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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.

ACE rule implementation

Affordable Clean Energy rule

On June 19, 2019, the U.S. Environmental Protection Agency (U.S. EPA) finalized the Affordable Clean Energy (ACE) rule, which establishes emissions guidelines for states to use when developing plans to limit carbon dioxide (CO2) at their existing coal-fired electric utility generating units (EGUs) and associated state plan requirements under Section 111(d) of the Clean Air Act. The rule and supporting materials can be found on U.S. EPA's Affordable Clean Energy rule webpage.

Wisconsin EGUs subject to ACE rule

Under the ACE rule, a designated facility subject to this regulation is any coal-fired EGU that meets all of the following criteria:

  1. commenced construction on or before January 8, 2014;
  2. serves a generator connected to a utility power distribution system capable of selling greater than 25 megawatts (MW) of electricity;
  3. has a base load rating greater than 250 million British thermal units per hour (mmBtu/hr) heat input of fossil fuel (either alone or in combination with any other fuel); and
  4. burns coal for more than 10.0 percent of the average annual heat input during the three previous calendar years.

The following 14 EGUs at eight power plants in Wisconsin meet these criteria:

Facility name FID City WI Unit ID
Columbia Energy Center 111003090 Pardeeville B21; B22
Edgewater Generating Station 460033090 Sheboygan B25
Elm Road Generating Station 241007690 Oak Creek B18; B19
Genoa Generating Station 663020930 Genoa B20
John P Madgett Station 606034110 Alma B25
Manitowoc Public Utilities Power Plant 436035930 Pardeeville B09
Oak Creek Power Plant 241007690 Oak Creek B25; B26; B27; B28
Weston Power Plant 737009020 Kronenwetter B03; B04

Notes:

  • Manitowoc unit B08 is permitted at less than 25 MW so is not subject to the ACE rule.
  • On 1/23/2020, Dairyland Power Cooperative announced a plan to shut down Genoa Generating Station in mid- to late-2021.

Developing Wisconsin’s state plan

The ACE rule requires states to submit state plans that set standards of performance for each designated facility to U.S. EPA no later than July 8, 2022. DNR requested utilities with designated facilities submit the necessary permit applications proposing a standard of performance for each designated facility, including the proposed emission performance rate(s), and an analysis supporting the proposal. DNR plans to issue these permits by February 2022, following the required permit review, public comment, and issuance process. The final permits will be a critical element of the state plan submitted to U.S. EPA.

Public meetings

Utility permit application checklist

DNR has developed a checklist to assist utilities in providing a complete analysis that meets ACE rule regulatory requirements. The checklist focuses on the unit-level information and analyses for each designated facility needed to satisfy the heat rate improvement assessment and emission performance rate requirements set forth in the ACE rule.

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