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Power Plant Carbon Emission Standards

The U.S. Environmental Protection Agency (EPA) has undertaken several rulemakings regulating carbon emissions from power plants under two sections of the Clean Air Act (CAA).

  1. Section 111(b) is a federal program that establishes emissions standards for new, modified and reconstructed stationary sources.
  2. Section 111(d) is a state-based program for existing stationary sources where the EPA establishes guidelines and the states design programs to achieve the needed emissions reductions.

Existing power plants

Final EPA rule (June 2019)

On June 19, 2019, the EPA finalized emission guidelines to limit greenhouse gas emissions from coal-fired electric generating units (EGUs). The rule and supporting materials can be found on EPA's Affordable Clean Energy Rule webpage.

Proposed EPA rule (August 2018)

On Aug. 21, 2018, the EPA proposed emission guidelines to limit greenhouse gas emissions from EGUs. The DNR and Public Service Commission of Wisconsin (PSCW) submitted comments to the EPA on this proposal on Oct. 31, 2018.

Advance notice of proposed rulemaking (December 2017)

On Dec. 28, 2017, in an Advance Notice of Proposed Rulemaking (ANPRM), the EPA described how it was considering proposing emission guidelines to limit greenhouse gas emissions from EGUs in light of the agency's proposed repeal of the Clean Power Plan final rule.

Final EPA rule (August 2015)

The EPA's regulation of carbon emissions from existing fossil-fuel power plants is known as the Clean Power Plan. The EPA finalized the Clean Power Plan on Aug. 3, 2015, but proposed repealing the rule on Oct. 16, 2017. Information about the EPA's actions related to the Clean Power Plan can be found on EPA's website [exit DNR].

On Dec. 22, 2015, the DNR and the Public Service Commission of Wisconsin (PSCW) requested that the EPA reconsider its final rule.

In the final rule, the EPA introduced the Clean Energy Incentive Program (CEIP), an optional program that states may use to incentivize early investments in wind and solar power generation, as well as energy efficiency measures in low-income communities. On Dec. 15, 2015, the DNR and PSCW submitted comments to the EPA on the CEIP.

Proposed federal plan for the Clean Power Plan (August 2015)

On Aug. 3, 2015, the EPA proposed a federal plan for the Clean Power Plan that will also serve as a model rule for states developing state plans. Information about the proposal can be found on the EPA's Clean Power Plan for Existing Power Plants [exit DNR].

On Jan. 21, 2016, the DNR and PSCW submitted comments to the EPA on the proposed federal plan.

Proposed EPA rule (June 2014)

The EPA proposed carbon pollution standards for existing power plants on June 2, 2014. The proposed rule and supporting materials can be found on the EPA's Clean Power Plan Proposed Rule [exit DNR].

The DNR and PSCW submitted two sets of comments to the EPA related to the proposed Clean Power Plan on Dec. 1, 2014.

EPA call for comments (September 2013)

On Sept. 23, 2013, the EPA issued a call for comments to states and other stakeholders [PDF exit DNR] to provide input into the development of carbon pollution standards for existing power plants. On Dec. 13, 2013, the DNR and PSCW submitted comments to the EPA in response to this request.

New, modified and reconstructed power plants

Proposed EPA rule revision (December 2018)

On Dec. 6, 2018, the EPA proposed revisions to the New Source Performance Standards (NSPS) for greenhouse gas emissions from new, modified and reconstructed power plants finalized in 2015. Proposed revisions and associated technical information can be found on EPA's Proposal: NSPS for GHG Emissions from New, Modified, and Reconstructed EGUs webpage.

On March 8, 2019, the DNR submitted technical comments to the EPA on the proposed changes to the rule.

Final EPA rule (August 2015)

On Aug. 3, 2015, the EPA finalized standards to reduce carbon emissions from new, modified and reconstructed power plants. These standards apply to new sources built after Jan. 8, 2014, and existing units that are modified or reconstructed as defined by the Clean Air Act and implementing regulations. The EPA established separate standards for two types of fossil-fuel fired sources:

  • stationary combustion turbines, which are generally fueled by natural gas; and
  • electric utility steam generating units, which are generally fueled by coal.

The EPA's final rule and associated technical information can be found on the EPA's Carbon Pollution Standards for New, Modified and Reconstructed Power Plants [exit DNR].

On Dec. 22, 2015, the DNR and the Public Service Commission of Wisconsin (PSCW) requested that the EPA reconsider its final rule.

Proposed EPA rules (2012-2014)

The EPA proposed carbon pollution standards for new and modified/reconstructed power plants in two separate actions.

Proposed EPA rule for modified/reconstructed power plants (June 2014)

On June 2, 2014, the EPA issued a proposed carbon emission standard for modified and reconstructed power plants [exit DNR].

On Oct. 16, 2014, the DNR submitted comments on the proposed rule.

Proposed EPA rules for new power plants (March 2012 and September 2013)

The EPA issued a proposed carbon pollution standard for new power plants (New Source Performance Standard, or NSPS) on March 27, 2012. In response to the comments received on this proposal, the EPA made substantial revisions to the original proposal and issued a new proposal on Sept. 20, 2013. Both proposals can be found on the EPA's Carbon Pollution Standards for New, Modified and Reconstructed Power Plants [exit DNR].

Wisconsin submitted comments in response to both proposed NSPS regulations.

Comments on the revised proposal
Comments on the initial proposal