Abstract: Abstact:This paper studies the performance of a dual-channel PV/T system with water as working fluid. The optical properties of waterwere characterized,and we built a laboratory experiment setup to conduct experimental research on the performance of the dual-channelPV/T system under laboratory conditions. Effects of different flow rates and with or without a phase change material layer on theperformance of the system were investigated,including the impact on the working temperature of sdar cells and the electric and thermalefficiencies of the system. The experiment results show that the dual-channel PV/T system can effectively reduce working temperature ofsdar cells. When the flow rate of working fluid increases from 100 m L/min to 300 m L/min,the average temperature of sdar cells of thedual-channel PV/T system decreases by 1.77 ℃,and the electric and thermal efficiencies increase by 0.09% and 4.11%,respectively.Compared with the electric performance,changes in flow rate have a greater impact on the thermal performance of the system. The dualchannel PV/T system with phase change materials further reduces the operating temperature of the solar sdar cells. The electric andthermal efficiencies of the system are improved,and the system can reach a higher overall conversion efficiency.