The house also features a robust and innovative 10.9-kilowatt solar array with cylindrical PV cells, to create a passive self-tracking system that collects direct light as the sun moves across the sky.

The house also features a robust and innovative 10.9-kilowatt solar array with cylindrical PV cells, to create a passive self-tracking system that collects direct light as the sun moves across the sky.

Credit: Ian Allen

Tennessee’s Living Light house finished first in the decathlon’s energy-balance and water-heating contests, and logged top-five finishes in architecture, engineering, and appliances. But the team finished last in affordability.

Edgar Stach, associate professor at Tennessee’s College of Architecture and Design, believes that the team’s unique double-façade system contributed to the house’s high estimated cost. The system comprises two panes of glass with a programmable blind system in between for lighting and shading, and is connected to an energy-recovery ventilator that supplies the house with passively warmed or cooled air. “By connecting the double-façade system with the heating and cooling system you can actually use the façade as an energy-plus façade,” Stach says. “In other words, it generates energy throughout the year.”

Stach believes the cost of the façade was overestimated. “Normally, façades like this are built by high-priced façade companies, mostly in Europe, and they’re expensive, I agree,” he says. “Our intent was, with our industry partners, to build the same functionality with standard profiles.” For example, Stach says, rather than using foldable glass wall like other teams, Tennessee chose inexpensive solid glass and simple aluminum frames.

The Living Light house also features a robust and innovative 10.9-kilowatt solar array with cylindrical PV cells, to create a passive self-tracking system that collects direct light as the sun moves across the sky. Because the cylindrical PV cells collect more light in the morning and evening than flat-plate collectors, the team’s engineers say that they can generate more power.

Stach says that the Living Light house will tour the state before returning to campus as a living laboratory. The double-façade? He believes is can be applied today—and not just to houses. “The façade could go into mid-rise to high-rise building,” he says.

Estimated cost: $470,464.58