A comparative and critical review on gas turbine intake air pre-cooling strategies

Intake air with a high temperature on hot days into the compressor of gas turbine (GT) power plants would not only increase the NOx emissions of the turbine but also significantly reduce the output power and thermal efficiency of the plant. Power reduction of the plant is coincident with higher electricity demand (usually because of peak application of air conditioning systems on hot days), which further aggravates the working condition of the power plant. That is why employment of an air pre-cooling technology is favorable on hot days of the year. This paper presents a comprehensive review, offering a comparative and critical discussion of pre-cooling strategies of GT power plants from different viewpoints. Absorption refrigeration (AB), Direct evaporative cooling (DE), Fogging system, Indirect evaporative cooling (IEC), Vapor compression refrigeration (VC), Air-earth heat exchanger (AEHE), Iced thermal energy storage (ITES), Turbo-expander system (TE), Liquefied natural gas system (LNG), hybrid systems and so on have been proposed before as pre-cooling technologies for GT power plant intake air, all of which are discussed in this research taking into account the region climate conditions, type of GT (single, combined cycle, micro) and other effective factors. The potential strengths and weaknesses are clarified for different applications and finally, propositions, current research gaps and future research directions are provided.