Life cycle carbon emissions of two residential buildings in China: Comparison and uncertainty analysis of different assessment methods

Life cycle assessment of building carbon emissions has drawn great attention recently, due to the policy of controlling the greenhouse effect. Various approaches including process-based method, input-output analysis, and hybrid method have been applied for the assessment. Hence, with the purpose of achieving a comprehensive comparison of these approaches, the present study made a comparative analysis in light of the uncertainties in parameter, scenario, and modeling. Based on the life cycle assessment of two residential buildings, both deterministic and stochastic analyses were conducted to quantify the differences and relevant uncertainties in the emissions by different assessment methods. The results indicated that the choice of methods had significant influences on the calculated emissions, which ranged from 3.3 to 3.6 tCO(2e), per floor area for the two buildings. With consideration of the parameter uncertainty, pure input-output analysis could lead to considerable errors, and hybrid methods were recommended in the emission assessment. Furthermore, based on the analysis of defined scenarios, scenario and model uncertainties were evaluated and compared for different assessment methods. Overall, the findings and suggestions could be helpful for understanding the differences and uncertainties in the results of carbon emission assessment, and therefore benefit the quantification of building emissions. (C) 2020 Elsevier Ltd. All rights reserved.