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A photo of a series of houses in various stages of completion, aligned along a path, with the U.S. Capitol building in the distance. Photo of a water tanker truck with a hose leading to the solar house. Eight people are lined up holding the hose, with one man on the top of the shed containing a storage tank.

Lawrence Technological University team members guide the hose leading from the water tanker to their house's storage tank.

Photo of a young woman with a hard hat working on wire frames that have green vines growing on them.

Elizabeth Conlan works with Cornell's green screens, planted with hops to commemorate Ithaca's fine beer industry.

An aerial view, looking down on one house under construction with piles of wood, panels, and other materials and equipment lying on the ground.

The New York Institute of Technology house, showing a typically busy and cluttered work site, as the teams rush to finish assembly of their houses.

Solar Decathlon 2007

Daily Journal - October 8, 2007

Day Six: Columbus Day

Today is Columbus Day, a national holiday in the United States celebrating the discovery of the new world in 1492. Five hundred and fifteen years later, here we are building a village that is going to define how we live in the new millennium. Christopher Columbus was a visionary for his time, but certainly electrical power and solar-powered houses were unknown to him. Columbus, however, was very adept at using the sun to power his sail boats, because solar radiation heats the atmosphere, which causes the winds to blow. So, I think it is fair to say that the new world was discovered with solar-powered boats! Five hundred years later, we are finally learning how to power our homes with solar. Christopher Columbus must be smiling.

It was also a big day in the solar village because water was delivered to each house to fill its supply tank. Remember, we are on the National Mall, and there are no utilities of any kind out here. Each house has a closed system for hot and cold water needs. A big water tank is filled before the contest and used by the decathletes to complete tasks such as washing dishes and taking simulated showers. The used water, called greywater, is drawn off and put in a second holding water tank. After the contest is over, we pump the greywater back into a tank truck and haul it off the Mall.

As if anxious to find a use for some of that new water, many teams began laying out their landscaping and vegetation today. As one example, the Cornell University team began to install their "green screens." Supporting climbing plants, these screens integrate their house's interior and exterior design elements and provide shade on the south side of the house to enhance cooling during the summer. The screens are attached to the house's innovative "Light Canopy," a streamlined framework of steel trusses, independent of the roof, that also supports solar panels and evacuated tubes.