Energy officials in California, which banned the sale of new, gasoline-powered vehicles starting in 13 years, are asking residents there not to charge their electric vehicles during peak periods this holiday weekend because of extreme temperatures.

In a “heat bulletin” sent to customers across the state, the operators of California’s electric grid said rising temperatures beginning Wednesday and continuing through the Labor Day weekend will likely stress the grid to the point that customers can expect energy shortages and should be expected to help conserve electricity.

Among the conservation measures suggested by California ISO are setting household thermostats to 78 degrees, turning off unnecessary lights, and avoiding the use of large appliances or the charging of electric vehicles.

Temperatures across the western United States are expected to set records this weekend, with temperatures in northern California 10 to 20 degrees above normal and between 10 and 18 degrees above normal in southern California through Tuesday next week.

A Louisiana Republican congressman, Steve Scalise, who serves as the House whip, noted the irony of the warning coming just days after the announcement about the phase-out of gas-powered cars.

“California is now telling people to ‘avoid using large appliances and charging electric vehicles’ from 4-9pm. This from the same state that’s going to force everyone to buy electric cars by 2035,” Mr. Scalise wrote  in a post on Twitter Wednesday morning. “This is what Democrat control looks like — and they want it nationwide. What a joke.”

Last week, California’s Air Resources Board ruled that, beginning in 2035, the only new cars, trucks, and SUVs sold in the state will be zero-emission types such as electric vehicles. Used vehicles that rely on internal combustion engines will still be available.

The rules will be phased in over the next decade. Four years from now, the state wants 35 percent of all new vehicles to be powered by batteries or hydrogen. By 2030, 68 percent of all new vehicles must be zero-emission.

More than 16 percent of new cars sold in California in 2022 were zero-emission vehicles, up from 12 percent in 2021 and 8 percent in 2020.

Many environmental groups praised the move, but others said it did not go far enough, fast enough.

“This rule needed to match the urgency of the climate crisis and instead leaves Californians making sputtering progress in the slow lane,” an attorney at the Center for Biological Diversity, Scott Hochberg, said. “California needs to act strongly on gas-powered cars instead of ignoring them, and shift to EVs much sooner or watch our climate stability slip away.”

Others warned that the state’s electricity-generating capacity is nowhere near ready to handle the additional load required to charge all the batteries required in an all-electric, or even majority-electric, fleet.

The head of the Alliance for Automotive Innovation, an auto industry trade group, John Bozzella, said that even in California — the country’s leading electric vehicle marketplace — meeting the sale mandates announced by the state will be “extremely challenging.”

“Whether or not these requirements are realistic or achievable is directly linked to external factors like inflation, charging and fuel infrastructure, supply chains, labor, critical mineral availability and pricing, and the ongoing semiconductor shortage,” Mr. Bozzella said. “These are complex, intertwined, and global issues well beyond the control” of either the California Air Resource Board or the auto industry.