AMES, Iowa -- When Iowa State University participated in the U.S. Department of Energy's 2009 Solar Decathlon competition, the plan was to eventually monitor the long-term performance of the solar-powered Interlock House, which was designed and constructed by students.
The Interlock House has been reassembled at the Iowa Department of Natural Resources' Honey Creek Resort State Park for use as the nature interpretive center and staff offices. Iowa DNR owns the house and led the reassembly.
Researchers from Iowa State's Center for Building Energy Research (CBER) are gearing up to track the building's performance in Iowa's climate, says Architecture Assistant Professor Ulrike Passe, who directs the center. CBER is a member of the Institute for Physical Research and Technology, a network of scientific research centers at the university.
"This is a unique opportunity for real-time, long-term building performance evaluation of a net-zero energy building in Iowa," Passe said.
The Interlock House successfully produced more energy than it used during the week of the competition in Washington, D.C. Although the house was designed for the extremes of the Iowa climate, it has yet to operate through the full range of a hot and humid Iowa summer and a bitter, cold winter.
The Interlock House has been reassembled on a new basement. On the south side, a walkout basement has been added below the deck.
With technical assistance from DOE's National Renewable Research Energy Laboratory (NREL), Golden, Colo., the house has been outfitted with about $12,000 worth of sensors, jointly funded by IPRT and Iowa DNR. The sensors will monitor indoor temperature and humidity, along with electricity consumption. And electrical and thermal energy production at the house will be recorded.
For the first year of the project, CBER researchers will evaluate whether the goal of the Interlock House to obtain a net energy balance or surplus can be achieved on an annual basis. Comfort and energy performance data from the house's sensors will be compared to weather data. And performance will be evaluated against current industry standards. Appropriate adjustments to the systems and controls will be proposed for the second year, if needed.
Last spring, Dana Sorenson, Clark Colby and Mike Garcia -- three recent ISU architecture graduates -- worked for CBER on the design of the data acquisition system and installation of the thermal, electrical sensors and dataloggers. All three students were decathletes on the National Mall in Washington, D.C.
Noelie Daviau joined the research team in March for five months
as a CBER intern. Daviau is a student engineer from The ENTPE
(National Graduate School of Sustainable Development, Civil
Engineering, Building, Transports and Planning) near Lyon,
France. And, Nick Hulstrom -- a third-year architecture student
who had helped construct the house as a freshman -- rejoins the
project this summer. He will continue the research into
Daviau has been conducting a review of research publications about the application of renewable energies to energy-efficient building design. With support and knowledge from the three graduating students, she is writing the manual for the Iowa DNR staff who will operate the house. Daviau and Hulstrom will interpret data as measurements become available.
Iowa State, NREL and Iowa DNR will share the data. DNR will use the information in their public outreach on energy efficiency.
Passe and her team will use the data to verify assumptions and evaluate the design strategies.
"And it will be important to give feedback to the commercial companies whose products we used," she said. "They want to know how well their products worked."
The Iowa State researchers will make their findings public online.