Anchor point formation system for offshore wind turbine floats and installation method

Description

1 / 10 SYSTEM FOR FORMING AN ANCHORING POINT FOR OFFSHORE WIND TURBINE FLOATS AND INSTALLATION METHOD Technical field

[0001] The present invention relates to the general field of floats for offshore wind turbines. More specifically, it relates to anchoring systems connected to the seabed, allowing such floats to be held in place. State of the art

[0002] The purpose of an offshore wind turbine is to use wind energy to produce electricity using a turbine and an electric generator. There are two main types of offshore wind turbines: fixed wind turbines, which are installed on the seabed (at shallow depths, typically less than 50 m), and floating wind turbines, which have the advantage of being able to be built on land and installed in areas where the seabed is typically deeper than 50 m.

[0003] Floating wind turbines typically comprise a turbine that is generally formed by a motor with a plurality of rotating blades with a horizontal axis and an electric generator coupled to the motor, the motor and generator being fixed to an upper end of a vertical mast (or tower), the lower end of which is mounted on a float.

[0004] There are three main categories of floats for offshore wind turbines: semi-submersible floats, submerged floats with tensioned cables (or TLP platform for TensionLeg Platform) and SPAR floats (Single Point Anchor Reservoir).

[0005] Currently, semi-submersible floats and SPARs (Single Point Anchor Reservoirs) are the most commonly used float models. They consist of a steel or concrete structure, generally... Petition 870250086201, dated 09 / 24 / 2025, page 10 / 42 2 / 10 in the form of a tripod with three interconnected columns (for the semi-submersible float type) or a single central column (for the SPAR float type). The structure of these floats comprises a submerged part and mooring lines that are not tensioned, but which must still support the drift of the assembly.

[0006] There are several technologies for manufacturing floating mooring lines for offshore wind turbines: drag anchors (e.g., Delta Flipper or Stevpris anchors), which are particularly suitable for anchoring catenary lines in sedimentary soils (clayey, sandy to clayey-sandy); mooring piles, which involve driving a metal tube, either by driving it into the seabed consisting of sandy-clayey to silty-clayey soil, or by drilling into a rocky bottom; or by suction in a soft silty-clayey to clayey bottom; and the gravity anchor, which is placed on the seabed consisting of sedimentary soil (clayey, sandy to clayey-sandy) and / or rocky soil and serves as a fixed point for the mooring lines, supporting them due to its weight.

[0007] In floating offshore wind farm development projects, the heterogeneity of seabed soil conditions, where the soil type changes rapidly in both nature and thickness, can present risks to the anchoring system and its installation, generating concerns among the developers of these projects.

[0008] For example, shallow or subsurface rocky soils and / or soils with thin layers of sediment over weathered rocks do not allow the installation of drag anchoring systems. However, this type of soil also presents problems if drilling and grout injection or pile installation is chosen.

[0009] In general, these risks are linked to the geotechnical profile of Petition 870250086201, dated 09 / 24 / 2025, page 11 / 42 3 / 10 soil and seabed conditions (irregularities, seabed singularities, such as slopes, inclines, depressions, incisions, boulders, etc.) which, if encountered, generate concerns that may compromise the anchoring system and its installation. Description of the invention

[0010] One objective of the invention is to propose a system that forms a simple-to-manufacture and use gravitational anchoring point and that, once installed on the seabed, resists anchoring forces, mainly due to its own weight.

[0011] According to the invention, this objective is achieved by a system that forms an anchoring point for offshore wind turbine floats, comprising at least one cellular containment casing with an open bottom and an open top, the containment casing being at least partially filled with a solid granular material capable of resisting shear with the seabed on which the containment casing is intended to rest, further comprising at least one eyelet for attaching a mooring line from the float.

[0012] The system that forms an anchoring point according to the invention is characterized by comprising a containment casing that is lightweight due to its structure, but which is filled with a solid granular material to make it heavier when placed on the seabed. The result is an assembly composed of the containment casing and its solid granular material – known as a gravity anchoring point – which is low cost to manufacture and simpler to use, particularly compared with pile anchoring systems.

[0013] The containment enclosure may be cylindrical with a plurality of radial walls. In this case, the radial walls of the containment enclosure may be connected to each other along a symmetry axis. Petition 870250086201, dated 09 / 24 / 2025, page 12 / 42 4 / 10 of the containment enclosure. Alternatively, the radial walls of the containment enclosure can be connected to an inner cylinder centered on an axis of symmetry of the containment enclosure.

[0014] The containment enclosure may have a polygonal shape with a plurality of radial walls. In this case, these radial walls may be connected to each other along an axis of symmetry of the containment enclosure. Alternatively, the radial walls of the containment enclosure may be connected to an internal polygon centered on an axis of symmetry of the containment enclosure.

[0015] The system may comprise a plurality of identical containment enclosures connected to each other.

[0016] In this case, the containment enclosures of the anchoring system may be stacked on top of each other and / or placed side by side.

[0017] The containment enclosure may be composed of a plurality of interconnected containment enclosure sectors.

[0018] Preferably, a lower surface of the containment casing is corrugated or sawtooth-shaped to increase the coefficient of friction between the containment casing and the seabed material.

[0019] Even more preferably, the system also comprises a solid ballast material disposed around the containment enclosure.

[0020] An inner surface of the containment enclosure may be roughened to limit the risk of displacement of the system.

[0021] Another object of the invention is a method of installing a system as defined above, comprising transporting the system that forms an anchor point on a barge to an installation area on a barge and then depositing it on the seabed. Petition 870250086201, dated 09 / 24 / 2025, page 13 / 42 5 / 10

[0022] Alternatively, the method of installing a system as defined above may comprise towing at sea to a system installation area that forms an anchor point, the latter being fitted with temporary flotation devices, and then depositing the system on the seabed, emptying the flotation devices and / or filling them with seawater. Brief description of the drawings

[0023] [Fig. 1] Figure 1 is a cross-sectional view of an in situ system that forms an anchor point according to the invention.

[0024] [Fig. 2] Figure 2 shows a perspective view of the system shown in Figure 1.

[0025] [Fig. 3A] and [Fig. 3B] Figures 3A and 3B show a perspective view of a system according to an alternative embodiment of the invention.

[0026] [Fig. 4A] and [Fig. 4B] Figures 4A and 4B show polygonal systems according to other alternative embodiments of the invention.

[0027] [Fig. 5A] and [Fig. 5B] Figures 5A and 5B show polygonal systems according to other alternative embodiments of the invention.

[0028] [Fig. 6A] and [Fig. 6B] Figures 6A and 6B show cylindrical systems according to other alternative embodiments of the invention.

[0029] [Fig. 7A] and [Fig. 7B] Figures 7A and 7B show a system according to other alternative embodiments of the invention.

[0030] [Fig. 8A] and [Fig. [8B] Figures 8A and 8B show a system according to other alternative embodiments of the invention.

[0031] [Fig. 9] Figure 9 is an in situ cross-sectional view Petition 870250086201, dated 09 / 24 / 2025, page 14 / 42 6 / 10 of a system according to the invention, surrounded by solid granular material.

[0032] [Fig. 10] Figure 10 is an in situ cross-sectional view of a system according to another alternative embodiment of the invention. Description of the achievements

[0033] The invention relates to a system that forms a gravitational anchoring point that has the function of holding in place offshore wind turbine floats (e.g., semi-submersible or SPAR type floats) due to their large mass, which remains in place on the seabed and / or due to the friction generated on the seabed.

[0034] Figure 1 shows an example of such a system 2 that forms an in situ gravitational anchor point, i.e., placed on the seabed 4.

[0035] According to the invention, this system 2 comprises at least one cellular containment enclosure 6, having an open bottom 8 and an open top 10. The containment enclosure 6 can be made of prestressed or non-prestressed concrete and / or steel.

[0036] Furthermore, this containment casing 6 is at least partially filled with a solid granular material 12, capable of resisting shear with the seabed 4 on which the containment casing is intended to rest. The solid granular material 12 may consist of a large-sized rocky granular material.

[0037] The containment attachment 6 also comprises at least one eyelet 14 for attaching a floating mooring line 16.

[0038] System 2, according to the invention, therefore consists of a shear and meeting resistance system combined with the containment adhesion 6 with the volume of solid granular material 12. Petition 870250086201, dated 09 / 24 / 2025, page 15 / 42 7 / 10

[0039] It should be noted that the volume of selected solid granular material (surface area and height) is defined according to the required anchoring strength.

[0040] It should also be noted that the volume of solid granular material 12 used by the system, according to the invention, is located inside, outside and below the containment enclosure 6.

[0041] It should also be noted that the containment enclosure of the system, according to the invention, can take different forms.

[0042] Thus, in the embodiment shown in Figure 2, the containment enclosure 6-1 of the system has a cylindrical shape with a plurality of radial walls 18 that are connected to each other on an axis of symmetry XX of the containment enclosure.

[0043] More specifically, in the embodiment shown in the Figure 2, there are six radial walls 18 that are regularly spaced angularly from each other.

[0044] In the embodiment shown in Figures 3A and 3B, the containment enclosure 6-2 of the system is cylindrical with a plurality of radial walls 18 that are connected to an inner cylinder 20 centered on an axis of symmetry XX of the containment enclosure.

[0045] In the embodiment shown in Figures 4A and 4B, the containment enclosures 6-3 and 6-4 of the anchor point system each have the shape of a polygon (here a hexagon) with a plurality of radial walls 22.

[0046] In the embodiment shown in Figure 4A, these radial walls 22 are connected to an internal polygon (here a hexagon) centered on an axis of symmetry XX of the containment envelope 6-3.

[0047] In the embodiment shown in Figure 4B, these radial walls 22 are joined on an axis of symmetry XX of the containment enclosure 6-4.

[0048] Furthermore, whatever the geometric shape of the enclosure Petition 870250086201, dated 09 / 24 / 2025, page 16 / 42 8 / 10 containment profit, the system according to the invention may comprise a plurality of identical containment enclosures connected to each other.

[0049] Thus, in the embodiment shown in Figure 5A, the system 2a comprises two containment enclosures 6-3, as described in connection with Figure 4A, the two containment enclosures being stacked one on top of the other along their axis of symmetry XX.

[0050] Similarly, in the embodiment shown in Figure 5B, system 2b comprises six containment enclosures 6-3, as described in connection with Figure 4A. Furthermore, the containment enclosures are stacked two by two along their axis of symmetry XX, and the three pairs of containment enclosures formed in this manner are placed side by side.

[0051] In the embodiment shown in Figure 6A, system 2c comprises three containment enclosures 6-2, as described in connection with Figure 3A, the three containment enclosures being stacked one on top of the other along their axis of symmetry XX.

[0052] In the embodiment shown in Figure 6B, the 2d system comprises nine containment shells, each formed by a 6-2 containment shell, as described in connection with Figure 3A. Here, the containment shells are stacked three by three along their XX axis of symmetry, and the three trios of containment shells thus formed are placed side by side.

[0053] In the embodiment shown in Figures 7A and 7B, the containment enclosure is composed of a plurality of interconnected containment enclosure sectors.

[0054] In the example shown in Figure 7A, the 6-5 containment enclosure is cylindrical and consists of five identical angled sectors 26. In the example shown in Figure 7B, the 6-6 containment enclosure is star-shaped and consists of a set of four angled sectors. Petition 870250086201, dated 09 / 24 / 2025, page 17 / 42 9 / 10 identical households 28.

[0055] According to an advantageous arrangement illustrated, in particular, in Figure 8A, the lower surface 30 of the containment casing 6-7 of the system that forms an anchor point has saw teeth to increase the coefficient of friction between the containment casing and the seabed material.

[0056] Again, to increase the coefficient of friction between the containment casing and the seabed material, the lower surface 32 of the containment casing 6-8 of the system can alternatively be corrugated (see Figure 8B).

[0057] In a further advantageous arrangement illustrated in Figure 9, the system forming an anchor point further comprises a solid granular material 38 that is arranged around the containment enclosure 6. This solid granular material 38 may be the same used to fill (at least partially) the containment enclosure of the system.

[0058] The presence of solid granular material 38 around the containment separation has the advantage of increasing the lateral resistance of the vertical cellular structure to subhorizontal tension.

[0059] According to another advantageous arrangement illustrated by figure 10, the containment casing 6 of the system that forms an anchor point comprises, on its inner surface 40, a roughness that can limit the risk of the system detaching from the solid granular material 12.

[0060] One method for installing a system that forms an anchor point, as defined above, may be as follows. The initial step involves transporting the system on a barge to an installation area. The system is then deposited on the seabed.

[0061] Another method for installing a system that forms an anchor point, as defined above, may be the following. The step Petition 870250086201, dated 09 / 24 / 2025, page 18 / 42 The initial 10 / 10 phase involves towing the system at sea to its installation area. For this purpose, the system will be equipped with temporary flotation devices, such as buoys.

[0062] Once it arrives at the installation area, the system, and more specifically its containment float, is deposited on the seabed by deflating and / or filling the float devices with seawater, and then the solid granular material is deposited to at least partially fill the interior of the casing. Petition 870250086201, dated 09 / 24 / 2025, page 19 / 42

Claims

1 / 3 CLAIMS 1. System (2) for forming an anchor point for offshore wind turbine floats, characterized in that it comprises at least one cellular containment enclosure (6; 6-1 to 6-9) having an open bottom (8) and an open top (10), the containment enclosure being at least partially filled with a solid granular material (12) capable of withstanding shear with the seabed (4) on which the containment enclosure is to rest, the containment enclosure further comprising at least one eyelet (14) for attaching a mooring line (16) of the float.

2. System according to claim 1, characterized in that the containment enclosure (6-1, 6-2) is cylindrical, with a plurality of radial walls (18).

3. System according to claim 2, characterized in that the radial walls (18) of the containment enclosure are connected to each other on an axis of symmetry (XX) of the containment enclosure (6-1).

4. System according to claim 2, characterized in that the radial walls (18) of the containment enclosure are connected to an inner cylinder (20) centered on an axis of symmetry (XX) of the containment enclosure (6-2).

5. System according to claim 1, characterized in that the containment enclosure (6-3, 6-4) is polygonal in shape with a plurality of radial walls (22).

6. System according to claim 5, characterized in that the radial walls (12) of the containment enclosure are connected to each other on an axis of symmetry (XX) of the containment enclosure (6-4).

7. System, according to claim 5, characterized in that the radial walls (22) of the containment enclosure are connected to an internal polygon centered on an axis of symmetry (XX) of the containment enclosure (6-3).

8. A system according to any one of claims 1 to 7, characterized in that it comprises a plurality of identical containment compartments connected to each other.

9. System according to claim 8, characterized in that the containment casings are stacked one on top of the other.

10. System according to claim 8 or 9, characterized in that the containment enclosures are placed side by side.

11. System according to any one of claims 1 to 10, characterized in that the containment enclosure (6-5) is composed of the assembly of a plurality of enclosure sectors (26) assembled together.

12. System, according to any one of claims 1 to 11, characterized in that a lower surface (30, 32) of the containment casing (6-7, 6-8) is corrugated or sawtooth shaped.

13. System, according to any one of claims 1 to 12, characterized in that it further comprises a solid granular material (38) arranged around the containment casing (6).

14. System, according to any one of claims 1 to 13, characterized in that an inner surface (40) of the containment enclosure is provided with roughness to limit the risk of displacement of the system.

15. Method for installing a system as defined in any of claims 1 to 14, characterized in that it comprises transporting the system, forming an anchor point, on a barge to an installation area and then depositing it on the seabed.

16. A method for installing a system, as defined in any one of claims 1 to 14, characterized by comprising towing the system at sea to an installation area that forms an anchor point, the latter being equipped with temporary flotation devices, and the subsequent deposition of the system on the seabed by emptying the flotation devices and / or filling them with seawater. Petition 870250086201, dated 24 / 09 / 2025, p. 22 / 42

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