Volvo have been working on a way to supply constant electric power to large EV goods vehicles.
Last year they built a 400 metre long section of track at their test facility. The system works by having two power lines in the surface of the road, a current connector is in contact with the road at all times. This means that instead of relying on batteries the whole way, the road powers the vehicle, saving the batteries for town journeys.
Vehicles have to be travelling above 37 MPH to make the circuit live, to do this the vehicle is equipped with a radio emitter to make sure only the section its travelling over is energized at that particular moment.
It seems a very interesting idea, and something we have wondered if anyone would ever seriously pick up on. Im not sure on the whole “current collector” induction charging would be a far better method, but the energy required for that would be far greater!