Climate change ramped up its attacks on California this year, serving up massive wildfires and blistering heat waves, which led to widespread power outages. To fight back, Governor Gavin Newsom took aim at heat-trapping carbon pollution from cars. In September, he signed an order to phase out the sale of new gas-powered cars in California by 2035.
The move earned praise from green groups, but critics say that millions of new electric vehicles will further strain California’s power grid, which is already buckling under the stress of worsening heat waves. In a letter to Governor Newsom, outgoing EPA chief Andrew Wheeler asked how California can expect to service a massive fleet of EVs when it “can’t even keep the lights on today.”
In their response to Wheeler, California environmental officials said that electric cars “support a more reliable, resilient, and affordable grid. Indeed, electric transportation and increasingly cleaner electricity go hand-in-hand.”
On this point, experts agree. They say that EVs can charge up when demand is low, making use of surplus wind or solar power that might otherwise go unused, and they can unplug when demand peaks. In the future, EVs could even sell electricity back to the grid when needed, helping to prevent blackouts when the grid is overwhelmed, such as during a heat wave.
Today’s more sophisticated EV chargers can fuel cars when power is most abundant and prices are lowest. Drivers can set their cars to juice up overnight, for instance, after most people have gone to bed and the grid is flush with cheap power. This helps make sure that EVs don’t overload the grid when demand surges, usually in the late afternoon or early evening. Some chargers allow drivers to fuel up only when power falls below a specified price.
“You would want to plan to have your electric vehicles charging overnight or in the early hours of the morning when air-conditioning isn’t peaking on the system,” said Samantha Houston, a vehicles analyst at the Union of Concerned Scientists.
In the future, EVs will have a two-way relationship with the grid. Some EVs are already able to provide electricity. In Japan, the Nissan LEAF can supply backup electricity in an emergency—enough to power a home for two to four days. Someday, EVs will be able to sell electricity to the grid.