Magnum’s domal salt caverns provide the ideal environment for bulk storage of hydrogen gas safely and economically for a range of utility, industrial, and commercial purposes. The caverns will be purpose built, provide a sturdy impermeable container that will not leak, and operate for decades.
A salt cavern effectively operates like a scuba tank—it is filled, stored under closely controlled pressure conditions, and then emptied as required. Unlike storage technologies such as depleted oil and gas reservoirs and aquifers, this storage process can be carried out economically and continually without product loss while preserving the integrity of the storage medium.
To fill the cavern, off-peak or excess renewable electricity is used to electrolyze water and produce “green” hydrogen gas. Green hydrogen can be produced, for example, using wind and solar power that would otherwise be curtailed, then stored underground and drawn upon to help meet power needs during times of peak demand—effectively acting as a grid battery. Salt caverns can store enough green hydrogen to shift spring surplus to summer peaks and/or fall surplus to winter loads. Alternatively, the gas can be stored for later distribution to hydrogen markets for manufacturing or transportation.
Salt caverns such as Magnum’s are rare in the West but a proven technology for hydrogen storage. Caverns have been used safely for storage in the U.S. since the 1980s. They provide the opportunity for storage of significantly greater volumes—in Magnum’s case, energy equivalent to approximately 1 million barrels of oil (see figure below)—than would be practical in above-ground tanks and at significantly lower cost.