Electric vehicle (EV) charging has been under development for years now, but is inching closer to viability as Volvo Group Venture Capital, the investment wing of Volvo Group, invested in high-speed wireless charging vendor Momentum Dynamics Inc.

Momentum's technology uses inductive charging with a large pad and a magnetic coil under the bus for charging. Source: Momentum Dynamics

Momentum is developing inductive charging technologies for both the automotive and mass transportation industries for EVs and autonomous, connected buses and vans. Most recently, Momentum began a program in Wenatchee, Washington, for a fleet of battery-electric transit buses using a 200 kilowatt (kW) wireless charging system. Momentum is also conducting additional pilot projects in Europe and North America with cars, buses, trucks and trains.

Volvo isn’t the first automotive OEM to get behind wireless recharging. Both BMW and Daimler announced they plan to support the technology in the future, with Daimler working on a project called Plug and Charge with e-mobility vendor Hubject. Last year, Hyundai completed a three-year pilot project for a fast-charging, wireless power transfer system on Kia electric vehicles, which may lead to a system installed in future cars.

What is wireless charging?

Wireless charging connects to the power grid without any cables, wires or supervision. The technology is similar to wireless recharging with smartphones. Instead of a phone, the vehicle rests over a charging pad and electricity is induced through an air gap from a transmitting magnetic coil in the charger to a receiving magnetic coil outfitted under the car.

Instead of stopping an EV at a charging station or charging it overnight at home, wireless vehicle charging allows vehicles to charge in multiple locations, such as in a smart city or along routes for mass transit. The goal is to improve the efficiency and driving range of EVs with less recharging downtime. It would also reduce "range anxiety" for EV owners, as they would not need to stop to recharge mid-trip.

The ultimate goal of EV wireless recharging is to do it while the car is in motion, called dynamic charging. This would connect vehicles to the power grid and recharge them while driving. The DoE said this would be through durable power transfer coils on highways and streets at various intervals. The technology is not even in the early stages of development, but it could be the path toward reducing American's consumption of petroleum.

Looking ahead

The U.S. Department of Energy (DoE) said wireless EV charging could reduce harmful emissions by encouraging EV drivers to use the cars more often. Furthermore, most plug-in electric vehicles could be outfitted with an aftermarket wireless recharging system, the DoE said.

According to Lisa Jerram, principal research analyst at Navigant Research, wireless car charging will need to be widely available in locations where current plug-in options are found, such as hotels, workplaces and retail sites if it hopes to become the dominant technology on the market. But this requires charging site hosts to offer the technology, and there currently aren’t enough EVs for these companies to make the investment. More than likely, major deployment of the technology won’t happen until the mid-2020s, but the technology could see significant growth from 2025 onward, she added.