All eight homes in Weatherford Place are designed to be net-zero energy. Photo: Cadmus Construction

The metal-roofed model, which is already contracted for sale at $749,000, has been selling power to Georgia Power and Southern Co. for nine months. Simone du Boise, principal of Cadmus Construction, says her design/build firm mandates alternative green, sustainable power sources in all its buildings. “We are building the house next door with the energy from the model, which has a finished basement that brings air-conditioned space to 4,000 square feet. And we still have a credit with Georgia Power,” she notes.

The homes use a holistic, integrated approach that include active solar photovoltaics and solar thermal to generate free hot water. It also employs many passive solar design elements and healthy-house features. “We achieved the lowest HERS (Home Efficiency Rating System) score on record, a 47,” says partner Denise Donahue, “and a lot of our building science is not even considered in that rating because there's no data on it.” A base HERS-rated home, built to the 2006 energy code, scores 100. Most new homes don't match that standard.

Donahue and du Boise plan to franchise their “EcoCraft Home” system to builders throughout the country.