University of Maryland placed first in the
overall U.S. Department of Energy
Solar Decathlon 2011
Photo by: Dept of Energy Solar Decathlon

Notions of urbanism and density are creeping into the Solar Decathlon, a biennial solar-home competition sponsored by the U.S. Department of Energy (DOE). While many of the prototypes on display in Washington, D.C., in late September still had a suburban or rural live-off-the-grid purpose, some university groups have begun to design homes attuned to the needs of their schools’ urban settings. And most entries employed a holistic approach to sustainable living, including water management and local sourcing, even though such features are not rewarded under the competition’s criteria.

Uwe Brandes, an architect and urban planner who is ULI’s senior vice president of initiatives, toured the temporary solar village, evaluating how various designs could be adapted to dense, urban settings. “Overall, it’s interesting to see that a number of the student-designed houses are consciously transcending DOE’s constraints for the competition,” he said. “To me, this indicates that these students are interested in pursuing a deeper strategy of sustainability over the relatively simplistic idea of just putting solar panels on a prefabricated box. Water recycling, locally sourced materials, designs that engage exterior spaces—these are all strategies for connecting to local economies and environments.”

Certainly there remains a strong go-it-alone streak in many of the designs. For example, a team from the University of Calgary designed a solar-powered home specifically for the needs of Native Peoples living on the southern Alberta prairie, while students from Victoria University of Wellington, New Zealand, designed a vacation home for rural settings near their coast. Students from Purdue University built a solar home, complete with one-car garage, that could be slipped into a typical Indiana suburb incognito.

But students from the City College of New York built a structure designed to rest atop a prewar mid-rise building in New York City. Not only could it provide solar power for its intended occupants and possibly energy for the host building, but it also incorporates roof-garden and stormwater-retention features.

RazziSolar_3_351  RazziSolar_4_351 
Exteriors of entries from: Illinois (left) and SCI-Arc/Caltech (right)
Photo by: Dept of Energy Solar Decathlon

“This tells an urban story,” Brandes said. “Certainly in New York there’s a huge trend in recovering rooftop space.” And he noted that the compact design could be adapted to a ground-level urban setting. “You could imagine this stacked three or four high. Add an exterior stair, and then it becomes a walkup typology,” he added.

Two other New York–area schools—Parsons the New School for Design in Manhattan and Stevens Institute of Technology in Hoboken, New Jersey—teamed up to produce a home that will soon be used in an urban setting: the Deanwood neighborhood of Washington, D.C. It will become a Habitat for Humanity home for a single mother and child. With a construction cost of only $229,890, it took top honors in the Decathlon’s affordability contest.

The designers minimized the need for expensive solar panels by emphasizing insulation. Sunshine and body heat may be enough to warm the interior on most winter days, according to the designers.

“This is a great example of a ‘passive house’ strategy,” Brandes said. “It’s very low-tech; there’s no reason why this can’t happen today, and it represents huge savings in energy bills for those who will be fortunate to occupy the house.”

Touring the prototype home built by students at Belgium’s Ghent University, Brandes raved about its potential for urban settings. Their “E-Cube” home, a modular steel structure clad in thin concrete panels, is designed as a do-it-yourself kit that allows the owner to add modules and interior finishes as his or her needs and finances change. The cube allows for a second story to accommodate sleeping, bathing, and storage. The modules could be stacked to provide three levels, possibly with the solar panels suspended above a rooftop deck, Brandes noted. “You can imagine this house being the elemental building block of an entire master-planned neighborhood,” he said.

The University of Maryland extorior 
Photo by: Dept of Energy Solar Decathlon

Over the course of two weeks, students open the homes to the public and compete in ten competitions: architecture; market appeal; engineering; affordability; communications; heat and humidity control; hot-water production; appliance operation; home entertainment (hosting dinner parties and using televisions and other home electronics); and producing enough solar power to achieve a net-zero energy consumption.

It bears noting that the competition does not award points for use of renewable resources, stormwater management, water conservation, or indoor air quality. But the multidisciplinary design teams are taking it upon themselves to make such issues a focus of their designs. For instance, the University of Maryland, whose house took top honors overall and won the architecture category, focused heavily on water management, a key ecological issue in the Chesapeake Bay watershed. Their home captured rainwater and recycled graywater from washing to irrigate its heavily planted outdoor gardens. They also used a patent-pending technology developed by the university for its 2007 Decathlon entry, which uses a lithium chloride desiccant to reduce indoor humidity, easing demand on the air-conditioning system.

“You can see the students are pushing the envelope and seeking to move beyond just producing renewable energy,” Brandes said. “I wouldn’t be surprised if the competition begins to change to incorporate issues such as embodied energy and location efficiency.”

More information about the Solar Decathlon can be found at