Storage tank comprising—an outer container (2) having a first closable opening (23), and—an inner bladder container (3) disposed within said outer container (2) and having a second closable opening (30), said outer container (2) and inner container (3) being sealed with respect to each other, said inner container (3) being adapted to be filled and or emptied with a liquid through said second closable opening (30), a space (8) between the outer container (2) and the inner container (3) being adapted to be filled with liquid through the first closable opening (23). The outer container (2) is rigid with at least one flexible portion incorporated in the rigid outer container and configured to flex so as to expand and contract to compensate volume variations caused by pressure and or temperature variations to which the storage tank (1) is subjected.

The oxygen tank flotation device is a floating structure adapted for use in recreational water activities. The oxygen tank flotation device is adapted for use with respiratory equipment that is required for use during recreational water activities. The oxygen tank flotation device receives and stores respiratory equipment, such as an oxygen tank, in such a manner that the respiratory equipment will float when the oxygen tank flotation device is placed in a body of water. This arrangement allows the respiratory equipment to float near the user when the user is involved in recreational water activities. The oxygen tank flotation device comprises a vessel, a first float, and a second float.

An underwater energy storage system includes a tank for storing a compressed gas that is adapted to be stored underwater. The tank includes at least one water opening through which water from surrounding environment can flow into and out of the tank, and at least one gas opening through which the compressed gas is received. The underwater energy storage system further includes at least one duct communicating between the at least one opening for gas flow and a source of compressed gas and a compartment constructed over a roof of the tank, wherein said compartment is adapted for receiving weights at a sinking site of the tank.

An underwater energy storage system includes a tank for storing a compressed gas that is adapted to be stored underwater. The tank includes at least one water opening through which water from surrounding environment can flow into and out of the tank, and at least one gas opening through which the compressed gas is received. The underwater energy storage system further includes at least one duct communicating between the at least one opening for gas flow and a source of compressed gas and a compartment constructed over a roof of the tank, wherein said compartment is adapted for receiving weights at a sinking site of the tank.

A modular subsea fluid storage unit comprises a variable-volume inner tank having a rigid top panel and a peripheral wall that is flexible by virtue of concertina formations. The peripheral wall is extensible and retractable vertically while the horizontal width of the tank remains substantially unchanged. A side wall of a lower housing part surrounds and is spaced horizontally from the peripheral wall of the inner tank to define a floodable gap between the peripheral wall and the side wall that surrounds the tank. An upper housing part extends over and is vertically spaced from the top panel of the inner tank and overlaps the side wall to enclose the inner tank. The floodable gap and the upper housing part enhance thermal insulation and trap any fluids that may leak from the inner tank.

A modular subsea fluid storage unit comprises a variable-volume inner tank having a rigid top panel and a peripheral wall that is flexible by virtue of concertina formations. The peripheral wall is extensible and retractable vertically while the horizontal width of the tank remains substantially unchanged. A side wall of a lower housing part surrounds and is spaced horizontally from the peripheral wall of the inner tank to define a floodable gap between the peripheral wall and the side wall that surrounds the tank. An upper housing part extends over and is vertically spaced from the top panel of the inner tank and overlaps the side wall to enclose the inner tank. The floodable gap and the upper housing part enhance thermal insulation and trap any fluids that may leak from the inner tank.

A semi-submersible vessel comprises pontoons having a generally five-sided transverse cross section. In the case of a 4-sided semi-submersible, the columns may be arranged in a generally rectangular form with a column at each corner of the rectangular form, each column having with four sides disposed at a right angle to at least one adjacent side and a fifth side on the exterior of the generally rectangular form disposed at 45 degrees to each adjacent side.

A subsea container is for housing an electronic module. In an embodiment, the subsea container includes a main body including an opening; a module frame for receiving an electronic module that is to be arranged inside the main body; a support structure for supporting the module frame within the main body; and a lid fitting the opening of the main body, the support structure including a shock absorbing structure. Further, a method of manufacturing a subsea container is described.

A subsea container is for housing an electronic module. In an embodiment, the subsea container includes a main body including an opening; a module frame for receiving an electronic module that is to be arranged inside the main body; a support structure for supporting the module frame within the main body; and a lid fitting the opening of the main body, the support structure including a shock absorbing structure. Further, a method of manufacturing a subsea container is described.

An installation for the in-port storage of liquid fuel, which is formed near a dock, is formed of at least an upper surface substantially parallel to the free surface of the sea and a frontal surface adjacent to the upper surface and partially immersed. The installation includes at least one module having a floating caisson containing a fluidtight tank that may contain liquid fuel and having a closed contour formed of an upper face, a lower face, and several lateral faces. The module is fixed to the dock by anchoring means connecting one of the lateral faces of the caisson to the frontal surface of the dock, the lower face and the lateral faces of the caisson therefore being at least partially immersed.