The Davis-Beese nuclear power station cooling tower is seen near Oak Harbor, Ohio February 11, 2010. Ohio-based power company FirstEnergy Corp., which operates the Davis-Beese facility, will buy Pennsylvania's Allegheny Energy Inc. in an all-stock deal worth $4.7 billion that would create one of the nation's largest utilities. REUTERS/Aaron Josefczyk (UNITED STATES - Tags: ENVIRONMENT ENERGY BUSINESS IMAGES OF THE DAY)