Subsurface gas storage system

A subsurface gas storage system, comprising:

• a storage pod comprising a plurality of storage modules suspended from a support plate into a well bore, each of the storage modules comprising a rigid outer casing which surrounds a rigid inner liner to define a sealed interior gas storage space within the inner liner and a sealed annulus space between the inner liner and the outer casing, wherein the sealed interior gas storage space of each of the plurality of storage modules is placed in fluidic communication to provide a combined storage space, wherein the sealed annular space of each of the plurality of storage modules is placed in fluidic communication to provide a combined annulus space, and wherein the combined annulus space filled with a fluid comprising a non-compressible liquid;
• and
• a differential pressure control mechanism configured to maintain a differential pressure across the inner liner within a predetermined differential pressure range, the differential pressure constituting a difference between an annular pressure of the fluid within the combined annulus space and a storage pressure of gas within the combined storage space, the differential pressure control mechanism comprising at least one pump configured to recirculate the fluid within the combined annulus space and at least one pressure relief valve configured to release the fluid from the combined annulus space.