Injecting steam into the gas turbine has been a strategy adopted by turbine users for a long time to increase its power output. The increased mass flow coupled with the higher thermal conductivity and specific heat of the exhaust gases (due to the higher percent by volume of water vapor) generates more power in the gas turbine and higher steam output in the HRSG. The Cheng cycle, discussed later, is a good example of this technique. Besides increasing the power output, it reduces the turbine NOx levels.