The U.S. Department of Energy has posed a voluntary challenge to the homebuilding industry: Build 220,000 high-performance homes by 2012.

The initiative is called the "Builders Challenge," and homes that qualify must meet a 70 or better on the EnergySmart Home Scale (E-Scale).

For more information, visit http://www.eere.energy.gov/buildings/building_america/rh_0208_builders_challenge.html.