Abstract
Underground hydrogen storage (UHS) in geological formations (aquifers, salt caverns, and depleted reservoirs) is a promising large-scale solution, with capacities reaching terawatt-hours. Depleted reservoirs are especially suitable due to well-characterized geological structures, existing wells and surface facilities, reduced cost of field exploration and decommissioning, lower investment cost, and proven sealing capabilities.
To assess the feasibility of offshore UHS in Norway for powering platforms with renewables, interdisciplinary research has been conducted under the HyStorm project and the Hydrogeni FME Centre, combining experimental and modeling approaches to evaluate H2 storage potential in depleted offshore reservoirs.
This paper summarizes completed and ongoing work within these projects, focusing on hydrogen storage in depleted oil and gas reservoirs. The studies include:
1. Evaluation of the hydrogen storage potential of shut-down fields on the Norwegian Continental Shelf.
2. Phase behaviour and black-oil simulations to model fluid dynamics in reservoir systems.
3. Hydrogen sorption/desorption experiments on clay minerals and shale caprocks.
4. Measurements of hydrogen and hydrogen-methane mixture viscosity for flow characterization.
5. Risk assessment of legacy wells and their potential impact on storage security.
6. Long-term reservoir sandstone and caprock shale exposure experiments, followed by post-exposure analysis using gas chromatography, XRD, and acoustic/rock mechanical tests.