Executive Summary

• This week the Trump Administration Environmental Protection Agency (EPA) finalized repeal of all Biden-era regulations on power plant greenhouse gas (GHG) emissions; this represents significant progress in repealing all such regulations, with the repeal of remaining Obama-era limits to be finalized in the months ahead.
• EPA estimates that the finalized repeal of Biden-era GHG regulations on power plants would save $310 billion in direct compliance costs, and the pending repeal of President Obama’s regulations would save an additional $370 million—these cost saving estimates are an-order-of-magnitude jump from the preliminary estimates of $9.6–$19 billion, a revision driven by soaring artificial intelligence data center energy demand, per EPA’s analysis.
• When a full repeal of all the regulations is finalized, it will be subject to substantial legal challenges across the country, which would create significant policy uncertainty for investors, energy developers, utilities, and other players in the U.S. electricity market, adding to the broad uncertainty in the current federal climate policy landscape.

Introduction

U.S. Environmental Protection Agency (EPA) Administrator Lee Zeldin announced the final repeal of the Biden Administration’s greenhouse gas (GHG) regulations on power plants on September 14, 2026, at the G20 Energy Abundance Ministerial.

This action marks significant progress toward the Trump Administration’s goal of repealing all existing U.S. GHG regulations on power plants. The remaining power plant GHG regulations from the Obama Administration are expected to be finalized as soon as next year.

EPA estimates that final repeal of Biden-era GHG regulations on power plants would save $310 billion in direct compliance costs, and the pending repeal of Obama’s regulations would save an additional $370 million. These cost saving estimates are an-order-of-magnitude jump from the preliminary estimates of $9.6–$19 billion, a revision driven by soaring artificial intelligence data center energy demand, per EPA’s analysis.

The finalized partial repeal of U.S. power plant GHG regulations will certainly be subject to substantial legal challenges across the country. When the full repeal is finalized, it will be subject to even more litigation, which would create significant policy uncertainty for players in the U.S. electricity market such as investors, energy developers, and utilities. This would add to the broad uncertainty in the current federal climate policy landscape.

Repealing Biden and Obama Regulations on Power Plants 

EPA released proposals last year seeking to repeal all existing GHG emissions regulations on U.S. power plants, including:

• The Obama Administration’s regulation issued on October 23, 2015: New Source Performance Standards (NSPS) for coal and gas power plants.
• The Biden Administration’s regulations issued on May 9, 2024: Specifically, promulgated in the Carbon Pollution Standards (CPS), NSPS for coal-fired steam generating units undertaking a large modification, and new gas power plants, as well as emission guidelines for existing coal-, oil-, and gas-fired steam generating units.

American Action Forum (AAF)’s previous insight provides a detailed overview and analysis of the agency’s proposed actions, rationale, preliminary impact estimates and the tug of war over emissions regulations on power plants between the Trump and Obama and Biden Administrations. The insight also identifies multiple problems in EPA’s preliminary impact study of the proposed repeal of the power plant GHG emission regulations.

On September 14, 2026, the Trump Administration EPA announced the final rule to repeal Biden’s GHG regulations on power plants to “unleash the full potential of America’s vast energy resources, including coal and natural gas” and stated that “Coal production for power sector use is expected to increase by more than 10 times.”

Here are the highlights of the EPA’s updated regulatory impact analysis of the final  repeal of the Biden GHG regulations:

• Dramatic Upward Revision of Cost Savings: The rule would save $310 billion dollars (in 2024 dollars) —referred to as the “reduced real resource costs paid by society as a result of this final repeal.” Notably, this is an-order-of-magnitude jump from the preliminary estimates of $9.6–$19 billion. The study attributes the revision to “significantly higher electricity demand driven primarily by data center use in applications supporting artificial intelligence, and the passage of the One Big Beautiful Bill Act.”
• Elimination of Monetized Estimates of Health Costs: While EPA confusingly labels the health cost estimates in its preliminary analysis as “PM2.5 and O₃-related health benefits” to be between -$76 billion to -$130 billion in present value, the finalized impact analysis does not provide any monetized health costs (or foregone health benefits). Instead, it lists the potential health impact in a descriptive, non-monetized way.
• Bigger CO₂ Emissions Impact: Similar to the preliminary analysis, the updated impact study does not provide any monetized costs for the carbon dioxide emissions impact caused by the partial repeal; moreover, the levels of projected emissions have been significantly revised upwards, with U.S. power plants’ CO₂ emissions projected to increase from the baseline under the Biden Administration’s CPS regulation by 20 million metric tons (MMT) in 2030, 406 MMT in 2035, 533 MMT in 2040, 486 MMT in 2045.

EPA’s Incomplete Regulatory Impact Analysis

While the repeal of the Biden Administration’s power plant regulations would save an even larger amount of compliance and administrative costs, the Trump Administration does not provide any estimates of climate costs associated with the repeal of all GHG emissions regulations on U.S. power plants.

Additionally, the EPA’s updated impact study doubles down on the issues identified in AAF’s analysis of the preliminary impact study by completely removing the monetized estimates of health costs from increased air pollutants such as PM2.5 (fine inhalable particulate matter).

Looking Forward

The finalized partial repeal of U.S. power plant GHG regulation will certainly be subject to substantial legal challenges across the country. When the full repeal is finalized, it will be subject to even more litigations, which would create significant policy uncertainty for players in the U.S. electricity market, such as investors, energy developers, and utilities. This would add to the broad uncertainty in the current federal climate policy landscape.