Europe has had an edge over America when it comes to sustainable design, historically, so it’s little surprise that on Friday students from a German school bested 19 other college and university teams in the 2007 Solar Decathlon, a biennial intercollegiate competition sponsored by the U.S. Department of Energy (DOE) to promote innovative sun-powered, energy-efficient dwellings. The University of Maryland and Santa Clara University placed second and third, respectively.
Held on the mall in Washington, D.C., the event drew more than 120,000 visitors during its two-week run. In this third decathlon, organizer and founder Richard King of the DOE says that there was “more eloquent design, better use of spaces and better integration of solar systems on the house—some of them invisible, some of them are these beautiful wing-like structures.”
The rectangular, oak-paneled house built by architecture students from Technische Universität Darmstadt ranked first in four out of the 10 categories that judges use to evaluate competitors: architecture, engineering, energy use, and lighting. Its interior is based on simple symmetry. A Plexiglas-enclosed unit, which houses the kitchen, the shower and the bathroom, forms the core. On each end of the house is a square cavity that contains integrated furniture units—one cavity is fitted with a bed, the other a seating area.
“It has a very clear parti,” says Susan Maxman, FAIA, SMP Architects in Philadelphia, one of the judges for the architecture category. “It’s a very integrated, consistent house that doesn’t try to do too much.”
This simplicity belies engineering complexities. The house’s exterior consists of four layers, each designed to retain energy. The outermost shell is made of timber shutters that incorporate photovoltaic panels. These shutters can pivot to form louvers and follow the movement of the sun in order to maximum energy generation. Eva Zellmann, a student on the German team, explains that these technical elements were intentionally limited to the house’s exterior: “We don’t want to show all the technology in the rooms because it’d be like living in the machine.”
If the winning house seems more spacious than its 800 square feet, a limit mandated by the competition’s rules, that’s because its north-side glass wall opens onto a patio, also clad in oak panels so that it maintains continuity with the structure’s facades. “The outside flows into the inside,” Zellmann says. “The deck is extending outside.”
The Solar Decathlon was first opened to international teams in 2005. That year, some members of the Technische Universität team competed on a team from Carnegie Mellon University. The Germans were going to join forces with Carnegie Mellon again, but ultimately decided that the transatlantic challenges of designing and building a solar-powered house together would prove too complicated. In this year’s competition, Carnegie Mellon placed No. 14.
The next Solar Decathlon is scheduled for 2009, in the United States, but the Germans and other international teams might not need to cross the Atlantic Ocean to compete. Just last week, the DOE signed an agreement to host a decathlon in Spain in 2010.