Design And Operation Characteristics Of Solar Energy Utilization System In Alpine Region

Energy crisis and environmental problems are becoming increasingly prominent,which makes the research and promotion of clean and efficient new energy more urgent.In recent years,worldwide policy support and technological progress have promoted the application of renewable energy such as solar energy,biomass energy,geothermal energy and wind energy.Among them,solar energy is an inexhaustible and clean energy,which will not pollute the atmospheric environment in the process of solar energy utilization.Solar energy has great potential in alleviating the increasingly severe energy crisis and solving environmental problems.Firstly,a solar-air source heat pump coupling system in the existing ultra-low energy consumption residential buildings in the alpine region(Qinghai Province)is tested in most of aspects.The corresponding system model is established on the simulation platform TRNSYS.The results are compared,analyzed and discussed.The evaluation indexes of the system are calculated,which provides a reference for the subsequent novel system.Secondly,A new type of building heating system is proposed,in which the photovoltaic/thermal(PV/T)subsystem and trough collector are connected in series as the main heat source and electric heating as the auxiliary heating mode.The performance of the novel system is compared with the above case system from three aspects of solar energy utilization,renewable energy utilization and economy.Through the comparison,it is found that the heat collection per unit area and the heat collection efficiency of the novel system are increased by 31% and 30%,respectively.However,the utilization of renewable energy is decreased by 44.5%,and the economic difference between the two systems is not obvious.Finally,based on the above research,the system form is optimized and a novel solar thermoelectric coupling system is proposed,which combines PV/T subsystem with Organic Rankine Cycle(ORC)driven by trough collector.The mathematical model of the coupling system is established,and the influence of the area ratio of two kinds of collectors(photovoltaic panels and trough collectors)on the power generation performance of the system is discussed.The performance of the coupling system and two independent systems(PV/T and solar ORC system)is compared and analyzed.The results show that the optimal area ratio of the collectors is 8:2.Compared with the independent system,the coupling system has higher reliability.The solar energy utilization efficiency is increased by 40%,and the available output energy per unit area is increased by 13%.Moreover,the system form of coupling makes the power generation efficiency of photovoltaic panels increase by 1.5%-3.5%.Through the comparative study of the above three kinds of solar energy utilization systems,the operating characteristics of different renewable energy systems in alpine regions is discussed.The design idea of novel solar energy utilization system is put forward,which provides a reference for the design and optimization of related energy systems and provides a new idea to improve the energy structure and promote the development of renewable energy.