Avoiding overestimations of mitigation potential and costs of CCUS in China’s steel industry

Abstract Carbon capture, utilization, and storage (CCUS) is promising for carbon neutrality vision in steel industry. Previous work has overestimated both mitigation potentials and economic costs, hindering the long-term planning of CCUS. Here, we propose a soft-linking approach, combining the industry decarbonization pathway and emission source-sink matching models, to avoid both overestimations in China’s steel industry. Results show the emissions of China’s steel industry are estimated to decrease by 38.9-55.2% under three scenarios before retrofitted by CCUS. The optimized CCUS layouts have mitigation effects of 438.01-529.02 Mt, meeting the requirements of the industrial –level decarbonization pathways. The specific costs of CCUS are 138-150 CNY/t, 29-65% lower than the unselected sources. CCUS will increase the energy and water consumption by 25%+ with uneven distribution, exacerbating local resource scarcity problems. The methodology and findings can clarify the mitigation effects and costs of the CCUS technology to set proper long-term planning for its promotion.