Prediction of embodied GHG emissions of building materials in Shanghai

The construction sector stands as a fundamental component of urban development, providing indispensable spaces and infrastructure critical to societal demands. However, the consumption of considerable building materials engenders a significant environmental footprint, mainly from the exploitation, manufacturing, and processing. Characterizing the dynamic changes in a city’s future building development and material demand is crucial for achieving the goal of carbon neutrality. As an international metropolis, Shanghai faces challenges, including limited land and resources, high population density, and rapid building renewal rates. Understanding building renewal patterns and developing potential urban mineral resources will help alleviate resource shortages, achieve sustainable use of building materials, and meet carbon reduction goals. Taking Shanghai as a case study, this research applies material flow analysis alongside the carbon emission factor method to forecast the consumption of building materials and the associated embodied carbon emissions within the city. The study meticulously quantifies the evolving patterns of building material consumption and embodied carbon emissions from 2023 to 2060. The results indicate that Shanghai's civil building stock area will undergo incremental growth, attaining a pinnacle in 2030 before embarking downward. In contrast, the scope of new construction and demolition within the urban fabric will follow an ascending trend throughout the same period. Regarding material consumption, gravel, cement, and bricks are identified as the predominant components, accounting for 58%, 18%, and 15% of the total material inflow, respectively. Embodied carbon emissions from Shanghai’s civil buildings are anticipated to rise steadily, mirroring the pattern of material consumption. Notably, emissions from residential buildings are expected to experience a slight decline from 2023 to 2028, ultimately reaching 5.43 Million metric tons (Mt) in 2060. The insights garnered from this research are instrumental in deepening the comprehension of urban development dynamics and the intricacies of resource management.