Seeding solar homes of the future

The Solar Decathlon, in which 20 universities build a solar-powered home, is a showcase for energy-efficient and solar technologies--some of which are available now, while others are invented for the event. Andy Karsner, the U.S. assistant secretary for energy efficiency and renewable energy, says the competition is a way to educate both students competing in the event and the general public who can see the modular houses on the National Mall in Washington.