EGU23-1909, updated on 04 May 2023
EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Microbial Risk Assessment for Underground Hydrogen Storage in Porous Rocks

Eike Marie Thaysen1, Timothy Armitage2, Lubica Slabon2, Aliakbar Hassanpouryouzband2, and Katriona Edlmann2
Eike Marie Thaysen et al.
  • 1Institute for Environmental Assessment and Water Research, National Spanish Research Council, Carrer Jordi Girona 18-26, 08034 Barcelona, Spain
  • 2School of Geosciences, Grant Institute, The King's Buildings, The University of Edinburgh, James Hutton Road, Edinburgh, EH9 3FE, United Kingdom

Climate change, triggered by a continuously rising use of carbon based energy sources, is a global concern. Geological hydrogen storage, e.g. in depleted gas fields or saline aquifers, can overcome imbalances between supply and demand in the renewable energy sector and facilitate the transition to a low carbon emissions society, in this way mitigating climate change. However, a range of subsurface microorganisms utilise hydrogen which may have important implications for hydrogen recovery, clogging and corrosion. We created a novel, globally applicable risk categorization tool based on the published environmental growth constraints of all major hydrogen utilizing microbes (hydrogenotrophic methanogens, hydrogenotrophic sulphate reducing bacteria, homoacetogens and hydrogenotrophic dissimilative iron reducing bacteria) and on reports of paleosterile subsurface environments. Application of the tool to 75 depleted or close to depleted gas fields on the UK continental shelf showed that 9 fields fall either within the ´No Risk´ category with temperatures >122 °C, making them the ideal candidates for hydrogen storage from a microbial risk point of view. Hydrogen storage in the 35 ´Low Risk´ fields with temperatures >90 °C or the 22 ´Medium Risk´ fields with temperatures >55 °C and salinities >1.7 M NaCl will require the careful characterization of the microbial community composition to assure that hydrogenotrophic microorganisms are not present. We recommend against utilising depleted gas fields with temperatures <55 °C which are at high risk for adverse microbial effects. 

Results were mapped and aligned with centres for renewable energy production and out-of-use pipelines suitable for repurposing to transport hydrogen. This showed that No Risk or Low Risk depleted gas fields in the Southern North Sea are the most suitable candidates for hydrogen storage. Our results advise site selection choices in geological hydrogen storage in the UK. Our methodology is applicable to any underground porous rock system globally.

How to cite: Thaysen, E. M., Armitage, T., Slabon, L., Hassanpouryouzband, A., and Edlmann, K.: Microbial Risk Assessment for Underground Hydrogen Storage in Porous Rocks, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-1909,, 2023.