The utility installed its first new pole-top transformer with soy oil insulation fluid instead of commonly used petroleum-based mineral oil near Mokena, Illinois. On an annual basis, ComEd plans to buy about 4,000 of the transformers, becoming the fourth largest purchaser of them in the country. They will be installed where construction is required for new customers on ComEd's distribution system and when overhead transformers need to be replaced.

"We are reducing the impact of our operations on the environment while maintaining our commitment to safe and reliable service," said Michael McMahan, ComEd vice president of Engineering and Project Management. "Soy oil is from a renewable resource -- soybeans. And unlike mineral oil, soy oil is almost 100 percent biodegradable."

The use of soy oil is part of a comprehensive environmental strategy to reduce greenhouse gas emissions and lower the carbon footprint of Exelon, its subsidiaries and customers.

ComEd is launching a yearlong "12 Ways to Green" campaign this month to help raise awareness among customers about energy efficiency and other environmental initiatives. ComEd is reducing its climate impact through a variety of other initiatives including using hybrid vehicles and vehicles that run on alternative fuels, reducing energy consumption at its facilities, and recycling.

Cuts carbon footprint by more than 5,500 tons

Cooper Power Systems estimates ComEd will reduce annual carbon dioxide emissions by more than 5,500 tons per year by using overhead transformers with soy oil insulation fluid, compared to using petroleum-based mineral oil. With this new commitment, ComEd will eliminate the need for about 111,000 gallons of petroleum-based mineral oil per year. ComEd first began using soy oil in 2002 in underground transformers and in building vault transformers.

Transformers with soy oil expected to last longer, save money

Cooper Power Systems says testing has shown the fluid will increase the useful life of transformers. This enhanced transformer performance combined with its more environmentally desirable profile may provide cost-saving opportunities and improve electric service reliability.

Illinois soybean farmers to benefit

The amount of soy oil needed to fill 4,000 of these transformers will require the harvesting of about 50,000 bushels of soybeans from farmers in the region. Illinois ranked number two in soybean production in the nation in 2007.

"Our standard transformers operate safely and efficiently, but we are always looking for ways to improve our performance," said McMahan. "We've been using soy oil in transformers mounted on the ground and in vaults for several years and have experienced good operational performance. We hope these new overhead transformers will not only provide environmental and safety benefits, they will result in fewer outages for our customers."

SOURCE ComEd