Wireless Charging for Electric Cars Is Nearly Useful

On the list of first-world problems, not being bothered to plug in your Tesla is very near the top. Luckily for lazy Model S owners, the Department of Energy is on it.

Wireless charging has been around for years in cellphones, but it’s never really caught on, due to its low efficiency, lack of universal compatibility, and occasional stupidity. But for cars, it makes a ton of sense: unlike phones, we tend to leave our cars in exactly the same space when we’re not actively using them.

Unfortunately, wireless charging for cars is more difficult than phones, due to the higher wattage necessary. The Department of Energy’s Oak Ridge National Laboratory has made a recent breakthrough on that front that shows promise, with a proof-of-concept 20kW charger working at 90 percent efficiency. That’s enough to put 60 miles of charge into a Tesla every hour, right on par with Tesla’s own home chargers.


Wireless charging isn’t ready for the prime time yet—the ORNL’s proof of concept is still just that—but it’s likely to be an important stepping stone for getting more people interested in electric vehicles.

Without major leaps in battery technology sometime soon, charging a battery is going to remain slower than filling a tank with gas, so anything that can make topping up an EV’s battery easier will be welcome. No-one’s going to bother plugging in a car while they run into a drug store, or wait in line at a drive-through, but wireless charging would do just that, without any effort from the driver.

There’s also autonomous cars to consider. A self-driving car than needs a human to plug it into the wall would be annoying, or require some Roomba-esque docking system. But with wireless chargers, autonomous cars would be free to roam and recharge as needed, all without human intervention. Even Skynet needs wheels sometimes.



Contributing Editor

Share This Story

Get our `newsletter`


20 kW for 60 minutes is 20kWh and 1kWh costs around $0.13, so twenty of them costs around $2.60 to drive around 60 miles. A bit less, actually because of the 90 percent efficiency. So call it 60 miles of driving for about $2.89. What an enormous saving over today’s Prius at 55 mpg and gas at about $2.06 according to the AAA.

I’m sorry. This was a Big Deal because why?