Power grid officials ask public to cut electrical use due to heat

California energy officials are asking residents tempted to blast air conditioners during the heat wave Friday to cut back on electricity use.

The California Independent System Operator, which oversees 80 percent of the state’s electrical grid, issued a statewide alert for energy conservation from 1 p.m. to 10 p.m. Friday.

This June 10, 2009 file photo shows a compact fluorescent light bulb in Freeport, Maine. There are simple steps you may take to start conserving energy in your home, such as replacing your incandescent lighting in the room you use the most with energy efficient, fluorescent lighting. (AP Photo/Robert F. Bukaty, FILE) less This June 10, 2009 file photo shows a compact fluorescent light bulb in Freeport, Maine. There are simple steps you may take to start conserving energy in your home, such as replacing your incandescent lighting ... more Photo: Robert F. Bukaty, ASSOCIATED PRESS Photo: Robert F. Bukaty, ASSOCIATED PRESS Image 1 of / 34 Caption Close Power grid officials ask public to cut electrical use due to heat 1 / 34 Back to Gallery

Persistent hot temperatures puts added stress on the power grid, the company said. The alert comes as officials project a combination of limited power supply conditions and record demand.

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To prevent potential power outages, turn off unnecessary lights, set air conditioners to 78 degrees or higher, and avoid using major appliances between 1 p.m. and 10 p.m., officials said.

Jenna Lyons is a San Francisco Chronicle staff writer. Email: jlyons@sfchronicle.com Twitter: @JennaJourno