Performance simulation of dual pressure HRSG in combined cycle power plant

Combined cycle power plants play an important role in the present energy sector. The main challenge in designing a combined cycle power plant is how to transfer gas turbine exhaust heat to the steam cycle to achieve optimum steam turbine output. Most of the combined cycle developers focus on the gas turbine and steam turbine, but the performance of the heat recovery steam generator (HRSG) strongly affects the overall performance of the combined cycle power plant. Therefore, the present article undertakes the problem of optimal utilization of the waste heat from gas turbine exhaust with dual pressure HRSG confi guration. The combined cycle effi ciency has been analyzed parametrically from both the first and second law of thermodynamics. It is observed that in the dual cycle the high-pressure steam pressure must be relatively high, and low-pressure steam pressure must be low for better heat recovery from HRSG.