V2G

Vehicle-to-grid (V2G) describes a system in which plug-in electric vehicles, such as electric cars (BEV) and plug-in hybrids (PHEV), communicate with the power grid to sell demand response services by either returning electricity to the grid or by throttling their charging rate.

Vehicle-to-grid can be used with gridable vehicles, that is, plug-in electric vehicles (BEV and PHEV), with grid capacity. Since at any given time 95 percent of cars are parked, the batteries in electric vehicles could be used to let electricity flow from the car to the electric distribution network and back. This represents an estimated value to the utilities of up to $4,000 per year per car.

One notable V2G project in the United States is at the University of Delaware, where a V2G team headed by Dr. Willett Kempton has been conducting on-going research. An early operational implementation in Europe was conducted via the German government-funded MeRegioMobil project at the "KIT Smart Energy Home" of Karlsruhe Institute of Technology in cooperation with Opel as vehicle partner and utility EnBW providing grid expertise. Their goals are to educate the public about the environmental and economic benefits of V2G and enhance the product market. Other investigators are the Pacific Gas and Electric Company, Xcel Energy, the National Renewable Energy Laboratory, and, in the United Kingdom, the University of Warwick.

The company AC Propulsion Inc. coined the term V2G for vehicle-to-grid.

V2G is a version of battery-to-grid power applied to vehicles. There are three main different versions of the vehicle-to-grid concept, all of which involve an onboard battery:

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