Clean Power Plan

FACT SHEET: Proposal to Limit Carbon Pollution from Modified and Reconstructed Power Plants

CARBON POLLUTION STANDARDS


Power plants are the largest stationary source of this harmful pollution in the United States -- about one-third of all greenhouse gas pollution comes from the generation of electricity by power plants.

  • On June 2, 2014, EPA proposed standards to address carbon dioxide (CO2) emissions from modified and reconstructed power plants.
     
  • This action is one of three separate but related proposals to address carbon pollution from power plants.
    • The proposed Carbon Pollution Standards for newly constructed power plants are set under the authority of Clean Air Act Section 111(b). They were announced in September 2013 and published in the Federal Register in January 2014.
       
    • The proposed Carbon Pollution Standards for modified and reconstructed power plants are also set under the authority of Clean Air Act Section 111(b).  They were announced in June 2014.
       
    • The proposed Clean Power Plan for existing power plants is issued under the authority of Section 111(d). It was announced in June 2014.
       
  • The proposed Carbon Pollution Standards for modified and reconstructed power plants would only apply to a unit that meets certain, specific conditions described in the Clean Air Act and implementing regulations for being “modified” or “reconstructed.”
     
  • A modification is any physical or operational change to an existing source that increases the source’s maximum achievable hourly rate of air pollutant emissions.
     
  • A reconstructed source is a unit that replaces components to such an extent that the capital cost of the new components exceeds 50 percent of the capital cost of an entirely new comparable facility. 
     
  • The proposed emission limits for modified or reconstructed sources are based on the performance of available and demonstrated technology.  These proposed limits for modified and reconstructed sources do not require implementation of carbon capture and storage (CCS) technology, nor are they based on that technology.
     
  • The EPA is proposing separate numeric standards for different types of units.
    • For affected modified fossil fuel-fired electric utility steam generating units (utility boilers and integrated gasification combined cycle (IGCC) units), the EPA is co-proposing two alternative standards of performance. Under the first alternative, all modified units would be subject to a single standard of performance. In the second co-proposed alternative, the EPA is proposing that the specific form of the standard will depend on whether the source makes the modification before or after becoming subject to a CAA section 111(d) state plan. This alternative recognizes that actions taken to comply with a Clean Air Act (CAA) section 111(d) state plan may result in improved performance at the source. In all cases the level of the proposed standards is based on a combination of best operating practices and equipment upgrades.
       
    • For affected modified natural gas-fired stationary combustion turbines, the agency is proposing standards of performance set at a level based on efficient Natural Gas Combined Cycle (NGCC) technology. These standards would be applicable whether or not a unit is subject to a section 111(d) state plan. 
       
    • For affected reconstructed fossil fuel-fired electric utility steam generating units (utility boilers and integrated gasification combined cycle units), and for affected reconstructed natural gas-fired stationary combustion turbines, the EPA is proposing standards of performance based on the most efficient generating technology that is applicable to each category of units. This standard would not be affected by the submittal of a CAA section 111(d) state plan.

Printable version of the fact sheet:

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