Cost-Effectiveness of NO X and VOC Co-operative Controls for PM 2.5 and O 3 Mitigation in the Context of China’s Carbon Neutrality

Co-operative controls of NO X and VOC are increasingly emphasized to mitigate both PM 2.5 and O 3 pollution in China. Given the substantial reductions in air pollutants expected under carbon neutrality, both PM 2.5 and O 3 concentrations will ultimately decrease to low levels regardless of co-operative controls. Therefore, understanding the cost-effectiveness of co-operative controls in the context of carbon neutrality is critical to enhance the feasibility of implementing relevant policies. Here we evaluate the control costs and health benefits under four co-operative control strategies. We show that adopting co-operative controls in megacity clusters can generate significant net benefits (health benefits minus control cost), such as Beijing-Tianjin-Hebei and its surroundings (net benefits: 0.23 trillion USD) and the Yangtze River Delta (net benefits: 0.12 trillion USD), while the merit of adopting co-operative controls nationwide is unnoticeable. Furthermore, these benefit increments induced by co-operative controls are not considerable compared to the benefits induced by carbon neutrality itself. The role of co-operative controls deserves reconsideration in alignment with carbon neutrality, with a focus on some specific regions rather than uniform implementation across all cities.