Cost-effectiveness analysis of China's Sulfur dioxide control strategy at the regional level: Regional disparity, inequity and future challenges

Sulfur dioxide (SO₂) is still the critical environmental issue in China. The central government adopts the top-down strategy for SO₂ control. However, due to its large size and imbalanced economic development, regional disparity exists and inequity is generated. Under this condition, it requires a region-specific control policy to reach the SO₂ mitigation target effectively and efficiently. To date, there have been few studies in this area. Consequently, this study investigates the regional disparity of SO₂ emission, reduction potential and abatement cost in China's 32 regions by employing the GAINS China model, and analyzes the inequity issues and policy challenges. Results show that up to 2030, applying with flue gas desulfurization (FGD) and limestone injection technology (LINJ), China's SO₂ emissions would be reduced by 51.33% as compared to no policy scenario. Regional disparity is evident in term of reduction potential and unit abatement cost. Regions with larger scale of industry and power generation (e.g. eastern areas) and lower quality of coal (e.g. Heilongjiang province) present a larger reduction potential and lower unit abatement cost. What is more, as the result of the imbalance between middle-western and eastern regions, inequity is highlighted. Certain poor areas (like Guizhou province) have to deal with heavy SO₂ emissions and higher abatement cost per GDP with their limited budgets. Future challenges of promoting cost-effective pollution control strategy considering regional condition are discussed in-depth. Our findings are critical for relative flexible policy making.