EPA delivers carbon emission reductions from power plants, but work remains
EPA recently finalized carbon pollution standards for existing coal and new gas-fired power plants as required under the Clean Air Act. The final rule will lead to more carbon emissions reductions from these sources than EPA’s initial proposal estimated, by including recommendations from Clean Air Task Force (CATF) and our partners at the Natural Resources Defense Council (NRDC).
But the work is not done. Previous greenhouse gas emission rules have faced legal challenges, and these will likely be no exception. And states over the next two years — working with power plant operators and communities — will develop plans to implement the requirements for existing coal plants. Finally, EPA must fulfill its commitment and Clean Air Act obligation to regulate existing gas-fired power plants, a significant and growing portion of power sector carbon emissions.
CATF’s advocacy led to stronger standards for greater emissions reductions
While the proposed rule was a step in the right direction, we knew it needed to be strengthened to achieve greater emissions reductions. We drew upon technical analyses and sector expertise at CATF and with partners to recommend improvements to the proposed performance standards and emission guidelines, several of which EPA adopted.
For new baseload gas-fired power plants, the final performance standard is based on a 90% capture rate through carbon capture and storage technology, starting in 2032, three years sooner than had been proposed. While the final performance standard is based on what can be achieved by applying carbon capture and storage, rather than on the proposed dual best systems of emission reduction of carbon capture and storage or low-greenhouse gas hydrogen co-firing,1 hydrogen co-firing remains a compliance option for individual sources (as do other methods of achieving the final emissions limits).
EPA also adopted our recommendation to lower the annual capacity factor for plants covered by this standard to 40% — meaning that it will apply to all plants that are producing power equivalent to running at their base load rating for at least 40% of all the hours in the year. This change will result in over 10 million metric tons of additional emission reductions per year.
The final rule also includes additional carbon emission reductions for coal-fired plants. Long-lived coal plants will have to meet an emissions limit that was set based on what can be achieved by applying 90% carbon capture and storage. In the final rule, EPA also moved up the operation date cutoff for these sources from 2040 to 2039. Changing this date will prevent a full year of unabated coal emissions. The rule will also provide greater certainty to planners through enforceable dates by which plants must cease operations if they choose not to meet the emission limit.
Attention now turns to states for implementation
Once the final emission guidelines for existing coal-fired power plants are published in the Federal Register, states will have two years to develop and submit state-specific plans to EPA for review and approval. Some states have no or very few operating coal plants, and their state planning efforts will be narrower in scope. While others have more coal plants to address within their state plans, only a small fraction of plants are anticipated to operate in 2039 and beyond even without the power plant rule; therefore, state planning for compliance with the most stringent provisions of the rule likely will be limited.
Once a complete state plan is submitted, EPA will have one year to take action on the plan and can approve, disapprove, partially approve and partially disapprove, or approve with conditions. At its core, a state plan establishes the standard of performance for each unit within the state subject to the emission guideline and governs implementation and enforcement of the standards. If a state chooses not to submit a plan, EPA will develop a federal plan to cover affected units in that state.
Already, some states have announced plans to bring legal challenges to EPA’s long-awaited power plant carbon pollution standards. The final performance standards and emission guidelines are based on a strong technical record, including the technical studies and data CATF provided the agency in our comments, and EPA acted consistent with its Clean Air Act authority as interpreted by the Supreme Court. CATF is ready to defend this rule in court against any such attacks.
EPA must work expeditiously to finalize emissions standards for existing gas
At the end of February, EPA announced it would not finalize the emission guidelines for existing gas-fired power plants it had proposed alongside the existing coal and new gas carbon pollution requirements. Instead, the agency announced a new stakeholder process intended to obtain feedback on how to comprehensively cover the entire existing gas-fired fleet pursuant to a multi-pollutant regulatory approach, such as by promulgating standards for toxic and criteria pollutants in addition to carbon. EPA then published a non-regulatory docket seeking public input on its multi-pollutant strategy through May 28, 2024.
In the final rule, EPA acknowledged existing gas makes up a “growing portion” of power sector emissions and that it is “vital” to cover these sources. CATF has urged EPA to quickly finalize strong emission guidelines for existing gas plants, and we already have provided pathways for EPA to achieve greater emission reductions from these sources at an even lower cost than EPA originally estimated. We will continue to participate in the rulemaking process to advocate for ambitious, durable emission reductions.
1 EPA proposed two best system of emission reduction pathways for new baseload combustion turbines: application of carbon capture and storage by 2035 or co-firing low-GHG hydrogen beginning in 2032 and increasing in magnitude by 2038.
