A combined CPV/T and ORC solar power generation system integrated with geothermal cooling and electrolyser/fuel cell storage unit

This work investigates the behavior of a solar power generation system that consists of a concentrated photovoltaic/thermal (CPV/T) system that utilizes an Organic Rankine Cycle (ORC) integrated with a geothermal condenser and an energy storage unit. The storage unit consists of an electrolyser and Proton Exchange Membrane (PEM) fuel cells. The electrolyser that is powered by both the PV cells and the ORC produces Hydrogen and Oxygen from impure water. The PEM fuel cells are used to restore the produced chemical energy and convert it to electrical form. A general steady state mathematical model is proposed and simulated; however, the data that are used in investigating the model is for Jordan. The present results are validated via comparisons with those in the literature. A parametric analysis is conducted to investigate the effect of some key parameters on the system performance. Examples of these parameters are the inlet turbine temperature, the average solar incident radiation, the ambient temperature and the parameters of the storage system. The simulation shows that an increase in the inlet turbine temperature increases the overall efficiency when the temperature is lower than 61 °C and acts the opposite otherwise. Other parameters like the average solar incident radiation and the ambient temperature also have significant effects on the performance of the proposed power system. It is also found that the overall electrical efficiency of the proposed combined power system is improved by 15.72%-17.78% due to the usage of ORC. While using the storage system, this system can achieve 18.21%-21.95% efficiency when it is operated in November considering the worst case scenario in the studied location. On the other hand, the CPV cannot work efficiently without the cooling system. Considering the best performance which occurs in November for the studied location, the PV cell's efficiency reaches 3.88% without cooling in comparison to 18.92%, while using the cooling system and 21.96% with using the ORC as a waste recovery system.