A support structure for an offshore device is provided, including a vertical guide sleeve and three elongated guide sleeves positioned around the vertical guide sleeve, and various braces connecting the elongated sleeves and the vertical guide sleeve. The support structure also includes a transition joint including a cylindrical portion for connection to an offshore device, such as a support tower of a wind turbine assembly, and a conical portion connected to the vertical guide sleeve. To provide resistance to thrust, bending, and torsional fatigue, at least one set of braces is formed in an oval, racetrack, obround, or stadium configuration, and one or more horizontal stiffeners are positioned in the transition joint to maximize the strength of the support structure.

A method for selectively coupling or uncoupling a coupling with a release, arranged between the supply conduit and a cylinder, on the basis of pressure in a supply conduit. The method includes providing an operating pressure prevailing in the supply conduit in order to provide hydraulic liquid to the cylinder on the basis thereof, and providing an uncoupling pressure prevailing in the supply conduit for the purpose of activating shut-off valves in the supply conduit and on the cylinder, and activating a release which uncouples the coupling. A coupling for respectively coupling and uncoupling a supply conduit which is connected to the coupling to/from a cylinder, as well as to an assembly including a pump, a cylinder, a supply conduit between the pump and the cylinder, and such a coupling.

An offshore power generating system has a buoyancy body shaped as a hull with a bow and aft end, and elongated mast extending up from the buoyancy body to the buoyancy body about a horizontal transverse axis. A rotor is supported in one end of the longitudinal mast for rotation about a horizontal axis. The buoyancy body is kept in position with the bow turning up into wind and incoming waves. Rotational support of the mast has a horizontal rotational axis through the center of gravity of the mast that lies in the center plane of the buoyancy body above the aft end when the buoyancy body lies in operational position in calm sea with the rotational axis of the rotational support of the mast orthogonal to the center plane of the buoyancy body. A method for on-board loading and commissioning of mast with installed rotor on-board a buoyancy body.

A structure for mounting offshore installations such as wind turbines or oil and gas platforms. The structure comprises a base, a top piece, and a lattice structure connecting the base to the top piece. The sub-components of the structure can be pre-assembled prior to installation to facilitate ease of construction, or they may be transported to a pre-determined location and assembled on site.

A node structure (12, 14) for connecting two or more convergent members (16, 26) of a lattice frame to each other and to one or more other members of the lattice frame. The node structure (12, 14) comprises a pair of opposed spaced-apart faces (30) that are substantially planar and substantially parallel to each other. At least one pair of root formations (32) with respective central longitudinal axes define an interior angle between them, those axes diverging outwardly for alignment with respective members of the lattice frame and converging inwardly between the faces (30). An inner connecting wall (34) between the root formations (32) of the pair connects concave-curved inner edges (36) of the faces and extends in a concave curve around the interior angle to join the root formations (32) of that pair.

Provided is a method of installing a transmission cable arrangement of an offshore wind turbine, including step of providing a cable protection assembly, wherein provision of the cable protection assembly includes the steps of installing an outer protective pipe at a marine foundation, which outer protective pipe is realized to extend from a cable hang-off to the seabed; and laying an inner protective pipe through the outer protective pipe to extend from the cable hang-off to a further destination; and wherein the method of installing a transmission cable arrangement further includes a step of loading the transmission cable arrangement into the inner protective pipe towards the further destination. A cable protection assembly and a wind turbine assembly are also provided.

A system comprises a carrier structure configured for carrying a module and a floating support structure configured for supporting the carrier structure. The carrier structure comprises first connection means and the floating support structure comprises second connection means, whereby the first and second connection means are configured for releasable connection and comprise contact surfaces that prevent the carrier structure from rotating about its longitudinal axis when the two structures are connected. A transportation and installation apparatus for the carrier structure is configured for being arranged on a floating vessel.

A buoy (10) comprising a central column (12), an outer frame (14) attached to the central column with buoyancy which may be provided by the outer frame and/or by attached buoyancy units (16). The central column is negatively buoyant and is normally open at one end to allow water to flow in, and create an oscillating water column caused by waves. This water column dampens the effect of wave or other forces on the buoy, thus providing a more stable foundation for a wind powered generator. A further generator may be provided to extract energy from the oscillating water column. The buoy is normally attached to an anchor by one or more tension leg tethers which maintains the buoyancy below the surface of the water which has also be found to increase stability. The anchor may be a modular gravity base anchor.

Provided is an offshore wind turbine installation arrangement, including a lifting assembly realized to hoist a suspended load between a floating installation vessel and a wind turbine assembly, the lifting assembly including a crane supported by the floating installation vessel; a sensor arrangement realized to sense at least a motion of the floating installation vessel; and a controller realized to control elements of the lifting assembly on the basis of the sensed installation vessel motion to adjust the position of the suspended load relative to the wind turbine assembly. Also provided is a method of hoisting a load between a floating installation vessel and an offshore wind turbine assembly.

The offshore jack-up has a hull and a plurality of moveable legs engageable with the seafloor. The offshore jack-up is arranged to move the legs with respect to the hull to position the hull out of the water. The method comprises moving at least a portion of a vessel underneath the hull of the offshore jack-up or within a cut-out of the hull when the hull is positioned out of the water and the legs engage the seafloor. A stabilizing mechanism mounted on the jack-up is engaged against the vessel. The stabilizing mechanism is pushed down on the vessel to increase the buoyant force acting on the vessel.