Our Incredibly Exciting Future With Wireless Self-Driving Cars

Jim Motavalli

Jim Motavalli | Mar 01, 2018

Is there wireless charging in your future? Imagine your self-driving electric car leaving you at the front door, then putting itself away in the garage. No need to plug it in because the car centers itself over the charging pad in the floor, and it’s got all its range back when you summon it in the morning.

It's simple enough. Park your BMW over that pad and the car starts charging automatically. (BMW photo)

It’s easy to see this scenario as decades away, because the U.S. plug-in market share is hovering between one and two percent of new car sales right now (five percent in California). But don’t expect the low numbers to continue forever. Automakers such as Volvo are preparing to electrify their whole fleets, and they’re going to be making them cheaper, with better range, and sparkling performance to prove that Tesla’s Model S is no fluke. Meanwhile, the autonomy race is heating up rapidly.

To really succeed, EVs have to be no-brainers for customers. According to Alex Gruzen, CEO of wireless charging supplier WiTricity, plugging in is a hang-up for some would-be converts. “It’s a bit of a barrier,” he said. “People have to make a fundamental shift from being reactive—my gas tank is near empty, better fill up—to being proactive—plugging in every night. If they can just park over a charging pad, they won’t have to worry about anything but bringing in the groceries.”

Mercedes shows how it all works. (Mercedes-Benz photo)

A bright wireless charging future has been predicted before, but hasn’t happened. The best we’ve been able to do is a charging pad for smart phones. What might be different now is that an 11-kilowatt global standard, SAE J2954, is being finalized. And that means, unlike the chaotic mix of international standards we have now for wired charging, all cars would have the same wireless system. If your parking space has a charging pad, any car—from a Hyundai to a Rolls-Royce—could pick up electrons there.

Gruzen—whose company has relationships with Nissan, General Motors and Toyota, plus a bunch of others he can’t name (some of them undoubtedly German)—says that wireless charging EVs will go wide in 2020. The first out of the gate this year will probably be BMW, which showed off a 530e iPerformance plug-in hybrid with a wireless charging pad at the Detroit show this year. Wireless takes slightly longer to charge the battery (3.5 hours) than wired (three hours) but it’s not a big difference.

Porsche's Mission E is said to have 310-mile range, and reaching 60 mph will take less than 3.5 seconds. (Porsche photo)

Right behind BMW is Porsche, which will wirelessly charge its Tesla-challenging and super-fast 2019 Mission E. The 11-kilowatt system is via a Dutch company named ProDrive. WiTricity is a partner in that enterprise. Mercedes-Benz worked with BMW and Qualcomm on wireless charging, and its system (limited to 3.6 kilowatts initially, but 11 kilowatts later) is being deployed this year. The Germans would appear to be in the lead.

In Gruzen’s vision, EVs will charge wirelessly at home (80 percent of the time) and work (10 percent) and then plug in for 480-volt fast charging (80 percent charged in half an hour) on highways.

Automakers are showing off the latest in wireless charging tech at auto shows. (Mercedes-Benz photo)

WiTricity’s magnetic resonance technology doesn’t require that the car be precisely positioned over the charging pad, which means it won’t need to be autonomously aligned. As the BMW video below indicates, the driver will be guided by some blue lines that will appear on the screen, which is kind of how backup cameras work now.

Yes, wireless charging involves some loss—WiTricity’s Drive II evaluation system is “up to 94-percent efficient grid to battery.” But Gruzen counters that plug-in system have losses, too. “Wired charging is 88- to 95-percent efficient,” he said. “The best system is BMW’s and that’s 94.6-percent efficient.”

The public may or may not embrace wireless charging. A recent Green Car Reports/Twitter poll found 35 percent voting for “plugs are all you need,” but 45 percent choosing “wireless is a nice option” and 14 percent “wireless is the best!” For six percent, the technology will remain low volume.


Sam Abuelsamid, a senior analyst at Navigant Research, is dubious about the near future. “I’m dubious wireless charging will be much more than niche in 2020," he said. His colleague Lisa Jerram adds, "I do think WiTricity is doing all the things you need to do to get the technology to be commercially viable, but I think the value proposition for it is going to be limited in the beginning because of the higher cost. And the fact that most charging stations will still use conventional plugs. Over the long term, I could see a shift to wireless but there is a bit of a chicken-and-egg problem with it."

The tech could get delayed—it has before—but there seems little doubt that it’s coming, and it will be transformative. Other big wireless players, besides WiTricity and Qualcomm, are Momentum Dynamics and Wireless Advanced Vehicle Electrification (WAVE). A company called Plugless Power (a/k/a Evatran) will sell you aftermarket wireless chargers for cars like the Tesla Model S, Nissan Leaf and Chevy Volt.

 “What we could potentially see with the wireless power transfer is incredibly exciting,” Andrew Hoskinson, the EV Infrastructure Planning and Development Strategist at San Diego’s Center for Sustainable Energy, told the San Diego Union-Tribune. “You’re going to have a vehicle that is self-parking and after taking occupants wherever they needed to be dropped off, the vehicle immediately parks and beings to charge automatically,” said Hoskinson. “You end up with something that can be a real game-changer.”

In the real world, of course, things rarely go smoothly. I mentioned those in-car charging pads for smart phones earlier. Well, the Mercedes E300 has one of those, and the iPhone 8 or X are set up to use the tech. But drop the unit in the bin and the phone thinks you want to use Apple Pay and starts the app. Arrgh. It pauses your music, too. They’ll fix it, though, of course they will.  

Here, on video, is more about BMW's system:

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