A Calculation and Analysis to Determine Feasibility of Inlet Air Evaporative Cooling Systems for CCPP by Thermodynamic and Economic Method

Inlet air evaporative cooling system for combined cycle power plant (CCPP) is not always feasible in all ambient conditions. In order to propose a specific quantitative indicator which is measured easily to determine the feasibility of evaporative cooling system, a calculation and analysis by thermodynamic and economic method is carried out. A new critical relative humidity (RH) evaluation method is put forward considering ambient RH, ambient temperature, payback period (PBT), electricity price and fuel price. Sensitivity analysis of the factors affecting the critical RH is also carried out. Taking Hangzhou as an example, the PBT evaluation method by section hourly integrating is put forward. Effective criteria for quantificationally evaluating the feasibility of evaporative cooling system for CCPP are provided. It is concluded that the installation of the evaporative cooling system for CCPP is feasible in Hangzhou for a 2.87-year PBT by hourly calculation and analysis. (paper)