Constellation Energy (NYSE: CEG) today announced that it has been named to the 2010 Dow Jones Sustainability Index (DJSI) North America which tracks the financial performance of leading sustainability-driven companies. This marks the fifth time that Constellation Energy has been named to the index. The DJSI provides an objective benchmark on sustainability for investors and financial portfolio managers.

?We are pleased to once again be listed among North America's most sustainable companies and proud of the environmental, operational and civic accomplishments of Constellation Energy and our employees,? said Mayo A. Shattuck III, chairman, president and CEO of Constellation Energy. ?Our commitment to sustainability benefits Constellation Energy's investors and employees and the communities we serve today, and creates new opportunities to shape a sound energy future.?

Constellation Energy is one of 11 U.S. companies named to the 2010 DJSI North America in the utilities sector. DJSI conducts an annual review of corporations both regionally and globally across a wide range of industry sectors. The results are based on a thorough analysis of set criteria, which include a corporation's economic, environmental and social performance. Investors worldwide monitor the lists annually to determine which companies are successfully establishing and achieving sustainability initiatives. The index also focuses on financial transparency and measures stock market performance. The rankings help encourage corporations to invest in sustainability initiatives, as well as to reduce the current and future risks associated with industry wide performance benchmarks.

About Constellation Energy

Constellation Energy (www.constellation.com) is a leading supplier of energy products and services to wholesale and retail electric and natural gas customers. It owns a diversified fleet of generating units located in the United States and Canada, totaling approximately 9,000 megawatts of generating capacity, and is among the leaders pursuing the development of new nuclear plants in the United States. The company delivers electricity and natural gas through the Baltimore Gas and Electric Company (BGE), its regulated utility in Central Maryland. A FORTUNE 500 company headquartered in Baltimore, Constellation Energy had revenues of $15.6 billion in 2009.

Constellation Energy
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Aaron Koos, (410) 470-7433
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Carim Khouzami, (410) 470-6440