Efficiency Enhancement of Gas Turbine Power Output by Cooling Inlet Air

Abstract

Electrical power generation can be achieved through many means, one of which includes using a gas turbine. Gas turbine performance is highly dependent on ambient temperature; as temperature increases gas turbine power output is lessened. This can be a huge problem in warmer regions like Nigeria. Gas turbines use the surrounding air to generate electricity and this gives rise to a method or curbing the effect of high ambient temperatures. Once the volumetric rate is constant as is the case in a gas turbine system, air density and ambient temperature are inversely proportional; this allows mass flow rate to be inversely proportional to temperature. To fully take advantage of this, there are many methods that can be implemented to achieve this cooling effect. A few of these methods were investigated in this study to determine their strengths and susceptibilities. The performance characteristics were scrutinised for a range of operational values including ambient temperature, humidity and air density. The results showed that air cooling significantly improved the power output of the gas turbine. At standard temperature of 32oc, the base case was 37.87 MW while evaporative cooler, mechanical and absorption chillers were 37.70 MW, 40.39 MW and 41.07 MW respectively.