Vehicle-to-grid (V2G) system

Vehicle-to-grid (V2G) describes a system in which plug-in electric vehicles, such as electric cars (BEVs) and plug-in hybrids (PHEVs), communicate with the power grid to sell demand response services by either delivering electricity into the grid or by throttling their charging rate.[1][2]

Vehicle-to-grid can be used with such gridable vehicles, that is, plug-in electric vehicles (BEVs and PHEVs), with grid capacity. Since most vehicles are parked an average of 95 percent of the time, their batteries could be used to let electricity flow from the car to the power lines and back, with a value to the utilities of up to $4,000 per year per car.
BMW, Continental, Daimler, Fraunhofer, RWE, Siemens, TU Dortmund and VW – the partners in the new research project “eNterop” belong to the German industrial and research scene’s elite. They are now working with domestic proponents of international standardization of “vehicle-to-grid communication” (V2G) for electric vehicle networks on the next stage: an open test platform for the interface between electric vehicles and charging infrastructures. Their goal is the rapid establishment of standards for supply and communications systems between vehicles and electric power grids.

Electric vehicles will have to be able to communicate with grids reliably and charge or supply electricity at charging stations regardless of their make.

Sources:
http://www.iff.fraunhofer.de/en/press/press-releases/2013/electric-vehicles-network-standard.html
http://en.wikipedia.org/wiki/Vehicle-to-grid