A method of maintaining an offshore power plant. A power generating craft is attached to a tow cable on a floating vessel. The floating vessel is moved to an offshore power generating site. The power generating craft is maintained in an airborne state while the floating vessel is moving to the offshore power generating site. The power generating craft is detached from the tow cable and attached to a first end of a tether line at the offshore power generating site. The second end of the tether line is anchored to an underwater floor. The power generating craft is operated in an airborne state.

A method of generating power. An airborne power generating craft is connected to an anchor using a tether line. The anchor is secured to an underwater floor. Power is generated based on movement of the airborne power generating craft in response to a wind force. The tether line is maintained at a constant length between the airborne power generating craft and the anchor as the airborne power generating craft moves in response to the wind force. The airborne power generating craft is connected to an electrical transmission system through at least part of the tether line. The generated power is transmitted to the electrical transmission system. A condition is sensed in which transmitting power to the electrical transmission system is not desired. The airborne power generating craft is electrically isolated to prevent power from being transmitted from the airborne power generating craft to the electrical transmission system.

A floatable offshore structure, in particular a floatable offshore wind turbine, includes at least one floatable foundation with at least one floating body. The offshore structure further includes at least one anchoring arrangement configured to fix the offshore structure to an underwater ground in an anchoring state of the offshore structure. The anchoring arrangement includes at least one anchor connection between an anchor and the floatable foundation and at least one position stabilization device configured to change the length of the anchor connection between the anchor and the floatable foundation in the anchoring state based on at least one attitude parameter of the offshore structure and at least one attitude set point parameter.

There is provided a renewable power generation farm for fishing work, the farm comprising: a plurality of mutually connected floating ships, wherein each ship is configured to generate an energy using solar and wind power, wherein each ship comprises: a main elongate floating structure; a wind-based energy generation device secured to the main elongate floating structure; a transverse beam extending perpendicularly to a longitudinal direction of the main structure; a longitudinal beam extending in a parallel manner to the longitudinal direction of the main structure; connection beams connecting both opposing ends of the transverse beam and both opposing ends of the longitudinal beam respectively; auxiliary pillars vertically extending through the both ends of the transverse beam and the longitudinal beam respectively; solar-based energy generation devices disposed at top ends of the auxiliary pillars respectively; and auxiliary elongate floating structures disposed at bottom ends of the auxiliary pillars passing through the ends of the transverse beam.

The invention relates to a floating platform for harnessing wind energy, comprising a tower (1) with a wind turbine (2), and two horizontal, identical cylindrical floating elements (3) parallel to the main longitudinal axis of alignment, the tower and the floating elements being interconnected by bar structures (5). The floating elements are joined to a stabilising element (4) which is situated directly beneath the floating elements (3), said stabilising element comprising two substantially rectangular first concrete slabs (4a), which are solid or more lightweight, with a ribbed structure, arranged perpendicularly to the axes of the floaters and joined to said floaters by means of auxiliary structures.

A method for controlling an inclination of a floating wind turbine platform to optimize power production, or to reduce loads on the turbine, tower, and platform, or both, includes receiving data associated with the inclination of the floating wind turbine platform and wind speed and direction data. An angle of difference between the turbine blade plane and the wind direction is determined, where the angle of difference has a vertical component. A platform ballast system is then caused to distribute ballast to reduce the vertical component to a target angle chosen to optimize power production, or reduce turbine, tower, and platform loads, or both.

The invention relates to the embodiment, by means of a pre-stressed concrete layer, on floating structures for supporting wind turbines, of the transition zone between the tower, of a lesser diameter, and the concrete float, of a greater diameter, whether the tower is made of metal or concrete. Said layer of revolution has the optimum geometry for the correct transmission of forces between the two parts, the tower and the float, with a reduced thickness and without the need for external rigidifying and reinforcing elements on the surfaces thereof, which would increase the weight and the cost of the structure.

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 relates to methods and apparatus for operating a safety system in a floating wind turbine. The floating wind turbine comprises one or more sensors 202, 203, and receives a fore-aft inclination signal from the sensor 202, wherein the fore-aft inclination signal indicates an inclination of said floating wind turbine in a fore-aft direction. A side-to-side inclination signal is also received from the sensor 203, wherein the side-to-side inclination signal indicates an inclination of said floating wind turbine in a side-to-side direction. An operational parameter of the floating wind turbine is altered based on either or both of said fore-aft inclination signal and said side-to-side inclination signal.

An offshore floating support apparatus includes an underwater base, an anchor unit and a plurality of supporting units. The anchor unit is connected to the underwater base and is adapted to be attached to a water bed. The supporting units are connected to and surround the underwater base. Each of the supporting units has a support member that defines a receiving space for receiving water therein and that has a valve component operable to establish fluid communication between the receiving space and external environment for adjusting quantity of water received in the support member.