The proposed rule, known as the Clean Power Plan, establishes a framework for states to regulate carbon dioxide (CO₂) emissions from existing coal-fired, oil-fired, and natural gas-fired power plants. The plan combines mandatory, state-specific carbon emission reduction goals with substantial flexibility, allowing states to determine how best to achieve these reductions. With a few exceptions—primarily small electricity generating units (EGUs) or facilities that do not sell a significant portion of their electricity to the grid—the Clean Power Plan applies to all fossil fuel-fired EGUs that were operating or under construction as of January 8, 2014. EGUs that have been reconstructed or significantly modified are excluded from the rule. In a separate action issued in June 2014, the U.S. Environmental Protection Agency (EPA) also proposed regulations to limit carbon dioxide emissions from these reconstructed or newly modified power plants.
