From my friend Shai Agassi's blog ("The Long Tailpipe"):
"Electric cars and windmills are the most complementary products in the green world. Windmills generate a lot more energy at night, as wind picks up when the air cools down. Unfortunately, when you get a lot of wind most people are asleep and the electricity needs to be rerouted elsewhere. Cars are parked at night waiting to get electricity into the batteries - which is a perfect match to the electricity profile of wind generation.
Denmark has 20% of its generation capacity coming from wind. I learned that only 13% of the electrons though are wind electrons, the rest are sold to Norway and Germany - practically for free some times. Those 7% can drive every car in Denmark if you converted the fleet to Electric Vehicles. Clean, Cheap and Abundant - Electric Gasoline... "
Shai is starting a hugely ambitious project, called Better Place, to build an entire electric car infrastructure, starting in Israel. Oh, and the cars will be free--you'll pay for the electricity. (Picture taken in Denmark by Quin Garcia of the Better Place team).