Interprovincial Heterogeneity in Decarbonization Pathways: Spatiotemporal Evolution of China's Power System Toward Carbon Neutrality

Accelerating the decarbonization of power systems is crucial for achieving China's carbon neutrality goals and mitigating global warming. Considering the carbon neutrality targets and temperature limits set by the Paris Agreement, three carbon neutrality scenarios—NDC (Nationally Determined Contribution), CN2055 (Accelerated Decarbonization), and GM1.5 (Global 1.5°C Temperature Control)—were developed. The Global Change Analysis Model (GCAM) was used to quantitatively assess carbon emission pathways, energy transformation, and power generation costs across different scenarios. The spatial and temporal variations, along with the dynamic trends in carbon emissions and power systems across 31 provinces of China from 2025 to 2060, were systematically analyzed. The results indicate the following: (1) Emission reduction pathways vary significantly across different scenarios. Carbon emissions in the NDC scenario peaked in 2030 and then declined. The CN2055 scenario reached its peak earlier and accelerated decarbonization. The GM1.5 scenario reached nearzero emissions by 2050. (2) Low-carbon emissions are concentrated in inland regions, particularly the west, while high-carbon emissions are predominantly found in the eastern coastal areas. This contrast diminishes over time. (3) The proportion of nonfossil energy increased from 45% to 82%, coal power decreased to 16%, and wind and solar power collectively contributed over 56%. (4) The Environmental Kuznets Curve (EKC) suggests that the eastern region reached the EKC turning point earlier, while the central and western regions benefited from the “late-mover advantage” and achieved emission reductions with a lower economic threshold. (5) Increased clean energy penetration will lower power generation costs, while moderate power demand growth can significantly reduce future total costs. The findings provide valuable insights for decision-making regarding the low-carbon transformation of China's power system and offer implications for other countries striving to achieve carbon neutrality goals.