LOS ANGELES (AP) – State officials are calling on residents to voluntarily conserve electricity during California’s heat wave, as demand on the power grid surges.

California’s Independent Supply Operator has issued a Flex Alert urging consumers to set thermostats to 78 degrees and reduce the use of appliances between 2 p.m. and 9 p.m. Wednesday.

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The alerts call for voluntary conservation so the state will not have to dip into energy reserves.

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Temperatures in the high 90s and 100s are predicted for California’s Central Valley, the Sacramento area and inland regions of the San Francisco Bay Area.

The heat wave is expected to extend into the holiday weekend.

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