Provided is a semi-submersible floating foundation for supporting a wind power generation system. In one embodiment, the floating foundation includes a plurality of outer buoyant columns equidistantly spaced around a center buoyant column that are connected by buoyant structural pontoons. The center buoyant column supports a horizontal axis wind turbine (HAWT) or a vertical axis wind turbine (VAWT) energy system. The floating foundation includes motion attenuating extensions with or without porosity attached to the sides of the pontoons. Deepwater station-keeping system of the floating foundation includes a plurality of disconnectable and reconnectable taut or semi-taut mooring lines coupling one or more outer buoyant columns to seabed anchors. Inter-array power cable between a plurality of floating foundations may be free hanging or supported by buoyant modules. Export power cable from a floating foundation to seabed toward shore may be free hanging or supported by buoyant modules.

A method for constructing a hull of an offshore structure includes (a) welding a plurality of plates together to form a plate assembly. The method also includes (b) passing the plate assembly through a rolling machine with the plate assembly in a vertical orientation. In addition, the method includes (c) bending the plate assembly into a cylinder during (b). The cylinder includes a pair of circumferentially adjacent free ends. Further, the method includes (d) welding the free ends of the cylinder together after (c) to form a cylindrical external wall.

A highly safe large floating structure, and a basic module of a very large floating structure, includes multiple lower floating bodies, an upper structure, and intermediate connection structures. The multiple lower floating bodies include multiple distributed strip-shaped floating bodies. The floating bodies are spaced from each other by a certain distance. The sum of the displacement volumes of the floating bodies is greater than the displacement volume when the floating structure as a whole is fully loaded. The intermediate connection structures include at least multiple connection structures in a first direction, the first direction intersecting the horizontal plane. A connection structure in the first direction corresponds to a single strip-shaped floating body connected to three or more spaced structures. The cross-section width of each intermediate connection structure in the horizontal direction is less than the width of the corresponding strip-shaped floating body.

A semi-submersible wind power platform includes a tower and a plurality of arms for stabilizing the tower, each arm having a float experiencing an anchoring force. Each arm consists of two elongated elements forming with part of the tower a triangle, and at least one of the elongated elements includes a catenary element.

Provided is a floating foundation for supporting a wind power generation system including a stabilized power cable. In one embodiment, the floating foundation includes a column extending upwardly and couplable at a top end thereof to a base of the wind turbine, at least one power cable for exporting power generated from the wind turbine to another floating foundation or to an offshore/onshore station, and a plurality of buoyancy modules disposed along the at least one power cable. Power cables between a plurality of floating foundations and/or power station may be supported by buoyant modules such that the power cable is located in an optimal submergence range of the water body in which the floating foundations are deployed.

A mooring system for mooring a floating platform having a plurality of stabilizing arms with floats, the mooring system including an anchoring system containing a plurality of anchors and anchoring cables for anchoring the mooring system in deep sea. The center part of the mooring system includes a mooring unit containing a plurality of mooring elements and positioning wires, where each mooring element is connected to an adjacent mooring element with a positioning wire and to an anchor.

A floating platform for high-power wind turbines, comprising a concrete substructure, said concrete substructure forming the base of the platform, which remains semi-submerged in the operating position, and consisting of a square lower slab on which a series of beams and five hollow reinforced concrete cylinders are constructed, distributed at the corners and the center of said lower slab; a metal superstructure supported on the concrete substructure and forming the base for connection with the wind turbine tower, said tower being coupled at the center thereof; and metal covers covering each of the cylinders, on which the metal superstructure is supported and to which vertical pillars are secured, linked together by beams, which join at the central pillar by an element whereon the base of the wind turbine tower is secured.

The invention relates to a floating structure, comprising a plurality of interconnected frames and a plurality of buoyant members supporting the structure, wherein the frames are substantially triangular in planform. Adjacent triangular frames may be movably connected, in particular pivotably connected. The triangular frames may comprise right-angle triangles, isosceles triangles or equilateral triangles. The floating structure may support an installation, like e.g. a solar farm. The invention also relates to a triangular frame for use in such a floating structure.

A floating device for supporting an offshore wind turbine, comprising a central floating pillar for fixedly receiving a tower of the wind turbine, at least three peripheral floaters, and one leg per floater, each leg extending in a longitudinal direction that runs radially in relation to the central pillar; each leg has a proximal end that is secured to the central pillar, and a distal end that is secured to the floater; the legs include an outer tubular element, which extends in the longitudinal direction of the leg and has a curved cross-section perpendicularly to the longitudinal direction, and an inner tubular element, which extends in the longitudinal direction of the leg and has a polygonal cross-section perpendicularly to the longitudinal direction, the polygonal cross-section being inscribed in the curved cross-section. The invention also relates to a floating wind turbine unit comprising the device and a wind turbine.

A floating offshore structure includes a buoyant hull including a first column, a second column, and a pontoon coupled to the first column and the second column. The pontoon extends horizontally from the first column to the second column. The pontoon includes a first tubular member, a second tubular member positioned laterally adjacent to the first tubular member, a first edge plate extending horizontally from the first tubular member, and a second edge plate extending horizontally from the second tubular member. The first tubular member and the second tubular member are disposed between the first edge plate and the second edge plate. Each tubular member has a central axis, a first end coupled to the lower end of the first column, and a second end coupled to the lower end of the second column. The longitudinal axis of the first tubular member and the longitudinal axis of the second tubular member are disposed in a common horizontal plane.