Performance analysis of nanofluid-based spectral splitting PV/T system in combined heating and power application

Highlights: • A calculation model for NSS-PV/T system in combined heating and power application is developed. • The optical window of NSS-PV/T system depends on the heat-to-electricity ratio of system. • A system with high heat-to-electricity ratio is more suitable to adopt the NSS-PV/T technique. - Abstract: Nanofluid-based spectral splitting photovoltaic/thermal (NSS-PV/T) system has attracted increasing attentions for its flexible adjustment of energy distribution between photovoltaic and photothermal units and the breakthrough on the temperature of collected thermal energy. In this work, a calculation model is developed to analyze the performance of the NSS-PV/T system in combined heating and power application which were reported by few literatures. Besides the optical window of nanofluid, the impacts of three main parameters including the concentration ratio, the outlet temperature of cell cooling channel and the outlet temperature of heat exchanger on the heat-to-electricity ratio, the thermal efficiency and the overall efficiency of system are analyzed in depth. The results indicate the regulation mean of optical window is the most effective way to adjust the heat-to-electricity ratio and improve the efficiency of system. Moreover, appropriate promoting the outlet temperature of cell cooling channel is recommended in practical application for its benefits on widening the adjustable range of heat-to-electricity ratio and improving the efficiency of system. In addition, those applications with a low demanding temperature and high heat-to-electricity ratio are more suitable to adopt the NSS-PV/T system with cell waste heat collection for its outstanding performance.