WASHINGTON, DC — Los Angeles, Washington, D.C., and San Francisco head the list of cities with the most energy efficient buildings, according to the U.S. Environmental Protection Agency.

The EPA released its second annual list of rankings today of metropolitan areas that are home to buildings bearing the Energy Star label. Buildings that attain Energy Star standards of efficiency earn the program's label.

The program awarded its first label to a building in 1999, and by the end of 2009 almost 9,000 commercial structures in the United States had received the Energy Star plaque.

Annual utility savings resulting from Energy Star building efficiency are estimated at more than $1.6 billion. The equivalent of greenhouse gas emissions from more than 1 million homes have been prevented as a result of the program, according to the EPA.

This year the agency's Top 25 list includes 27 cities -- three cities tied for 24th place: Des Moines, Iowa, Fort Collins, Colo., and Philadelphia, Penn.

The list of the top 10 cities follows. The full list can be found at www.EnergyStar.gov (pdf).

Los Angeles topped the list for the most Energy Star buildings, the greatest amount of efficiency rated square footage under the program and the greatest amount of savings.

Houston, in sixth place, avoided the great amount of greenhouse gas emissions (see full list)  by preventing emissions equivalent to those from 53,400 homes.

Last year, 3,900 commercial buildings were awarded Energy Star labels, making the total of Energy Star buildings in the U.S. 40 percent higher than in 2008. Structures whose energy efficiency performance place them in the top 25 percent, compared to comparable commercial buildings nationwide, are eligible for the label.

The EPA estimates that energy use by commercial buildings accounts for 17 percent of U.S. greenhouse gas emissions at a cost of more than $100 billion each year.

Image CC licensed by Flickr user Kevitivity.