Modeling and optimization of a dual fuel combined cycle power plant using energy and exergy analysis: a case study

Papers dealing with any aspect of mechanical In this work, the energy and exergy evaluation of an actual dual fuel combined cycle power plant (Khoy power plant) having two dual pressure heat recovery steam generators (HRSGs) are performed. An attempt has been made to provide a model to improve the efficiency of the plant using a thermodynamic model. The thermodynamic model is developed using ASPEN PLUS software. The effects of compressors pressure ratio, gas turbines inlet temperature, condenser working pressure, high pressure steam turbine inlet pressure and high pressure and low pressure superheaters outlet temperatures are examined, and an optimal design of the power plant is presented. For this purpose, the energy and exergy efficiencies of the actual plant and those of the optimized model are calculated and compared. Exergy efficiency is determined by calculating the exergy destructions. The results indicated that the energy and exergy efficiencies increased by 8.75% and 22.04%, respectively, indicating the superiority of the optimized power plant over the actual one.