The U.S. Department of Energy’s (DOE) third Solar Decathlon competition was held Oct. 12–20, 2007, on the National Mall in Washington, D.C. The Solar Decathlon consisted of 20 university teams—selected by DOE—competing on the National Mall to design, build and operate the most attractive and energy-efficient solar-powered home.

This year, teams were selected from the United States and Puerto Rico, Germany, Spain and Canada. For nine days, the National Mall was transformed into a showcase for cutting-edge solar and building technologies. For the previous two years, teams worked on the design, research, and testing necessary to construct and power the homes. Homes were shipped to Washington, D.C., and beginning Oct. 3, there will be a “solar village” on the National Mall.

The teams competed in 10 contests that test the ability to produce electricity and hot water from solar panels to perform all the functions of home—from turning on the lights to cooking, washing clothes and dishes, powering home electronics, and maintaining a comfortable temperature. These homes also must provide the power for an electric car.

In addition to the energy-related contests, each team was judged on its home’s architecture, livability and marketability (professional homebuilders evaluate the market concept for each home). The teams must provide documentation about their homes’ designs and communicate about their homes to the public.

Some contests were scored by measuring performance, and some were scored by juries representing expertise in appropriate fields. The decathlon’s prototype solar homes are zero-energy, yield zero carbon and included the latest high-tech solutions without sacrificing comfort, convenience and aesthetics. On Oct. 19., it was announced that Germany won the contest.

In 2002 and 2005, the Solar Decathlon drew more than 100,000 visitors to the National Mall. Visitors can tour the homes daily (except Wednesday, Oct. 17, when they are closed for judging). Or check out to learn more about competing teams and their solar houses.   EC