The Establishment Of A Life-Cycle Carbon Emission Factor Database For Buildings And Research

With the accelerated process of industrialization, greenhouse gas, especially carbon dioxide emissions leading to global climate change is increasingly affecting human survival and development. The carbon dioxide emissions from construction industry accounts for 36% of the global total emissions each year directly or indirectly. Therefore, it is significant to measure the amount of tcarbon emissions of buildings and then develop appropriate ways to control and reduce the resource and energy consumption associated with construction activities.In addition to input-output method, related-industries table method and other macro approach to calculate building carbon emissions, factor-based method is mainly used. The method based on reasonable calculation formulas for life-cycle phase of a building is easy to operate and wide applied, but the accuracy of the results depends on the complete carbon emission factor data.Currently, the popular environmental impact database and calculation tools for a building domestic and abroad include:Standard Reference Data in America (SRD), Inventory of Carbon and Energy in the UK (ICE), Athena Life Cycle Calculation Software in Canada (Athena), the Economic Input-Output Life Cycle Assessment in America (EIO-LCA), US life-cycle Inventory Database in America (NREL) and China Life Cycle Database (CLCD) and so on. However, the shortcomings of above database are obvious: First, lack of relevance. They considered the building carbon emissions an indicator of environmental impact, and the proportion is small; secondly, time-poor. The data in the database mostly age-old; furthermore, lack of regional difference. Most of the relevant statistical data are from abroad which do not meet the current situation of China’s construction industry; finally, lack of integrity. They only took some certain phases or certain types of building materials into consideration instead of the life-cycle.In summary, this paper intends to establish a life cycle carbon emission factor database query and computing system for buildings with the characters of China localization, completed and newer data, automated calculation. After analysis the three aspects of stages division, measurement methods and metrics, etc., this paper determined the research methods and technology roadmap as follows:First, define the concept of carbon emission factors, the system and process boundaries of measurement. According to the direct and indirect effects factors of carbon emission in each stage of the life cycle, summarize four categories of life-cycle carbon emission factors:energy, materials production, transportation, machinery and equipment. It came up with a calculation method of life-cycle carbon emissions for buildings. Collected and integrated various types of carbon emission factor data by scholars, national standards, yearbooks and other data.Then, this article used SQLite 3.0 as building carbon emission factor database platform, Qt 4.7 as a graphical user interface, Windows as the operating system platform to build "The Life-Cycle Carbon Emission Factor Database for Buildings". The main function modules of the system include:data import and export, the carbon emission factor query and editing, building life-cycle carbon emissions calculation. At the same time, the system also equipped registration and login function which guaranteed the personalization and security; reserved function interface for secondary development; Chinese word segmentation system to improve data recognition and search capabilities.Furthermore, in order to verify "The Life-Cycle Carbon Emission Factor Database for Buildings" on practical engineering, it calculated the life-cycle carbon emission, as well as that in each stage, of a residential building in Nanjing. The results showed the amount and proportion of carbon emissions, and analyzed the factors and reasons, proposed appropriate measures to reduce emissions.Finally, this paper demonstrated the shortcomings of research, newer and more accurate carbon emission factors need to supply and update at any time; prospected future research, namely establish and improve the localization of carbon emission Factor Database for buildings in China.