Optimizing the deployment timing of carbon dioxide removal (CDR) in China: A holistic assessment under the carbon neutrality target

As the world’s largest developing-country emitter of CO₂, China requires carbon dioxide removal (CDR) to offset residual emissions. Existing literature predominantly focuses on the scale of CDR deployment while insufficiently addressing the critical role of deployment timing. Based on GCAM v7.1, this study compares two scenarios in which CDR deployment begins in 2035 or 2065 under a global 1.5°C pathway and China’s Nationally Determined Contributions, without imposing an upper limit on CDR deployment. Results reveal that unrestricted CDR expansion creates systemic pressures on China’s energy, land, and water systems. Delaying CDR until 2065 increases reliance on negative-emission technologies, constrains renewable energy and carbon capture and storage (CCS) expansion, increases fossil-fuel dependence, and slows electrification, thereby intensifying risks to ecological, food, and water security. By contrast, initiating CDR in 2035 distributes decarbonization pressure more effectively and reduces cumulative mitigation costs through 2100. Under this pathway, non-fossil energy reaches 52.19% of primary energy consumption by 2060. Delayed deployment also narrows the mid-century mitigation window, exacerbates persistent cropland shortages, and substantially increases long-term carbon prices. These findings highlight the critical role of CDR timing in balancing mitigation costs, energy transformation, and resource security, informing China’s long-term low-carbon policymaking.