Collaborative Optimization Between Passive And Active Heating For Buildings In Cold Area

Due to cold winter and cool summer in alpine region,building heating energy consumption is an important part for buildings located in the alpine region,and reducing the heating energy consumption is one of the main energy-saving methods for buildings.In the process of building heating,passive heating and active heating are always working together.To optimize the building heating performance,it is necessary to clear the relationship between the passive building design and the active heating system.However,it is impossible to obtain the specific quantitative optimization relationship between the passive building heating and active heating systems based on existing research methods.Therefore,in order to improve the performance of building heating,it is necessary to study the collaborative relationship between the passive heating measures and active heating systems.In this paper,theoretical analysis,numerical simulation,experimental test and multiobjective optimization are adopted to study the optimization problem of building heating.A collaborative optimization method is proposed to determine the optimal passive heating measures and active heating systems.The railway passenger in cold area is selected as the research object,two modes including the combined system of passive building heating and air source heat pump heating,the combined system of passive building heating,solar air heat system and air source heat pump heating are analyzed to find the collaborative relationship among the passive building,solar air heating system and the air source heat pump system.The optimization combinations of design parameters from passive building design and air source heat pump are also studied.The details are as follows:First of all,based on the technical characteristics and functions of passive building heating and active heating systems,the multi-objective optimization theory is employed to establish the mathematical model of the collaborative optimization between the passive building heating and active heating systems.Meanwhile,a "grading type" method is proposed to solve the mathematical model.Some cases are conducted to validate the rationality and the accuracy of the cooperative optimization method.Secondly,according to the multi-objective optimization theory,the multi-objective optimization model and solving method for the passive building heating are established.The model includes economic and energy saving optimization goal,passive design variables and constraints,etc.Based on the multi-objective optimization model,various factors affecting the building accumulation thermal load and the building construction cost of passive building heating are analyzed.The economic and energetic collaborative relationships are achieved under different constraints,and the optimum combinations including different passive design parameters are also obtained.In the case study of railway passenger stations,if the passive construction cost is unchanged,the optimized combination can reduce the building accumulation thermal load by 74.8% compared with the original design scheme.If the building accumulates thermal load is constant,the optimal combination can reduce the passive construction cost by 7.6%.Then,when the railway passenger station uses passive building and air source heat pump for heating,according to the proposed collaborative optimization method and the optimization results for passive building heating,the cooperative relation between passive building heating and air source heat pump system is established.From the perspective of the whole building heating,the relationship between the total energy consumption and the total cost within the whole life cycle is analyzed,and the design parameters from passive building and air source heat pump is adjusted to obtain the optimized combinations.After case analysis,it is found that during the whole life cycle of the railway passenger station,the total cost in the heating economy point can reduce 30.5% compared with the initial design scheme,and the total energy consumption in the heating economy point can reduce 85.6%.Finally,when the railway passenger station uses passive building,solar air heating system and air source heat pump for heating,according to the proposed collaborative optimization method and the optimization results for passive building heating,the cooperative relation between passive building heating,solar air heating system and air source heat pump system is established.From the perspective of the whole building heating,the relationship between the total energy consumption and the total cost within the whole life cycle is analyzed.Compared with collaborative optimized results from the mode including the passive building heating and the air source heat pump,it is found that the use of solar air heating system can significantly reduce the total heating energy consumption of the building,but also can increase the building heating total cost.Furthermore,with the continuous input of passive construction cost,the solar air heating system can increase the heating energy saving rate from 8.4 % to 56.5 %,and reduce the heating cost increasing rate from 10.9 % to 2.0 %.