Study on Carbon Emissions from the Renovation of Old Residential Areas in Cold Regions of China

With the implementation of dual-carbon and new human-centric urbanization strategies, the renovation of old buildings in China was inevitable. In this study, we establish the carbon emission values of retrofitting building from the perspective of carbon emissions, and propose a carbon accounting calculation method. Meanwhile, according to an economic viewpoint, we propose carbon emission evaluation indexes, including carbon increments, carbon emission intensity, carbon saving during the operation phase, and the static payback period of carbon increments. We retrofitted a building in an old residential area in Jinan, which both extended the building’s life and met the energy consumption needs of modern buildings. Through the case study, the annual carbon emissions during the use phase were reduced by 80.64% after retrofitting, and the building materials generated carbon emissions during the materialization phase of 11.04 t CO2/a. Considering the carbon increment factor, the comprehensive carbon emission reduction was 71.43%. The carbon increment per unit of building area was 110.32 kg CO2/m2, of which the carbon emission during the materialization stage accounted for 96.04%. Promoting low-carbon building materials and improving the energy efficiency would be an important means to reduce the carbon increments during building renovations. The static payback period for the carbon increment was 2.05 years, indicating that retrofitting measures were effective. Our work is informative for the development and quantitative assessment of low-carbon retrofitting programs for older buildings.