Multi-objective optimization and exergoeconomic analysis of a continuous solar-driven system with PCM for power, cooling and freshwater production

In this article, three different modes of a novel integrated system would be evaluated by the application of high temperature Thermal Energy Storage (TES) to produce electricity, cooling, and freshwater. Freshwater is produced using the reverse osmosis (RO) desalination unit while Absorption Refrigeration Cycle (ARC) provides cooling. In this system, a high temperature Phase Change Material (PCM) is utilized to make the system working continuously even at nights. The output heat of gas turbine (GT) is also recovered utilizing the Organic Rankine Cycle (ORC). According to exergoeconomic analysis, the efficiencies, exergy destructions and product cost rates are computed. The multi-objective optimization has also been performed considering six different ORC working fluids and the changes in the direct normal irradiation of a city in Iran. In the trigeneration condition, the optimum values of the GT’s compressor pressure ratio and ORC’s turbine inlet pressure were obtained 9.06 and 3300 kPa, respectively. The exergy efficiency of the suggested system at the optimal condition is computed to be 14.40%, while that of energy is 40.52% with the total product cost rate of 30.524 $/GJ. The produced cooling capacity of the absorption system is also 1.62 MW whereas the output amount of freshwater and electricity for the users are about 5209.5 m3/day and 2.42 MW, respectively. The Levelized Cost of Electricity (LCoE) is also calculated to be 0.2341 $/kWh, which shows promising economic performance.