A Preliminary Geomechanical Study of Underground Hydrogen Storage in the Inyan Kara Saline Aquifer in the Williston Basin

Hydrogen, as a low-carbon energy carrier, presents a promising solution for energy storage, especially to counterbalance the variability in renewable energy sources. This investigation evaluates the feasibility of underground hydrogen storage within saline aquifers, with an emphasis on the Inyan Kara formation located in the Williston Basin, North Dakota. Through a 3D hydro-mechanical simulation, the study explores both the capacity of this specific aquifer for hydrogen containment and the consequent hydraulic and geomechanical impacts of multiple hydrogen injection and extraction cycles. The adopted methodology seamlessly integrates a comprehensive 3D geomechanical model with invaluable field data, such as formation pressure measurements and insights derived from density and acoustic logs. Preliminary outcomes suggest a favorable recovery rate, with an estimated 76% of the injected hydrogen being retrievable in a 3 months injection-3 months production framework. Further, by employing the Mohr-Coulomb failure criteria and one-way coupling scheme, the research underscores the robustness and safety of this underground storage technique, emphasizing its potential in harmonizing renewable energy fluctuations.