| Photovoltaic/thermal comprehensive utilization technology(PV/T)can provide electric and thermal energy,which is an efficient and clean utilization of solar energy and can obtain economic benefits and good environmental effects.It has been widely applied and developed in various fields all over the world.The performance of PV/T module directly affects the photoelectric conversion efficiency,photothermal conversion efficiency and solar energy comprehensive utilization efficiency.The traditional PV/T collector is mostly made of metal materials with good thermal conductivity,such as copper and aluminum.In this paper,a new type of double glass bificial PV/T component with glass channel is designed and manufactured,that is,the collector adopts tempered glass as the material,the structure of the collector is a flat box with the upper end open,and the bottom of the collector is made into a reflector surface.Compared with the traditional metal flat box-type structure collector,the working medium in the glass channel of this new structure is directly in contact with the PV cell back plate,which reduces the heat transfer resistance and enhances the cooling effect of the working medium on PV panels.In addition,the bottom of the collector made into a mirror can reflect the light transmitted between the gaps of the PV panel back to the back of the bifacial PV panel for further power generation,increasing the utilization rate of light and improving the photoelectric conversion efficiency.In order to better study the performance of the new glass channel collector with double-glass bifacial PV/T component,a set of experimental platform for biaxial tracking was built.On the basis of existing studies,a CPC-PV/T cogeneration system with low-concentrated was formed with CPC concentrator.The first law of thermodynamics is used to analyze the energy balance equation of the system.The performance of the PV/T component of this new type of glass channel collector is verified by a series of comparison experiments with the traditional aluminum channel PV/T and experiments with different operating modes.The main results are as follows:1)Under the condition of non-concentrating and without cooling,the average electrical efficiency of the PV/T component with glass channel was 13.93%,and the highest electrical efficiency was 15.61%during the experiment;the average electrical efficiency of PV/T component with aluminum channel was 11.39%,and the highest electrical efficiency was 13.04%.The electrical efficiency of the PV/T component with glass channel was significantly higher than that with aluminum channel,and the average electrical efficiency was 2.55%higher.It is proved that the heat flow of the PV/T component with glass runner is better than that with aluminum channel.The advantages of the designed structural glass channel collector in heat transfer are proved.2)Under the condition of non-concentrating and cooling water flow rate is 80L/h,the average electrical efficiency of the PV/T component with glass channel is 17.13%,and that in the aluminum flow channel is 14%.It can be seen that the electrical efficiency of the glass channel is 3.13%higher than that of the aluminum channel.The average thermal efficiency of the glass channel PV/T component is 47.25%,and that of the aluminum channel PV/T component is 44.41%.On the whole,the thermal efficiency of the glass channel PV/T component is higher than that of the aluminum runner PV/T component,which further indicates that the cooling effect of the glass channel collector is better than that of the aluminum channel collector.The average total efficiency of the glass channel PV/T component was 64.38%and that of the aluminum channel PV/T component was 58.41%during the experiment.3)Under the condition of concentrating and cooling water flow rate is 80L/h,the average electrical efficiency of the PV/T component with glass channel is 13.1%,the average thermal efficiency is 51.22%and the average total efficiency is 64.32%.The average electrical efficiency,the average thermal efficiency and the average total efficiency of PV/T components with aluminum channel were 10.46%,41.33%and 51.79%respectively.The glass channel PV/T module not only performs well in thermal performance,but also performs much better in electrical performance than the aluminum channel PV/T module under concentrating condition.4)In the cooling water channel series and parallel experiments,the average electrical efficiency,average thermal efficiency and average total efficiency of the LCPV/T components of the water channel series system were 13%,48.13%and 61.13%respectively.The average electrical efficiency,thermal efficiency and total efficiency of LCPV/T components of the water channel parallel system were 14.9%,58.69%and 73.59%respectively.In comparison,The electric efficiency and thermal efficiency of the cooling water channel running in parallel are obviously higher than that of the cooling water channel running in series. 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