Electric cars have huge batteries inside ... and as a demo of a converted Toyota Scion xB has just shown, one day you may be able to earn cash by selling spare electricity stored here back to the grid in times of shortage.
The vehicle was shown at annual meeting of the American Association for the Advancement of Science just yesterday, having been put together by researches keen to demonstrate the "vehicle to grid" or V2G concept. Essentially it doubles the car's utility in terms of environmental benefits: As well as reducing the burning of fossil fuels as gasoline, spare energy fed back to the grid in times of need from the car's battery reduces the need for extra energy to be found from burning coal, oil or gas in powerstations.
The technological enhancements required to make the system work are pretty minimal and will be familiar to followers of the Smart Grid. Essentially as well as being hooked up to the main electricity when it's being charged, the car also wires up via the powerline to the Internet, whereby it communicates with a server at the power company. When the grid is suffering an energy deficit, signals would be sent to the car and its smart connector--in fact to hosts of cars, all wired up across the area--and energy would flow back to the grid from the cars themselves. The upshot for the owner, of course, is that just like when you over-produce your own energy via solar panels or wind turbines, you can actually sell this power back to the electricity company.
The system would be much more complex when it rolls out for real public use, and the most important thing would be to install safeguards and intelligent power-management systems to ensure that no one's electric vehicle is overly drained. What use would an EV be if you hopped in it to go to work in the morning only to find it out of juice because it was cold last night and everyone's electric heating demanded too much power from the grid?