Why Norway’s Wireless Taxis Are the "Holy Grail" of Electric Car Charging

Oslo is set to become the first city in the world to offer wireless charging for its electric taxis. The pilot project, announced Thursday, will see the Norwegian city retrofit around 20 to 25 taxis with hardware capable of receiving 75 kilowatts of power while waiting at the stand. The city plans to make all of its taxis emissions-free by 2023.

“For this type of setup, taxis waiting in a taxi queue, they stop and start, just move forward in the queue without plugging in and plugging out…it lowers the user barrier to transition to electric vehicles,” Ole Gudbrann Hempel, head of Fortum’s public charging network in Norway, the clean energy firm organizing the project, tells Inverse. “I think this is a perfect example of how we can utilize this technology.”

Cutting the cord could take the electric car to the next level. It’s an idea that Ford and General Motors have explored, and electric buses in Sweden and South Korea have benefitted from the option. Hempel sees little benefit for standard passenger cars as drivers need to stretch their legs for short breaks anyway — although he adds that “anything can change.” For taxis, and possibly semi trucks that would otherwise require unwieldy cable setups, wireless charging could be the way forward.

Finland-based Fortum is working with the city of Oslo, who will own the final project, to bring the technology to taxi fleets. The team is also working with American firm Momentum Dynamics, which has developed the inductive charging system. The goal is to work with a car company and retrofit their vehicles, meaning taxi drivers will have to buy one specific vehicle to use the service. Fortum is inviting manufacturers to start discussions and join the project.

“We can retrofit this on any car, any EV actually, even Tesla,” Hempel says. “The equipment itself doesn’t use that much space.”

The project plans to use OCPP, the open charge point protocol, to help the charger communicate with the backend system through an open standard. The project then adds some extra technologies to make it suitable for wireless use. It uses Near Field Communication to authenticate and match the car to the payment account, a process partly handled by Fortum’s system and partly by other proprietary technology.

“There are, quite frankly, a lot of protocols missing to cover everything that’s being done,” Hempel says. “They have been forced to take some proprietary measures to actually realize it.”

It then completes an alignment process to ensure the car is properly placed, which Hempel says has a tolerance level of around 20 percent. When the driver presses “park,” the charger will start within one second. This is a lot faster than standard wired chargers as there’s no need for isolation, as the air acts as the isolator. The charger itself is 96 percent energy efficient, three percentage points higher than a cable charger, meaning users get lots of energy at rapid speed.

“We in Fortum are endlessly focused on improving the user experience of charging their cars,” Hempel says. “So this is like a real holy grail for us that you don’t do anything.”

Pricing is yet to be determined, although Hempel says it will cost less than other city chargers. Pricing around the city is around 2.50 kroner ($0.29) per minute, so at a charge rate of 50 kilowatts, that results in three kroner ($0.35) per kilowatt-hour. Fortum won’t charge by the minute as taxi drivers have a natural incentive to leave the line, instead by kilowatt-hour. The team is targeting a price below these figures.

Although the team faces a number of challenges, like ensuring there’s enough power from the grid and ensuring it can get a manufacturer on board, initial signs are looking good for its success. The team already has 24 participants signed up, ready and willing to test the new technology. All will become clear when the first site goes live, expected to occur in August this year.