Typical steam turbines have efficiency up to around 50%. I think the EPA is referring to isentropic efficiency[0], which is "efficiency" compared to the theore

Typical steam turbines have efficiency up to around 50%. I think the EPA is referring to isentropic efficiency[0], which is "efficiency" compared to the theoretical maximum for the delta T involved. [0] https://en.wikipedia.org/wiki/Steam_turbine#Thermodynamics_of_steam_turbines https://en.wikipedia.org/wiki/Steam_turbine#Thermodynamics_o...