Study On Performance Of Multi-energy Complementary Heating System Based On PV/T

On the one hand,the multi-energy complementary heating technology can improve the instability of single energy heating,and on the other hand,it can also improve the operating efficiency of the system.Among them,the solar coupled heat pump system,which is a strong representative,is widely used in heating for residents in northern China,and it is of great significance to improve the haze environment and energy saving and emission reduction in northern China.In order to further improve the application level of clean energy and obtain an efficient and stable multi-power complementary heating system,a PV/ T-based complementary heating system was proposed in this paper,combining the characteristics of photovoltaic/Thermal(PV/T)and heat pump.The system is PV/T coupled water source heat pump and air source heat pump(referred to as the system).The PV/T collector applies the waste heat recovery of photovoltaic panels to the evaporation end of the water source heat pump,and the air source heat pump serves as the auxiliary heat source for heating.Taking an office building in Jinan City as an example,the system design and selection were carried out,and the system operation experiment platform and operation simulation model were built.trnsys was used to optimize the connection mode,operation scheme and design selection of the system,which provided a reference for the feasibility study of the system in the cold northern region.Recorded for three typical day in the middle of the heating season experiment data,sorting data for system operation characteristic,using the trnsys simulation software of indoor temperature,load side temperature,heat storage water tank temperature,photoelectric conversion efficiency,photovoltaic battery power to carry on the simulation,the simulation results compared with the experimental results validate,found that the experimental and simulation data change trend is consistent,And the error is within a reasonable range,so the model is used to optimize the system.The simulation results show that the temperature of the heat storage tank is high at the beginning and end of the heating season,so it is proposed to set the direct supply mode during this period.The results show that 185.57 k Wh of power can be saved in a heating season by setting the direct supply mode.Based on the direct supply mode,three operation schemes were proposed according to the variation characteristics of building load and meteorological parameters,and simulation models were established to simulate them respectively.The changes of the system’s power generation,power consumption,photoelectric and photothermal conversion efficiency,heat pump COP and other parameters under the three operation schemes were analyzed.System performance evaluation indexes of energy efficiency and exergic efficiency were proposed.The calculation results showed that exergic efficiency and exergic efficiency of Plan 2 were 16.19% and 7.72,respectively,indicating the best operation effect.Taking the maximum amount of solar radiation received by the collector as the optimal objective function,the best inclination and azimuth Angle of the collector were obtained.Taking the minimum annual cost as the optimization objective function,the optimal volume of the heat storage tank and the optimal area of the collector are obtained.The economic and ecological benefits of the system under the control of scheme 2 are evaluated,and the total cost of system operation and maintenance management is 841 yuan,and the annual cost is 594 yuan.Compared with several common heating methods,such as gas wall-hung boiler,ordinary electric boiler,coal-fired boiler,air source heat pump,etc.,the pollutant emission value of this system is zero,and the ecological benefit is more obvious.The research results show that the system proposed in this paper has strong technical adaptability,economic and environmental protection,and the heating effect of the optimized system is improved significantly.This paper provides a reference for the heating research of PV/T coupled heat pump system in the cold northern region,and makes a contribution to reducing the pressure of energy consumption and environmental pressure in China.