LMDI-Tapio analysis and scenario-based carbon emission reduction pathways for the southern power grid region in China: insights from comparative reference regions

Decarbonizing regional power systems is essential for achieving China’s carbon-neutrality targets. However, analyses conducted only at the national or provincial level may overlook the functional interdependence among electricity demand, generation structure, and cross-provincial power transfers. This study examines the southern power grid region in China, which includes Guangdong, Guangxi, Guizhou, Yunnan, and Hainan, as an integrated electricity system rather than as a simple geographical or administrative unit. This region provides a useful case because it combines energy-intensive coastal demand centers with inland provinces that are rich in hydropower and renewable energy resources. It therefore allows an assessment of whether regional grid integration can support the decoupling of economic growth from electricity-sector carbon emissions. Using data from 2013 to 2021, this study develops a sequential analytical framework that combines decomposition analysis, decoupling assessment, and constrained scenario modelling. The decomposition–decoupling results indicate that the southern power grid region remained mainly in a weak decoupling state during the study period. Although improvements in electricity efficiency and changes in the generation structure contributed to emission reduction, their effects were partly offset by rapid economic growth and continued reliance on fossil-fuel power generation. In the Region A decomposition dataset, several strong-decoupling years coincided with declines in the fossil-fuel power generation ratio. Scenario projections show that, under the Normal-scenario assumptions, electricity-sector carbon emissions in the southern power grid region may peak around 2036. Under a more stringent decarbonization pathway aimed at achieving net-zero emissions by 2050, the peak could be advanced to 2033, with a projected peak of approximately 599.9 Mt, 25.4% below the Normal-scenario peak of approximately 803.7 Mt. These findings suggest that, alongside renewable-capacity expansion, policy strategies for the southern power grid region could place greater emphasis on enabling the actual displacement of fossil-fuel generation. Cross-provincial coordination, dispatch arrangements, and regulatory alignment may support this process, although the effects of these individual policy measures are not separately estimated in this study.