Thermo-economic analysis of combined cycle configurations with intercooling and reheating

Abstract Combined cycles have integration of different cycles for the effective utilization of heat energy. Among different measures the intercooling and reheating are the commonly used techniques for improving the performance of thermal power cycles. Here, the study of combined cycle configurations having gas turbine, steam turbine and ammonia-water turbine with intercooling and reheating has been undertaken. The present paper analyzes the different configurations of intercooled reheat gas turbine cycle based combined cycle configurations using steam and/or ammonia-water mixture as coolant to gas turbine blades for fixed design condition - turbine inlet temperature of 2000K, cycle pressure ratio 40 and ambient condition of 303K. The comparison of different configurations shows that the work output of 1789.39 kJ/kg of air is obtained. First law and second law efficiencies of 62.50% and 60.7% is maximum for triple pressure heat recovery generator having ammonia-water turbine at each pressure level. The cost of electricity production is minimum for maximum work output and corresponds to 0.06727USD/kWh.