Who says the Ravens can't play a cleaner game?
Baltimore's professional football team is joining with **Constellation Energy** to promote renewable energy when it plays the San Francisco 49ers Thanksgiving day at M&T Bank Stadium.
Baltimore-based Constellation will retire "renewable energy certificates" that should cover the typical energy usage during the game. The certificates, which encourage wind, solar and other renewable power generation, will avoid about 30 tons of climate-altering carbon dioxide emissions - on a par with what would be produced by 1,200 tailgaters firing up propane grills.
To draw attention to the green partnership, **Constellation Energy** and the Ravens plan to stage a Facebook contest next week to test fans' football and energy knowledge. They'll be giving away a pair of tickets and two pre-game hospitality passes to the Ravens final home game on Christmas Eve. Look for it on **Constellation's Facebook page**.