Proposal: Affordable Clean Energy (ACE) Rule

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In June 2019, EPA i ssued the final Affordable Clean Energy rule (ACE) and repealed the Clean Power Plan.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