Assessment of hydrogen storage capacity in porous media at the European scale

A first assessment of the storage resource at European scale for underground hydrogen storage in porous media is presented for the European Union and some neighboring countries (Norway, Turkiye, Ukraine, United Kingdom). The study includes different types of porous media: existing underground gas storages, depleted oil and gas fields, deep saline formations. The storage resources are computed based upon a volumetric analytical approach which accounts for hydrogen physical characteristics (density, viscosity, sweep efficiency and capillary trapping). The computed storage resource is in good agreement with published dynamic storage capacity of deep saline formations in Poland. The extension to the continental scale enables a consistent estimate of the various storage resources. The working storage resources at the European scale are about 8000 TWh among which 37 % are onshore which covers the expected storage requirements. The agreement with previously published working storage capacities for depleted gas fields in the UK continental shelf is quite good at about 2662 TWh. However, at the field level, there might be significant differences linked with the consistency requirements at European scale of this study which estimates the production of oil and gas fields without using the actual field production. Despite its restriction of publicly available data, these results show significant storage resources. The working capacities are not evenly distributed over the continent. However, assuming no competitive usage, the working storage resource would be extremely significant when accounting for onshore and offshore potential. Amongst the different porous media, the underground gas storages present the most interest for conversion to hydrogen underground storage despite their smaller storage resource, 460 TWh, than for depleted gas fields, 5440 TWh for the onshore and offshore. The estimate of working storage resource in deep saline formation is quite low, only 46 TWh as it relies upon traps that were previously characterized.