By Nalina Moses
This spring you might have spotted work crews on a downtown Los Angeles parking lot heat sealing and tufting industrial vinyl, sewing and filling bags with blown cellulose insulation, and assembling precariously canted wood stud walls. But they weren’t construction workers. They were architecture students and members of the Southern California Institute of Architecture (SCI-Arc) and California Institute of Technology (Caltech) Solar Decathlon team. This unique competition, the U.S. Department of Energy (DOE) Solar Decathlon, is a biennial event that challenges teams of college students to design, construct, and operate a zero-energy single-family home. Among other things, it lures them away from the computer lab and model shop and onto the jobsite.The first Solar Decathlon was held in 2002, with subsequent editions in 2005, 2007, and 2009. To date, more than 15,000 students on 92 school teams have participated in the AIA-sponsored competition. The 20 teams selected as finalists for the 2011 Solar Decathlon are busy fabricating, assembling, and managing shipment of their houses. The completed buildings will be installed as a solar-powered village on the National Mall’s West Potomac Park in Washington, DC, from Sept. 23 to Oct. 2, where they’ll be open to the public. A jury will measure their mechanical performance and judge them in 10 categories related to their energy efficiency, cost, aesthetics, and marketability. As a new category this year, the Affordability Contest encourages teams to design and build affordable houses that combine energy-efficient construction and appliances with renewable energy systems. The goal is to produce houses that focus on passive sustainable design strategies, minimizing dependence on more expensive active energy generation systems while maximizing price-point market readiness. The DOE will announce the winners of individual contests and one overall winner, which will be covered in an upcoming edition of AIArchitect.

What does green “look” like?

Every year, the decathlon offers students from around the world a hands-on opportunity to integrate energy-efficiency strategies with visionary design. This year, however, a dramatic evolution in the design of the houses speaks to an increasingly sophisticated attitude towards green design.

The first entries, in the 2002 and 2005 competitions, were rather simple, trailer-like enclosures padded with banks of solar panels and shading devices. Designs in the later competitions were still basic volumetrically, they were rendered with more specialized details and finishes. “In the first event, in 2002, few knew how to integrate solar systems into the design of a house,” says Richard King, director of the decathlon. “It didn’t take the architects long to discover that they could use PV [photovoltaic] panels for walls, doors, overhangs, and skylights. As you will see from the new designs this year, teams are mastering the art of integrating solar into their houses.”

This year’s Solar Decathlon entries move towards richer and suppler architectural styles. Typical energy-efficient design elements such as ventilation louvers, PV panels, and sun shades appear not as cumbersome accessories, but as integrated architectural elements. In fact, energy-efficient components have been so skillfully presented that most of the houses don’t have to “look” especially green. The SCI-Arc and California Institute of Technology house, a chamfered, tilted volume clad with soft white vinyl, is strikingly contemporary and SoCal in appearance. The Florida International University entry has overhangs and cantilevers reminiscent of a Paul Rudolph Sarasota Modern house. For The City College of New York, whose team designed their house for installation on an existing rooftop, there were multiple strategies at work: exploiting existing infrastructure, leveraging underutilized space, and maximizing solar exposure. Team leader Christian Volkmann explains: “The roof was clearly the most underutilized area we found and–fortunately for our concept–receives the highest solar radiation. This combination triggered our conceptual approach.”

Many of the houses were envisioned with a specific site context, which adds another layer of complexity to the designs. Some teams are designing houses for specific regions and incorporating vernacular design elements. The house by the team from New Zealand’s Victoria University of Wellington has flexible indoor-outdoor spaces inspired by traditional local beach houses. Team Massachusetts (Massachusetts College of Art and Design and the University of Massachusetts at Lowell) designed a building with the taut, self-contained volume of a traditional New England home with a porch that can be enclosed as a sunroom in winter. Parsons The New School for Design and the Stevens Institute of Technology is constructing two houses at once, which will be installed after the decathlon in the Washington, D.C., neighborhood of Deanwood, a site selected in partnership with public housing agencies. The team from the University of Illinois at Urbana-Champaign is designing a structure that can be quickly deployed and assembled for disaster relief. With its long, low facades, it’s strongly influenced by local traditional and Modernist architecture. “The linear aspects of the home draw from the prairie style native to the Midwest, along with the horizontality common in the work of Mies van der Rohe and Frank Lloyd Wright,” says student team leader Beth Newman.

Selling green with high design

In addition to the aesthetic and technical categories, there are the more business-minded areas, including market appeal, communications, and affordability. One goal of the competition is to promote the development of marketable net-zero houses, and the richness in styles and solutions among this year’s participants can go a long way towards promoting this kind of housing to everyday homeowners. If zero-energy architectural solutions are to gain a lasting foothold in the residential market, then homeowners will need a variety of designs to select from. “Teams need to give thought to what makes a house appealing to the public consumer,” King says. “The objective of the Solar Decathlon is to not only educate the students, but also to educate the public so that sales increase and change occurs.”

In 2009, there were more than 300,000 visits in 10 days to individual Solar Decathlon houses displayed on the Mall. This year, surging interest in sustainable technology and residential design should generate even more visitors. “The most inspiring aspect of the Solar Decathlon is walking through the village for the first time and witnessing the amazing diversity and creativity,” King says. While all the houses in the solar village will feature impressive energy efficiency and performance, they’ll also be selling livability, style, and hopefully practicality and frugality as well, helping to bring the fusion of energy-efficient high design one step closer to the mainstream