AC without Freeon

deseretnews.com | Teens win a cool $50,000 at international science fair

Two high school students took their physics class assignment and turned it into an award winning Freeon free car air conditioner. It uses the Peltier effect. "That's when current passes through dissimilar conductors connected to each other at two junctions, and one side heats up while the other stays cool." (uh, yea, that's the ticket). They bought the Peltier chips on Ebay for less than $10. The ac runs off electricity, which would increase gas mileage and increase horsepower. Another article on the topic says this about the cost and energy benefits:

Today, the young inventors say, U.S. drivers use about 7.9 billion gallons of fuel each year to run their air-conditioners, which draw power from the engine. By adopting their contraption - which taps into the electrical system, using fans to blow hot air through five Peltier chips and then releasing cold air - they say the country stands to save 3.9 billion gallons of fuel annually, or about $10 billion based on current gas prices.

Incredible

Via Innovation Blog