Hybrid input-output analysis for life-cycle energy consumption and carbon emissions of China's building sector

With respect to global climate change, energy consumption and carbon emissions of the building sector has become an increasingly crucial issue in the sustainable development of China. While process-based analyses have been performed in previous research, in the present study, we propose a hybrid input-output approach that could account for supply-chain energy and emissions by China's building sector. In terms of energy and emission sources, three scopes are defined, primarily aimed at the entire life-cycle of building sector. By dividing the life-cycle into construction, operation, and disposal stages, both scope-based and stage-based analyses are made using domestic statistical data, within the range 1997-2012. The results demonstrate that supply-chain energy and emissions of Scope 3 contribute significantly to the overall life-cycle impacts of building sector, which might be underestimated in a process-based assessment. Although the operation stage appears to be the one with the largest consumption and emissions in the lifespan of a single building, attention should also be paid to the construction stage. The energy and emissions during construction make up the largest share (over 60%) in the life-cycle of the building sector due to the large number of building projects every year. Energy and carbon-intensive components are also evaluated, and possible measures for energy-saving and carbon reduction are discussed. Accordingly, this study provides some useful methods and relevant analysis results, which will be critical for the future of sustainable development of China's building industry.