Equipment and conveyor belts that used to load coal into the coal-fired Castle Gate Power Plant sits idle as the plant no longer produces electricity outside Helper, Utah August 3, 2015. The plant was closed in the Spring of 2015 in anticipation of new EPA regulations. President Barack Obama challenged America and the world to step up efforts to fight global warming on Monday at the formal unveiling of his administration's controversial, ramped-up Clean Power Plan to cut carbon emissions from U.S. power plants. REUTERS/George Frey