SAN FRANCISCO, Calif. (KRON) — PG&E has been directed by the California Independent System Operator (ISO) to begin shutting off power as CAISO has declared a statewide Stage 3 Emergency due to excessive heat driving up electricity use and putting strain on the grid.

The power outages will affect about 200,000 to 250,000 customers at a time in rotating power outages.

Other utilities in California are being directed to take similar actions.

The power will be turned off in rotating blocks until about 11 p.m. Power could be out for about one hour for each block.

42,455 Sonoma County residents are expected to be impacted by blackouts.

As of 9:04 p.m., PG&E says no more outages are planned for Friday night. Crews are working to restore power to those customers who were affected by the shutoffs.

Full restoration is expected by 11 p.m.

Photo: CAISO website

Due to the emergency, PG&E will be unable to notify customers in advance of the power shutoffs, which could occur anywhere within PG&E’s service area.

“The safety of our customers and the communities that we serve is PG&E’s most important responsibility. We urge our customers to take immediate steps to reduce their power usage. We will work to restore power safely and as quickly as we are able,” Michael Lewis, Interim President of PG&E, said.

On Thursday, the ISO issued a Flex Alert for Friday from 3 p.m. to 10 p.m., calling on the public to conserve electricity.

Consumers are being asked to set air conditioner thermostats to 78 degrees or higher, turn off unnecessary lights and put off using major appliances during the time.

Below is a list of power outages across the Bay Area:

  • SAN RAFAEL: 35,207 CUSTOMERS — TIME RESTORED 9:45 PM
  • VALLEJO/AMERICAN CANYON: 22,113 CUSTOMERS — TIME RESTORED 9:30 PM
  • MOUNTAIN VIEW/LOS ALTOS: 1,348 CUSTOMERS — TIME RESTORED 9:15
  • SAN MATEO/FOSTER CITY: 33,868 CUSTOMERS — TIME RESTORED 9 pm
  • BELMONT: 1,423 CUSTOMERS — TIME RESTORED 9:15 PM
  • HILLSBOROUGH: 411 CUSTOMERS — TIME RESTORED 11:59 PM
  • MILPITAS: 634 CUSTOMERS, TIME RESTORED N/A
  • CLAYTON: 1,202 CUSTOMERS, TIME RESTORED N/A
  • CONCORD: 719 CUSTOMERS, TIME RESTORED N/A
  • VALLEJO: 2,555 CUSTOMERS, TIME RESTORED 9:30 PM
  • LAS GALLINAS (MARIN COUNTY): 9,146 CUSTOMERS TIME RESTORED 10 PM
  • ROHNERT PARK/COTATI: 6,579 CUSTOMERS — TIME RESTORED 10:15 PM

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