Growth-limited or pressure-limited? Evaluating CCS scale-up trajectories in the UK

All pathways provided by integrated assessment models to mitigate climate change suggest large-scale deployment of carbon capture and storage (CCS). The projected storage rates would approach several gigatonnes per year, which entails a massive scale-up of the current industrial practice. Yet these projections are often poorly constrained by both the pace at which CCS infrastructure can expand and geophysical limits on the optimised and safe use of subsurface storage resources. We here present a modelling framework that integrates these constraints into the assessment of CCS scale-up trajectories, with a focus on the offshore UK. We represent CCS deployment pathways consistent with national climate goals using logistic growth models, capturing the characteristic evolution of large-scale resource use systems. We use simplified physics models for screening pressure-limited regional CO₂ storage capacity. The combined framework enables allocating storage resources across offshore UK saline aquifers. Our analysis reveals substantial UK offshore storage capacity capable of supporting highly ambitious CCS deployment scenarios without violating geophysical constraints. Across a wide range of geological uncertainties and storage allocation strategies, CCS growth is unlikely to be limited by the reservoir injectivity or storage capacity. However, deployment pathways characterised by more gradual growth and longer injection lifetimes are more consistent with sustainable resource use, reducing the number of high-rate injection hubs and preventing localized pressurisation. Comparison with historical hydrocarbon development in the North Sea suggests that the required storage infrastructure is technically achievable, contingent on supportive economic and regulatory conditions. Overall, our results support the feasibility of rapid, CCS-enabled decarbonization in the UK, provided that policy, investment, and industrial capacity scale in line with climate ambitions.