Solar Decathlon Shows Net Zero Energy Viability

November 23, 2009
/ Print / Reprints /
/ Text Size+
Visitors stand in line waiting to view Team Germany’s solar-powered house, which won the 2009 Solar Decathlon. (Feature photos courtesy of Stefano Paltera/U.S. DOE Solar Decathlon.)

WASHINGTON - Rain normally spoils a solar power contest. But three days of showers - and the use of thin-film photovoltaic (PV) technology - actually helped Team Germany win the 2009 U.S. Department of Energy (DOE) Solar Decathlon.

Team Germany was followed by the University of Illinois at Champaign-Urbana in second place, and Team California in third. The winners were announced by DOE Deputy Secretary Daniel Poneman at the competition site on the National Mall in Washington, D.C.


Team Germany’s “Cube House” actually produced a surplus of power despite the three rainy days during the two-week contest. Every exposed face of the building was covered with power-generating panels.

On the roof there was a 11.1-kW PV system of 40 monocrystalline silicon panels. On the sides there were 250 thin-film panels that looked like glossy clapboards. The thin films used copper-indium-gallium-diselenide (CIGS) layers.

The combination system was expected to produce 200 percent of the energy needed by the house. The thin-film panels, while less efficient than conventional silicon, were projected to perform better in cloudy weather than silicon.

Team Germany got proof of this expected performance on the competition’s fifth day when skies turned gray and a cold rain dampened the contest’s solar village. By late afternoon, as D.C. commuters started going home and electricity demand throughout the city began climbing, the Team Germany house was producing 12.68 kW and consuming 12.33 kW, for a net export of 0.35 kW. “Team Germany built a gingerbread house packed with solar panels,” said Richard King, DOE Solar Decathlon director. “In the rain, the thin-film panels were making electricity. It made the difference.”

Penn State students Luke Witmer (left) and James Gawthrop (right) explain their house’s mechanical room to Penn State Associate Dean Alan Scaroni during the 2009 Solar Decathlon.


In addition to educating the next generation of renewable energy engineers, architects, and green builders, the Solar Decathlon is intended to help propel solar energy and energy-efficient products into the marketplace and to demonstrate the potential of zero energy homes.

The 2009 Solar Decathlon challenged 20 student teams from across the United States, as well as from Canada, Germany, and Spain, to compete in 10 contests, ranging from subjective elements such as architecture, market viability, lighting design, and engineering, to technical measurements of how well the homes provided energy for space heating and cooling, hot water, appliances, and net metering.

New to this year’s competition, the Net Metering Contest challenged teams to generate surplus energy, above and beyond the power needed to run a house, which they fed into a power grid.

Inclement weather didn’t deter the crowd that came to see the 2009 Solar Decathlon on the National Mall in Washington, D.C.

Of the 10 contests, Team Germany’s surplus power production earned the Net Metering award, which carried the greatest weight at 150 points. Team Germany also won the Comfort Zone contest for 100 points by best maintaining a comfortable temperature and humidity in its home. The requirements were to maintain an average indoor temperature of 72° to 76°F and maintain humidity of 40 to 55 percent.

The second-place University of Illinois team took top honors in the Hot Water contest, which required producing enough hot water for regular showers; the Appliances contest, which involved running a refrigerator and freezer, dishwasher, washer, and dryer; and the Home Entertainment contest, which involved not only running a television, computer, lights, and a cooking appliance, but also hosting two dinner parties and a movie night.

And although its team didn’t place in the top three, the University of Minnesota team won the Engineering award, honoring the solar home that best exemplified excellence in energy systems design, energy-efficiency savings, creative innovations in design, and reliability of energy systems.

Publication date: 11/23/2009

Did you enjoy this article? Click here to subscribe to The NEWS Magazine

You must login or register in order to post a comment.



Image Galleries

2014 MCAA Annual Convention

Scenes from the 2014 MCAA Annual Convention in Scottsdale, Ariz.


NEWSmakers: Julian Scadden

Training is an ongoing process. Julian will discuss how you can generate maximum return on time and energy invested training by following a three part process. Listen to this podcast to get expert tips on training, tracking and follow up. 

More Podcasts


NEWS 04-21-14 cover

2014 April 21

Check out the weekly edition of The NEWS today!

Table Of Contents Subscribe


Which statement on service calls best applies to your business?
View Results Poll Archive


2014 National Plumbing & HVAC Estimator

Every plumbing and HVAC estimator can use the cost estimates in this practical manual!

More Products

Clear Seas Research


Clear Seas ResearchWith access to over one million professionals and more than 60 industry-specific publications, Clear Seas Research offers relevant insights from those who know your industry best. Let us customize a market research solution that exceeds your marketing goals.


Magazine image
Register today for complete access to Get full access to the latest features, Extra Edition, and more.


facebook icontwitter iconyoutube iconLinkedIn i con