The California Independent System Operator issued a Flex Alert asking state residents to voluntarily conserve electricity Sunday and Monday as heat storms and wildfires cause power system failures.

The Flex Alert’s conservation period will begin at 3 p.m. and end at 10 p.m. on both days. To observe the alert, individuals and businesses should make an effort to turn off unnecessary appliances and lights, set their air conditioners to 78 degrees or higher and not use major appliances if possible, according to a press release from the office of California Gov. Gavin Newsom.

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