WASHINGTON IS KNOWN MORE FOR FILIBUSTERS than for innovative design. For one rain-soaked week in October, however, innovation was the word when 18 university teams converged on the city for the Solar Decathlon, an event in which students compete to see who can design, build, and operate the most-attractive and energy-efficient solar-powered house.
By week's end, the University of Colorado won the overall event, but every team was successful in demonstrating that solar energy could be the bright spot of an energy future that is starting to look dim.
Solar technology—that is, photovoltaic panels—is not a new idea and has not been a particularly cost-effective one either. Though clean and renewable, the technology has been costly, and panels have been rather inefficient compared with other sources of energy. But solar power is gaining momentum due to incentives (in the form of grants and other state programs to encourage homeowners to use the technology), tax breaks, advances in the technology, and the rising cost of fossil fuels. As a result, solar installations increased 27 percent last year.
But the Solar Decathlon was more than just about energy; it was an exercise in how to gracefully knit the technology into the architecture.
The University of Maryland focused on designing a house with broad appeal. “We made a strong effort to create a warm and comfortable home,” says student Tom Serra, construction group leader. “The surfaces and finishes are similar to what you would see in the average American home.” Energy comes from the 51 panels integrated into the curved roof. Radiant-heated concrete floors, natural-fiber insulation, and passive solar heating make the interior comfortable; bamboo and recycled glass help make it attractive.
Virginia Polytechnic Institute and State University focused on a more cutting-edge design. “We were trying to go for integration of the engineering systems within the architecture,” says Brett Moss, a master's candidate who used the house for his thesis. “The way we look at it, the architecture enhances the engineering.” A butterfly roof tilted slightly screens the panels, while its center drains rain into a cistern for gray water use. The house gets its ghostlike radiance from translucent polycarbonate walls that bring in light yet offer privacy. Instead of traditional insulation, the two layers of polycarbonate are injected with an aerogel that delivers an energy-efficient R-value of 22.
California Polytechnic State University pursued a strategy that builds on prefabrication. “Our idea here is one-truck transport,” says Nicholas Holmes, a fifth-year architecture student. “We shipped this house on one trailer and added the additional height, solar panels, awnings, and rooftop deck on site. It reduces our transportation, cost, and pollution.” Built with 6-inch SIPs, the house has R-23 walls and an R-37 roof and floor. “We have reduced a lot of our energy needs just by having a tight envelope,” Holmes says. A breathable housewrap lets moisture out but not in, and sleek wood/resin panels create a low-maintenance shell.
Interest in solar is growing, but the technology still has obstacles to overcome—high upfront costs, for one. “If you want three kilowatts for your house”—the average system a homeowner might install—“it is going to cost you [close to] $30,000,” says Richard King, director of the Solar Decathlon at the Department of Energy. Another barrier is aesthetics, he notes. “A lot of people don't want these contraptions on their roofs.”
But the event proved the panels can be successfully integrated into the roof. “If you design the house from the ground up and the solar is incorporated in it, the aesthetics are better,” King says, adding that rolling the system into a mortgage is a wise idea. “You might be paying $30 more per month for your solar system, but you are saving $70 a month too.”
“The technology is fantastic, and it is events like the decathlon that bring it into the public eye,” says John J. Loyer, a construction, codes, and standards specialist at the NAHB, an event sponsor. He says the technology is still expensive, so “to fully support it, the NAHB would like to see it become much more cost effective and affordable.” But if affordability can be achieved, solar could play a vital role in America's future housing and energy needs.
Learn more about markets featured in this article: Washington, DC.