The city of Chicago will make the largest purchase of renewable energy in the United States when it signs an agreement to purchase 20 percent of its electricity from green sources.CHICAGO, Illinois, US, 2001-06-15 [SolarAccess.com] Mayor Richard Daley says the city will sign an agreement with ComEd. The utility will provide 10 percent from green power in the first year, rising to 20 percent within five years. The total capacity required is 80 MW, enough for 80,000 homes. ComEd will purchase the power from other suppliers, starting with landfill gas and then moving to windfarms and solar PV arrays. Last summer, the city, the Chicago Transit Authority, city colleges, Chicago Park District and 48 suburban governments asked for quotations on the supply of green power. Daley says his city will buy the bulk of its electricity from Enron of Houston at an annual saving of $3 million. “In addition to providing the best value, ComEd showed it understood the city’s goal of building a local market for green power and keeping dollars in our local economy through ongoing investment and job creation,” says Daley. By the fifth year of the contract, the renewable energy will displace the annual emission of 249,151 tons of carbon dioxide, 1,884 tons of sulfur dioxide and 1,007 tons of nitrous oxides. The agreement allows up to half of the power to be derived from methane that otherwise would be released into the atmosphere from landfills. Methane is 21 times more potent than carbon dioxide as a greenhouse gas. ComEd will invest in the development of new green generation in the Chicago region. Profits from the sale of green power to the city at a premium price will go into a reinvestment fund that will attract and develop new renewable generation within the area. ComEd will administer the fund through the Environmental Resources Trust, a Washington auditing group that will track ComEd’s green purchases. The city is working with ComEd on a related project to retrofit 15 million square feet of public buildings. The utility will expand the city’s successful Greencorps Chicago program, adding the installation of energy efficient equipment to the year-long apprenticeship with the City.