Researchers are working on a concept where electric cars would be charged by electrical wiring embedded in roadways. This way electric cars would be charged up while driving, giving the cars a longer effective driving range.

The basic idea is to transmit electricity wirelessly from the road to cars driving by. Wireless transmission of electricity is done in some cases such as the wireless charging units for cellphones, or the inductive charging for electric toothbrushes. In electric cars some of the earlier ones, such as the EV1, used inductive charging connectors.

Generally speaking transmitting electricity loses efficiency the greater the distance it is transmitted. Also generally speaking the process involves an efficiency loss, unlike transporting electricity through a copper cable where the efficiency is extremely high.

Research projects

Stanford's Center for Automotive Research at Stanford (CARS)

Wireless energy transfer with the presence of metallic planes - Wireless power could revolutionize highway transportation, Stanford researchers say - A group of researchers developed theoretical proof that power could be transmitted wirelessly from road to car with up to 97% efficiency. If the system could work in practice (rather than in theory) building electric roads to wirelessly power electric cars. But it would be very expensive, wouldn't it? http://www.torquenews.com/1075/maybe-future-electric-cars-will-be-charged-wirelessly-while-driving