BALTIMORE, MD — The City of Baltimore has agreed to purchase almost 4 percent of its annual electricity use from a new solar power generating plant to be built by Constellation Solar, a subsidiary of Exelon.

The 15-year agreement means Baltimore gets clean electricity at a price below current and projected future market rates. The Office of Sustainable Energy, part of the Baltimore City Department of Public Works, estimates a savings of $13 million over the life of the contract.

An agreement approved by the City’s Board of Estimates on July 22 calls for the City to purchase all of the electricity to be produced by Constellation, on land leased by the City, at its Perryman Station property in Harford County. Construction of the 10 megawatt (MW) solar photovoltaic power generating system is scheduled for completion by the end of 2015.

The facility will generate more than 13 million kilowatt hours of electricity in its first year; enough to provide 3.7 percent of the City’s annual electricity use, or enough to power more than 1,200 homes. The Office of Sustainable Energy is continuing to look for other opportunities to generate clean energy in and for Baltimore City.

The solar project is part of the package of commitments Exelon made in its 2012 merger with Constellation. As part of its agreement, Exelon is developing 285 to 300 megawatts of new generation in Maryland, including 125 megawatts of wind and solar energy. Exelon is the largest producer of carbon-free energy in Maryland and an active developer of new sources of clean energy in the region. Constellation is the leading commercial solar developer in Maryland with 50 MWs of generation in operation or under development in the state.

Constellation is also developing other project in Baltimore and throughout Maryland, including its future headquarters building in Harbor East and solar installations in two Baltimore City charter schools.