Historical peak situation of building carbon emissions in different climate regions in China: Causes of differences and peak challenges

The climatic conditions in different regions of China are complex and diverse, and the characteristics of building energy consumption in different climatic regions are quite different, leading to significant differences in the historical peak situation of building carbon emissions (BCE). Based on the statistical Mann–Kendall (MK) trend test method, this study evaluates the historical peak situation of BCE in different climate regions in China and discusses the reasons for the differences in the growth trends and peak situations of BCE in these regions. Furthermore, according to the characteristics of building energy consumption in different climate regions, the challenges faced by each climate region in promoting the peaking of BCE are highlighted. The research results show that owing to the continuous increase in the proportion of electrification and clean energy power generation, the electricity emission factor and carbon emissions per unit of energy consumption continue to decline, and the growth rates of BCE in the transitional and southern regions are significantly lower than the growth rate of building energy consumption, and the carbon emissions per unit floor area in the southern region has reached its peak. The main obstacles to promoting the peaking of BCE in the northern heating region are the high‑carbon heating energy structure and the unrestrained heating behavior of residents, while the challenges faced by the transitional and southern regions are the southward migration of the population and economic centers of gravity and the gradual increase in residents' requirements for living environment comfort. Government decision-makers should formulate differentiated BCE peaking strategies according to the characteristics of building energy consumption in different climate regions.