What did the several hundred college students compete to build recently in Washington,DC?

Experts say in the near future, many houses in the United States will be powered by energy from the sun, Many people in Washington, D. C., recently were able to see what some of those homes might look like. Several hundred college students from across the country took part in a competition to see who could build the best solar-powered house. The United States Department of Energy organized the competition.
    Students from fourteen colleges and universities took part in this Solar Home Competition. Student teams competed in a series of ten contests to see who could design, build and operate the best house powered only by the sun. The solar homes were built on the National Mall, the grassy open area between the United States Capitol building and the Washington Monument. The solar houses were set up in the middle.
    Each team included at least twenty students of design, architecture and building sciences. The students gained the money to buy equipment and materials for their house. Each house cost as much as $250,000 to build.
    A solar-powered house has a roof designed to take in the heat of the sun and change it to energy, That power is then stored in a battery bank which supplies power to the whole house.
    As part of the competition, the teams were expected to spend most of the day in their homes doing normal activities. The activities used electricity powered by the sun. For example, the students cooked food, used computers, operated lights and washed clothes in Machines. They even drove around the solar village in electric cars powered by a solar battery.
    The competition is designed to show Americans that solar energy works, because the use of solar energy in the United States is less than in other parts of the world. Only about 20, 000 American homes are solar-powered.