Electric-drive vehicles, whether powered by batteries, fuel cells, or gasoline hybrids, have within them the energy source and power electronics capable of producing the 60 Hz AC electricity that powers homes and offices.
When connections are added to allow this electricity to flow from cars to power lines, we call it "vehicle to grid" power, or V2G.
Cars pack a lot of power. One typical electric-drive vehicle can put out over 10kW, the average draw of 10 houses. The key to realizing economic value from V2G is precise timing of its grid power production to fit within driving requirments while meeting the time-critical power "dispatch" of the electric distribution system.
On September 21, 2009, Delaware passed a law that requires electric utilities to compensate owners of electric cars for electricity sent back to the grid at the same rate they pay for electricity to charge the battery.
AutoPort Inc. near the Port of Wilmington, has produced the first electric car built in Delaware, and the first car ever manufactured with complete V2G controls built-in from the factory.
www.udel.edu/V2G/
en.wikipedia.org/wiki/Vehicle-to-grid