Energy, exergy, and economic analysis of a solar photovoltaic and photothermal hybrid energy supply system for residential buildings

Abstract

In this study, a dynamic simulation model is developed based on the mathematical model of a solar photovoltaic and photothermal hybrid energy supply system (PV-PTHS) employing the TRNSYS simulation software. The corresponding operational control strategy for the PV-PTHS is proposed. The impact of different PV and PT areas on the performance and the energy and exergy flows of the PV-PTHS throughout the year are analyzed using simulations. In addition, the dynamic performance of the PV-PTHS on typical days is reported during the heating period, transition period, and cooling period. Also, the monthly exergy performance of the system is comprehensively analyzed. Finally, the cost-effectiveness and energy savings of the PV-PTHS are reported and compared against the single PT and single PV systems. The results show that the energy loss of the PV cells is the highest, followed by the solar collector. However, the exergy efficiency of the collector is lower than that of the PV cell in the PV-PTHS, and the low exergy efficiency of the collector results in a lower exergy efficiency of the PT subsystem (PTS). Considering similar initial investments, the PV power supply ratio of the PV-PTHS is the highest in areas with a large heating load, such as Nagqu and Yinchuan. The heat supply ratio and the cost-effectiveness of the signal PT system are the best. Overall, the proposed PV-PTHS yields the highest primary energy saving ratio (PESR) and the best cost-effectiveness for areas with a small heating load, such as Wuhan and Fuzhou.