The Economic Analysis Of Building Thermal Performance Optimization Design Process Based On Bim Collaborative Design

The traditional architectural design products not only take a tremendous amount of non-renewable energy, but also require a lot of energy consumption in the process of the operation, which caused serious damage and pollution to the ecological environment. Building thermal performance optimization and the use of renewable energy can maximize the reduction of energy consumption and the improvement of the overall performance, and meet the people’s requirements about the indoor comfort. Thermal performance optimization is often accompanied by the change of the investment and the energy running costs。It is very important to analyze the economy of building thermal optimization objectively and comprehensively especially in the energy shortage today. The article establishes the BIM collaborative design platform based on full life-cycle costs controlling, uses the full life-cycle annual costs and the dynamic additional investment payback period to analyzes the economy of the building thermal performance optimization program completed on the BIM collaborative design platform. Through literature review, theoretical analysis, and engineering case studies, the article’s analysis focuses on the following questions:Firstly, for the lack of a comprehensive and objective economic analysis on the problem of thermal design optimization in the early design process and too much emphasis on the initial investment, the article dwells on the relationship among the full life-cycle costs, the initial investment and the running costs, and studies the economic analysis method of the building thermal performance optimization solutions and sets the economic analysis method in which the full life-cycle annual costs and the dynamic additional investment payback period as the evaluation indicators.Secondly, the BIM collaborative design platform is established based on full life-cycle costs, and the building thermal optimization design platform is organized which can provide a platform for architects, HVAC engineers, cost engineers and other professionals to work together. Architects complete the program’s building information modeling by the BIM collaborative design platform. HVAC engineers and cost engineers respectively analyze the performance and the costs of the building information modeling completed by the architects, and they give the feedback of the related analysis results and the suggestions to the architects through the collaborative design platform to help the architects complete the optimization program.Thirdly, the analysis of the decision-making process of building thermal performance optimization based on full life-cycle costs is completed with the case of a five-story residential in Hohhot. The optimized solution of130mm thick polystyrene board and plastic coated low-E windows can be determined from the lowest full life-cycle costs point of view, which can save energy by28.72%based on the standard of65%energy-saying. Its additional investment is58.01yuan/m2, annual energy-saving benefits is14.34yuan/m2, and annual carbon dioxide emissions reduced by20.66kg/m2. The additional investment payback period is less than5years even taking into account the time value of money.Finally, this paper completes two practical engineering application cases of economic analysis and the decision-making method on the BIM collaborative design platform based on the full life-cycle cost controlling. Through case studies, we can discover the design programs meet the current standard of65%energy-saving (Beijing residential building energy efficiency standard is75%) which energy efficiency can be achieved re-saving10%-30%based on the original design criteria and additional initial investment can be recovered through energy efficiency gains in a very short time, if we optimize the building thermal performance and use the full life cycle costs and additional investment payback period analysis tools to determine optimization solution.