Energy Star Buildings Cut Emissions and Energy Costs

To save on energy costs, many Americans have installed weatherstripping and new insulation in their homes. For the owner of a large office building or manufacturing plant, the task can be much more daunting. According to the Department of Energy and Environmental Protection Agency, commercial buildings and manufacturing plants account for nearly half of all U.S. energy consumption, as well as nearly half of all U.S. greenhouse gas emissions. Altogether, energy usage at these buildings costs over $200 billion per year. The Environmental Protection Agency's Energy Star certification system aims to inspire organizations to make building improvements to improve energy efficiency. California is leading the way in these certified buildings. Five Golden State cities are among the 25 U.S. metro areas with the most Energy Star buildings, including three California cities in the top 10.

[See a slideshow of the 10 cities with the most Energy Star certified buildings.]

Naturally, the most populous urban areas in the nation­—New York, Los Angeles, and Chicago—are among the 10 cities with the most certified buildings. But Sacramento, the 25th-most-populous metropolitan area (according to 2009 Census figures), came in at No. 8 for Energy Star buildings. In addition, Denver, the 21st-biggest city, comes in at No. 11 with 146 Energy Star buildings. Conversely, some of the largest cities in the nation are nowhere near the top of the Energy Star list. For example, Philadelphia, the fifth-largest metropolitan area in the nation, is 14th in terms of Energy Star buildings.

Organizations that want to show that they are working to be energy efficient can apply for Energy Star certification from the Environmental Protection Agency. A wide variety of facilities can apply for the distinction, including supermarkets, hospitals, food production plants, and manufacturing facilities. To apply, an organization submits detailed information on key factors in its energy usage. For example, for an office building, the EPA would want statistics on the amount of office and parking space, the number of computers in use within the building, and how much of the building is air-conditioned or heated. Buildings that earn the Energy Star certification must perform better than at least 75 percent of similar buildings nationwide. According to the EPA, certified buildilngs cost 50 cents less per square foot to operate than average buildings.

These are the 10 metro areas that had the most Energy Star-certified buildings in 2010.

Metro Area Number of Energy Star Buildings Total Floorspace (million sq. ft.) Cost Savings (millions) Emissions Prevented (equal to ___ homes' electricity use)

1. Los Angeles 510 106.1 117.9 39,800

2. Washington, D.C. 301 75.2 74.2 42,600

3. San Francisco 248 61.4 75.1 25,600

4. Chicago 232 92.9 62.7 54,500

5. New York City 211 76.4 86.6 36,500

6. Atlanta 201 51.6 38.7 38,700

7. Houston 175 70.8 62.9 47,300

8. Sacramento 168 16.9 19.1 6,900

9. Detroit 151 27.4 18.7 17,400

10. Dallas-Fort Worth 148 40.6 35.2 26,300

Los Angeles is notable for having been the No. 1 city for three years in a row. It also saved the most money and had the most floor space in its Energy Star buildings out of all of the top 25 metro areas in the United States. Chicago, however, prevented the most emissions, blocking the equivalent of 54,500 homes' worth of electricity use.

One factor that likely pushed some cities toward the top of the list is the number of commitments from some corporations to achieve certification in their buildings. The EPA counts JCPenney, Staples, Target, and USAA as companies that have set certification goals.

The environmental and budgetary incentives to get certified have helped to drive up the number of participants considerably. Last year saw sharp growth in the number of buildings achieving certification. More than 6,200 commercial buildings were certified last year, up 60 percent from 2009.