Parts of California and a handful of regions in other western states have seen record daily highs this week, with temperatures soaring up to 118 degrees.
The move – citing “extreme heat peril” – will ease restrictions on backup generators, auxiliary engines and other sources of carbon-powered electricity as the state braces for a sweltering weekend.
Newsom and state utility leaders were widely criticized during a heatwave last summer when more than 200,000 Californians suffered two days of rolling power outages – the first time residents had to deal with such issues in nearly 20 years.
Fuel consumption and air-quality restrictions on utility companies are also being rolled back during the emergency.
“The proclamation suspends certain permitting requirements, allowing the use of back-up power generation and freeing up additional energy capacity to help alleviate the heat-induced demands on the state’s energy grid,” the governor’s office said in a statement.
Officials are also urging Californians to try and reduce power consumption in the evenings until at least Friday.
Most of the order expires just before midnight Saturday, except for the exemptions for ships at port, which remain in effect until a minute to midnight Tuesday.
California’s main power grid operator issued a statewide “Flex Alert” earlier in the day, asking residents to do their best to conserve power by setting their thermostats above 78 degrees and avoiding using washers, dishwashers and other major appliances.
The National Weather Service warned of “dangerously hot, potentially life-threatening temperatures” through Saturday in the San Joaquin Valley.
A heat advisory was issued through Friday night for much of the San Francisco Bay Area, and several counties announced they were opening cooling centers.
The Associated Press contributed to this report.