How future electric cars could recharge on the road

What if electric cars could recharge while you drive?

What if electric cars could recharge while speeding along the highway — freeing drivers to go greater and greater distances without having to stop and plug in?

Researchers are working on it. A team from Stanford University reported their latest advance in a research paper published Thursday in the journal Nature. In the paper, they share their progress towards developing new technology to wirelessly deliver electricity to moving objects — namely, electric vehicles. As the technology stands now, electric cars generally require hours in one place in order to charge.

In a preliminary experiment, the researchers transmitted electricity wirelessly to a moving LED lightbulb. The experiment was limited, involving only a one milliwatt charge, whereas electric cars tend to require tens of kilowatts of energy to function.

“In theory, one could drive for an unlimited amount of time without having to stop to recharge,” Shanhui Fan, senior author of the study and a professor of electrical engineering at Stanford University, said in a statement. “The hope is that you’ll be able to charge your electric car while you’re driving down the highway. A coil in the bottom of the vehicle could receive electricity from a series of coils connected to an electric current embedded in the road.”

The researchers further detailed their process in executing the so-called “mid-range wireless power transfer.” They said their method is more efficient thanks to a voltage amplifier and feedback resistor, which calibrate frequency without human assistance.

The team is now moving on to next steps: trying to dramatically increase the amount of energy that can be transferred, maximize the transfer distance, and boost efficiency in their process. The new research builds on a foundation already established by MIT researchers in 2007.

Bruce Belzowski, managing director of the Automotive Futures group at the University of Michigan Transportation Research Institute, called the paper “exciting” but said this particular vision would require a huge financial investment in new infrastructure.

Embedding electric currents in roads is easier said than done, Belzowski said.

“You’d have to thousands of vehicles like this to make this worth it,” Belzowski said. “The cost is extraordinary. Tearing up roads and putting this type of technology in roads would be extremely expensive.”

Still, Belzowski applauded the researchers’ effort in this area and encouraged further exploration beyond the research and development phase.

“I’d never put anything past an engineer or group of engineers or researchers to maybe find something,” he said.

The electric car market is rapidly evolving. Tesla Motors has said its upcoming Model 3 will go more than 200 miles on a single charge. The Chevy Bolt has an advertised range of 238 miles before charging is required.

In Norway, a slew of government incentives has brought the sticker price for electric cars lower than, at times, that of their gas or diesel equivalents. Perks of owning one include no highway tolls, free ferry rides and waived sales taxes. Under the Obama administration, federal regulations favored electric car manufacturers. In April, Tesla surpassed GM as the most valuable car maker in the U.S.

But new federal policies could dramatically undercut the momentum of electric cars, Belzowski said.

By backing away from regulations and incentives established under Mr. Obama, President Trump could “short-circuit” the electric car market, industry analysts have warned.

“I have a feeling there’s not going to be much of an incentive to move in that direction by the government,” Belzowski said. “Compared to China, which is giving out significant incentive to companies and buyers to try electric vehicles.”