Exergy-based sustainability analysis of combined cycle gas turbine plant integrated with double-effect vapor absorption refrigeration system

The implementation of inlet air cooling in combined cycle gas turbine (CCGT) plant is imperative to mitigate the adverse consequences, such as reduced performance, caused by high ambient temperatures. Therefore, this paper presents a novel idea of integration of the CCGT plant and a double-effect water-LiBr vapor absorption refrigeration system for inlet air cooling. The absorption system utilizes the waste heat of CCGT exhaust gas to cool the ambient air at the compressor's inlet. The objective of this paper is to compare the energy, exergy, and sustainability factors of an integrated system to that of the standalone CCGT plant. This novel approach has improved the thermodynamic performance and environmental sustainability of the integrated system. Subsequently, the energy analysis reveals that maximum improvements in work output and thermal efficiency of 5.04% and 1.64%, respectively, have been reported. Furthermore, the results show that as the ambient temperature rises, the work output of the standalone CCGT system decreases faster than that of the integrated CCGT system. Also, the integrated plant is more exergetically efficient. The maximum yield in exergetic efficiency and total work output is observed at the degrees of cooling of 8 K and 18 K, respectively. Therefore, this system can be operated suitably within this range of degrees of cooling. Besides, the exergy-based sustainability indicators are found to be improved. The environmental sustainability index has increased by up to 3.52%, showing improved fuel utilization. This also indicates that, for the same amount of emissions, the integrated CCGT plant generates more power.