A working prototype of a plugless induction charger for electric and hybrid vehicles is in the works, according to physorg.com.

Virginia-based company Evatron demonstrated the system at the Plug In conference that took place the week of July 26 in San Jose, Calif.

To recharge a vehicle's battery using the system, the vehicle parks at a Plugless Power station over a floor-mounted parking block. The block automatically aligns itself with an adapter fitted to the vehicle and begins charging. No flow of electricity takes place between the vehicle and parking block, and no plugs or cables are used.

The system operates by electrical induction. In this process, electrical current flowing into a primary source produces a flow of current into a secondary source, without using plugs or cords.

The down side is that a 20-percent loss in power can take place during charging. Evatron rates its system at 80-percent efficient, but hopes to reach 90-percent efficiency by the time production units are released.

The system's first two major components are an adapter fitted on the vehicle and a parking block, which is a long flat pad on the ground underneath the vehicle at the charging station or in the garage. A control tower plugged into the grid is the third major component. Essentially, the adapter and parking block form two separated halves of an electrical transformer.

Induction chargers have been used in portable devices such as mobile phones and electric toothbrushes, and for medical implants, but this is the first time such a system has been tried for electric and hybrid vehicles.