Les G Armstrong, Bradford H Hager, Sarah Coyle, Kristin D Bergmann, Caitlin Fukumoto, Dharik S Mallapragada

Hydrogen is widely understood to be critical for decarbonizing hard-to-abate sectors like heavy industry, and long-distance transportation as well as balancing a variable renewable energy dominated power grid. Here, we propose a methodology for evaluating the potential for hydrogen storage in geological salt resources. This methodology starts with a characterization of salt resources by considering salt purity and interbedded non-salt lithologies. We then develop a physical model to estimate the storage potential of a cavern, accounting for cavern shape and considering both brittle and ductile failures. We then factor in environmental and safety considerations to develop above-ground exclusion zones. We illustrate this methodology through an assessment of the hydrogen storage potential in the Midwestern and Appalachian regions in the United States. Our results show that the Michigan and Appalachian Salina basins are promising locations for hydrogen storage in salt caverns with a total technical working gas storage potential in Michigan of 2.1 x 109 metric tons of H2 or 69.9 PWh and 1.3 x 108 metric tons of H2 or 4.4 PWh in Appalachia. After applying a coarse techno-economic filter, the storage potential of the remaining high value targets is 9.7 x 108 metric tons of H2 or 32.4 PWh in Michigan and 1.6 x 107 metric tons of H2 or 0.54 PWh in the Appalachian region. These insights can be used to further study the value of these resources for regional decarbonization, while the developed methodology can be readily applied to characterize resource potential in other regions.