Comprehensive thermodynamic and exergoeconomic analyses and multi-objective optimization of a compressed air energy storage hybridized with a parabolic trough solar collectors

Abstract

This paper designs a novel power plant consisting of a medium-temperature solar field based on parabolic trough solar collectors, an organic Rankine cycle, and a compressed air energy storage unit. The solar field supplies the energy required by the organic Rankine cycle at the charging period, providing the power for the compressors and high-temperature energy storage. Also, for the performance improvement of the system, zeotropic mixtures are employed as the working fluids in the Rankine cycle. The system was assessed from energy, exergy, and exergoeconomic viewpoints. A comprehensive parametric study was performed to examine the effects of some key parameters on the performance of the devised system. And, the MOPSO optimization algorithm is selected to optimize the calculations, wherein the TOPSIS decision-making method identifies the optimal solutions. According to the results, Isopentane/R142b mixture was selected as the efficient zeotropic working fluid of the Rankine cycle. Hence, the optimum energy efficiency and exergy efficiency were computed to be 5.08% and 5.04%, respectively. Besides, the optimum round trip efficiency and exergetic round trip efficiency were obtained by 57.06% and 66.20%, respectively. Moreover, considering electricity cost of 0.36 $.GJ−1, the lowest payback period of 4.39 years, and the highest profitability were obtained.