Abstract: The invention generally relates to a method and system for storing hydrogen product in a salt cavern. The method is directed to substantially confining a high purity hydrogen stored within the salt cavern by maintaining the stored hydrogen at a pressure between a lower limit and an upper limit within the cavern, whereby the salt cavern forms a substantially impermeable barrier to the stored hydrogen therein between the lower limit and the upper limit and wherein the improvement over the predicate art enables the upper limit to exceed about 1 psi per liner foot of cavern depth.

Abstract: A method for storing very high purity hydrogen in a salt cavern is provided. The method includes introducing a compressed very high purity hydrogen gas into a salt cavern, thereby producing a stored very high purity hydrogen gas; maintaining the stored very high purity hydrogen gas at a pressure greater than about 1.0 psi per linear foot of height within the cavern, and less than about 4.0 psi per linear foot of height within the cavern.

Abstract: A method for forming and maintaining a fundamentally impervious boundary to very high purity hydrogen stored in a salt cavern is provided. The cavern includes a salt cavern wall. The method includes introducing a compressed very high purity hydrogen gas into a salt cavern, thereby producing a stored very high purity hydrogen gas; forming a fundamentally impervious boundary to the very high purity hydrogen along at least a part of the perimeter of the salt cavern, and maintaining the fundamentally impervious boundary to the stored very high purity hydrogen gas at a pressure greater than 1.0 psi per linear foot of height within the cavern, and less than 4.0 psi per linear foot of height within the cavern and thereby retaining within the salt cavern over 95% of the stored very high purity hydrogen over a period of time of at least 72 hours.

Abstract: A system for forming and/or maintaining a fundamentally impervious boundary within a salt cavern for storing very high purity hydrogen is provided. The system includes a salt cavern comprising a salt cavern wall; a conduit configured to introduce a compressed very high purity hydrogen gas into a salt cavern, thereby producing a stored very high purity hydrogen gas; the conduit also configured to remove the compressed very high purity hydrogen gas from the salt cavern, wherein the stored very high purity hydrogen gas is maintained at a pressure greater than about 1.0 psi per linear foot of height within the cavern, and less than about 4.0 psi per linear foot of height within the cavern.