Subsea pressure systems for fluid recovery

A method for recovering power fluid from a device under water and for continuously pumping recovered power fluid to a surface of the water, the method comprising:

• flowing fluid from a subsurface apparatus to a subsurface recovery system,
• the fluid initially provided to the subsurface apparatus to power the subsurface apparatus;
• the subsurface recovery system including pump apparatus for selectively pumping recovered fluid to a fluid container above a surface of the water;
• selectively providing fluid to the pump apparatus for pumping to the surface;
• providing a constant flow of fluid under pressure from a subwater accumulator system to maintain a negative internal pressure in the pump;
• and wherein the pumping of fluid to the surface is continuous wherein a first reserve capacity apparatus selectively provides fluid to the first chamber or to the second chamber;
• and
• a second reserve capacity apparatus selectively provides fluid to the second chamber or to the first chamber;
• the method further comprising selectively providing fluid to the first chamber or to the second chamber from the first reserve capacity apparatus;
• and
• selectively providing fluid to the second chamber or to the first chamber from the second reserve capacity apparatus.

A system for recovering power fluid from a device under water and for pumping recovered power fluid to a surface of the water, the system comprising

• a subsurface recovery system including pump apparatus for selectively pumping recovered fluid to a fluid container above a surface of water,
• the pump located for receiving fluid from a subsurface apparatus to a fluid initially provided to the subsurface apparatus to power the subsurface apparatus;
• reserve capacity apparatus for receiving fluid from the subsurface apparatus and
• selectively providing the fluid to the pump apparatus to be pumped to the surface;
• and pump valve apparatus for controlling fluid flow to the pump,
• wherein a first reserve capacity apparatus selectively provides fluid to the first chamber or to the second chamber;
• and
• a second reserve capacity apparatus selectively provides fluid to the second chamber or to the first chamber;
• the method further comprising selectively providing fluid to the first chamber or to the second chamber from the first reserve capacity apparatus;
• and
• selectively providing fluid to the second chamber or to the first chamber from the second reserve capacity apparatus.