South Carolina's Energy Future

Affordable Clean Energy (ACE) Rule

On February 12, 2021, the EPA issued the memorandum "Status of ACE and CPP". The EPA does not expect states to take any further 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.

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.

On August 21, 2018, the U.S. Environmental Protection Agency (EPA) proposed a new rule to reduce greenhouse gas (GHG) emissions from existing coal-fired electric utility generating units and power plants across the country. This proposal, entitled the Affordable Clean Energy Rule, establishes emission guidelines for states to use when developing plans to limit GHGs at their power plants. The ACE Rule would replace the EPA’s Clean Power Plan, which has never gone into effect.

Clean Power Plan (CPP) and SC’s Public Engagement Efforts

On August 3, 2015, the U.S. Environmental Protection Agency (EPA) released the final rule on the Clean Power Plan for existing power plants under section 111(d) of the Clean Air Act (CAA).

On October 23, 2015, the EPA published a proposed federal plan and model trading rules to implement the greenhouse gas (GHG) emission guidelines (EGs) for existing fossil fuel-fired electric generating units (EGUs) under the CAA. Public comments were accepted until January 21, 2016.

On February 9, 2016, the Supreme Court of the United States issued a 5-4 ruling granting a stay to the implementation of the Clean Power Plan, pending a decision of the United States Court of Appeals for the District of Columbia Circuit on the legal merits of the rule. 

In late 2013, the EPA presented a series of questions for state regulators and the utility industry. Over the next eight months, the EPA held listening sessions and additional meetings across the country to engage stakeholders. Concurrently, DHEC began having informal discussions with various entities and individuals with the primary goal of assisting the EPA with its outreach efforts.

One of DHEC's first outreach efforts involved a listening session between South Carolina's utility stakeholders and the EPA on November 5, 2013. The discussion was centered on the series of questions posed by the EPA. Stakeholders that attended this listening session were later invited to be a part of the S.C. Energy Coalition, which grew to include representatives from the environmental conservation and environmental justice communities.

The S.C. Energy Coalition has met regularly since 2013 to share information from perspectives and areas of expertise. This proactive effort provided stakeholders the opportunity to not only gain knowledge about regulating carbon pollution under the Clean Air Act, but also the opportunity to voice concerns and provide feedback to the EPA in its development of the proposed rule. Through a stakeholder consensus process, the Energy Coalition developed a set of "guiding principles" for the EPA's consideration as it moved forward with carbon regulation under the Clean Air Act. Several partners from the coalition also submitted additional comment letters.

DHEC also held several public engagement sessions throughout the state to provide interested stakeholders information on the final rule and future opportunities for involvement.

Missed a Kickoff Engagement Session? Want to learn more about what was discussed?

Presentation materials (ORS and DHEC) (pdf)

By forming statewide, collaborative partnerships, South Carolina has taken a proactive approach in shaping these national standards. DHEC remains committed to working with all stakeholders to ensure that the development of this national ruling is done in a manner that provides maximum flexibility in development and implementation at the state level, is tailored to meet our state's unique economic challenges, and is right for South Carolina. For more information, please visit

Related Links/Additional Resources


Mary Peyton Wall, Manager, (803) 898-4064