State officials say Detroit is getting the nation's first wireless system to charge electric vehicles on the road, while they drive. Officials say they hope the one-mile long pilot project will showcase the technology.
Wireless EV charging uses induction, via coils embedded in the road, to create an electromagnetic field. The electricity is transferred to the car's battery through a special receiver, so the car doesn't have to be plugged in to be charged.
Sam Abuelsamid is an EV technology expert and associate director of transportation with Guidehouse Insights.
He said he sees some practical uses for wireless charging for stationary electric vehicles, like parking lots and parking structures, as well as charging pads on routes used by electric delivery vehicles and buses.
But the technology may be impractical for vehicles traveling some distance on roadways, Abuelsamid said.
"Building this stuff into roadways is going to add a substantial amount of cost to the road infrastructure," he said. "We have a hard enough time paying for just normal pavement."
In addition, it's challenging to get a good charge between a moving vehicle and a roadway with wireless EV charging technology, Abuelsamid said.
"With a cable that's plugged in, you're talking roughly 96% efficiency, so 96% of the energy is getting into the battery," he said. "With induction charging, it's usually 90% efficiency, and it's optimized for when the electromagnetic field and the receiver on the vehicle are perfectly aligned. When they get out of alignment, that efficiency starts to drop off pretty quickly."
A nearly $2 million dollar grant from the Michigan Department of Transportation is helping to fund the project.