MIDDLEBURY — Members of the Middlebury College solar decathlon team are kicking their project into high gear as they edge within the five-month mark of the 2011 U.S. Department of Energy Solar Decathlon, which will be held in Washington, D.C., from Sept. 23 to Oct. 2.
More than 75 Middlebury students majoring in 18 different disciplines comprise the first ever liberal arts school team to compete in the solar decathlon alone — operating solo rather than alongside an affiliated university. With a close eye on affordability, a state-of-the-art design and a plan for educational outreach, the Middlebury solar decathlon team is looking to broaden conventional perceptions of sustainable living on both the national and local levels.
Last year, the Middlebury squad emerged from an applicant pool of 45 teams — through two separate heats — to wind up as one of 20 finalists set to compete against teams hailing from as far away as China, New Zealand and Belgium. The Department of Energy’s solar decathlon challenges Middlebury and its competitors to build affordable, attractive, solar-powered houses that maximize efficiency and energy production.
Having just raised the walls of their solar house on April 7, the crew is calling the structure “Self-Reliance.” A project that has been in the works since 2009 is finally coming to fruition after almost two years of grueling preparation. As time quickly ticks down to the competition, the team is working to materialize the stated goal of “reinventing the New England farmhouse.”
FIT FOR VERMONT
The house’s design is meant to produce more energy than it uses in Vermont. The two key components that team Middlebury has taken into consideration are affordability and sustainability.
At the crux of the design is a compact, 1,000-square-foot structure. It’s smaller than a typical New England home, but it uses space effectively by tucking heating equipment away and creating a clear division of communal and private space.
“At its most basic level the fact that we’re designing a 1,000-square-foot home for a family is a little bit of a radical idea … The demands are so much lower for everything because it’s such a smaller space and because we have such a tight envelope,” said architecture co-lead and construction documentation lead Abe Bendheim, who recently graduated from Middlebury.
The house incorporates an integrated greenhouse wall, triple-paned southern-facing glass windows to increase lighting and hold heat, solar hot water heaters, and solar photovoltaic conductors to produce electricity.
“Our house will be net zero, so we’ll have zero energy demand annually,” said Bendheim.
The house will be tied into the electricity grid, and although it will likely use more energy than it provides during winter, zero demand annually means that the house will generate more energy for the grid than it takes out over the course of an entire year.
The students are also using a wide range of natural materials, many of which were sourced locally.
“We’re using college-grown, sustainably forested wood and local Vermont slate,” said student project manager Melissa Segil.
The house’s floors will be made of maple, the frame is spruce and the outside deck is white oak — all harvested in college-owned forests. To reduce oil inputs and greenhouse gas emissions, the designers went above and beyond the call of the decathlon, using cork to insulate windows and cellulose for walls and ceilings.
“Our roof is 21 inches thick and our walls are 11 inches thick filled with densely packed cellulose and braced in everyway you can imagine so that they maintain their form,” said Bendheim.
Although conventional spray foams are more effective at holding heat, they are often found to release greenhouse gases throughout their lifecycle. The cellulose insulation adds a bit of bulk, but it won’t add toxins or greenhouse gases to the atmosphere.
“I think (the solar decathlon organizers) probably still have some kinks to work out because they don’t take that lifecycle analysis into account. But, for the integrity of our own project we are,” said Segil.
COST OT BUILDING
Initially the team hoped to keep the cost of their house — if built for a customer — below $250,000. But at this point team Middlebury’s new projected cost comes to about $260,000.
“(That) is what it would cost (in today’s market) to replicate our design, if someone wanted to build the Self-Reliance home according to our plans and using our materials,” explained Segil.
“One thing we (would) really like to emphasize is that, no, $260,000 for a 1,000-square-foot house (or $260 per square foot) is not ‘cheap,’ but over the lifetime of this house, the occupants will have zero energy bills and can feel good about the quality and healthiness of the materials in their home,” she said.
However, the total cost of the entire project for the house built for this contest is forecast to be around $600,000.
A key factor bumping up cost is that this house is designed to be taken apart, shipped to D.C., and then reassembled. In the future, this type of design might be cheaper if the production of modules were streamlined in an efficient supply chain.
Much of the equipment and building materials for the solar contest home were given to the Middlebury team through a series of donations. But, a project of this scope requires significant funding beyond a $100,000 grant from the Department of Energy.
“We’ve raised $351,000 so far toward our $500,000 goal,” said fund-raising lead Kris Williams.
While the project will burn up more than its fair share of fossil fuels getting to and from the competition, the student designers hope its impact on the building industry might leave a lasting low-fuel impression.
Check out the Middlebury Solar Decathlon Team at http://solardecathlon.middlebury.edu.
Reporter Andrew Stein is at [email protected].