Experimental Study Of Heat Pipe Solar Photovoltaic/Thermal Systems Utilization

Affected by the fossil energy crisis and environmental pollution problems,the development and use of new energy has become a research hotspot for scholars.Among them,the use and promotion of solar energy and other clean energy are effective ways to alleviate resource shortages and solve environmental problems.In recent years,the comprehensive utilization technology of solar photovoltaic/thermal has been rapidly developed.The comprehensive utilization technology of solar photovoltaic/thermal is a combination of photovoltaic power generation technology and heat collection technology.It can not only obtain electric energy,but also can recycle the heat stored in photovoltaic cells,and has the dual functions of photovoltaic power generation and heat collection.This technology can not only improve the utilization efficiency of solar energy,but also meet the needs of people's life and production.Considering the influence of pump work and environmental factors,this paper proposes an evaluation method for active solar photovoltaic/thermal systems,a parameter that can characterize the energy return of active solar PV/T systems—the actual energy yield efficiency.The actual energy yield efficiency as an evaluation method under a specific condition is used to define the overall performance of an active solar PV system.In this paper,a flat micro heat pipe collector is designed and assembled and tested under different influence factors.The research shows that the installation inclination can not only affect the heat transport capacity of the heat pipe,but also affect the solar radiation reception effect.Considering both considerations,the optimum installation inclination of the flat micro heat pipe collector can be determined;under the condition of the solar radiation wavelength range,the coating The heat transfer efficiency of the collector with black chromium coating was relatively increased by 11%.Under heat conduction conditions,the black chromium coating had little effect on the heat transfer efficiency of the collector.Based on the characteristics of high heat transfer capacity of flat micro heat pipes,this paper combines flat micro heat pipes with pure photovoltaic components to design a new type of heat pipe solar photovoltaic/thermal system.Heat pipe solar PV/T system and PV system were tested under the same working conditions,and the influence rule of PV/T system's photoelectric efficiency,thermal efficiency and actual energy yield rate were analyzed.The results show that the maximum practical energy yield rate can be obtained when the working volume of the PV/T system is 320L/h.The increase of the mass flow increases the electrical efficiency of the PV/T system,but has no obvious effect on the system photoelectric efficiency.Under clear weather conditions,the maximum actual energy yield rate during solar energy PV/T system operation can reach 40.30% throughout the day,and the average actual energy yield rate over the day is 32.16%,which is 19.12% higher than that of pure photovoltaic power generation system.