Efficiency and power enhancement of combined cycle power plants by inlet air conditioning techniques

Abstract

Paper presented at the 6th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 30 June - 2 July, 2008.The combined gas/steam turbine cycle power plants offer an efficient and environment friendly system for electric power generation. However the power output from a gas turbine decreases significantly with increase in ambient temperature. This is a serious condition especially in hot climatic environments. Best method to tackle this situation is to condition the inlet air to the gas turbine using innovative techniques for augmenting power and efficiency improvement. This paper illustrates the influence of various inlet air conditioning techniques. A computational model of the Combined Cycle Gas Turbine (CCGT) plant was developed and applied to a typical 350 MW Combined Cycle Power Plant (CCPP), operational in Kerala, India. The model is based on thermodynamics, heat transfer and psychrometric principles. With the help of this model, a parametric analysis of combined cycle gas turbine plant for various temperatures and humidity with swirl flash technology was carried out and results plotted. Evaporative cooling and refrigerated inlet cooling techniques were compared with the swirl flash technology to establish that the swirl flash is superior to other methods in efficiency and power enhancement.