Environmental Protection Agency (EPA) Administrator Gina McCarthy (C) laughs after announcing steps under the Clean Air Act to cut carbon pollution from existing power plants during a news conference in Washington June 2, 2014. The U.S. power sector must cut carbon dioxide emissions 30 percent by 2030 from 2005 levels, according to federal regulations unveiled on Monday that form the centerpiece of the Obama administration's climate change strategy. REUTERS/Joshua Roberts (UNITED STATES - Tags: POLITICS ENERGY ENVIRONMENT)