Hydrogen storage method and system

A system for storing and supplying hydrogen to a hydrogen pipeline at a combined carbon monoxide and carbon dioxide content of less than 10 parts per million, comprising:

• a compressor for compressing a feed stream of the hydrogen to produce a compressed hydrogen feed stream;
• a salt cavern having a residual brine layer located at a bottom region of a salt cavern and side regions extending upwardly from the bottom region of the salt cavern;
• at least one conduit in communication with the salt cavern for injecting the compressed hydrogen feed stream into a salt cavern to produce stored hydrogen within the salt cavern and for withdrawing a stored hydrogen stream composed of stored hydrogen from the salt cavern and without carbon dioxide purification, the at least one conduit having at least one lower end located in an interior region of the salt cavern and spaced above the brine layer and from the side regions of the salt cavern;
• a flow network configured to selectively connect the compressor to the at least one conduit such that the compressed hydrogen feed stream is injected into the salt cavern is injected at an injection ratio equal to an injection flow rate of the compressed hydrogen feed stream to an actual cavern volume of no greater than 7.5 scfd/cf and at an injection velocity of the compressed hydrogen feed stream of no greater than 100 feet per second and the stored hydrogen stream is withdrawn at a withdrawal ratio equal to the withdrawal flow rate of the stored hydrogen stream to the actual cavern volume of no greater than 10.0 scfd/cf and at a withdrawal velocity of the stored hydrogen stream of no greater than 150 feet per second to produce the stored hydrogen within the salt cavern and to selectively connect the at least one conduit to the hydrogen pipeline such that the stored hydrogen stream is injected into the pipeline;
• and
• that salt cavern having at least a minimum quantity of the stored hydrogen within the salt cavern before, during, and between times at which the compressed hydrogen feed stream is injected and at which the stored hydrogen stream.