Effect of Inlet Air Refrigeration on the Performance of Combined Cycle Power Plants

In the present work an attempt has been made to study the effect of inlet air refrigeration on the performance of combined cycle power plants. The inlet air cooling for the chosen combined cycle configuration may be done by means of employing a refrigeration system such as vapor compression and vapor absorption system, which derive the energy input from the system itself. In the vapor absorption system, the input energy to generator is given by three possible heat source from the system namely from the gas turbine exhaust, steam bled from steam turbine and exhaust gas from the exit of heat recovery steam generator (HRSG). It has been observed that the vapor absorption system with HRSG exhaust as heat source to the generator is the better option followed by the vapor compression refrigeration system for compressor inlet air cooling. The cooled compressed inlet air up to 280K from 300K improves the plant specific work around 4% and plant efficiency around 0.39 percentage point for the combined cycle using vapor compression system.