PG&E customers across California have been asked to conserve electricity through Wednesday before the statewide heat wave peaks.
The California Independent System Operator, which oversees the operation of the state's bulk electric system, transmission lines and electricity market, on Monday issued a statewide Flex Alert, asking people to voluntarily cut down on utility consumption.
The goal is to save 500 megawatts to avoid widespread blackouts, the agency said. And that means everyone must pitch in. Electric customers are urged to conserve electricity from 2 p.m. to 9 p.m. Tuesday and Wednesday.
"We find that 500 megawatts shaved off is enough to get us over the critical time," said Anne Gonzales, a CAISO spokeswoman. "If consumers can respond, that will take a lot of the stress off of the grid."
Conservation is especially recommended during the late afternoon, when air conditioners are typically at peak use, officials said.
According to CAISO officials, electric customers can help avoid power outages by turning off all unnecessary lights, using major appliances before 2 p.m. or after 9 p.m., and setting air conditioners to 78 degrees or higher.
Temperatures are expected to soar Thursday, forcing the National Weather Service for the Bay Area to upgrade a heat advisory to an excessive heat warning for some of the hotter inland areas of the North Bay mountains and the East Bay valleys and hills.
The heat advisory has also been extended until Thursday evening for most inland areas and expanded to the San Francisco Bay shoreline, including Berkeley, Oakland, Fremont, Redwood City and San Mateo — but not San Francisco.
Coastal locations will be near normal, but inland weather is expected to be roughly 20 degrees hotter than usual.
Temperatures will rise an estimated two to five degrees from Tuesday to Wednesday, then another two to five degrees on Thursday — and some areas may exceed 110 degrees.
The weather will begin to cool off Friday, continuing into the weekend.