Offshore wind platform with folding radial braces

Abstract

A platform arranged to support a renewable energy system, the platform comprising a central structure (103), wherein the central structure comprises at least three pivot connections (104); and at least three radial arms (102), each radial arm configured to be pivotably connected to a respective pivot connection of the central structure such that each of the at least three radial arms are configured to pivot between a folded configuration and an unfolded configuration.

Description

[0001] Offshore wind platform with folding radial braces

[0002] Field of the Disclosure

[0003] The present disclosure relates to an offshore renewable energy system mounting platform and, in particular, to a platform having pivotable radial arms.

[0004] Background to the Disclosure

[0005] As renewable energy systems, e.g. wind turbines, increase in size, so too shall the size of the structures required to support them. In the case of offshore wind turbines, the footprint of platform structures, e.g. platforms that extend to the sea bed, buoyant platforms, and so on, will be progressively more of a factor as they increase in size to support larger offshore wind turbines, for example, during and after the manufacture of the platform structure. The increasing footprint of each platform structure and number of platform structures being manufactured puts an increasing demand on certain resources, such as the area required for fabrication, assembly, storage and transportation. The increasing demand over time for these limited resources will directly impact the economics of the energy generated.

[0006] The present disclosure seeks to address, at least in part, the drawbacks and disadvantages described above.

[0007] Summary of the Disclosure

[0008] Offshore renewable energy systems, e.g. offshore wind turbines, typically require a platform to support the offshore renewable energy system, such that when deployed the offshore renewable energy system is positioned at an operating depth in a body of water. The platforms typically utilise various fabrication and assembly facilities, ports, trucks, and vessels, between the stages of manufacturing the platform to ultimately deploying of the platform at an installation site, all of which are in demand by other sectors and have limited space available. By reducing, or minimising, the footprint of the platforms, more can be processed in a given area, be that on land, water, or vessel. Smaller footprints and therefore shorter reaches also enable assembly using widely available lifting equipment, rather than specialist lifting equipment having greater reach, to avoid construction bottlenecks. Technology that enables the footprint of a platform to be significantly reduced temporarily will have multiple benefits throughout various phases of the platform from manufacturing to ultimately deploying the platform.

[0009] According to a first aspect of the present disclosure there is provided a platform arranged to support a renewable energy system, the platform comprising: a central structure, wherein the central structure comprises at least three pivot connections; and at least three radial arms, each radial arm configured to be pivotably connected to a respective pivot connection of the central structure such that each of the at least three radial arms are configured to pivot between a folded configuration and an unfolded configuration.

[0010] In some embodiments, the folded configuration of the platform may have a smaller footprint compared to the platform in the unfolded configuration.

[0011] In some embodiments, the platform may be configured to be in the folded configuration during storage and / or transportation, and the platform may be configured to be in the unfolded configuration during deployment and / or energy generation.

[0012] In some embodiments, in the unfolded configuration the platform further comprises: a mooring line arrangement, wherein the mooring line arrangement includes a plurality of mooring lines arranged to tether the platform to a bed of the body of water; and each of the plurality of mooring lines are attached at a first end to an attachment point located proximate to, or at, a distal end of a respective radial arm and attached at a second end to an anchor on the bed of the body of water.

[0013] In some embodiments, each of the at least three radial arms may be configured to pivot about the respective pivot connection to an intermediate configuration between the folded configuration and the unfolded configuration.

[0014] In some embodiments, only a subset of at least one of the radial arms may be in the folded configuration.

[0015] In some embodiments, the central structure may be formed of a buoyant hull, a truss structure, or a combination of both a truss structure and a buoyant hull.

[0016] In some embodiments, the buoyant hull further comprises: a ballasting system, wherein the ballasting system may be arranged to vary a buoyancy and / or draught of the platform. In some embodiments, the platform may further comprise a drive mechanism, wherein the drive mechanism may be detachably connected to the central structure, such that the drive mechanism actuates the folding and unfolding of one or more of the radial arms.

[0017] In some embodiments, a drive mechanism may be detachably connected to an external structure, wherein the drive mechanism actuates the folding and unfolding of one or more of the radial arms.

[0018] In some embodiments, the platform may further comprise at least one temporary line connected at a first end to the drive mechanism and may be connected at a second end to a distal end of a respective radial arm, wherein the temporary line may be removed once the radial arm is in the unfolded configuration.

[0019] In some embodiments, the drive mechanism may be a winch system and / or a reeving system.

[0020] In some embodiments, the platform may further comprise at least three diagonal braces, wherein each diagonal brace may be connected, at a first end, to a first attachment point on the central structure at a predetermined height above the pivot connection, and connected at a second end, wherein the second end is distal to the first end, to a second attachment point on a respective radial arm located between the pivot connection and a distal end of the respective radial arm.

[0021] In some embodiments, the diagonal braces may be rigid structures. In some embodiments, the diagonal braces may be flexible tendons.

[0022] In some embodiments, the platform may further comprise a diagonal brace length adjuster coupled to at least one of the diagonal braces, such that the diagonal brace length adjuster may be configured to adjust the length of a respective diagonal brace.

[0023] In some embodiments, the platform may further comprise a damper, wherein the damper may be positioned between at least one diagonal brace and the central structure.

[0024] In some embodiments, the platform may further comprise a locking mechanism, wherein the locking mechanism may be configured to lock one or more of the radial arms in at least the folded configuration. Thus, the platform of the present disclosure is advantageous as the pivotable, or folding, radial arms enable the platforms footprint to be significantly reduced, or minimised, which is especially advantageous, for example, in assembly yards where storage space is at a premium, due to the number of platforms being manufactured simultaneously as offshore wind farms increase in size and number, on a vessel as a greater number of platforms can be loaded onto a single vessel for transportation for assembly or delivery to the project site, and permit lifting equipment reaches to be significantly reduced, opening up a wider range of available cranes and construction sites.

[0025] The present disclosure is therefore directed to an offshore platform that includes folding radial arms to enable easier onshore and offshore operations to be conducted. The folding radial arm arrangement will be described in the context of a marine, e.g. offshore, renewable energy system but is not limited to only this application and the platform may be used to support any structure or apparatus as required.

[0026] It will be appreciated that any features described herein as being suitable for incorporation into one or more aspects or embodiments of the present disclosure are intended to be generalizable across any and all aspects and embodiments of the present disclosure. Other aspects of the present disclosure can be understood by those skilled in the art in light of the description, the claims, and the drawings of the present disclosure. The foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the claims.

[0027] Detailed Description

[0028] Embodiments of the present invention will now be described by way of example only and with reference to the accompanying drawings, in which:

[0029] Figures 1 A and IB depict a schematic front view of a platform in a folded configuration, according to one or more embodiments of the present disclosure.

[0030] Figures 1C and ID depict a schematic front view of a platform in an unfolded configuration, according to one or more embodiments of the present disclosure.

[0031] Figures 2A and 2B depict a schematic front view of a platform with a drive mechanism, according to one or more embodiments of the present disclosure. Figures 3 A and 3B depict a schematic front view of a platform with rigid diagonal braces, according to one or more embodiments of the present disclosure.

[0032] Figures 4Ato 4F depict a schematic front view of a platform with flexible tendon diagonal braces, according to one or more embodiments of the present disclosure.

[0033] Figures 5 A to 5D depict a schematic front view of a platform attached to a mooring arrangement, according to one or more embodiments of the present disclosure.

[0034] Figure 6A and 6B depict a schematic front view of a platform with flexible tendon diagonal braces held in tension, according to one or more embodiments of the present disclosure.

[0035] Figures 7Ato 7D depict a schematic front view of a platform with a diagonal brace length adjuster, according to one or more embodiments of the present disclosure.

[0036] Figures 8Ato 81 depict a schematic view of a process to deploy a platform, according to one or more embodiments of the present disclosure.

[0037] Figures 9Ato 9D depict a schematic front view of a platform with a wind turbine attached, according to one or more embodiments of the present disclosure.

[0038] With reference to Figures 1 A and IB there is shown an embodiment of a platform 101 with pivotable, or foldable, radial arms 102. The platform comprises a central structure 103, wherein the central structure 103 comprises at least three radial arms 102, wherein each radial arm 102 is pivotably connected by a pivot connection 104, for example, by a hinge or any other suitable mechanism, at a proximal end to the central structure 103. The pivotable connection enables each of the at least three radial arms to pivot, or rotate, about the pivot connection between a folded configuration (shown in Figures 1 A and IB) and an unfolded configuration (shown in Figure 1C and ID), such that in the folded configuration the platform has a smaller footprint compared to the unfolded configuration. The footprint of the platform generally refers to the extent or area of a surface (e.g. the ground, a deck of a vessel, and so on) that the platform occupies or covers. Thus, with one or more of the radial arms positioned in the folded configuration the extent or area that the platform occupies, or covers, is smaller than when all of the radial arms are in an unfolded configuration.

[0039] The central structure 103 of the platform may include an interface 108 (often referred to as a transition piece in the field of wind turbines) at a first end to which an apparatus, e.g. a renewable energy system such as a wind turbine can be attached. The central structure 103 may be formed of a truss structure 105 (shown in Figures IB and ID), or a combination of a truss structure 105 and a buoyant hull 106 (shown in Figures lA and 1C).

[0040] In embodiments where the platform includes a central structure 103 formed substantially of a truss structure 105 the platform extends to, or substantially to, the sea bed, and the platform may include a base connector 107 to engage with a central anchor point on the sea bed.

[0041] In embodiments where the platform includes a central structure 103 formed of both a truss structure 105 and a buoyant hull 106, the platform 101 is a floating platform at an operating depth in the body of water, e.g. a sea, once deployed.

[0042] In embodiments, the truss structure 105 (also referred to as a lattice structure) formed by a plurality of individual connecting members and three or more main chords. The truss structure 105 comprising the connecting members and the main chords may form a series of interconnected geometric shapes, typically a triangular shape, though other geometric shapes may be possible. The connecting members and the main chords are joined at a series of nodes, for example, by “K” nodes, “X” nodes, “L” nodes or any other type of node as required.

[0043] In embodiments, the buoyant hull 106 may be an elongate, or cylindrical, buoyant hull which may include at least one buoyant chamber to provide buoyancy to support the platform and attached apparatus (e.g. a renewable energy system such as a wind turbine) in the body of water at an operating depth in use and once deployed.

[0044] Figures 1 A and IB show the platform 101 with the radial arms 102 in the folded configuration, which is used during storage and / or during transportation of the platform (e.g. on a truck, on a vessel, and so on) in order to reduce, or minimise, the footprint of the platform. In the folded configuration, one or more of the radial arms may be raised such that the distal end of the one or more radial arms are proximate to the central structure 103. In embodiments, the platform may include one or more locking mechanisms to lock the radial arms in the folded configuration to prevent the radial arms from moving during, for example, transport, loading and offloading.

[0045] Figures 1C and ID show the platform 101 with the radial arms 102 in the unfolded configuration, which is used when the platform is deployed (e.g. with or without a renewable energy system attached) and / or operational (e.g. with an operational renewable energy system attached). In the unfolded configuration, all of the radial arms may be lowered to a deployed configuration, wherein the height of the distal ends of the radial arms are below the height of the distal ends of the radial arms in the folded configuration. The position and angle of the distal ends of the radial arms relative to the central structure in the unfolded configuration may be dependent on the site at which the platform is deployed, e.g. shallow water depth, intermediate water depth, deep water depth, or to the sea bed, and may also be dependent on a mooring line arrangement for tethering the platform to the bed of the body of water in which the platform is deployed.

[0046] In embodiments, one or more of the radial arms may be pivoted, or rotated, to an intermediate configuration at a position between the folded configuration and the unfolded configuration. An intermediate configuration may be used to aid assembly of the platform, on land, or during deployment of the platform.

[0047] One or more of the radial arms may be pivoted, or rotated, between the folded configuration and the unfolded configuration using one or more of gravity and the weight of the radial arms, a drive mechanism (e.g. a winch system and / or reeving system), a crane, or by any other suitable mechanism. One or more of the radial arms may be pivoted, or rotated, between the unfolded configuration to the folded configuration using a drive mechanism (e.g. a winch system and / or reeving system), a crane, or by any other suitable mechanism. In the case of a drive mechanism being used to actuate one or more of the radial arms between the folded configuration and the unfolded configuration, the drive mechanism may be temporarily (e.g. detachably) or permanently installed, and may be located on the platform, on a vessel, on a crane, on a quayside structure, or on a manufacturing structure.

[0048] In an example, and with reference to Figures 2A and 2B, a driving mechanism 201, e.g. a winch system, may be detachably (e.g. temporarily, or removably) connected to the uppermost surface of the central structure to actuate the unfolding and / or folding of one or more of the radial arms 102. The winch system 201 may include one or more temporary lines 202 connected at a first end to the winch system 201 and connected at a second end to a connection point on a respective radial arm 102. The connection point may be located at any suitable position on the respective radial arm 102 between the pivot connection 104 at the proximal end of the radial arm and the distal end of the radial arm. In the example, of Figures 2A and 2B, the connection point is located proximate to the distal end of a respective radial arm.

[0049] The winch system 201 enables one or more of the radial arms 102 to be pivoted, or rotated, about the pivot connection 104 to the folded configuration, the unfolded configuration, and any intermediate configuration therebetween.

[0050] In embodiments, once the radial arms have been pivoted to the unfolded configuration, ready for deployment in the body of water at the installation site for the platform, diagonal braces may be used to support and maintain the unfolded configuration of the radial arms. The diagonal braces may be connected at a first end to a first attachment point on the central structure and at a second end, distal to the first end, to a second attachment point on the radial arms. The first attachment point for a given radial arm is located on the central structure, e.g. on a surface of the central structure, substantially above, the pivot connection at a predetermined distance or height, and the second attachment point being located on the given radial arm at a suitable position between the proximal end and the distal end, wherein preferably the second attachment point is located at a predetermined distance from the distal end in the direction of the proximal end of the given radial arm.

[0051] In embodiments, the diagonal braces 301 may include rigid structures (as shown in Figures 3 A and 3B) or may include flexible tendons (as shown in Figures 4Ato 4F).

[0052] With reference to Figures 3 A and 3B, the rigid structures, as diagonal braces, 301 may be connected to the first attachment point 302 on the radial arm 304 and second attachment point 303 on the central structure. To aid the installation of the rigid structure diagonal braces for a given radial arm, the position of the radial arm 304 may be adjusted, for example, using the drive mechanism to compensate for any tolerances in the manufacture of the rigid structure diagonal brace and / or in the given radial arm. The drive mechanism may be used to further compensate for any anchor point installation tolerance and / or mooring line length tolerance.

[0053] With reference to Figures 4A and 4B, the flexible tendons, as diagonal braces, 401 may be connected to a first attachment point 402 on the radial arms 404 and a second attachment point 403 on the central structure to support the radial arms 404 when in the unfolded configuration. With reference to Figures 4C and 4D, to aid the installation of the flexible tendon diagonal braces 401 for a given radial arm 404, the position of the radial arm 404 may be adjusted, for example, using a drive mechanism, to an intermediate configuration (between the folded and unfolded configurations) to enable a slack attachment of the flexible tendon 401, in other words, the flexible tendon is not taut during connection to the first and second attachment points.

[0054] With reference to Figures 4E and 4F, the flexible tendons diagonal braces 401 may be connected to the first attachment point 402 on the radial arm 404 and second attachment point 403 on the central structure prior to being stored or being transported to the deployment site and therefore, the flexible tendons 401 may be in position whilst the platform is in the folded configuration during storage and transportation.

[0055] With reference to Figures 5 A to 5D, once the diagonal braces 501 (flexible tendons are shown in Figures 5A and 5B, whilst rigid structures are shown in Figures 5C and 5D) are supporting and / or maintaining the position of the radial arms 507 in the unfolded configuration, the drive mechanism and any temporary lines associated with the drive mechanism (if used) can be removed. The platform is subsequently lowered into the body of water 502 to an operating depth and attached to a mooring line arrangement that includes a plurality of mooring lines 503. Each mooring line 503 being connected at a first end to an attachment point 504 proximate to, or at, the distal end of a respective radial arm 507, and connected at a second end to an anchor point 505 on a bed 506 (e.g. sea bed) of the body of water 502. In Figures 5A and 5C, a mooring arrangement is shown with the anchor points 505 of the mooring lines being disposed substantially below the point of attachment of the mooring line 503 to the radial arm 102. In Figures 5B and 5D a mooring arrangement is shown with the anchor points 505 of the mooring lines being at an inclined angle to a vertical axis of the central structure and a base piece 508 of the central structure of the platform engages with a central anchor 509 positioned on the sea bed 506. However, as will be appreciated, several different mooring arrangements could be used depending on the deployment site location, e.g. shallow water depth, intermediate water depth, deep water depth, or connected to the sea bed, in order to provide stability to the platform whilst deployed.

[0056] With reference to Figures 6A and 6B, flexible tendons 601 as the diagonal braces may be beneficial as they are typically lighter, or lower in weight, than rigid structures as the diagonal braces. Flexible tendons 601 are enabled by placing, or maintaining, the diagonal braces in a permanent tensioned state 602 when deployed by concentrating the majority of the platform buoyancy B (e.g. the buoyancy force) in the centre of the platform (e.g. from the natural buoyancy of the truss structure and / or the buoyant hull), such that the radial arms are maintained in compression 603, as is an upper section of the central structure 604, the mooring lines are in tension 605, and the radial arms are able to rotate, or pivot, around the pivot connection in pitch.

[0057] With reference to Figures 7Ato 7D, one or more of the diagonal braces 701 (flexible tendons are shown in Figures 7A and 7B whilst rigid structures are shown in Figures 7C and 7D) may include, or be operatively attached to, an inline diagonal brace length adjuster 702 to enable fine tuning of mooring line tension and / or length. The inline diagonal brace length adjuster 702 enables the position of the pivotable radial arms 704 to be adjusted, subsequently enabling the tension in one or more of the mooring lines 703 to be fine-tuned so that they are substantially equal and balanced across the platform. To further aid the fine tuning, the buoyant hull may be partially ballasted to reduce tension in the mooring lines to enable an easier line length adjustment before being de-ballasted to resume normal operation, in embodiments that include the buoyant hull.

[0058] In embodiments, a damper may additionally or alternatively be positioned between the diagonal brace and the central structure, wherein the damper may be included to reduce any structural vibrations and subsequently any fatigue loading of the structure as compared to a welded joint.

[0059] Figures 8 A to 81 depict the process of loading a plurality of platforms 801 onto a vessel 802 through to the deployment of the platform at an operating depth, wherein the diagonal braces are shown as flexible tendons, however, as will be appreciated the diagonal braces may equally be rigid structures. In the example of Figures 8 A to 81, the platform is a floating platform in that the central structure includes both a truss structure and a buoyant hull such that the platform will float at the required operating depth. However, as will be appreciated, the general unloading and deployment process described in Figure 8 A to 81 and the following text can equally apply to a platform having a central structure formed of a truss structure that extends to, or substantially to, the sea bed.

[0060] As shown in Figures 8A and 8B, with the radial arms of each platform 801 in the folded configuration, which reduces, or minimises, the footprint associated with each platform then a higher number of platforms can be loaded onto a vessel 802 for transportation to the deployment site in comparison to the number of platforms that could be loaded onto the same vessel with all of the radial arms in a permanently unfolded configuration. A crane 803 is used that is located on the vessel, however, as will be appreciated the crane may alternatively be located on the quayside 804, to load the platforms 801 onto the vessel 802. However, other arrangements are possible, for example, the platform may be moved, or slid, onto the vessel from the quayside using handling devices on either or both of the vessel and the quayside, wherein the handling devices are operable to move the platform from the quayside and onto the vessel.

[0061] In Figures 8 A and 8B, the platforms 801 are shown with all of the radial arms 805 in the folded configuration, however, as will be appreciated, similar benefits and advantages can be achieved if a subset, or even just one, of the radial arms is in the folded configuration for each platform. In Figures 8 A and 8B, the platforms 801 are loaded widthways onto the vessel 802, however, as will be appreciated, the platforms 801 may alternatively be loaded lengthways onto the vessel 802, which may be advantageous for larger platforms of a longer length.

[0062] As shown in Figures 8C to 8F, at the deployment site a crane 803 situated on a vessel 802 (either the same vessel on which the platforms are transported or a separate vessel alongside) positions a first platform on an upending handling device 806. However, other arrangements are possible, for example, the platform may be moved, or slid, onto the upending handling device that includes the pivoting mechanism using one or more other handling devices that were used to load the platform onto the vessel. In another example, a handling device of each platform may include the pivoting mechanism.

[0063] The upending handling device 806 is operable to manoeuvre the platform from a substantially horizontal orientation across the deck of the vessel to a substantially vertical direction alongside the vessel, which may also be referred to as an upending operation. The upending handling device 806 may therefore include a pivot mechanism having a pivot point 807, and a lifting mechanism 808 to lift the platform around the pivot point 807 of the pivot mechanism. However, as will be appreciated other arrangements are of course possible such as by using the crane to pick up the platform 801 and positions the platform alongside the vessel.

[0064] As shown in Figure 8G, a first radial arm 805 is pivoted, or rotated, about the pivot connection from the folded configuration to the unfolded configuration, wherein the platform is supported and locked to prevent sliding movement by the upending handling device 806 and the crane 803 is utilised to lower the radial arm to the unfolded position. The remaining radial arms 805 may then be lowered to the unfolded position.

[0065] However, as will be appreciated other arrangements are of course possible, for example, the crane may be used to hold the platform to prevent movement, and a drive mechanism can be used to lower the radial arm to the unfolded position. Alternatively, or additionally, one or more of the radial arms may be pivoted, or rotated, about the pivot connection from the folded configuration to the unfolded configuration whilst the platform is held above the surface of the body of water 807, or the radial arms may be pivoted, or rotated, about the pivot connection from the folded configuration to the unfolded configuration progressively as the platform is lowered into the body of water, in both cases under the effects of gravity or by the use of a driving mechanism.

[0066] In embodiments where the platform is a floating platform that includes a buoyant hull, the buoyant hull of the platform may be progressively ballasted as the platform is lowered into the body of water and once the platform is connected to the mooring line arrangement the buoyant hull of the platform can be de-ballasted so that the platforms buoyancy is fully on the permanent mooring system.

[0067] As shown in Figure 8H, the platform 801 may be manoeuvred away from the side of the vessel 802 by the crane 803 to a location that is substantially aligned with one or more anchor points for the mooring line arrangement of the floating platform and / or the central anchor point of the central structure of the platform that extends, or substantially extends, to the sea bed.

[0068] As shown in Figure 81, the mooring line arrangement 809 and a wind turbine 810 may then be installed on the uppermost surface of the central structure of the platform, via the transition piece 811.

[0069] The platform is versatile in that it can be used with several different types of renewable energy systems 901 including, for example, a single turbine with two or three blades, utilising either flexible tendons or rigid structures as the diagonal braces, as shown in Figures 9Ato 9D. However, as will be appreciated other types of renewable energy system can be supported by the platform, for example, a multirotor wind turbine, or any other apparatus as required. The renewable energy system may be mounted on an uppermost surface of the platform and supported by the platform at an operating depth in use, such that at the operating depth the platform is arranged to maintain the renewable energy system above the surface of the body of water. As such, the renewable energy system is protected from the effects of sea water exposure, or from the effects of variable wave forces, on the system.

[0070] In the foregoing embodiments, features described in relation to one embodiment may be combined, in any manner, with features of a different embodiment in order to provide a more efficient and effective platform for storage, transportation, assembly, deployment, and so on.

[0071] Note that, the above description is for illustration only and other embodiments and variations may be envisaged without departing from the scope of the invention as defined by the appended claims.

Claims

Claims1. A platform arranged to support a renewable energy system, the platform comprising: a central structure, wherein the central structure comprises at least three pivot connections; and at least three radial arms, each radial arm configured to be pivotably connected to a respective pivot connection of the central structure such that each of the at least three radial arms are configured to pivot between a folded configuration and an unfolded configuration.

2. The platform of claim 1, in which in the folded configuration the platform has a smaller footprint compared to the platform in the unfolded configuration.

3. The platform of claim 1 or 2, in which the platform is configured to be in the folded configuration during storage and / or transportation, and the platform is configured to be in the unfolded configuration during deployment and / or energy generation.

4. The platform of any one of the preceding claims, in which in the unfolded configuration the platform further comprises: a mooring line arrangement, wherein the mooring line arrangement includes a plurality of mooring lines arranged to tether the platform to a bed of the body of water; and each of the plurality of mooring lines are attached at a first end to an attachment point located proximate to, or at, a distal end of a respective radial arm and attached at a second end to an anchor on the bed of the body of water.

5. The platform of any one of the preceding claims, in which each of the at least three radial arms are configured to pivot about the respective pivot connection to an intermediate configuration between the folded configuration and the unfolded configuration.

6. The platform of any one of the preceding claims, in which only a subset of at least one of the radial arms is in the folded configuration.

7. The platform of any one of the preceding claims, in which the central structure may be formed of a buoyant hull, a truss structure, or a combination of both a truss structure and a buoyant hull.

8. The platform of any one of 7, in which the buoyant hull further comprises: a ballasting system, wherein the ballasting system is arranged to vary a buoyancy and / or draught of the platform.

9. The platform of any one of the preceding claims, further comprising: a drive mechanism, wherein the drive mechanism is detachably connected to the central structure, such that the drive mechanism actuates the folding and unfolding of one or more of the radial arms.

10. The platform of any one of claims 1 to 8, in which a drive mechanism is detachably connected to an external structure, wherein the drive mechanism actuates the folding and unfolding of one or more of the radial arms.

11. The platform of claim 9 or 10, further comprising: at least one temporary line connected at a first end to the drive mechanism and connected at a second end to a distal end of a respective radial arm, wherein the temporary line is removed once the radial arm is in the unfolded configuration.

12. The platform of any one of claims 9 to 11, in which the drive mechanism is a winch system and / or a reeving system.

13. The platform of any one of the preceding claims, further comprising: at least three diagonal braces, wherein each diagonal brace is connected, at a first end, to a first attachment point on the central structure at a predetermined height above the pivot connection, and connected at a second end, wherein the second end is distal to the first end, to a second attachment point on a respective radial arm located between the pivot connection and a distal end of the respective radial arm.

14. The platform of claim 13, in which the diagonal braces are rigid structures.

15. The platform of claim 13, in which the diagonal braces are flexible tendons.

16. The platform of any one of claims 13 to 15, further comprising:a diagonal brace length adjuster coupled to at least one of the diagonal braces, such that the diagonal brace length adjuster is configured to adjust the length of a respective diagonal brace.

17. The platform of any one of claims 13 to 16, further comprising: a damper, wherein the damper is positioned between at least one diagonal brace and the central structure.

18. The platform of any one of the preceding claims, further comprising: a locking mechanism, wherein the locking mechanism is configured to lock one or more of the radial arms in at least the folded configuration.

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