Two-level allocation and its future change of CO2 reduction responsibility in China's power sector

Promoting the low-carbon development of the power sector is an important means for China to achieve the emissions peak and carbon neutralization targets, while the rational allocation of emission reduction re-sponsibility is the prerequisite for low-carbon electricity. This paper proposes a two-level mechanism to allocate CO2 emission reduction responsibilities based on the principles of fairness, efficiency and sustainability. First, a graph game model considering the distribution of regional resources and mutual cooperation is established to initially allocate national emission reduction responsibilities to 8 regions in 2019. Then, taking the inter-provincial transfer of CO2 emissions into consideration, the Game-theory combination weighting method is used to allocate the regional responsibilities to corresponding provinces. The results show that the Southwest has the least responsibility (-0.24%), while the North and East are responsible for +28.66% and +26.64%, respectively. At provincial level, Inner Mongolia (+10.13%), Shandong (+8.56%), Jiangsu (+8.16%) and Hebei (+7.12%) have a greater responsibility for emission reduction, while the provinces with the least responsibility are Chongqing (-0.06%) and Sichuan (-0.18%). To further explore how the responsibility will change in the future and what can be improved for each province, three scenarios are set up to allocate the responsibility in 2025, 2035 and 2050, and highlight the changes during the 14th Five-Year Plan period. If the growth rate of power demand increases, the responsibility of Northwest (+0.89%) will increase most compared to BAU, among which Xinjiang (+0.26%) and Ningxia (+0.23%) with low efficiency and unclean power generation will significantly bear more responsibilities. If the non-fossil growth rate increases, the large-scale electricity con-sumers such as East (+0.27%) and North (+0.25%) will show the largest change, with Jiangsu and Shandong account for +0.09% and +0.08%, respectively.