Eighteen student teams design and build sustainable case-study homes on the National Mall in Washington, as part of a Department of Energy-sponsored competition.

Sponsored by the United States Department of Energy as part of an effort to more completely integrate sustainable energy into mainstream society, the second Solar Decathlon, held October 7 to 15, 2005, pitted 18 student teams against one another in a battle on the Mall. Like its Olympic equivalent, the Decathlon included 10 'events,' ranging from architectural merit to hot water generation. In the lighting competition, teams were required to handle both quantitative (measured) and qualitative (judged) criteria, which together comprised 100 points out of 1,100 available in the competition.

The Latin roots of the word 'competition' mean 'strive together,' and the Solar Decathlon exemplifies that, with the communal goal of exploring residential building options that can help reduce national dependence on fossil fuels. Currently, residential buildings account for 21 percent of the energy consumed in the United States.

This event demonstrated the beauty of efficiency-not just in energy consumption, but also in the layout of living spaces that ranged from 650 to 800 square feet. In their designs, teams incorporated a role for the occupant, fostering a more active relationship between user and dwelling that allowed for continual optimization of light and heat conditions. Although full automation might have been technologically achievable, there was a philosophical notion that an intimate relationship with the building would lead to more ownership for residents. Emphasizing interactivity, the Cal-Poly team called its design 'switch-rich'; it took first place in the quantitative lighting competition, and third place overall. Judges noted the house for its fully integrated design and 'livability.'

Teams that succeeded in the lighting category featured natural and electric lighting solutions that emerged organically from the architecture. Daylighting schemes tended to rely on more established techniques of solar orientation and shielding; however, there were several attempts toward innovation. In order to allow light penetration without excessive glare and solar gain, some teams explored translucent panels as an option. The University of Colorado team, first place overall winner, as well as Virginia Tech, winner in the Architecture and Dwelling contests, explored a low-transmission Polygal/Aerogel sandwich for their clerestories.

With electric lighting, innovation came in the form of fluorescent and LED sources. 'It's one thing to put fluorescent in a box and say, 'Wow, this looks just like an office,'' says Gary Steffy, a Michigan-based lighting designer who served as one of three lighting judges. 'It's another thing to make it so you don't notice.' Cal-Poly satisfied this goal through its use of uplighting, notably with a T5HO Cerra Wall fixture from Peerlite.

The Virginia Tech team also received critical acclaim from the judges, winning the qualitative lighting competition. Its 'clean and integrated' design included Lithonia low-profile strip fluorescents to illuminate the roof profile, and sandwiching LEDs between translucent walls, which created a nighttime glow both inside and outside the house. Many teams, including the two mentioned above, were indebted to the generosity of manufacturers, who donated products and materials.

Although by its nature the Decathlon is experimental, the hope is that the techniques developed will have a broader reach. 'I think there's mass interest,' says Bill Sykes, vice president for programming at the Do It Yourself network, which served as one of the primary event sponsors. 'People want to believe that solar, in the right parts of the country, can be practical and cost effective.' zachary r. heineman

Zachary R. Heineman is an employee of Public Architecture, a San Francisco-based nonprofit dedicated to improving the built environment.

project | 2005 Solar Decathlon
competition website | solardecathlon.org
photographer | Stefano Paltera / Solar Decathlon (except where noted)

california polytechnic university solardecathlon.calpoly.edu
canadian solar: concordia university and universite de montreal canadiansolar.org
cornell university cusd.cornell.edu
crowder college crowder.edu/solar/2005
florida international university solar.fiu.edu
new york institute of technology iris.nyit.edu/solardecathlon
pittsburgh synergy: carnegie mellon, university of pittsburgh, and the art institute of pittsburgh pittsburghsynergy.org
rhode island school of design solar.risd.edu
universidad politecnica de Madrid solardecathlon.upm.es
university of colorado solar.colorado.edu
university of Maryland solarhouse.umd.edu
umass dartmouth umassd.edu/solar
university of michigan misohouse.org
university of missouri-rolla and rolla technical institute solarhouse.umr.edu
universidad de puerto rico
the university of texas at austin utsolard.org
virginia polytechnic institute and state university vtsolar.arch.vt.edu
washington state university arch.wsu.edu/solardec

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