CO2 pipeline topologies for Germany – techno-economic assessment of potential future CO2 transport infrastructure

Decarbonizing industry requires solutions for process-related greenhouse-gas emissions that can-not be eliminated through fuel switching or electrification. Carbon capture with utilization or storage (CCUS) is a promising option for hard-to-abate processes. Pipelines are the established mode for high-volume CO₂ transport, but this infrastructure has yet to be planned and globally only a few CO2 pipeline networks are operating.
Here we develop a techno-economic framework that derives CO₂ pipeline networks for varying source, sink and transit configurations. It couples GIS-based least-cost routing and heuristic net-work construction with a mixed-integer program that sets, for a given topology, the transport phase (gaseous or dense), pipe dimensioning, anthe placement and operation of compressors, pumps and liquefiers. Applied to Germany across four scenarios and sensitivities, it yields feasible topologies, their annualized costs, and a robust dense-phase backbone.
We find that onshore transport costs, up to the coastal hubs or onshore storage, range from EUR 29.0 to 41.4 per tonne of CO₂. Two factors dominate: the average transport distance per tonne, minimized by local sinks such as onshore storage or CCU, and economies of scale in pipe diameter, bounded by the 0.7 m dense-phase limit. Robustness depends most on the choice of sources and sinks and on transit volumes. A backbone serving all offshore storage scenarios plus medium transit at up to 70% utilization comprises 5133 km of dense-phase pipeline with estimated CAPEX of EUR 22.0 billion, and transport volume up to 180 Mt/a.
Our results underline the need for a Europe-wide assessment of transit and storage, and suggest a complementary role for vehicle-based transport during ramp-up.