Rolling blackouts are a ‘possibility’ amid California’s extreme heat wave, officials say

Gearing up for a sweltering heat wave that will push temperatures across large swaths of California into the triple digits, state officials are warning that Californians should brace for the possibility of rolling blackouts.

“It’s a possibility but not an inevitability,” Elliot Mainzer, president of the California Independent System Operator, said during a news briefing Wednesday afternoon. “It’s tight grid conditions but if we all pitch in that will reduce the likelihood of rotating outages.”

A prolonged heat wave is expected to begin Wednesday and last for nearly a week across the West coast, including the majority of the Golden State. High temperatures across California are expected to be 10-20 degrees warmer than normal, with the most torrid conditions sweeping across the state on Sunday and Monday.

The extreme heat event — bringing record temperatures to the region during the Labor Day holiday weekend — marks the biggest challenge for California’s electricity grid since August 2020, the last time portions of the state were hit with rolling outages.

In hopes of avoiding a similar situation this weekend, California’s electricity grid operator on Wednesday issued the first of what is expected to be a series of Flex alerts through the Labor Day and warned that it was wrestling with an expected electrical power shortage. The agency later extended the advisory for Thursday as well.

Under the Flex alert, the California Independent System Operator urges Californians to limit their power consumption during peak hours of 4-9 p.m. by turning off unnecessary lights, avoiding the use of large appliances and setting thermostats at or above 78 degrees.

Gov. Gavin Newsom also proclaimed a State of Emergency on Wednesday that allows the state to take temporary measures to increase energy production and reduce demand amid the extreme heat wave. The proclamation allows power plants to generate additional electricity, permits use of backup generators and allows ships in California ports to reduce their consumption of electricity from the grid.

“The reality is we’re living in an era of extreme — extreme heat, extreme drought, extreme flooding,” Newsom said during a briefing. “Let’s work together with the sense of purpose that we often always do to meet this challenge.”

In Sacramento, temperatures could reach as high as 114 degrees on Monday, according to the National Weather Service. Forecasters are expecting to see a slew of records broken: for all-time highest daily temperatures on Sunday and Monday, record high for September and most days in a year with temperatures over 100 degrees.

“It’s turning into quite an impactful event, especially because it falls on a holiday weekend when a lot of people are traditionally spending time outside,” said Katrina Hand, a forecaster for the National Weather Service in Sacramento.

State officials are advising residents to stay hydrated and avoid spending time outside during the afternoon hours when the heat will be the most intense.

“It’s not just the sensitive people who are going to be at risk,” Hand said. “Even healthy people need to take precautions to stay safe in this heat.”

The heat wave and the governor’s proclamation come as California legislatures are debating a series of Newsom’s aggressive climate proposals, including a plan to temporarily halt the closure of the state’s last nuclear power plant, Diablo Canyon.

Despite opposition from environmental groups and some progressive Democrats, Newsom said Wednesday that extending the plant’s life beyond 2025 will help prevent future widespread power outages.

Energy from the Diablo Canyon plant does not produce greenhouse gases, he added, and extending the life of the plant will play an instrumental role in building the state’s green energy future.

“This is critical in the context of making sure we have energy reliability going forward,” Newsom said. “... That energy provides baseload and reliability and affordability that will complement and allow us to stack all of the green energy that we’re bringing online at record rates.”