The biggest and newest of three wind turbines at F.E. Warren Air Force Base, Wyoming faces the wind coming across the high plains and push against the clouds that later brought dropped a few inches of snow on the base and surrounding city of Cheyenne on April 6, 2010. The larger wind turbine was completed and online early in 2009 and is rated at 2 mega watts of electrical energy that goes directly into the base power grid. The other two produces a combined output of 1.3MW. From most points on the base the wind turbines can be seen. At its base the blades make a low whoosh sound. (U.S. Air Force photo/Lance Cheung)