Proposal and analysis of a concentrating photovoltaic-driven system for combined production of electricity, hydrogen, and low-temperature refrigeration

Abstract

A trigeneration system that uses concentrating photovoltaic (CPV) waste heat for low-temperature refrigeration and surplus electricity to power an electrolyzer for hydrogen synthesis is presented in this research to address the energy demands of a multi-unit building. Energy and exergy assessments evaluate system performance under various situations. The ANSYS-FLUENT and Engineering Equation Solver are used. To evaluate its energetic and exergetic performance, the system is studied at different direct normal irradiation (DNI), photovoltaic areas, and absorption chiller driving temperatures. At a constant DNI, increasing the coil diameter from 400 to 600 mm may raise channel water temperature by 3–5%. Ejector-absorption cycle driving temperature enhancement from 65 to 95 °C increased refrigeration capacity from 22 to 34 kW, hydrogen production from 0.76 to 2.8 kg/h, and power generation from 5.9 kW to 4.1 kW. By increasing the photovoltaics area from 78 to 126 m2 and using an absorption chiller and electrolyzer, system energy and exergy efficiencies increase by 23.47% and 8.02%, respectively, while CPV exergy efficiency decreases by 18.06%. The CPV destroys the most exergy in the system, whereas the electrolyzer destroys the least. Combining photovoltaics and the refrigeration machine with an electrolyzer is a novel approach to harnessing sunshine energy.