Is overnight EV charging going to get more expensive?

For those who have the option, overnight charging is a big sell for electric vehicles. No need to plan a trip into town to fill up when your car is running low — just head out to the garage and plug it in. And it’s cheap, since electricity prices are low at night. For now.

A new study from Stanford University has found that peak net electricity demand could increase by 25 percent by 2035 due to increased adoption of electric vehicles. And since demand determines prices, that means the cost of plugging in your EV at night will go up accordingly. The study found that in a “stress test” scenario in which all vehicles currently on the road were EVs, nighttime charging demand could go up by as much as 50 percent. Yikes!

The authors of the study recommend better investment in daytime charging in order to prevent this scenario, like charging at work or other public locations. But, as we’ve been hearing a lot lately, that means the U.S. needs to ramp up its investment in public charging infrastructure, which is still lacking.

“Shifting drivers from home to daytime charging improves all metrics of grid impact including ramping, use of non-fossil fuel generation, storage requirements, and emissions. This insight is robust across varying levels of EV adoption,” the study says.