The ultra-energy-efficient Empowerhouse, an audience favorite in the U.S. Department of Energy’s 2011 Solar Decathlon, recently took on a new identity just a few miles from where it was toured by 50,000 visitors during the two-week-long competition on the National Mall.
After the competition ended, project planners moved the structure to the working-class Deanwood neighborhood of Northeast Washington, D.C., and expanded it into a two-family, two-story duplex for local low-income residents. It officially opened earlier this month.
The super-insulated, Passive House-certified home is seen as a model for sustainable low-income housing, thanks to a unique partnership between the Solar Decathlon team, Habitat for Humanity of Washington (DC Habitat), and the D.C. Department of Housing and Community Development. The $229,000 project, which took first place in the Decathlon’s Affordability category, marks the first time that a team partnered from the outset with civic and government agencies to create a house for a local community.
Each unit of the two-family house is designed as a separate net-zero system, but each achieves peak efficiency when joined, consuming up to 90 percent less energy for heating and cooling than a typical home. Thanks to airtight construction and high-performance insulation, the house required one of the smallest photovoltaic arrays of any in the 2011 Solar Decathlon, and its heating and cooling will require the same amount of power as it takes to operate a hair dryer, which is critical for the owners, says Michael P. Kelly, director for the D.C. Department of Housing and Community Development.
“It’s one thing to be able to bring a family into a house and an affordable rate, but it’s another thing to be able to keep them there due to affordable operating costs,” he says. The home is expected to save each family about $2,000 on utility bills each year.
Building on the theme of self-empowerment, a roof garden and vegetable window boxes will provide families with the opportunity to grow their own food. The house also has a comprehensive water strategy that includes a rainwater harvesting system to capture and store rainwater for use in the garden, with the ultimate goal of minimizing the water that is drained into the public sewer system.
The community played a direct role in building the house, in keeping with the Habitat for Humanity mission, and the house features an innovative construction system that facilitates volunteer participation, as well as many off-the-shelf components that are available in home improvement stores. 
The Empowerhouse was originally designed and built by students from The New School and Stevens Institute of Technology who participated in the 2011 Solar Decathlon. The biannual competition challenges collegiate teams from around the world to design, build, and operate solar-powered houses.
"This project fulfills a longstanding vision of our team to create a house that would endure in a meaningful way after the Solar Decathlon was over,” says Joel Towers, executive dean of Parsons The New School for Design.
The project’s potential for national and international replication has already gained momentum, says Towers, noting that Parsons is in the planning stages of building a similar home with Habitat for Humanity in Philadelphia. In addition, DC Habitat recently announced groundbreaking on six new energy-efficient townhomes based on the Empowerhouse’s Passive House design standards.