According to the Environmental Protection Agency (EPA), a number of states are seeing a significant number of new homes being built according to green building standards.

The agency reports that in 15 states, more than 12 percent of new homes are meeting so-called Energy Star standards. The leading states are Alaska, Arizona, California, Connecticut, Delaware, Hawaii, Iowa, Nevada, New Hampshire, New Jersey, New York, Ohio, Texas, Utah and Vermont.

The Energy Star program is a joint effort of the EPA and the Department of Energy (DOE), which was started in 1992. To qualify for the rating, a home must now be at least 15 percent more energy-efficient than homes built to the 2004 International Residential Code. An Energy Star home includes additional energy-saving features that can make it actually 20 to 30 percent more efficient than a standard home.

Collectively, the 15 states have contributed to a dramatic shift in green building practices across the country. According to the EPA, nearly 200,000 new homes nationwide earned the Energy Star in 2006. The total number of these homes across the country now is approaching 750,000. They have saved more than 1 billion kWh of electricity, and locked in more than $180 million in annual savings on energy costs for their owners. EC