Study On Multi-source Complementary Heating System In Buildings Of High-speed Service Area In Severe Cold Region

Since China put forward the international commitment of "achieving carbon peak by 2030 and carbon neutrality by 2060",it has become a social hot spot to achieve energy conservation,emission reduction,low-carbon production and life.In the building field,energy consumption of HVAC system is huge,especially in our country’s severe cold area,the high energy consumption and high pollution brought by winter heating has become the social focus.How to achieve clean and low energy heating under the premise of satisfying people’s thermal comfort has become a top priority.The buildings in the expressway service area are far away from the urban central heating pipe network.At present,most of them use earth furnace or electric boiler for heating,which is high pollution and energy consumption.Based on this background,this paper designed a multienergy complementary clean heating system of solar energy and soil source heat pump combined regenerative thermoelectric boiler for highway service area buildings in cold regions according to the outdoor temperature changes in different stages of heating period.A high speed service area building with a heating area of 7000m2 was selected.The dynamic heat load of the building during the heating period was simulated and analyzed by DeST-c energy consumption simulation and analysis software.The heat source equipment was selected according to the maximum design heat load of the building,and the proportion of the building load borne by the soil source heat pump unit was calculated.Five different heating schemes of 80%,75%,70%,65%and 60%were designed respectively to determine the optimal heat source load ratio scheme of the system,and the operation of the system in different stages of the heating period was studied.Using TRNSYS transient simulation software as a platform,a comprehensive comparative analysis was conducted on the annual heating capacity,annual power consumption of soil source heat pump,heat collection of solar heat collection tank,heat storage tank,water supply temperature stability,soil average temperature and recovery ability,and system economy of five different heating schemes.The results show that:When the proportion of heat load borne by the soil source heat pump is 65%,it is determined to be the best scheme.By studying the operation characteristics of the optimal ratio scheme in different heating stages,it is found that the distance between the buried pipes is 6.0m and the depth is 100m.In this case,the COP level of the heat pump unit after 10 years of operation is the best,and the heat load demand of the building heating season can be met.The accuracy of the simulation results is verified by comparing the water supply temperature data of the demonstration building in the early stage of operation.Finally,the comprehensive evaluation and analysis of the multi-energy complementary heating system are carried out from the aspects of energy saving and environmental benefit.The results show that the optimal heating scheme consumes 511707.49kW·h,which reduces energy consumption by 55.56%compared with traditional electric boiler heating.At the same time,combined with the operation regulation and operation control modes at different stages of heating,CO2,SO2 and dust emissions per unit building area were reduced by 10.593kg,0.08kg and 0.04kg,respectively.To sum up,by scientifically determining the multi-energy complementary joint heating scheme and the system operation regulation strategy,the winter heating demand of buildings in high-speed service areas in cold regions can be fully met while energy saving and emission reduction can be achieved,and low-carbon and clean heating can be finally realized.