EPA proposes stricter NOx standards for combustion turbines

The U.S. Environmental Protection Agency (EPA) has unveiled a proposal to tighten nitrogen oxides (NOx) emissions standards for new, modified, and reconstructed stationary combustion turbines. Announced on 22 November 2024, the initiative aims to reduce harmful air pollution, particularly for communities near power plants and industrial facilities, while ensuring affordable and reliable energy delivery.

NOx emissions are known contributors to respiratory illnesses, asthma, and smog formation. The EPA’s proposed New Source Performance Standards (NSPS) will require large stationary turbines to adopt advanced emission reduction systems, such as selective catalytic reduction (SCR) technology, alongside combustion controls.

“These stronger standards are necessary to better protect nearby communities’ health,” said Joseph Goffman, EPA assistant administrator for Air and Radiation.

The EPA estimates that by 2032, the proposed rule could reduce NOx emissions by up to 2,659 tonnes annually. With societal benefits valued at $340 million, the regulation also promises improved health outcomes for vulnerable populations, including children and the elderly.

Tailored standards for diverse applications

The NSPS considers variations in turbine sizes, operational loads, and fuel types. Proposed categories include:

• Large Turbines: Base load heat input exceeding 850 MMBtu/h (~85 MW).
• Medium Turbines: Between 250 and 850 MMBtu/h (~25 MW to ~85 MW).
• Small Turbines: Up to 250 MMBtu/h (~25 MW).

These categories allow the EPA to impose tailored standards for specific operating conditions, ensuring cost-effectiveness while maintaining environmental protection.

Next steps

Public comments will be accepted for 90 days following publication in the Federal Register. The EPA encourages stakeholders to participate in refining these standards to support cleaner energy production without compromising operational efficiency.

For more details, visit the EPA’s New Source Performance Standards (NSPS) webpage.