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  2. Stationary Sources of Air Pollution

Proposal: Affordable Clean Energy (ACE) Rule

Related Actions

Affordable Clean Energy Rule and Repeal of the Clean Power Plan
In June 2019, EPA issued the final Affordable Clean Energy rule (ACE) and repealed the Clean Power Plan. 

Advance Notice of Proposed Rulemaking
In December 2017, EPA issued an Advance Notice of Proposed Rulemaking (ANPRM) to solicit information from the public about a future rulemaking to limit greenhouse gas emissions from existing electric utility generating units (EGUs).

On August 21, 2018, the U.S. Environmental Protection Agency proposed the Affordable Clean Energy rule (ACE) which would establish emission guidelines for states to develop plans to address greenhouse gas emissions from existing coal-fired power plants. ACE would replace the 2015 Clean Power Plan, which EPA has proposed to repeal because it exceeded EPA's authority. The Clean Power Plan was stayed by the U.S. Supreme Court and has never gone into effect.

ACE has several components: a determination of the best system of emission reduction for greenhouse gas emissions from coal-fired power plants, a list of “candidate technologies” states can use when developing their plans, a new preliminary applicability test for determining whether a physical or operational change made to a power plant may be a “major modification” triggering New Source Review, and new implementing regulations for emission guidelines under Clean Air Act section 111(d). 

  • Press Release: EPA Proposes Affordable Clean Energy (ACE) Rule
  • Fact Sheets
    • Overview of the proposed ACE rule
    • CO2 emissions trends
    • Costs and benefits 
    • Legal overview
    • Permitting improvements under New Source Review program
    • Side-by-side comparison of ACE and CPP
  • Federal Register Notice: Affordable Clean Energy rule proposal
  • Regulatory Impact Analysis: Affordable Clean Energy rule proposal RIA
    • Power Sector Analysis of the proposed ACE rule
  • Public Hearing
    • EPA held a public hearing on the Affordable Clean Energy (ACE) rule proposal on Monday October 1, 2018, from 9:00 a.m.-8:00 p.m. at the Ralph H. Metcalfe Federal Building, 77 West Jackson Boulevard, Chicago, Illinois.​ 
    • Read the Federal Register Notice for more details. The preliminary speaker list is posted below.  

      • Public Hearing on the Proposed ACE Rule: Preliminary Speakers List (4 pp, 98K, About PDF)

Stationary Sources of Air Pollution

  • Stationary Sources of Air Pollution Home
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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 About Stationary Sources of Air Pollution to ask a question, provide feedback, or report a problem.
Last updated on November 18, 2024
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