How the World's Fastest Electric Car Is Pushing Wireless Charging Tech
The record-breaking Drayson race car is inspiring research to power other devices wirelessly.
Image: Victoria Turk/Motherboard
With the first ever season of Formula E revving up in China next month, it's clear there's more to electric cars than Tesla. But the race cars hitting the track in Beijing don't have anything on the speed of Drayson Racing Technology's Lola B12 69/EV, which holds the record for the world's fastest lightweight electric car, and which uses the kind of power technologies that could one day have applications off the track too—like charging your phone wirelessly.
I checked out the Drayson racer at London's Science Museum, where it's making a brief pit stop to show off its charging capabilities. The car smashed the land speed record for lightweight electric cars last year with a top speed around 205 miles per hour, which is a damn sight faster than top Formula E car speeds of around 140mph.
"The whole idea of the project was to find out how fast an electric car can go if you use state-of-the-art, modern motorsport technology—so using the technology that's used in Formula One and Le Mans, but applying it to electric," Lord Drayson, a former government minister and the CEO of Drayson Racing, told me.
The car is admittedly a lot slower than the ThrustSSC, which holds the general land speed record at 763 miles per hour, but of course the Drayson car doesn't burn through five gallons of fuel a second. It also looks pleasingly like an actual race car, rather than a couple of jet engines with wheels.
Drayson explained that one of the major breakthroughs in developing the car was wireless power transfer—recharging the car without a cable. To get the land speed record you have to do two runs (one in each direction to cancel out the effects of wind) within an hour, and wireless charging helped juice it up quickly in between.
The team developed a charging system with Qualcomm that gets 20 kilowatts into the car with no contact. "That turned out to be really quite essential in terms of getting the world record," said Drayson. The system works via a pad on the floor that transfers charge to a receiving unit in the car parked over it.
But wireless power isn't only attractive for race cars, and this May Drayson formed a business with researchers out of Imperial College London to build on research into commercial wireless charging tech. "It's convinced us that this technology is going to be ubiquitous in the world," he said of the car project, and suggested that wireless power could one day be as prevalent as wireless data.
Paul Mitcheson, an electronics engineer at Imperial College London and the Power Electronics Centre who is working on charging innovations with Drayson Wireless, demonstrated how the tech could cross over to other devices. He exhibited a different, smaller-scale wireless power system that essentially consists of two vertically-oriented coils around the size of tabletop lamps.
He plugged one of the coil systems, the transmitter, into the mains, and it transferred power through the air to the other coil, the receiver. A second or so later, a lamp plugged into the receiver lit up. "This is different from the system in the car because the objective with this system is to make it as lightweight as possible," Mitcheson explained.
It essentially works like a transformer, through magnetic induction, but with the iron core removed. In this demonstration, Mitcheson said it was probably transferring around 30 watts of power over a 30cm air gap, with 80 percent efficiency, though the device is capable of 200 watts.
"We hope that this sort of technology eventually can make it into electric vehicles, but also applications like charging medical implants, or the ultimate vision of charging your phone while it's in your pocket," he said. That would require scaling the tech up and down, respectively.
Coming back to the car, one of the issues that has long dogged electric vehicles is the weight of the batteries required to keep the wheels turning. "The long term vision, really, is to get to the point where you can implant these wireless charging systems into the road and you could charge as you drive," said Mitcheson.
It's a long way off until regular motorways start charging your car as standard, but the idea of wireless electric vehicle charging is starting to creep into reality. Like the record Drayson car, Formula E cars (including one from Drayson Racing) will also use the Qualcomm wireless charging tech, called Halo. The car still has to park over the pad to charge, but it's a step on the way.
And far from the race tracks, even public transport is starting to take notice. On Wednesday, Transport for London announced it will trial wireless charging on some of its buses next year; up to four of its hybrid diesel-electric vehicles will be able to recharge their batteries while waiting at special bus stops, using tech provided by bus manufacturer Alexander Dennis.
Elon Musk isn't the only one helping make electric cars more palatable to the mainstream.