperatures throughout the Western U.S. for the summer months, adding to the concern over regional grid resources.

By summer 2025, California will need to secure another 1,800 MW of energy to avoid an even larger shortfall, state energy officials said. Along with higher costs associated with wildfire mitigation and rising transmission rates, the state's energy challenges will also increase bundled residential power bills by more than 10% annually, officials said.

California Gov. Gavin Newsom recently suggested the state may seek to delay the closure of PG&E's 2,240-MW Diablo Canyon nuclear plant to secure enough grid resources. The plant is scheduled to shut down in 2025.

California is facing multiple challenges due to rising temperatures and drought fueled by climate change, including newly imposed water restrictions caused by low flows in the Colorado River and low winter runoff from the northern part of the state.

In late April, Southern California declared a first-of-a-kind water shortage, restricting outdoor watering to one day a week in portions of Los Angeles, San Bernardino and Ventura counties, home to millions of people.

"We are facing unprecedented reductions in our Northern California supplies, and we have to respond with unprecedented measures," Adel Hagekhalil, general manager of the Metropolitan Water District of Southern California, said in an April 27 statement. "We're adapting to climate change in real time."

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