Systems for sub-ambient pressure assisted actuation of subsea hydraulically actuated devices and related methods

A system for actuating a subsea hydraulically actuated device, the system comprising:

• one or more subsea reservoirs, each comprising:
• a body defining an interior volume configured to contain an internal pressure that is lower than a pressure of a subsea environment outside of the body, the body defining an outlet in fluid communication with the interior volume;
• where the outlet is selectively sealed;
• and
• a hydraulic power delivery system comprising:
• a rigid sliding member configured to unseal the outlet of at least one of the one or more reservoirs;
• and
• one or more subsea valves;
• where the one or more subsea valves are configured to selectively allow fluid communication between the outlet of the at least one of the one or more reservoirs and a first port of the hydraulically actuated device.

A system for actuating a subsea hydraulically actuated device, the system comprising:

• one or more subsea reservoirs, each comprising a body defining an interior volume configured to contain an internal pressure that is lower than a pressure of a subsea environment outside of the body, the body defining an outlet in fluid communication with the interior volume;
• and
• a hydraulic power delivery system comprising:
• one or more subsea valves;
• where the one or more subsea valves are configured to alternatively allow fluid communication between the outlet of at least one of the one or more reservoirs and a first port of the hydraulically actuated device or a second port of the hydraulically actuated device.