Nitrogen Oxide Emission Limits for New Stationary Combustion Turbines

Combustion turbine type Combustion turbine heat input at peak load (HHV) NO X emission standard New turbine firing natural gas, electric generating ≤50 MMBtu/h 42 ppm at 15 percent O 2 or 290 ng/J of useful output (2.3 lb/MWh). New turbine firing natural gas, mechanical drive ≤50 MMBtu/h 100 ppm at 15 percent O 2 or 690 ng/J of useful output (5.5 lb/MWh). New turbine firing natural gas >50 MMBtu/h and ≤850 MMBtu/h 25 ppm at 15 percent O 2 or 150 ng/J of useful output (1.2 lb/MWh). New, modified, or reconstructed turbine firing natural gas >850 MMBtu/h 15 ppm at 15 percent O 2 or 54 ng/J of useful output (0.43 lb/MWh). New turbine firing fuels other than natural gas, electric generating ≤50 MMBtu/h 96 ppm at 15 percent O 2 or 700 ng/J of useful output (5.5 lb/MWh). New turbine firing fuels other than natural gas, mechanical drive ≤50 MMBtu/h 150 ppm at 15 percent O 2 or 1,100 ng/J of useful output (8.7 lb/MWh). New turbine firing fuels other than natural gas >50 MMBtu/h and ≤850 MMBtu/h 74 ppm at 15 percent O 2 or 460 ng/J of useful output (3.6 lb/MWh). New, modified, or reconstructed turbine firing fuels other than natural gas >850 MMBtu/h 42 ppm at 15 percent O 2 or 160 ng/J of useful output (1.3 lb/MWh). Modified or reconstructed turbine ≤50 MMBtu/h 150 ppm at 15 percent O 2 or 1,100 ng/J of useful output (8.7 lb/MWh). Modified or reconstructed turbine firing natural gas >50 MMBtu/h and ≤850 MMBtu/h 42 ppm at 15 percent O 2 or 250 ng/J of useful output (2.0 lb/MWh). Modified or reconstructed turbine firing fuels other than natural gas >50 MMBtu/h and ≤850 MMBtu/h 96 ppm at 15 percent O 2 or 590 ng/J of useful output (4.7 lb/MWh). Turbines located north of the Arctic Circle (latitude 66.5 degrees north); turbines operating at less than 75 percent of peak load; modified and reconstructed offshore turbines; and turbines operating at temperatures less than 0 °F ≤30 MW output 150 ppm at 15 percent O 2 or 1,100 ng/J of useful output (8.7 lb/MWh). Turbines located north of the Arctic Circle (latitude 66.5 degrees north); turbines operating at less than 75 percent of peak load; modified and reconstructed offshore turbines; and turbines operating at temperatures less than 0 °F >30 MW output 96 ppm at 15 percent O 2 or 590 ng/J of useful output (4.7 lb/MWh). Heat recovery units operating independent of the combustion turbine All sizes 54 ppm at 15 percent O 2 or 110 ng/J of useful output (0.86 lb/MWh). Combustion turbines bypassing the heat recovery unit firing natural gas >50 MMBtu/h 25 ppm at 15 percent O 2 or 150 ng/J of useful output (1.2 lb/MWh). Temporary turbine firing natural gas ≤850 MMBtu/h 25 ppm at 15 percent O 2 or 150 ng/J of useful output (1.2 lb/MWh). Temporary turbine firing fuels other than natural gas ≤850 MMBtu/h 74 ppm at 15 percent O 2 or 460 ng/J of useful output (3.6 lb/MWh). [91 FR 43565, July 16, 2026]