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  2. Stationary Sources of Air Pollution

Affordable Clean Energy Rule

Announcements

May 11, 2023 - EPA proposes Greenhouse Gas Standards and Guidelines for Fossil Fuel-Fired Power Plants

March 7, 2023 - EPA is extending the due date for state plans under the Affordable Clean Energy Rule until April 15, 2024.  Because the ACE Rule's July 8, 2022 deadline passed while the rule was vacated by the D.C. Circuit, and because states had no reason to continue to work on their plans during the period when the ACE Rule was vacated, it is necessary to extend the deadline for state plan submittal.  By extending the deadline, this action makes clear the EPA does not expect states to take immediate action to develop and submit plans under Clean Air Act section 111(d) with respect to greenhouse gas emissions from power plants at this time.  This is a final rule that will be effective upon publication in the Federal Register. 

Related Proposals

Proposed Affordable Clean Energy Rule
In August 2018, EPA proposed the Affordable Clean Energy rule (ACE) to establish emission guidelines for states to develop plans to address greenhouse gas emissions from existing coal-fired electric utility generating units. 

Proposed Clean Power Plan Repeal
In October 2017, EPA proposed to repeal the Clean Power Plan because it exceeded EPA's authority.

On June 19, 2019, EPA issued the final Affordable Clean Energy rule (ACE) – replacing the prior administration’s overreaching Clean Power Plan with a rule that restores rule of law, empowers states, and supports energy diversity. The ACE rule establishes emission guidelines for states to use when developing plans to limit carbon dioxide (CO2) at their coal-fired electric generating units (EGUs). In this notice, EPA also repealed the CPP, and issued new implementing regulations for ACE and future rules under section 111(d). 

On January 19, 2021, the D.C. Circuit vacated the Affordable Clean Energy rule and remanded to the Environmental Protection Agency for further proceedings consistent with its opinion.

  • News Release
    • EPA Finalizes Affordable Clean Energy Rule, Ensuring Reliable, Diversified Energy Resources while Protecting our Environment

  • Fact Sheets
    • Overview of the Final Affordable Clean Energy Rule
    • CO2 Emissions Trends
    • Overview of the Regulatory Impact Analysis
    • Repeal of the Clean Power Plan
    • Revised CAA Section 111(d) Implementing Regulations
  • Federal Register Notice 
    • Repeal of the Clean Power Plan; Emission Guidelines for Greenhouse Gas Emissions from Existing Electric Utility Generating Units; Revisions to Emission Guidelines Implementing Regulations
    • Final Rule: Delay of Submittal Date for State Plans Required Under the Affordable Clean Energy Rule
  • Regulatory Impact Analysis
    • RIA for the Repeal of the Clean Power Plan, and the Emission Guidelines for Greenhouse Gas Emissions from Existing Electric Utility Generating Units
    • Power Sector Analysis for the final ACE rule
  • Presentation
    • Overview of ACE
  • Implementation Resources
    • ACE Implementation Frequently Asked Questions

Stationary Sources of Air Pollution

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    • National Emission Standards for Hazardous Air Pollutants (NESHAP)
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    • Good Neighbor Plan for the 2015 Ozone National Ambient Air Quality Standards
  • Small Business Assistance Program
Contact Us About Stationary Sources of Air Pollution
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on April 15, 2025
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