The US Environmental Protection Agency (EPA) has proposed new CO₂ standards for coal and natural gas-fired power plants. The proposal for coal and new natural gas power plants would avoid up to 617 million metric tons of total CO₂ through 2042—equivalent to reducing the annual emissions of 137 million passenger vehicles, roughly half the cars in the United States.

The proposals would also result in cutting tens of thousands of tons of particulate matter (PM_2.5), sulfur dioxide, and nitrogen oxide. Through 2042, EPA estimates the net climate and health benefits of the standards on new gas and existing coal-fired power plants are up to $85 billion.

EPA says that the proposed limits and guidelines would require ambitious reductions in carbon pollution based on proven and cost-effective control technologies that can be applied directly to power plants. They also provide owners and operators of power plants with lead time and compliance flexibilities. EPA’s analysis found that power companies can implement the standards with a negligible impact on electricity prices—well within the range of historical fluctuations.

The technology-based standards EPA is proposing include:

• Strengthening the current New Source Performance Standards (NSPS) for newly built fossil fuel-fired stationary combustion turbines (generally natural gas-fired).

• Establishing emission guidelines for states to follow in limiting CO₂ emissions from existing fossil fuel-fired steam generating EGUs (including coal, oil and natural gas-fired units).

• Establishing emission guidelines for large, frequently used existing fossil fuel-fired stationary combustion turbines (generally natural gas-fired).

Based on a separate analysis, EPA is projecting the proposed standards for existing gas-fired plants and the third phase of the NSPS could achieve up to 407 million metric tons of CO₂ emission reductions. As EPA works to finalize the rulemaking, the agency will complete additional advanced modeling, aligning methodologies across the rulemaking and considering real-world scenarios within the power sector to best understand how components of the rule impact each other.

In developing these proposed carbon pollution standards, EPA considered a range of technologies including CCS, utilizing low-GHG hydrogen, and adopting highly efficient generation technologies.

Installation of controls such as CCS for coal and gas plants, and low-GHG hydrogen co-firing for gas plants are more cost-effective for power plants that operate at greater capacity, more frequently, or over longer time periods, EPA said. The proposed standards and guidelines take this into account by establishing standards for different subcategories of power plants according to unit characteristics such as their capacity, their intended length of operation, and/or their frequency of operation.

The proposal requires that states, in developing plans for existing sources, undertake meaningful engagement with affected stakeholders, including communities disproportionately burdened by pollution and climate change impacts, as well the energy communities and workers who have powered our nation for generations.