Exergy analysis of a solar organic Rankine cycle with square prismatic cavity receiver

In this study, a solar organic Rankine cycle (ORC) was empirically modelled. A solar dish collector with a tubular cavity receiver was used as the ORC heat source. The effects of the solar irradiation, the depths of the cavity receiver, and the diameter of the inner cavity tube on the exergetic performance of the tubular cavity receiver were investigated. The exergy parameters such as the receiver exergy rate, the thermal exergy efficiency, the receiver exergy factor, and the electrical exergy efficiency were analysed. The results revealed that the optimum structure of the tubular cavity receiver for achieving the highest receiver exergy rate, thermal exergy efficiency, receiver exergy factor, and electrical exergy efficiency, was the cubical cavity (i.e., cavity depth equal to the side length of the cavity) with the smallest tube diameter.