A buoyant structure contains a hull. The hull has a main deck, a lower inwardly-tapering frustoconical side section that extends from the main deck, a lower generally rounded section extending from the lower inwardly-tapering frustoconical side section, a generally rounded keel, a fin-shaped appendage secured to a lower and an outer portion of an exterior of the keel, and an offloading device slidably connected to an outside surface of the hull configured for rotating around an outer circumference of the hull.

A buoyant structure has a hull having a main deck, a lower inwardly-tapering frustoconical side section that extends from the main deck, a lower generally round section extending from the lower inwardly-tapering frustroconical side section, a keel having an n-polytope shape, a plurality of separate tunnels between columns extending from the keel having an n-polytope shape and a fin-shaped appendage is secured to a lower and an outer portion of the hull. The at least one tunnel contains water at operational depth of the buoyant structure.

A buoyant structure contains a hull having a main deck, a lower inwardly-tapering frustoconical side section that extends from the main deck, a lower ellipsoidal section extending from the lower inwardly-tapering frustroconical side section, a keel having an n-polytope shape, a fin-shaped appendage secured to a lower and an outer portion of the exterior of the keel having the n-polytope shape, and a plurality of columns connected between the keel having the n-polytope shape and the main deck forming one or more tunnels between the plurality of columns.

A buoyant structure having a hull, a main deck, an upper cylindrical side section extending downwardly from the main deck, an upper frustoconical side section, a cylindrical neck, a lower ellipsoidal section that extends from the cylindrical neck, an ellipsoidal keel and a fin-shaped appendage secured to a lower and an outer portion of the exterior of the ellipsoid keel. The upper frustoconical side section located below the upper cylindrical side section and maintained to be above a water line for a transport depth and partially below the water line for an operational depth of the buoyant structure.

A stabilizer that extends from the hull of a watercraft below the waterline when needed is disclosed. The stabilizer produces added drag on the watercraft's counteracting a tendency to change bearing. Stabilization chambers of the stabilizer hold semi contained water to produce an extended drag effect by adding lateral weight due to the water that is semi contained within the chamber during use. The restricted flow of water into and out of the stabilizer and the outer dimensions of the stabilizer provides lateral drag to mute any ambient drift.

The present invention provides a floating offshore wind turbine capable of suppressing yawing of a nacelle caused by a gyro effect which is a cause of adverse influence of power generating efficiency of a wind turbine and endurance of devices thereof. The floating offshore wind turbine 10 includes a rotor 11 which is rotated by wind, a nacelle 13 in which a rotation shaft 12 of the rotor 11 is accommodated, and a tower 15 including a turning seated bearing 14 which supports the nacelle 13 such that the nacelle 13 can turn with respect to a sea surface P to exert a weathercock effect. The tower is provided with yawing suppressing means 16 which suppresses yawing T of the nacelle 13. According to this, it is possible to suppress the yawing T of the nacelle 13 generated by a gyro effect caused by yawing generated in the floating body 31 by waves of the sea surface P.

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. Each column is vertically oriented and the pontoon extends horizontally from the first column to the second column. Each column has a central axis, an upper end, and a lower end. The pontoon includes a first tubular member and a second tubular member positioned laterally adjacent to the first tubular member. 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.

A method for offshore floating petroleum production, storage and offloading comprising receiving hydrocarbons from at least one of an FPSO, production risers, or wellhead on the seabed by a floating hull; processing received hydrocarbons forming hydrocarbon product in the floating hull; storing the hydrocarbon product in the floating hull; and offloading the stored hydrocarbon product. The floating hull contains a hull plan view that is circular and wherein the floating hull has a bottom surface, a top deck surface, at least three connected sections, joined in series and symmetrically configured about a vertical axis with the connected sections extending downwardly from the top deck surface toward the bottom surface. The at least three connected sections contain an upper cylindrical portion, a lower conical section, a cylindrical neck section, and a set of fins secured to the hull configured to provide hydrodynamic performance through linear and quadratic damping.

A structure of a floating, semi-submersible wind turbine platform is provided. The floating wind turbine platform includes three elongate stabilizing columns, each having a top end, a keel end, and an outer shell containing an inner shaft. Each stabilizing column further includes a water entrapment plate at its keel cantilevered in a plane perpendicular to a longitudinal axis of the stabilizing column. The floating wind turbine platform also includes three truss members, each truss member including two horizontal main tubular members and two diagonal tubular members. The truss members connect the stabilizing columns to form a triangular cross-section. An elongate wind turbine tower is disposed over the top end of one of the three stabilizing columns such that the longitudinal axis of the tower is substantially parallel to the longitudinal axis of the stabilizing column.

The present invention provides a floating offshore wind turbine capable of suppressing yawing of a nacelle caused by a gyro effect which is a cause of adverse influence of power generating efficiency of a wind turbine and endurance of devices thereof. The floating offshore wind turbine includes a rotor which is rotated by wind, a nacelle in which a rotation shaft of the rotor is accommodated, and a tower including a turning seated bearing which supports the nacelle such that the nacelle can turn with respect to a sea surface to exert a weathercock effect. The tower is provided with yawing suppressing means which suppresses yawing of the nacelle. According to this, it is possible to suppress the yawing of the nacelle generated by a gyro effect caused by yawing generated in the floating body by waves of the sea surface.