Solar Gets Hot Down On the Mall

Posted October 16, 2009 at 4:25pm

The winner of the 2009 Solar Decathlon, sponsored by the Department of Energy, is a German-built home that actually produces twice the energy that it uses through its clever use of solar panels.

The house, created by Team Germany, a group of 24 architecture and engineering students, was one of 20 solar homes constructed last week on the National Mall by university students from across the globe.

Each team in the competition was awarded $100,000 in seed money from the Department of Energy and given two years to create a 500- to 800-square-foot home, transport it to the Mall and set it up within seven days.

The Department of Energy’s Richard King, who ran the competition, said, “The decathlon gets its name from 10 ways to measure a house, not only subjectively, where we have professional architects evaluate their esthetics and professional engineers who are looking at engineering excellence, [but] we also measure these houses for performance.—

During the contest, each house was judged by its architecturally attractive design and market viability, according to a target market, as well as its suitability for everyday living. “Each home must be able to wash dishes, cook, wash clothes, run televisions for six hours a day, have their home theaters and run through everything that a normal family would do in these houses all powered solely from the sun,— King said.

Homes were also judged on the basis of their engineering functionality, reliability and efficiency. Temperature and humidity sensors were set up within individual living areas and thermal measuring instruments placed in all refrigerators and freezers.

“At the end of the contest, in a well-rounded way, you find out who has the best house — where it not only looks good, but performs very well,— King said.

A spokesperson from Team California, Annabel Peterson, said what set her team’s home apart from others was that “it is not just a box; we wanted to take apart the box, and that’s what we did in this instance. We broke apart the functionality with regards to where each of the functions occur. The deck looks like the fourth room of the house.—

Team California, which received the highest ranking for architecture and communication, is made up of the combined efforts of students from Santa Clara University and California College of the Arts. Their target market was empty-nesters who want to simplify their lives.

Adjacent to the deck was a self-sustaining landscape with native plants that required little or no care. According to Peterson, the edible garden was watered through a constructed wetland that used the greywater from the home’s washing machine and served as a gravity-fed biofilter made of several layers of sand, gravel and soil. After the greywater flowed through the bottom of the wetland, it was considered clean. While the home could also withstand 150 mph winds, it was designed for arid regions of the United States.

Team Puerto Rico, on the other hand, had a target market of humid climates, such as those in Florida, Louisiana or the Caribbean. The 804-square-foot home incorporated several passive solar shading screens that reduced glare and radiation by 86 percent. Reclaimed teak park benches were used on the floor and veneer of the home.

Project manager Sonia Miranda Palacios said she believes all consumers should be “energy producers.— Palacios pointed out the only real difference between their constructed home and everyday homes is the source of energy. Every home could be transformed into a zero-energy house for around $4,000 to $7,800, she said. The transformation would require photovoltaic panels and an inverter to change the current. Consumers would use the same wiring system in their house and energy-efficient appliances available at many home-improvement stores.

The PV panels absorb the energy from the sun, Palacios said, and the inverter converts it into alternating current and direct current, and then the current is fed into the existing electrical grid within the house’s infrastructure. The exchange of energy generated and consumed is measured and recorded by a home’s electric meter. Additional energy can then be sold to your local energy authority. Maybe that’s why Team Puerto Rico named its house “Cash.—

The winner, Team Germany, used a facade of integrated solar panels with acrylic glass on a two-story loft home.

According to Team Germany student Ramzia Rahmari, the house produces twice the amount of energy that it consumes. This attribute shot the house into first place overall, beating the majority of participants by a landslide in the net metering contest.

“I think everyone who took part in this competition is a winner for her or himself … and I think that is the most important thing,— Rahmari said.