Constellation Energy (NYSE: CEG), the nation's leading competitive electricity supplier to business and public sector customers, today announced it is offering increased savings to approximately 1.5 million Illinois residents in both the ComEd and Ameren service territories. More than 223,000 Illinois residents have made the switch to a new electricity provider since the state's residential electric market opened up a year ago.

Through either 12- or 24-month service plans, consumers may be able to experience savings of up to 18 percent off ComEd's current rate and up to 22 percent off current rates in the Ameren service territories. Constellation customers who sign up for a 24-month service plan will lock in their new price for the plan's duration, protecting their price against rate changes during that time. Constellation customers who refer a friend may be eligible to receive a $25 Constellation Visa® Prepaid Card.

"More than 200,000 Illinois residents have already experienced lower rates and price certainty by choosing an alternative electricity supplier, and we hope our latest offer will encourage more Illinois consumers to take advantage of potential savings on their electricity bills," said Kenny Matula, senior vice president of Residential Markets for Constellation Energy.

Aside from a low and locked-in electricity supply rate, new Constellation customers will experience no changes in how their service is provided. There is no interruption in service, no new equipment or installation, and no sign-up fees from Constellation, and ComEd or Ameren will still supply the monthly bills.

"We recognize the value and peace of mind fixed rates and cost savings bring to consumers and their families, especially during challenging economic times," Matula said. "Our goal is to extend that benefit to as many Illinois residents as possible."

The company's direct mail offer to Illinois homeowners and renters is in effect through March 2, 2012. Constellation Energy offers a simple online sign-up process at home.constellation.com. Customers also may call 866.577.4700 to sign up by phone.

The Illinois Commerce Commission (ICC) is the state agency that oversees the competitive retail electric market in Illinois. Additional information about customer choice and competition in the Illinois retail electric market can be found on the Illinois Commerce Commission's website at: http://www.pluginillinois.org/.

ComEd's and Ameren's rates are subject to change and, therefore, we cannot guarantee savings over the full term of our price plans. Constellation's price does not include any taxes, utility distribution charges or other utility fees, charges or credits. In ComEd's service territory, estimated savings are based on ComEd's current BES residential (non-electric space heating) rate. Customers on ComEd's BES residential (electric space heating) rate will not save. In Ameren, estimated savings are based on Ameren's current BGS residential (non-electric space heating) rate for the rate zone in which customer resides. Customers on Ameren's BGS residential (electric space heating) rate will not save. For additional information on our price comparison, visit home.constellation.com.

About Constellation Energy

Constellation Energy (www.constellation.com) is a leading competitive supplier of power, natural gas and energy products and services for homes and businesses across the continental United States. It owns a diversified fleet of generating units, totaling approximately 12,000 megawatts of generating capacity, and is a leading advocate for clean, environmentally sustainable energy sources, such as solar power and nuclear energy. 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 $14.3 billion in 2010. Learn more online: www.constellation.com.

Constellation Energy
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Maureen Brown
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