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Photo of Colorado's 2005 Solar Decathlon team standing and sitting among building materials with the Rocky Mountains in the background.

The Colorado team emphasizes use of natural building materials.

Computer-generated image of Colorado's 2005 Solar Decathlon house.

From soy insulation to PV panels, Colorado's modular house showcases sustainable building materials and advanced energy technologies.

Solar Decathlon 2005

University of Colorado

It's the Natural Place to Be, No Matter Where You Are

The materials used in the University of Colorado's home read like a health food restaurant menu. Soy, corn, sunflower, canola, coconut—these are just some of the natural "ingredients" in many components and furnishings (and even tableware) featured in this unique modular home. What's more, naturally derived fuel will be used to transport the home to and from Washington, D.C.

Using natural materials was one of the team's five major design goals, along with innovation, energy efficiency, modularity, and accessibility. The result is a sustainable, attractive solar home built almost entirely of recycled and natural materials—one that can go almost anywhere to complement almost any lifestyle.

The Colorado team is especially eager to unveil the innovative, biobased structural insulated panels—BIO-SIPs—used for the walls. Julee Herdt, one of the team's faculty advisors, developed the BIO-SIP with the help of researchers at the U.S. Department of Agriculture's Forest Products Laboratory in Wisconsin. It meets all building code requirements and is patented for use in future products. BIO-SIPs merge two commercially available green products: strong but lightweight Sonoboard, made of recycled cellulose materials by Sonoco Company, and BioBase 501, a lightweight foam insulation made of soybean oil by Biobased Systems.

The BIO-SIPs and high-performance window glazings contribute to the home's energy efficiency. So does the integrated radiant solar thermal system used for space and water heating. "We wanted a nonintrusive, ductless heating and cooling system, and this really fits the bill," says Kendra Tupper, student leader of the engineering team.

The team also carefully selected the home's rooftop PV system and building-integrated PV awnings, which provide shade as well as electricity. "Our rooftop PV system is made of 32 SunPower 200-watt panels; they're around 16%-17% efficient," says Jeff Lyng, student project manager. After the Solar Decathlon, the home will be set up again and connected to a utility as part of the university's education and outreach activities.

The 2005 team wants its home to compare favorably with the university's 2002 Solar Decathlon entry, which took top honors. "Our 2002 goal was to create an energy-efficient solar home that would fit right into an American suburb, so it was a little bit conventional," says faculty advisor Michael Brandemuehl. "In 2005, students are using more innovative materials and solar technologies to create a modular home for the future."

Team Contact

Prof. Julee Herdt
ENVD Building
Campus Box 314
Boulder, CO 80309-0314