Patent ID: 8240956

Claim:
A bladder module for receiving, storing and discharging compressed air, the bladder module for deployment in an energy accumulator system, the bladder module comprising: a variable volume bladder for subjection to an ambient hydrostatic pressure when disposed underwater, the variable volume bladder configured for ingress and egress of compressed air via an interconnection pipe assembly having a shutoff valve, the variable volume bladder made buoyant when storing compressed air at substantially the ambient hydrostatic pressure, the variable volume bladder oriented substantially longitudinally about a vertical axis when made buoyant by ingress of compressed air thereinto, in the underwater disposition; and a tether assembly anchoring the variable volume bladder made buoyant in the underwater disposition, the tether assembly including a buoyancy thrust sensor in wireless communication with the shutoff valve, wherein a reduction in buoyancy thrust of the bladder module activates the shutoff valve to pre-empt free-flow of compressed air from the interconnection pipe assembly.