Multi-dimensional building carbon emissions echelon peak target setting in China based on building types, sources, and indicators

Building carbon emissions peak is not an independent and single process but the result of the joint action of multiple objects and targets. Therefore, the single target of building carbon emissions peak should also be split into dimensional and phased peak targets with both differentiation and unity to realize carbon peak in the building sector gradually. To achieve this goal, this study constructs a building carbon emissions peak target (CEPT) setting model based on the principle of objective optimization using scenario analysis and Monte Carlo simulation, and applies the model to the Chinese building sector to fully refine the building CEPT in terms of building types, emission sources, and emission indicators, as well as to develop a more detailed carbon peak roadmap. The results show that, except for carbon emissions from commercial buildings (peak time t31=2031), per capita carbon emissions of buildings (t23=2032), and electricity carbon emissions (t22=2034), all other objects can achieve a carbon emissions peak by 2030. Moreover, the building CEPTs under different dimensions follow a pattern of echelon peaking with an apparent order of priority. In addition, under the low-carbon scenario, China will achieve the carbon peak in the building sector by 2029, which suggests that China's building sector should make greater efforts and promptly take more effective measures to ensure the achievement of the 2030 carbon peak target. The building CEPT setting model proposed in this study can provide important support for developing a phased action plan for energy conservation and emission reduction.