Decarbonizing China's aluminium industry: a comprehensive assessment of synergistic carbon capture, utilization, and storage with renewable energy technologies

As both an indispensable enabler of clean energy transition and one of decarbonizing hard-to-abate sectors, the aluminium industry sits at the heart of a deep industrial contradiction that is particularly acute in China, which accounts for nearly 60% of global production. A bottom-up plant-level database covering 262 production lines was developed, and the Aluminium Carbon Capture, Utilization and Storage (CCUS) & Renewable Energy (RE) Synergy Optimization model (Al-CRESO) was constructed to systematically assess the decarbonization potential, pathways, and economic competitiveness of China's aluminium industry from 2030 to 2060.The results reveal a structural duality in current industry emissions, with direct emissions (321.76 MtCO₂) and indirect emissions (263.17 MtCO₂) contributing almost equally, indicating that neither CCUS nor RE substitution alone can achieve near-zero. The synergistic deployment scenario unlocks approximately 9130 MtCO₂ of cumulative emission reductions from 2030 to 2060, 2.2 times that of CCUS-only deployment (4200 Mt) and nearly 5 times that of RE-only substitution (1900 Mt). Economically, synergistic deployment reduces total CCUS net costs by 63.76% and compresses median marginal abatement costs by up to 49%. Sensitivity analysis confirms the system's resilience to renewable energy price volatility while revealing pronounced sensitivity to crude oil prices and CCUS engineering costs. The proposed framework offers a transferable methodology for decarbonizing aluminium industries globally and provides actionable guidance for policymakers navigating the transition toward carbon neutrality.