In order to study the thermal efficiency

electrical efficiency and primary-energy saving efficiency of the hybrid photovoltaic/thermal(PV/T)solar system and their affecting factors

this paper built up an experimental system and analyzed the effects of cooling fluid

water flow speed and cover ratio of PV cells on the PV/T system performance

on the basis of comparison of such parameters as all day solar energy radiation

environmental temperature and entrance water temperature between the PV/T system and the PV system.The results show that the average electrical efficiency of this PV/T system was 0.91% higher than that of the PV system.With low water mass flow rate

both the thermal efficiency and electrical efficiency of the PV/T system were low

but the outlet temperature and exergy efficiency were high.Additionally

there was a significant negative correlation between the thermal efficiency and packing factor

but the electrical efficiency had a positive correlation with the packing factor.