Improvement of gas turbine performance based on inlet air cooling systems: A technical review

Abstract

Performance of a gas turbine is mainly depends on the inlet air temperature. The power output of a gas turbine depends on the flow of mass through it. This is precisely the reason why on hot days, when air is less dense, power output falls off. A rise of 1°C temperature of inlet air decreases the power output by 1%. The aim of this paper is to review up to date techniques that were developed to cool inlet air to gas turbine. The techniques including the mechanical chillers, media type evaporative coolers and absorption chillers have been reviewed. It is found that the power consumption of the cool inlet air is of considerable concern since it decreases the net power output of gas turbine. In addition, the mechanical chiller auxiliary power consumption is very high compared to media type evaporative coolers. Furthermore, the reviewed works revealed that the efficiency of evaporative cooler largely depends on moisture present in the air. The gas turbine power augmentation through inlet air chilling is effectively used to boost power during high ambient temperature usually synchronous with on-peak power generation, allowing levelling of gas turbine power output. Key words: Gas turbine, absorption cooler, evaporative cooler, chiller.