A week or two ago PG&E did a showing of a Prius which had been modified so it provided what they call Vehicle-to-Grid use. This is an idea I've seen come around a few times, which I find rather nutty.
Last night I posted a blog entry, Vehicle-to-Grid is such a strange idea, why are people pursuing it?, referring to a couple articles on the subject which were inspired by PG&E's show. While they did the show in Sunnyvale, 10 minutes from my house, I didn't go.
In any case ... the idea stems from the hybrid cars, and fuel cell cars, have electrical generators on them. Some seem to think those generators can be harnessed to provide electrical generating capacity for peak usage hours. I think a critical problem in the electrical industry is the huge variance in electricity use between day and night, and there's a huge cost swing which you can only enjoy if you have time of use metering.
It just seems to be such a strange idea. I first heard of this with fuel cell cars .. reading the words of some spokesman saying something like When all the cars in the parking lot have hydrogen fuel cells, the corporate office can be powered by the cars the employees drive to work. Okay, sure, each fuel cell car has an electrical generator capable of producing 20 kilowatts or maybe more, and if you have a parking lot full of them that represents a tremendous electrical power plant sitting parked in the lot. But, really, if my driving range were based on the hydrogen in the car I'd be careful about expending that hydrogen. Right?
Getting "fuel" (whether it's gasoline, or hydrogen, or electricity) into a vehicle is a hurdle of sorts. Using that fuel for purposes other than driving decreases the range the vehicle can drive, and therefore increases the frequency per mile driven the driver has to stop to refuel.