A home game at Soldier Field can eat up a lot of energy. Thestadium alone emits as much carbon dioxide as nearly 400 cars. This autumn, theChicago Bears are looking to offset this energy use with a new campaign and anew electricity supplier.The Chicago Bears Football Club Inc. teamed up withConstellation Energy for the team’s first environmentally friendly game, whichwill be Nov. 20 at Soldier Field. This is the first step in the launch of the Bears’ “Save DaPlanet” program, which will have more components in the future, according toScott Hagel, Chicago Bears spokesman.Constellation Energy, the retail business of ConstellationEnergy Group in Baltimore, will apply renewable energy credits already in itsportfolio to offset the stadium’s carbon footprint for a typical game, which isabout 42 metric tons of carbon dioxide emissions.“We are able to apply those against power consumption thatis not entirely renewable,” said Bruce Stewart, chief marketing officer ofretail energy for Constellation Energy.Renewable energy credits are considered a kind of currencyin energy markets and represent the environmental and non-power attributes ofrenewable energy generation. Constellation Energy both purchases the creditsand generates them directly through its wind farms. The credits can then bepurchased by businesses to meet environmental regulations.The company will also directly supply energy to Halas Hallin Lake Forest, which houses the Bears’ offices and practice facilities. Thisis the first time that Soldier Field has partnered with Constellation Energyfor both the renewable energy credits and the electricity supply of Halas Hall.“We are very conscious of what our carbon footprint lookslike and trying to do our best with trying to be resourceful,” Hagel said.“This is one way for us to partner with someone and bring this attention to notonly our organization, but also our fans.”Constellation Energy is one of about 15 alternative retailelectric suppliers in Illinois that offers competitive rates for residentsserved by the Commonwealth Edison and Ameren Corp. energy companies. It is alsothe current energy supplier for Wrigley Field.