Examining the receiver heat loss, parametric optimization and exergy analysis of a solar power tower (SPT) system

Abstract

Thanks to the studies on the material properties of the future solar tower systems and together with the developments in the material science, it has been observed that higher operating temperatures can be possible for SPT and steam turbine systems. Therefore, in this study, by ignoring the thermal resistances of materials, a steam turbine cycle assisting SPT system was simulated for a tower outlet temperature reaching up to 1800 degrees C depending on the solar radiation rate, the receiver surface temperature and the steam temperature at the tower outlet. When all data obtained from the system was analyzed by considering the future development, it was obviously seen that no matter how the thermal resistance of the materials used in SPT systems advanced, system performance could only be improved up to a certain high temperature. Because the only factor influencing the efficiency of the system is not the tower outlet temperature on its own. There are many other factors like thermal heat losses, optical heat losses, solar radiation rate, environmental and climatic conditions. Hence, the maximum net power production of the SPT plant was calculated as 10,306 kW at 960 degrees C in December while it was found as 49,641 kW at 1500 degrees C in July. Throughout the months, above the maximum temperatures where maximum performance obtained from the SPT, it was observed that the system performance worsened due to increasing heat losses, receiver surface temperature limitation and limited solar radiation rate.