Recovering waste heat of a solar hybrid power plant using a Kalina cycle and desalination unit: A sustainability (emergo-economic and emergo-environmenal) approach

Abstract One of the most critical issues in configuration selection, design, and optimization of energy systems is access to an efficient system considering all the sustainability limitations. Therefore, in this paper, three scenarios for utilizing the waste heat from a solar gas turbine power plant with a sustainability approach have been investigated. In these scenarios, the waste heat is used as a heat source of a Kalina cycle, a multi-effect water desalination (MED) unit, and combined Kalina/MED, respectively. For the analysis of these scenarios, the thermodynamic modeling is performed, and in the next step, emergo-economic and emergo-environmenal analysis is performed. To evaluate the modeling, the results have been verified using other researches. Based on the mentioned modeling methods, the considered scenarios have been compared with each other from different aspects, and the best configuration has been selected. In the final step, the multi-objective optimizations were performed to maximize energy efficiency, monetary performance, and ecological performance of the proposed cycles. For optimization, a robust optimization algorithm, particle swarm optimization (PSO), is implemented. The results show that using both the Kalina cycle and desalination unit can improve the energy and exergy efficiency of the plant by 11.4 and 6.02. However, the case where only the desalination unit was employed had the highest monetary and ecological performance by 87.25 and 88.11%, which were increased to 90.3 and 97.8% after the optimization, showing a significant improvement compared to the base cycle.