Volvo's in-road electric charging system

The in-road electricity bug that's bitten researchers from Utah to South Korea has flown to Sweden, where Volvo is working with a handful of partners to develop its own take on dynamic, wireless recharging technology.

The Swedish automaker recently reported that it's been testing an in-road charging system near its Gothenburg headquarters since last fall. Volvo, along with Alstom, the Swedish Energy Agency, Swedish Transport Administration and a number of universities, has built a quarter-mile-long track for such testing, which includes a so-called "current collector" on the testing trucks.

Researchers have looked into the idea of in-road dynamic recharging as a way for vehicles to go long distances without requiring massive batteries. A touchless magnetic induction system was developed in South Korea as far back as 2009. And last year, Utah State researchers said they were working on a program that involved an electric bus being wirelessly charged by a mile-and-a-half long in-road recharging system powered by coils inside the road bed. Between this, fast charging and Tesla's battery swaps, solutions to long-distance EV driving are popping up everywhere.

Check out Volvo's press release below.
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The road of tomorrow is electric

Consider a future where trucks and buses continuously are supplied with electric power without carrying large batteries. Instead, power lines are built into the surface of the road. This could be a future solution for long-distance trucks and buses running on electricity.

The Volvo Group already has extensive knowledge about electric drivetrains, but in order to become world leading in sustainable transport solutions, the Volvo Group must find even more solutions that allow the vehicles to operate on renewable energy. A great deal of this energy will be distributed as electricity. However, the challenge is about supplying the vehicle with electricity power when needed.

"In city traffic, there are currently various solutions and we are researching many others. We have field tests in progress where our plug-in buses are equipped with a battery that can be charged quickly when the buses are at bus stops," says Mats Alaküla, the Volvo Group's expert on electric vehicles and Professor at Lund University.

But for long-distance trucks and buses, this will not work. They stop infrequently and to cope with this task they would need so many batteries that there would be no room for any loads or passengers. A solution is required where power is continuously supplied to the truck from an external source.

The Volvo Group participates in a large Swedish research project to find solutions for this, with the support of the Swedish Energy Agency. The project includes the Swedish Transport Administration, Vattenfall, several universities, vehicle manufacturers and suppliers.

The method currently being developed and tested by the Volvo Group, together with Alstom, entails two power lines built into the surface of the road along the entire length of the road. A current collector in contact with the power lines will be located on the truck.

"With this method, electric vehicles could be continuously supplied with power without carrying large batteries," says Mats Alaküla. "The power line will be built in sections and one section is only live as the truck passes."

Last year, Volvo built a 400-meter long track at its testing facility in Hällered outside Gothenburg. The company has been testing the system since last autumn.

"We are currently testing how to connect the electricity from the road to the truck. The electricity flows into a water-cooled heating element, with similar power requirement as an electricity-driven truck," says Richard Sebestyen, who is the project manager at Volvo Group Trucks Technology, which is the Volvo Group's research and development division.

However, a great deal of research still remains before this can become a reality. It involves the continued technical development of the current collector, electric motor and the control systems required. It also involves road construction, road maintenance, electricity supply along the roads and various payment models, etc.

"A lot of years remain before this is on our roads," says Mats Alaküla.

"But, if we are to succeed in creating sustainable transport systems, we must invest significantly in research now. I am convinced that we will find a cost-efficient way to supply electricity to vehicles in long-distance traffic and we have already come a long way in our research."