Assessing CCS development uncertainties in China's energy system aligned with carbon neutrality

Carbon capture and storage (CCS) plays a pivotal but uncertain role in achieving China's carbon neutrality goal, necessitating a comprehensive assessment of its potential development pathways and implications. This study designs 12 scenarios combining mitigation targets and key uncertainties surrounding CCS, and simulates using a China-localized Global Change Analysis Model (GCAM-CHN) to comprehensively understand the uncertain trajectories of CCS development aligned with China's carbon neutrality. The results show that CCS technologies in China cumulatively capture 36–82 GtCO2 during 2025–2060. Achieving carbon neutrality requires the common but phased contributions of fossil-CCS, bioenergy CCS (BECCS), and direct air CCS (DACCS), with large-scale deployment starting in 2030, 2040, and 2050, respectively. Fossil-CCS serves as a buffer between the carbon-neutral transition and the phase-down of fossil energy, BECCS provides the highest cumulative carbon offsets, while DACCS development exhibits the greatest uncertainty. Given their large emission levels, the coal power, iron and steel, and cement industries are identified to take the lead in CCS deployment. Our scenarios also reveal the interaction between CCS uncertainties and the decarbonization of China's energy system. In the most stringent scenarios that simultaneously exclude bioenergy trade and DACCS, the cumulative abatement costs increase by over 14 % compared to default scenarios.