Tethered submarine pressure transfer storage facility for liquified energy gases

An improved offshore submarine storage facility in the ocean and like water bodies for storing liquified energy gases and similar liquid materials under pressure and at cryogenic temperatures is disclosed. The facility includes a two-part insulated submarine storage tank positioned at a selected depth in the water for storing said materials, wherein the two parts thereof move in a slidably sealing engagement relative to each other to form an insulated compression storage chamber. The tank also includes ambient water pressure transfer means for transferring external ambient water pressure to the materials stored therein. Mechanical pressure transfer devices increase the pressure applied to the materials stored therein to achieve a total pressure which promotes and aids maintenance of liquid state of the stored cryogenic materials. The tank further includes an extensible, seawater impermeable membrane extending between said two parts to form an enclosed space to seal off seawater from surfaces of said parts which slide relative to each other in sealing engagement. A balancing fluid is disposed in said enclosed space at a pressure equalized with ambient seawater pressure for providing further thermal insulation and for isolating the sealing surfaces from contact by seawater throughout the range of slide movement of the two parts of the storage tank. A balancing fluid recirculation jacket surrounding the tank provides another aspect of the present invention.