This is a really great thing to go to. The goal:
The U.S. Department of Energy Solar Decathlon challenges collegiate teams to design, build, and operate solar-powered houses that are cost-effective, energy-efficient, and attractive. The winner of the competition is the team that best blends affordability, consumer appeal, and design excellence with optimal energy production and maximum efficiency.
The winner this year was the University of Maryland:
A green home designed and built by University of Maryland students took top overall honors in this year’s U.S. Energy Department Solar Decathlon, which aims to showcase innovative and affordable solar-powered homes.
U-Md.’s winning home, WaterShed, was inspired by the Chesapeake Bay ecosystem. It features a green roof that provides insulation and a system that filters sink and shower water, recyling it for use in wetland gardens that run the length of the house.
Here's a link for more information on the house.
Here are some pictures from the competition.