Thermodynamic investigation of a solar-driven organic Rankine cycle with partial evaporation

The partial evaporation organic Rankine cycle (PE-ORC) is an emerging technology for the efficient exploitation of low-temperature heat sources. The purpose of the present study is the energy and thermodynamic analysis of a solar-fed PE-ORC with a solar field of evacuated flat plate collectors coupled to a sensible storage tank. The studied PE-ORC operates with the environmentally friendly working fluid R1233zd(E) with variable evaporation percentage in the expander inlet. The thermodynamic investigation is done with a validated model in Engineering Equation Solver, and the transient analysis is performed with the TRNSYS tool by coupling it with the thermodynamic model. According to the dynamic analysis, the annual electrical yield is found at 6243 kWh, while the maximum obtained value is found at 3.81 kW. Moreover, the annual mean solar field efficiency was calculated at 45.0%, the annual mean thermodynamic cycle efficiency at 8.71% and the annual mean system efficiency at 3.68%.