Design Method And Experimental Study On Heat-pipe Concentration Photovoltaic-thermal Module

As solar energy is one of the most important renewable energy,solar energy application technology has attracted tremendous attention in the last decades.Among these technologies,solar photovoltaic technology and solar thermal technology are two important ways of solar energy utilization.But the two technologies are usually used independently,with a single form of energy collection and a low conversion efficiency.Hence,in order to improve the efficiency of solar energy conversion and to meet the demands of ordinary household electricity and hot water,the development of solar photovoltaic-thermal technology has become one of the important research directions of solar energy utilization.This research proposes a heat pipe concentration Photovoltaic-thermal(HP-HCPV/T)module based on high concentration photovoltaic(HCPV)technology.In the HP-HCPV/T module,a concentrator with point-focus Fresnel lens and a secondary optical prism structure are used to concentrate and uniform the solar energy.Besides,three junction(GaInP/GaAs/Ge)CPV cells are used for electricity generation.At the same time,as heat pipe has a high thermal conductivity,a kind of heat pipe water-cooling technology is used to collect the waste heat and cool the CPV cell,which achieves efficient thermal utilization.To summarize,the main contents and results of this study are given as follows:Firstly,a kind of HP-HCPV/T module structure is designed,and its concentration photovoltaic block and heat pipe water-cooling block are analyzed.What's more,based on the heat transfer limit principle of heat pipe,the paper presents a design and selection method of heat pipe for HP-HCPV/T module.Secondly,the complete theoretical analysis model of the HP-HCPV/T module is established,and the model solving program based on the EES engineering equation solver is written.The performances of the module in standard test conditions(irradiation intensity 1000W/m~2,ambient temperature 25?)are simulated by the model,and results show that the electrical efficiency is about 27.7%,the average thermal efficiency is about 48.7%and the overall efficiency is about 76.4%,which means the utilization efficiency of solar energy is greatly improved.Besides,the performance of the HP-HCPV/T module under different working conditions is simulated,which provides the theoretical basis for the optimal design of the module.Finally,in order to test the real performance of the module,an outdoor experimental setup is built.On the basis of experimental data,the electrical and thermal performance of the module is evaluated and compared with the theoretical model.The results show that the theoretical simulation is consistent with the experimental results.The theoretical model of HP-HCPV/T module can effectively predict the performance of module,which lays a theoretical foundation of the practical application and popularization of HP-HCPV/T moudle.