Allocation of CO2 emission target in China under the “1 + N” policy: Considering natural carbon sinks and wind-solar-hydropower endowments

The CO2 emission control targets (CET) allocation faces the unavoidable issues of "energy equity" and "carbon sink equity", which are complicated by changing regional characteristics. By combining regional characteristics assessment, energy consumption status in the "1 + N" policy, and Data Envelopment Analysis (DEA) modeling, two schemes for China's net CET allocation in 2020–2030 are implied to reveal the impacts of regional carbon sinks and renewable energy endowments differences on the allocation. The results indicate that: firstly, significant regional differences are inevitably intrinsic within China's renewable energy endowments and carbon sinks to substantially affect the equity of carbon emission allocation in 2020–2030; secondly Provinces with high fossil energy reliance, such as Hebei, Shandong, Shanxi, and Inner Mongolia, are generally facing continuous pressure to reduce CO2 emissions during the 14th FYP and 15th FYP; thirdly, as a regional ecological advantage, carbon sinks are an essential source of additional carbon budgets for provinces, as in Sichuan and Yunnan. As a dominating impact factor of carbon sinks on CET allocation, terrestrial carbon sinks are much higher than ocean carbon sinks with clear provincial attribution; fourthly, in our allocation scheme, the exploitation of renewable energy endowments directly affects the provincial carbon budget and can promote low carbon energy supply; finally, the foundation to build the CET allocation mechanism, China's carbon market needs to be improved. This study helps policymakers understand and balance the equity issues in CET allocation due to regional differences in renewable energy endowments and carbon sinks.