** FILE ** Three windmill turbines sit atop Buffalo Mountain in Oliver Springs, Tenn., in this Sept. 18, 2000, file photo. New worries about the environment, technology advances and tax breaks extensions are empowering European wind energy companies to try their luck in the United States. The U.S. has led the world in installing new wind turbines for the past two years, but it still ranks behind Germany and Spain in wind power production. (AP Photo/Wade Payne, file)