Wireless EV Charging Hits The Road

Wireless EV charging on-the-go is looking more real than ever before. That’s right, you’re charging as you drive, or better yet, while your car is driving you.

Over the last two years, researchers at University of Colorado have developed a proof of concept for wireless power transfer that transfers electrical energy through electric fields at very high frequencies.

Charging pads for electric vehicles are already a thing, and the US Department of Energy is eyeballing widespread use of charging pads for cars in about 10 years or so. The basic approach is to position a series of charging pads in the roadway, a few meters apart.

On a highway, you could have one lane dedicated to charging

A vehicle could simply travel in that lane when it needed an energy boost and could carry a smaller onboard battery as a result, reducing the overall cost of the vehicle.

To get their concept in motion, the team took the road less traveled so to speak. The conventional approach uses magnetic fields, which are easier to generate at scale than electric fields. The problem is:

However, magnetic fields travel in a looping pattern, requiring the use of fragile and lossy ferrites to keep the fields and the energy directed, resulting in an expensive system.

So, what did they do? Why, the increased the frequency of the electric fields, of course.

In his laboratory, researchers set up a series of metal plates parallel to one another, with a gap of 12 centimeters between. The bottom layer would be the transmitter embedded in the road, and the top layer would be a receiver in a vehicle:

When switched on, energy is transmitted from the bottom plates. Instantly, the lightbulb above the top plates lights up—power transmission with no wires needed. The device has steadily improved to the point where it can transmit kilowatts of power at megahertz-scale frequencies.

In the near term we envisions the technology being adapted for warehouse use. Automated warehouse robots and forklifts, for example, could move along areas enabled for wireless power transfer and never need to be plugged in, eliminating downtime and increasing productivity.

The technology could also be adapted for use in next-generation transportation projects like the Hyperloop, a proposed system that could take passengers from Los Angeles to San Francisco in 30 minutes.