Technoeconomic Feasibility and Spatial Heterogeneity of Decarbonizing Residential Cooling Across China’s Climate Zones

Accelerating residential building decarbonization is pivotal for China’s carbon neutrality, yet mitigating regional inequalities necessitates localized assessments. To this end, in this study, a stock turnover model is employed to evaluate the spatiotemporal evolution and technoeconomic feasibility of decarbonizing space cooling equipment in China’s urban and rural residential buildings: (1) Urban and rural cooling-related carbon dioxide (CO2) emissions peak in 2022 at 87.2 and 35.9 megatons of carbon dioxide (MtCO2), respectively. (2) Rural cooling energy consumption is projected to peak at 78.0 TWh in 2026, trailing the urban sector by four years, highlighting spatiotemporal decoupling. (3) Decarbonization investments and their benefits exhibit a nonlinear relationship, demonstrating pronounced spatial polarization across climate zones, with the highest decarbonization benefit reaching 86.0 billion CNY in Guangdong Province, whereas carbon-intensive central regions face significant short-term economic deficits. (4) Upgrading urban split air conditioners (ACs) offers a highly viable transition pathway, expected to cumulatively decrease by 142.9 MtCO2 between 2025 and 2060. Overall, this framework establishes a scientific baseline for policymakers to design equitable and cost-effective mitigation strategies within the cooling sector.