Electric vehicle charging needs to shift to daytime, study says: Here's why

"We need more capacity in the grid to support that charging."

Friday, September 23, 2022

Electric vehicle charging needs to shift to daytime, study says

A new study from Stanford says the best time to charge electric vehicles should be in the daytime, not nighttime, to help the electric grid.

SAN JOSE, Calif. (KGO) -- The best time of day to charge electric vehicles was just explored in a Stanford study.

The results even surprise the study's authors, but that's not all they explored when it came to electric vehicles. Experts say the habits we've developed with them should change.

The deadline to ban sales of new gas powered cars is looming.

Though the goal is for the ban to start in 2035, researchers say attention has to be paid to the electric grid.

"We need more capacity in the grid to support that charging," said Ram Rajagopalm, Stanford Professor and one of the authors on this Stanford study.

The mayors of Oakland and San Jose are speaking out on in favor of Proposition 30, a EV ballot measure opposed by Gov. Newsom.

It focuses on charging infrastructure access and the impacts on the already stressed - electric grid as more electric vehicles are adopted.

They found that if a third of homes in a neighborhood have electric vehicles and they all charge their cars at 11 p.m. the local grid could become unstable.

"It was a surprise for us, you know, that this daytime charging can make a significant difference," said Prof. Rajagopal.

But charging vehicles during the day from work or other shared charging infrastructures could help.

By 2035, the electric grid will be able to tap into more solar power, meaning in the morning and early afternoon, there's additional energy.

"What happens in those times, the days that you have additional power that, you know, could be curtailed, because there was no use for it," he said.

But one main problem with that now is the lack of financial incentive. Right now, electricity rates are cheaper in the evening hours.

The authors behind the study say policy makers need to take action to bring on better rates during the day.

"That also means making that type of charging accessible. Not everybody has access to a charger in the workplace," he said. "There is folks who have small businesses in low and middle income communities that may not have a charger that they could use for their business, and that will be a daytime charge."

ABC7 News reached out to the California Energy Commission, who helped fund the study, to find out what work is being done to bring on rates that would encourage people to charge during the daytime.

They said in part "State agencies are coordinating to develop and deploy rates, programs, and technologies that better align EV charging with grid conditions."

For Rajagopal's part, he's encouraged that by the time 2035 rolls around...the incentives will be there.

"I'm very positive that that we are in a very good trajectory, and things are lining up well," he said.