Geological carbon dioxide storage in the German North Sea: Static‐to‐dynamic capacity refinement for a 10 Mt/y injection scenario

This study evaluates the site‐specific CO 2 storage capacity and large‐scale injectivity performance of a potential saline aquifer CO 2 storage site in the German North Sea sector. A high‐resolution 3D geological model of the Triassic Volpriehausen sandstone is used to estimate static storage capacity via a spill‐point analysis and to refine these estimates through dynamic reservoir simulation. The injection scenario targets 300 Mt CO 2 over a 30‐year period at a rate of 10 Mt/year, followed by a 100‐year postinjection phase. The static assessment indicates a total storage capacity of approximately 900 Mt at the site, but the dynamic simulations show that only a fraction of this capacity is actually achievable under these high‐rate requirements. Dynamic simulations confirm that the 10 Mt/year target can be sustained using five vertical wells positioned near the structural spill depth. The injection rate could also be achieved using two horizontal wells with two or three open sections, furthermore allowing for steering of the injected CO 2 phase towards individual subtraps. Injection strategies are tested under realistic site‐specific boundary conditions, accounting for pressure dissipation, fracture limits, and plume confinement. Pressure build‐up is found to extend across tens of square kilometers. CO 2 may partially remain in the mobile phase for 100 years after the end of the injection.