Influence of operating parameters on the performance of combined cycle based on exergy analysis

This paper presents the energy and exergy analysis for actual data of the triple-pressure combined cycle power plant (CCPP). This study was carried out to evaluate each component's power plant efficiency and destruction rate. Furthermore, to investigate the effect of operating parameters on a combined cycle power plant using an engineering equation solver (EES) program. The result shows that the net energy and exergy efficiency is calculated at 56%and 54%, respectively. Also, by exergy analysis, the major source of exergy destruction among components occurs in the combustion chamber with a value of 314.6 MW which is 58% of the total exergy destruction in power plants. The exergy destruction was significantly affected by the increased ambient tem-perature. The heat transfer rate can be reduced with the high-pressure ratio in the gas turbine, leading to an increase in the overall efficiency. Besides that, the high turbine inlet temperature increased the steam cycle's generated power and the power plant's overall efficiency. Reducing the exergy destruction rate will increase the power output and efficiency of the combined cycle power plant. Therefore, maximum efficiency could be achieved by decreasing the ambient tem-perature and increasing the turbine inlet temperature.