Performance analysis of natural gas pressure energy utilization system based on gas turbine combined cycle power plant

Abstract Taking the SGT5-4000F gas turbine combined cycle system as the research object, a natural gas pressure energy utilization system was developed to optimize the performance of gas turbine power plants, addressing specific operational requirements. This system harnesses the residual pressure of natural gas to generate electricity while concurrently cooling the turbine inlet air, thereby improving the overall output of the combined cycle, particularly during peak electricity demand periods. Under full load conditions, the implementation of the residual pressure utilization system resulted in an increase in combined cycle power output by 8.47 MW, 7.58 MW, 7.35 MW, and 7.56 MW, respectively, when the inlet air temperature rose from 25 °C to 40 °C. Correspondingly, the efficiency of the combined cycle improved by 0.15%, 0.20%, 0.29%, and 0.39%, respectively. The total system power enhancement reached 9.48 MW, 8.63 MW, 8.42 MW, and 8.42 MW, respectively.