Wave energy conversion apparatus and methods of use thereof

Abstract

Embodiment of a wave energy conversion (WEC) apparatus are disclosed. In one embodiment, a WEC apparatus (10) comprises an outer member (14) and an inner member (16). At least one of the outer member (14) and inner member (16) is configured to move in response to an incident wave regime. In use, relative motion between the outer member (14) and the inner member (16) is used to generate electrical power.

Description

[0001] Wave energy conversion apparatus and methods of use thereof

[0002] Technical Field

[0003] The present disclosure relates to a wave energy conversion apparatus, related wave energy conversion system, and related methods of use thereof. In particular, the present disclosure relates to the use of a wave energy conversion apparatus comprising first and second vertically extending members, wherein the relative motion between the members is used to generate power. The present disclosure also relates to a platform (or floating support structure) or system comprising a plurality of wave energy conversion apparatuses.

[0004] Related application

[0005] The present applications claims the benefit of Australian provisional patent application AU 2023902993 filed on 15 September 2023, the entire content of which is incorporated herein in its entirety.

[0006] Background

[0007] Around 80% of the worlds primary energy supply comes from fossil fuels. However, the use of fossil fuels results in local air pollution and the emission of CO2 and other greenhouse gases. In recent decades there has been an increase in demand for renewable energy sources such as solar, wind, and wave power.

[0008] The use of wave energy has long been considered a potential source of renewable energy, and a number of known wave energy conversion devices exist. Typically, wave energy conversion devices can be categorised as either floating or fixed systems.

[0009] Two of the more advanced wave energy technologies developed to date include fixed systems such as the submerged pressure differential system described in U.S. Patent Application Publication No. 20120102938, and floating systems such as the point absorber system described in PCT Patent Application Publication No.

[0010] WQ201 1062576.

[0011] There are known problems associated with both fixed and floating systems of the current art. Fixed systems are fixed to the seabed and require expensive foundation systems, and as the systems are predominantly submerged many of the component parts require expensive sealing systems and have limited accessibility for maintenance. Floating systems can solve the issue of foundation complexity but typically have been found to have low levels of survivability in storm events and are generally of a scale insufficient for commercial viability and utility scale power production.

[0012] Accordingly, it is therefore against this general background that the principles described herein have been developed, and which seek to overcome or ameliorate, at least in part, the aforementioned disadvantages of previous or existing technologies.

[0013] Summary

[0014] In accordance with a first aspect, an embodiment provides a wave energy conversion (WEC) apparatus comprising an outer member and an inner member, wherein at least one of the outer member and inner member is configured to move in response to an incident wave regime, and wherein in use, relative motion between the outer member, and the inner member is used to generate electrical power.

[0015] In a second aspect, an embodiment provides a floating wave energy conversion (WEC) apparatus comprising: an outer member and an inner member arranged in nested or sleeved relation, wherein at least one of the outer member or the inner member is configured to move in response to an incident wave regime, a power take-off (PTO) module operably coupling the inner member and the outer member, at least a portion of the PTO module being accommodated, hosted or housed substantially in one of the outer or the inner members, wherein, in use, relative motion between the outer and the inner members is converted into electrical power.

[0016] In a third aspect, an embodiment provides a floating wave energy conversion (WEC) apparatus comprising: an outer member and an inner member arranged in nested or sleeved relation, wherein at least one of the outer member or inner member is configured to move in response to an incident wave regime, a power take-off (PTO) module operably coupling the inner member and the outer member, the PTO module comprising at least a first portion and at least a second portion that are accommodated, hosted or housed substantially in one of the outer or inner members, with one of the at least one first or second portions being coupled or anchored to or with the other of the outer or inner members, wherein, in use, relative motion between the at least one first portion and the at least one second portion is used to generate electrical power.

[0017] Embodiments of the above-described aspects, and those described below, may comprise, either individually or in combination, any of the following features. It will be appreciated that various operable features may be enabled as steps, actions, or events as part of other aspects of the principles described herein that provide methods for generating energy.

[0018] In one embodiment, the outer member of the WEC apparatus is a vertically extending member having an opening extending vertically therethrough, and the inner member is a vertically extending member provided in the vertical opening of the outer member.

[0019] In another embodiment, the outer member is a vertically extending cylindrical member having an opening extending vertically therethrough, and the inner member is a vertically extending enclosed cylindrical member.

[0020] In an embodiment, the outer and inner members are arranged concentric relative to each other about an axis, the axis being aligned substantially with the vertical plane.

[0021] In an embodiment, a cross-sectional shape of the outer member or inner member is generally symmetrical about a respective axis (eg. axis of symmetry) of the relevant member. The use of a generally symmetrical device, shape or profile may be advantageous as the operation of the device, shape or profile (and consequentially, for example, the operation of the WEC apparatus) does not depend on wave direction and / or does not require additional complexity related to a need to incorporate a weather vaning or heading control system. Other embodiments of the outer or inner members possessing symmetry about the vertical plane (eg. an oval cross-sectional shape / profile) may find use with embodiments of the WEC apparatus.

[0022] In a further embodiment, the outer member is operably connected to or with the inner member by a guide means.

[0023] In another embodiment, the outer member is slidably or retained to or with the inner member by the guide means. In various implementations of use, the guide means may be configured so as to allow generally vertically aligned movement of the inner member and the outer member relative to each other.

[0024] In another embodiment, the guide means is configured so as to limit yaw (eg. relative rotational between the outer and inner members about the axis) and / or axial movement of the outer member and the inner member relative to each other. It will be appreciated by the skilled reader that the guide means can be any means / arrangement which operates to allow or enable generally vertically aligned movement of the outer member and inner member relative to each other. Examples of suitable guide means include, but are not limited to, suitable keyway arrangements, track systems, static guide systems, bearing systems (eg. water bearing arrangements), roller systems, or prismatic coupling arrangements.

[0025] In an embodiment, the outer member is operably connected or slidably retained to or with the inner member by a guide means, the guide means being configured to (i) enable vertical movement of the inner member and outer member with respect to each other, and (ii) to limit yaw, twisting or rotational movement of the inner member and outer member with respect to each other.

[0026] In an embodiment, the guide means is further configured to limit the axial movement of the inner member and outer member with respect to each other. In such, embodiments, the guide means may comprise an end stop arrangement.

[0027] In an embodiment, a smallest diameter of an inner surface of the outer member is greater than a largest diameter of an outer surface of the inner member.

[0028] In an embodiment, the WEC apparatus is ballasted. In some embodiments, ballasting may not be required, for example, due to efficiency in design of hydrostatic stability of one or both of the outer and inner members, and / or other components of the WEC apparatus.

[0029] In one embodiment, at least one of or each of the outer member and inner member comprises a fixed ballast means. In one form, the fixed ballast means is provided towards a bottom or base / foot region of the relevant of the outer or inner member.

[0030] In an embodiment, the fixed ballast means is provided with either the outer member or the inner member only.

[0031] In another embodiment, the outer member and the inner member each comprise a fixed ballast means provided towards a bottom or base / foot region of the respective member. In one form, the fixed ballast means is designed to be a non-removable ballast. Suitable materials for use as the fixed ballast means include, for example (non-exhaustively), high density materials such as steel, Iron, concrete, and lead. The skilled person would readily identify or be aware of suitable ballasting materials for use as the fixed ballast means.

[0032] In some embodiments, the fixed ballast means may comprise more than one ballasting means. For example, the fixed ballast means may comprise a first ballast element comprising a high density material attached to or housed within a base or foot region of the relevant vertically extending member, and a second ballast element, such as for example water, may be provided in a fixed ballast tank or chamber. The relevant vertically extending member may be configured, in use, to receive the second ballast element (eg. using a suitable pumping means, such as for example, a bilge or submersible pump) once the WEC apparatus has been provided in the desired geographical location. The weight of the fixed ballast means may be predetermined so as to ensure the stability of the WEC apparatus when in use at a given geographical location and / or sea environment. A number of considerations influence the required ballast required by the WEC. Such factors include, but are not limited to: targeting incident wave conditions to optimize power production of the WEC apparatus; giving consideration to a predetermined or desired Response Amplitude Operator (RAO) of the WEC apparatus, maintaining a positive metacentric height, maintaining a desired freeboard (or draft), such that waves do not rise past a predetermined point at the top of the outer and inner members; maintaining a minimum distance from the bottom or base / foot of the WEC apparatus to the seabed; maintaining integrity of the WEC apparatus during storm events (i.e. maximizing storm survivability); limiting vertical movement of the WEC apparatus during maintenance or repair events; and, maintaining integrity of a dynamic power cable used for providing grid quality electricity product to an electricity distribution means, ie. a grid. In certain instances, fixed ballast calculation may be based on a combination of one or more of the above factors.

[0033] In an embodiment, one or each of the outer and inner members further comprise a variable ballast means. The variable ballast means may be configured so as to be adjustable, such that the depth or draft of the individual outer / inner members can be adjusted or varied. Generally, speaking, the draft of the inner and / or outer members is considered to be related to the hydrodynamic performance and motions of the inner and / or outer members. The size and ballasting requirements of the outer and inner members of the WEC apparatus may be designed according to the requirements of the geographical location of intended operation of the WEC apparatus. In this manner, the range of depths or drafts available by adjusting the variable ballast means may be a function of, for example, a range of target wave periods.

[0034] In one embodiment, a first pump (eg. a submersible or bilge pump) is provided inside of a respective ballast tank or chamber of the variable ballast means and configured operable for removing water held inside the ballast tank or chamber to external environs. In an embodiment, a second pump is provided external of the ballast tank or chamber of the variable ballast means and configured operable for pumping water from the external environs into the ballast tank or chamber.

[0035] In an embodiment, the amount of variable ballast means required may be calculated such that, in use, one or each of the outer and inner member has a predetermined resonance in an incident wave regime. In one embodiment, at least one of the outer member and inner member resonates in an incident wave regime. In another embodiment, the variable ballast means of the outer member and inner member are adjusted or adjustable such that the outer member and inner member each resonate at different wave frequencies or resonate out-of-phase in the same wave frequency.

[0036] In certain embodiments, the variable ballast means of the outer member and / or inner member are adjusted or adjustable such that the outer member and inner member each resonate at different wave frequencies (have different resonant frequency) and also such that the vertical motion of the outer member is out of phase with the vertical motion of the inner member (phase relationship).

[0037] In an embodiment, the variable ballast means comprises at least one chamber or cavity arranged so as to house water, and at least one pumping means for pumping water into and / or out of the chamber. In an embodiment, the variable ballast means comprises at least one vertically extending cavity, provided in a wall of one of or each of the outer member or the inner member, and at least one pumping means for pumping water into and / or out of either or both of the cavities. In certain embodiments, the at least one chamber is provided in a wall (or portion thereof) of the outer member, and / or either in a wall or hollow cavity of the inner member. More than one pumping means may be used, so as to, for example, provide for redundancy.

[0038] In another embodiment, the variable ballast means comprises multiple chambers or cavities. In one embodiment, the at least one chamber / cavity extends vertically. It would be readily understood by the skilled reader that the position and design of the variable ballast means can be altered or varied based on one or more of the desired or intended WEC apparatus operational requirements. For example, in use, the variable ballast may be adjusted by pumping water into and / or out of the cavity of the variable ballast means.

[0039] Typically, in operation of at least one embodiment, the heave motion of the outer and inner members is directly proportional to the draft. In one embodiment, for example, the depth or draft of the outer and inner members of the WEC apparatus can be adjusted so that each member will have a desired resonant frequency and phase relationship. In this manner, the ballast of the two members may be adjusted so that (i) at least one member is resonating in any given incident wave regime, (ii) the two members are heaving at different resonant frequencies, or (iii) the two members are heaving out of phase.

[0040] In an embodiment, the WEC apparatus is designed to have a predetermined Response Amplitude Operator (RAO). As the skilled reader would appreciate the RAO is a transfer function that equates the translation or rotation amplitude of an individual degree of freedom to the amplitude of the incident wave for a given wave frequency. The RAO can be used in the design of an embodiment of a WEC apparatus of the present disclosure. In an embodiment, a metacentric height of the WEC apparatus, when in use, is at least about 1 m.

[0041] In one embodiment, the RAO of the WEC apparatus may indicate the ratio of the linear motion response and linear incident wave amplitude. In one embodiment, the RAO can be used as a statistic or measure of the degree of optimisation or efficiency of the power output of the WEC apparatus. In certain embodiments the RAO is at least about 0.2m / m, or at least about 0.5m / m, or at least about 0.8m / m, or least about 1 .Om / m, or at least about 1 ,5m / m, or at least about 2.0m / m, or at least about 3.0m / m.

[0042] In an embodiment, the WEC apparatus is configured to be operably connected to or with the Power Take Off (PTO) module or PTO system, the PTO module or PTO system being configured to convert the relative motion between the outer member and the inner member into electrical power.

[0043] In an embodiment, the PTO module comprises at least one stationary member and at least one moving or movable member.

[0044] In an embodiment, both of the moveable and stationary members are operably accommodated, hosted or housed in one of the inner or outer members.

[0045] In an embodiment, the WEC apparatus is configured to be operably connected to or with multiple Power Take Off (PTO) module or systems. ln an embodiment, the outer and inner members are configurable to be operably coupled by one of a variety of PTO modules for use in converting the relative motion between the outer member and the inner member into electrical power.

[0046] In an embodiment, the WEC apparatus is configured so that the or each PTO module or system operates between the outer member and the inner member.

[0047] Embodiments of the WEC apparatus may be operably connected to or with known PTO modules or systems. Examples of suitable PTO modules that can be embodied or incorporated in embodiments of the WEC apparatus can include, but are not limited to, permanent magnet generators, switched reluctance linear generators, mechanical generators (eg. an example system is shown at URL https: / / www.wetgen.com / PTO_page.htm), hydraulic generators (eg. an example system is shown at URL https: / / www.researchgate.net / figure / Schematic- representation-of-the-hydraulic-PTO-of-a-heaving-wave-energy- converter_fig27_222604679), and pneumatic generators (eg. an example system is shown at URL https: / / www.youtube.com / watch?v=jFJ6s_5-v7E), or suitable variations of the latter types. In one embodiment, the switched reluctance linear generators are multi translator switched reluctance linear generators (or MSRLG’s) or suitable variations.

[0048] In an embodiment, the PTO module is coupled between the inner member and the outer member.

[0049] In another embodiment, the PTO module is provided in air and in a maintained atmosphere.

[0050] In an embodiment, the PTO module is housed in a cavity provided in the relevant member wall.

[0051] In an embodiment, one or each of the inner member or the outer member comprise at least one PTO housing or cavity so as to accommodate, host or house at least a portion of the PTO module. In certain embodiments the PTO housing or cavity is a vertically extending cavity. The PTO module may be positioned so that it can be readily accessed (using suitable infrastructure such as, for example, stairways, safety ladders, access landings, walkways, and / or the like) by an operator for operations and servicing / maintenance activities.

[0052] In an embodiment, the PTO module comprises a magnetic linear generator or permanent magnetic linear generator. In one embodiment, the linear generator comprises or is one produced by Trident Energy Limited (a datasheet for such examples can be found here: https: / / www.tridentenergy.co.uk / wp- content / uploads / 2014 / 01 / T rident-Energy-Linear-Generator-Datasheet.pdf). In one form, embodiments of PTO modules of this type find advantage because they have the least number of moving parts (eg. no gearboxes), least number of stages in the conversion process (eg. no hoses and / or accumulators etc), and, in many respects, can be the lowest in cost to fabricate and maintain with increased or superior reliability.

[0053] Embodiments of the WEC apparatus, advantageously, may be PTO module or system agnostic. For example, unlike other WEC technologies, embodiments of the inner and / or outer members of the WEC apparatus of the present disclosure can be configured so as to provide sizeable and / or variable payloads, thereby enabling provision for hosting, accommodating, or housing a large number of different weight combinations and / or loads for carrying various / extra equipment. Put simply, embodiments of the WEC apparatus configured consistent with the present disclosure can offer sufficient onboard capability for accommodating, hosting, or housing various equipment as might be required for a given application. This enables a wide variety of PTO modules to be used with the core principles of the WEC apparatus of the present disclosure.

[0054] In one form, the PTO module is a magnetic linear generator comprising a stationary member, such as a coil (formed, for example, of copper material), and a moving or moveable member, such as a permanent magnet, the at least one moveable member is configured so as to, in use, move vertically relative to the at least one stationary member.

[0055] In an embodiment, the at least one moveable member is a permanent magnet and the at least one stationary member is a coil.

[0056] In an embodiment, the at least one moveable member is a coil and the at least one stationary member is a permanent magnet.

[0057] The PTO module may be accommodated, hosted or housed by either the outer member or the inner member and coupled or anchored to or with the other or alternate member. In one embodiment, the coupling or anchoring is configured so that a portion of the PTO module is responsive to movement of said other / alternate member.

[0058] In one embodiment, the PTO module is accommodated, hosted or housed by the outer member; and the moving member is coupled or anchored (for example, in a mechanical manner) to or with the inner member. In one embodiment, the coupling or anchoring is configured so that a portion of the PTO module is responsive to movement of the inner member. In some embodiments, the latter configuration may be reversed.

[0059] In some embodiments, the moving member is arranged so as to slide or translate substantially vertically relative to the stationary member.

[0060] In an embodiment, the moving member is arranged so as to slide or translate internal of or within the stationary member in a substantially concentric or coaxial manner.

[0061] In another embodiment, the at least one moveable member is arranged so as to slide or translate internal of or within a respective stationary member in a substantially concentric or coaxial manner.

[0062] In a further embodiment, the at least one moveable member and the at least one stationary member are both housed and operable in either the inner member or the outer member.

[0063] In another embodiment, the at least one moveable member of the PTO module is operably coupled or anchored to or with the other of the inner member or the outer member so as to be moveable in response to movement of said other member when subject to the incident wave regime (or wave frequency of the incident wave regime).

[0064] In an embodiment, the stationary member extends a distance vertically in alignment of the inner or outer member that they are resident in or with.

[0065] In an embodiment, the stationary member extends vertically substantially the same length of the housing, and the moving member is shorter than the stationary member.

[0066] In an embodiment, the at least one stationary member and the at least one movable member is accommodated, hosted, or housed in the outer member, and the at least one moveable member is configured so as to follow movement of the inner member when moving in response to the incident wave regime.

[0067] In an embodiment, the at least one stationary member is accommodated, hosted, or housed in a generally vertically extending cavity formed in the outer member.

[0068] In an embodiment, the at least one moveable member is anchored with the inner member and extends or is supported from a portion of the inner member. In an embodiment, the at least one moveable member extends or is supported from a portion of the inner member.

[0069] In an embodiment, the at least one stationary member is one or more coil(s), and the at least one movable member one or more permanent magnet(s), the or each coil and the or each permanent magnet being accommodated, hosted or housed within the outer member.

[0070] In an alternative embodiment, the PTO module comprises a stationary member and a moving member accommodated, hosted or housed by the inner member, and the moving member is anchored to or with the outer member. In use, the relative motion of the inner member and the outer member, drives the vertical motion of the moving member relative to the stationary member thereby transforming wave energy to electrical power. In certain embodiments, the moving member is a permanent magnet and the stationary member is a coil. In alternative embodiments the moving member is a coil and the stationary member is a permanent magnet. In such embodiments, the coil may be formed of copper material.

[0071] In some embodiments, the PTO module comprises one or more coils arranged aligned coaxial within a cavity formed in one of the inner or outer members which houses, hosts or accommodates the coils. In an embodiment, the moving member (eg. a permanent magnet) is supported by a support associated with the other of the inner or outer members, supporting of the moving member configured so that the moving member translates or moves axially o coaxially relative the or each coils. In one form, the support is a piston or rod shaped form anchored with the relevant of the inner or outer members at or near an end of the support. The or each moving members being positioned along their respective piston so as to be moveable relative to the coil(s).

[0072] Embodiments of the WEC apparatus may comprise at least one PTO module. Some embodiments of the WEC apparatus may comprise multiple PTO modules.

[0073] Embodiments of the WEC apparatus may comprise two (2) or more PTO modules. In some examples, the WEC apparatus may comprise at least four (4) PTO modules, or at least six (6) PTO modules, or at least eight (8) PTO modules. The skilled reader will appreciate that any number of PTO modules can be used (eg. an even or odd number of PTO modules can be used). The number of PTO modules used may depend on balancing (eg. weight) requirements / distribution around the relevant of the outer / inner members, and / or the target rated capacity of an embodiment of the WEC apparatus, which could vary, for example, from about 1 MW to about 12MW or more. In one embodiment, the target rated capacity of an embodiment of the WEC apparatus may be about 8MW. In one embodiment, the target rated capacity of an embodiment of the WEC apparatus may be about 3MW.

[0074] For embodiments involving multiple PTO modules, the PTO modules may be spaced relative one another about either the outer or inner member, whichever hosts or houses the PTO modules, in a substantially uniform, even, equispaced manner about a respective axis of the relevant member. In this manner, the load distribution of the PTO modules can be distributed evenly or symmetrically about the relevant of the outer or inner members.

[0075] In an embodiment, the PTO module is configured so as to be operably connected to or with a PTO system. In one manner of implementation of use, the PTO system is arranged to transform the electricity produced by the PTO module into a grid quality electricity product. In one embodiment, the PTO system comprises one or more power conditioning module(s), inverter module(s), transformer module(s), switche(s), junctions box(es), and control system module(s).

[0076] In certain embodiments, the PTO system may be housed in at least one housing or enclosure or container. In one form, any such enclosure or container is configured of sufficient (eg. suitably rated / certified) weatherproofing. In one embodiment, the PTO system may be housed in at least one enclosure or container located on a structure or platform attached to a portion of the WEC apparatus. The or each enclosure or container may comprise a standard shipping container (for example, a 6ft, 10ft, 20ft or 40ft shipping container).

[0077] In an embodiment, at least one of the inner member or the outer member is in fixed communication with the PTO system housing member. In certain embodiments, the PTO system is provided on a platform, the platform being attached to either the inner member or the outer member of the WEC apparatus. In other embodiments, the PTO system may be housed in at least one enclosure or container located or contained in a wall, hull defining body of one of the outer or inner members.

[0078] In an embodiment, the PTO system may be connected to a dynamic sub-sea cable configured to provide the grid quality electricity product to an energy of electricity distribution means i.e. a grid. Dynamic sub-sea cables are known, and suitable cables would be readily identified by the skilled person.

[0079] In an embodiment, the PTO system comprises a control system, the control system configured so as to, in use, (i) measure and monitor WEC performance and input variables, and (ii) adjust variable parameters of the WEC to optimize power absorption, conversion and / or production output. In an embodiment, the PTO system further comprises at least one module selected from the group consisting of a power conditioning module, a monitoring module, and a measuring module.

[0080] In an embodiment, the PTO system comprises a measuring module, and the measuring module measures at least one variable selected from the group consisting of displacement, velocity, acceleration, pressure, approaching wave height, wave period, power absorption, power conversion, power production, power output and geographical positioning.

[0081] In one embodiment, the WEC apparatus may be operably connected to a mooring system. In such embodiments, the mooring system may comprise an upper attachment portion attached to the outer member of the WEC apparatus, and a lower attachment portion attached to the seabed or ocean floor. The mooring system may be configured to substantially limit horizontal movement of the WEC apparatus while allowing vertical relative movement of the outer and inner members. In some embodiments, the mooring system may be configured so as to limit rotational movement of the outer member. The skilled reader will appreciate other types of mooring systems that can be used in the present context. For example, suitable examples of mooring systems include, but are not limited to, 3-point, 4pt, 5pt and 6pt spread catenary mooring systems.

[0082] Embodiments of the WEC apparatus may also be connected to mooring systems using semi-taut or tension leg moorings.

[0083] Embodiments of the WEC apparatus may also be connected to mooring systems using shared anchors of adjacent WEC apparatuses. In some arrangements, use of a shared anchor type mooring system could allow for multiple moorings for different embodiments of the WEC apparatuses, thus reducing the average number of anchors per WEC apparatus below the number of moorings required for a single WEC apparatus.

[0084] In various embodiments, multiple or arrays of embodiments of WEC apparatus of the present disclosure, as well as embodiments where multiple WEC apparatus are used to form broader energy conversion apparatus (eg. using two, three, four or more WEC apparatus of the present disclosure), are connected together via shared mooring lines or systems.

[0085] In one embodiment, the WEC apparatus further comprises at least one releasable locking means or arrangement configured to lock the outer and inner members together in certain situations, such as for example, severe weather events. In one embodiment, the WEC apparatus comprises at least two locking means. Suitable locking means or arrangements include (non-exhaustively) electrical locking systems, mechanical locking systems, hydraulic locking systems or pneumatic locking systems. The skilled reader will appreciate other forms of locking arrangements suitable for use in the present context. Locking systems could be embodied with PTO modules or couplings.

[0086] Without being bound by scale testing of various embodiments of the principles of the present disclosure tested to date, a number of geometric relationships or parameters are considered to play a role in the design of the WEC apparatus of the present disclosure.

[0087] In accordance with a first geometric relationship, a ratio between the draft of the outer member to the dimension defining the outer most diameter of the outer member, is about 3:1 or less, or between a range of from about 1 :1 to about 3:1 , or less than 1 :1. The draft parameter of the outer and / or inner member may be informed by the hydrodynamic response to the waves at the intended operating site / location, and / or the depth of water of the intended location of operation, and then fixed thereby driving the geometric configuration of the outer member.

[0088] In accordance with a second geometric relationship, a ratio between the cross- sectional area of the outer and inner members is about 0.5:0.5, where 1.0 represents 100 percent of the cross-sectional area enclosed by an outer diameter of the outer member. In other embodiments, a ratio between a cross-sectional area of the outer and inner members is from about 0.5:0.5 to about 0.7:0.3 or to about 0.3:0.7, or from about 0.7:0.3 to about 0.3:0.7, where 1.0 represents 100 percent of the cross- sectional area enclosed by an outer diameter of the outer member. In certain embodiments, the diameter of the outer and inner members is determined by the wave length of the target incident waves.

[0089] In an embodiment, the apparatus further comprises a sponson provided with the outer member, and positioned so as to be semi-submerged or submerged at or near the surface of the body of water in which the apparatus is deployed.

[0090] In an embodiment, the apparatus further comprises a heave plate provided with the outer member, and positioned so as to be at or near a distal submerged end of the outer member.

[0091] In an embodiment, the apparatus comprises a heave plate provided with the inner member, and positioned so as to be at or near a distal submerged end of the inner member. In an embodiment, the or each heave plate(s) are configured so as to add additional mass to reduce or minimise motion of the relevant of the inner or outer member hosting the relevant heave plate(s).

[0092] In an embodiment, the apparatus further comprises a solar harvesting means, module, or system configured for use in harvesting solar energy for use in generating electrical energy for producing a second energy product.

[0093] In an embodiment, the solar harvesting means, module, or system comprises one or more solar panel(s) or solar panel array(s).

[0094] In an embodiment, the or each solar panel or solar panel array are in communication with a or the subsea power cable configured to provide the first and / or second energy product(s) to an or the energy distribution means, for example, via a subsea cable.

[0095] In an embodiment, the apparatus further comprises an electrical storage means or module (eg. one or more batteries or arrays of batteries) for storing the first energy product harvested via the PTO module / system and or the second energy product harvested from the or each solar panel(s) or solar panel array(s).

[0096] In an embodiment, the electrical storage means or module is in communication with a or the subsea power cable configured to provide the first and / or second energy product to an or the energy distribution means.

[0097] It will be appreciated that each of the first (generated via the PTO module(s)) or second (generated via the solar harvesting means / system) energy products can be either supplied direct to the energy distribution means via the subsea cable, or, to the electrical storage means / module. Accordingly, any of the generated electrical power may go direct to the export subsea power cable, or may get to the export subsea power cable via the electrical storage means / module.

[0098] In an embodiment, the apparatus is provided in the form of a hybrid energy conversion apparatus or a floating hybrid energy conversion apparatus.

[0099] In a fourth aspect, an embodiment provides a method for generating energy, the method comprising the steps of: (a) providing a first vertically extending outer member, and a second vertically extending inner member; (b) adjusting the ballast of the first and / or second members to a predetermined depth or draft, wherein, in use, the depth or draft of the first and second members is determined to ensure at least one of the first and second members is moving or resonating in response to an incident wave regime.

[0100] In one embodiment, the step of adjusting the ballast of the first and / or second members to a predetermined depth or draft, comprises adjusting a variable ballast means of at least one of the first and second members to a predetermined weight.

[0101] In another embodiment, the variable ballast means is configured to be ballasted (or weighted) by water.

[0102] In a further embodiment, water is added to or removed from the variable ballast using one or more pumps, such as, for example, a submersible or bilge pump. In certain embodiments, adjustments to variable ballast may be controlled or controllable by a control system. The control system may be arranged so as to enable adjustment of the variable ballast based on one or more factors, including, for example, forecast reports and real-time wave monitoring system outputs. In certain embodiments, variable ballast may be adjusted or adjustable as required, for example, when there is a change in average incident wave frequency.

[0103] In one embodiment, variable or passive ballasting may involve using a compressible fluid (eg. compressed air) to push ballast water held in a ballast tank or chamber out of a valve below the water line. Said valve (or any other valve in fluid communication with the ballast tank or chamber holding the compressed fluid) can be opened (eg. in a selective manner) so as to passively allow water into the relevant ballast tank or chamber as desired. In some embodiments, variable or passive ballast means are configured adjustable for extreme conditions (eg. ‘survival’ conditions) so as to provide or converge toward a desired or predetermined optimal draft or freeboard condition of one or both of the outer or inner members, that may be in accordance with technical engineering / considerations.

[0104] In one embodiment, a first pump (eg. a submersible or bilge pump) is provided inside of a respective ballast tank or chamber of the variable ballast means and configured operable for removing water held inside the ballast tank or chamber to external environs. In an embodiment, a second pump is provided external of the ballast tank or chamber of the variable ballast means and configured operable for pumping water from the external environs into the ballast tank or chamber.

[0105] In an embodiment, the vertically extending members of the WEC apparatus may be designed or engineered according to the requirement of the geographical location of the desired or intended operation. The range of depths available is a function of the range of target wave periods and other considerations, such as required metacentric height, desired freeboard, water depth and the physical dimensions of the WEC apparatus.

[0106] In an embodiment, the first member is the outer member and the second member is the inner member, wherein in the outer member is configured so as to receive the inner member for enabling the inner member to be slidable relative to the outer member.

[0107] In certain embodiments, the metacentric height (or measure of the initial static stability of a floating body) of the WEC apparatus is greater than about 0.5m, or greater than about 1 m, or greater than about 1 ,5m, or greater than about 2m, or greater than about 3m, or greater than about 5m, or greater than about 10m.

[0108] In an embodiment, the method of the present aspect is carried our in respect of an embodiment of a WEC apparatus or system as described herein.

[0109] In one embodiment, the design of the WEC apparatus is dependent on required freeboard and / or draft considerations. The required freeboard of the WEC apparatus may depend on or be informed by the maximum expected wave height in storm conditions.

[0110] In another embodiment, the WEC apparatus may be designed such that in storm conditions, the wave does not break over the top of the structure. However, embodiments of the WEC apparatus may be designed where this occurs. In certain embodiments the required length or height of the WEC apparatus may be a function of draft and / or freeboard. In certain embodiments, when a variable ballast of the WEC apparatus is closer to zero percent (%) capacity, the WEC apparatus is minimising draft and maximising freeboard (“light ships”), and when variable ballast is closer to 100 percent (%) capacity the WEC apparatus is maximising draft and minimising freeboard (“heavy ships”).

[0111] In an embodiment, the design of the WEC apparatus is dependent on or informed by one or more physical restraints. For example, the depth of any given geographical location may influence the total length of the WEC apparatus. In certain embodiments, the WEC apparatus is designed such that there is a predetermined clearance between the bottom or base surface of the WEC apparatus at maximum ballast and the seabed. The total length and ballastability of the WEC apparatus may also be adjusted to ensure integrity of the dynamic export cable (eg. subsea cable).

[0112] In certain embodiments, the diameter of the outer and inner members is, at least in part, determined or informed by reference to the wave length of the target incident waves. In an embodiment, the method of the present aspect further comprises providing a power take off device (PTO) module operably connected between the first and second members, wherein the relative motion of the first and second members drives the PTO module and transforms wave energy to electrical power.

[0113] In an embodiment, the method comprises (i) measuring and / or monitoring WEC apparatus performance and input variables, and (ii) adjusting variable parameters of the WEC apparatus to optimize power absorption, conversion and / or production output.

[0114] In an embodiment, the first and second members are ballasted to different depths or drafts relative to one another. In certain embodiments, the first and second members resonate at different wave frequencies. In an embodiment, the first and second members resonate out of phase with each other. Typically, the amount of electricity produced by the PTO module is a function of relative velocity and relative force of the first and second members.

[0115] In an embodiment, the PTO is a magnetic linear generator comprising at least one moveable member and at least one stationary member.

[0116] In another embodiment, the moveable member is a permanent magnet and the stationary member is a coil, or vice versa.

[0117] In a further embodiment, the at least one stationary member and at least one moveable member are housed by the first outer member and the moveable member is configured to move vertically through the stationary member.

[0118] In another embodiment, the at least one moveable member is structurally anchored to or with the second inner member. It would be readily understood that the at least one stationary member and at least one moveable member may be provided on the second inner member with the at least one moveable member structurally anchored to or with the first outer member. In use, the relative vertical motion of the first and second members drives the moveable member past the stationary member to generate electrical power.

[0119] In an embodiment, the moveable member is a permanent magnet, and the stationary member is a coil.

[0120] In an embodiment, the moveable member is a coil and the stationary member is a permanent magnet. In an embodiment, the step of adjusting a ballast of at least one of the first and second members, is performed by a control system.

[0121] In an embodiment, the electrical product is a first energy product, and the method further comprises providing for operation one or more solar panel(s) or array(s) of solar panels for use in generating a second electrical product.

[0122] In an embodiment, the method further comprises storing the first and / or second electrical product in a storage means or module.

[0123] In an embodiment, the method further comprises distributing the first and / or second electrical product to a distribution means.

[0124] In an embodiment, the method further comprises distributing the first and / or second electrical products to an electrical grid.

[0125] In an embodiment, the PTO is any one of the following: linear generator(s), mechanical generator(s), hydraulic generator(s) and pneumatic generator(s), permanent magnet generator(s), switched reluctance linear generator(s), multi translator switched reluctance linear generator(s), or as otherwise described herein.

[0126] According to a fifth aspect, an embodiment provides a wave energy conversion (WEC) apparatus comprising: an outer member and an inner member, wherein at least one of the outer member or the inner member is configured to move in response to an incident wave regime, a power take-off (PTO) module comprising a moveable member and a stationary member, and configured so that both the moveable and stationary members are accommodated, hosted or housed in one of the inner or outer members, with the moveable member being operatively coupled or anchored to or with the other of the inner or outer members, and wherein, in use, relative motion between the moveable member and the stationary member is used to generate power.

[0127] Embodiments of the WEC apparatus of the present aspect may incorporate any of the features, either individually or in combination, described in relation to the WEC apparatus of the first, second, or third aspects described above, or as other described herein. According to a sixth aspect, an embodiment provides a floating support structure comprising a plurality of interconnected WEC apparatuses according to the first, second, third or fifth aspects, or as otherwise described herein.

[0128] Embodiments of the method of the fourth aspect may be carried out using embodiments of the WEC apparatuses according to the first, second, third, fifth, or sixth aspects, or those as otherwise described herein.

[0129] In an embodiment, the plurality of WEC apparatuses are interconnected such that each apparatus defines a corner of the floating support structure.

[0130] In an embodiment, the plurality of WEC apparatuses are interconnected by one or more rigid connector(s).

[0131] In an embodiment, the floating support structure is semi-submerged insofar as, in use, it defines a submerged portion, and a portion that, in use, is located above the surface of the body of water in which it is deployed.

[0132] In an embodiment, the one or more rigid connectors interconnecting at least two apparatuses together are submerged, and comprise one or more tanks or chambers that are operable for use in providing ballast or buoyancy to the floating support structure for ballasting the floating support structure to different drafts or depths.

[0133] In an embodiment, the one or more rigid connectors interconnecting at least two apparatuses together are submerged, and comprise one or more hole or apertures enabling the or each rigid connectors to be flooded. Alternatively, the or each rigid connectors could be sealed so they are always full of air.

[0134] In an embodiment, the one or more tanks or chambers of the or each rigid connectors are arranged in fluid communication with a ballasting means of one or more of the apparatuses.

[0135] In an embodiment, the portion of the floating support structure or one or more of the rigid connectors that are above or below the surface of the body of water in which the floating support structure is deployed are configured so as to support any of the following: a deck or platform structure, maintenance equipment, monitoring equipment, control equipment, ballasting pumping modules, accommodation / office utilities, maintenance repair stores, solar panel arrays, electrical storage equipment, auxiliary / emergency power equipment, communications equipment, one or more access walkways, a helicopter take-off / landing / recharging infrastructure, a wind turbine, water desalination equipment, hydrogen generating equipment or associated product export equipment, tidal or current driven generator, chemical storage, unmanned aerial vehicle take-off / landing infrastructure, autonomous underwater vehicle docking / recharging infrastructure.

[0136] In an embodiment, the floating support structure is tethered or moored to the seabed.

[0137] In an embodiment, the floating support is adapted or configured to support a further apparatus or equipment such as a platform, a wind turbine, tidal or current driven generator, or hydrogen generating equipment, ammonia generating equipment.

[0138] In an embodiment, the floating support structure further comprises a solar harvesting means, module or system.

[0139] In an embodiment, the floating support structure further comprises a structure configured to cover across a portion of the floating support structure, the structure configured so as to support a solar harvesting means, module or system thereon for use in harvesting solar energy.

[0140] In an embodiment, the structure is configured for providing a roof or canopy structure atop which one or more solar panel(s) or solar panel array(s) of the solar harvesting means, module or system are positioned.

[0141] In an embodiment, the floating support structure comprises an electrical storage means or module for storing the first energy product harvested via the PTO module / system and or the second energy product harvested from the or each solar panel(s) or solar panel array(s).

[0142] In an embodiment, the electrical storage means or module is in communication with a or the subsea power cable configured to provide the first and / or second energy product(s) to an or the energy distribution means.

[0143] In another aspect, an embodiment provides a method of forming or providing an embodiment of (i) a wave energy conversion (WEC) apparatus of the first or third aspects described above, or as otherwise described herein, or (ii) a floating support structure comprising a plurality of interconnected WEC apparatuses according to the fourth aspect described above, or as otherwise described herein.

[0144] In a further aspect, an embodiment provides a method of operating (i) a wave energy conversion (WEC) apparatus of the first or third aspects described above, or as otherwise described herein, or (ii) a floating support structure comprising a plurality of interconnected WEC apparatuses according to the fourth aspect described above, or as otherwise described herein.

[0145] In a further embodiment, the floating support is configured to support a second apparatus, or member. In certain embodiments, the second apparatus could be any apparatus or equipment. In one embodiment, the second apparatus, member, or equipment is any of the following (non-exhaustively): a platform, a wind turbine, water desalination equipment, tidal or current driven generator, hydrogen generating equipment or associated product export facilities. The skilled reader will appreciate other types of apparatus or equipment that could provide convenience or utility in the context of the present disclosure.

[0146] In accordance with a further aspect an embodiment provides a wave energy conversion (WEC) apparatus comprising an outer member and an inner member, wherein at least one of the outer member and the inner member is configured to resonate with a wave frequency, and wherein in use, relative motion between the outer member and the inner member is used to generate electrical power.

[0147] In accordance with a further aspect of the invention there is provided a method for generating energy, the method comprising:

[0148] (i) providing first and second vertically extending members which move relative to each other;

[0149] (ii) providing the first and second vertically extending members at a predetermined depth or draft, wherein the depth or draft of the first and second vertically extending members is configured to ensure at least one of the first and second vertically extending members is moving in response to an incident wave regime.

[0150] In another aspect, an embodiment provides an energy conversion apparatus or system comprising: a plurality of wave energy conversion (WEC) apparatus arranged according to any of the wave energy conversion apparatus of the first, second, third, fifth aspect, or the floating support structure of the sixth aspect, or as otherwise described herein, for use in generating a first energy product and arranged in spaced relation by connecting structure, a solar harvesting means, module, or system for use in generating a second energy product, wherein, in use, the first and / or second energy products are distributable to an energy distribution means.

[0151] In an embodiment, the connecting structure interconnects said WEC such that each apparatus defines a corner of the energy conversion apparatus.

[0152] In an embodiment, the plurality of apparatuses are interconnected by one or more rigid connector(s).

[0153] In an embodiment, the apparatus is semi-submerged insofar as, in use, it defines a submerged portion, and a portion that, in use, is located above the surface of the body of water in which it is deployed.

[0154] In an embodiment, the one or more rigid connectors interconnecting at least two apparatuses together are submerged, and comprise one or more tanks or chambers that are operable for use in providing ballast or buoyancy to the for ballasting the energy conversion apparatus to different drafts or depths.

[0155] In an embodiment, the one or more tanks or chambers of the or each rigid connectors are arranged in fluid communication with a ballasting means of one or more of the apparatuses.

[0156] In an embodiment, the portion of the energy conversion apparatus or one or more of the rigid connectors that are above or below the surface of the body of water in which the energy conversion apparatus is deployed are configured so as to support any of the following: a deck or platform structure, maintenance equipment, monitoring equipment, control equipment, ballasting pumping modules, accommodation / office utilities, maintenance repair stores, solar panel arrays, electrical storage equipment, auxiliary / emergency power equipment, communications equipment, one or more access walkways, a helicopter take- off / landing / recharging infrastructure, a wind turbine, water desalination equipment, hydrogen generating equipment or associated product export equipment, tidal or current driven generator, chemical storage, unmanned aerial vehicle take-off / landing infrastructure, autonomous underwater vehicle docking / recharging infrastructure.

[0157] In an embodiment, the energy conversion apparatus is tethered or moored to the seabed.

[0158] In an embodiment, the energy conversion apparatus is adapted or configured to support a second apparatus or member such as a platform, a wind turbine, tidal or current driven generator, hydrogen generating equipment, or ammonia generating equipment

[0159] In an embodiment, the energy conversion apparatus further comprises a structure configured to cover across a portion of the energy conversion apparatus, the structure configured so as to support the solar harvesting means, module or system.

[0160] In an embodiment, the structure is configured for providing a roof or canopy structure atop which the solar harvesting means, module or system is positioned.

[0161] In an embodiment, the energy conversion apparatus comprises an electrical energy storage means or module for storing the first energy product harvested via the PTO module / system and or the second energy product harvested from the or each solar panel(s) or solar panel array(s).

[0162] In an embodiment, the electrical energy storage means or module is in communication with a or the subsea power cable configured to provide the first and / or second energy product to an or the energy distribution means.

[0163] In an embodiment, the first and. / or second energy products may be supplied to the electrical energy storage means or module or direct to the subsea cable.

[0164] In an embodiment, the apparatus is a hybrid energy conversion apparatus or a floating hybrid energy conversion apparatus.

[0165] In this specification, where a literary work, act or item of knowledge (or combinations thereof), is discussed, such reference is not an acknowledgment or admission that any of the information referred to formed part of the common general knowledge in the art, in Australia or any other country. Such information is included only for the purposes of providing context for facilitating an understanding of the inventive concept / principles and the various forms or embodiments in which those inventive concept / principles may be exemplified.

[0166] It is to be understood that each document, reference, patent application or patent cited in this text is expressly incorporated herein in their entirety by reference, which means that it should be read and considered by the reader as part of this text. That the document, reference, patent application, or patent cited in this text is not repeated herein is merely for reasons of conciseness.

[0167] Various aspects, examples or embodiments described herein can be practiced alone or in combination with any one or more of the other described aspects, examples or embodiments, as will be readily appreciated by those skilled in the relevant art. The various described aspects, examples or embodiments can optionally be provided in combination with one or more of the optional features described in relation to the other aspects, examples or embodiments. Furthermore, optional features described in relation to one aspect, example or embodiment can optionally be combined alone or together with other features described in relation different aspects, examples or embodiments.

[0168] For the purposes of summarising the various aspects, examples, or embodiments exemplifying the principles described herein, certain aspects, advantages and novel features have been described above and herein. It is to be understood, however, that not necessarily all such advantage(s) may be achieved in accordance with any particular embodiment or carried out in a manner that achieves or optimises one advantage or group of advantages as taught herein without necessarily achieving other advantage(s) as may be taught or suggested herein.

[0169] Brief Description of the Drawings

[0170] Embodiments will now be described, by way of example only, with reference to the accompanying non-limiting figures, in which:

[0171] Figure 1 is a perspective view of a wave energy conversion apparatus according to a first embodiment of the first aspect of the subject disclosure;

[0172] Figures 2 is a cut away perspective view of the wave energy conversion apparatus of Figure 1 to show further detail of the wave energy conversion apparatus;

[0173] Figures 3A to 3D show the member walls of the wave energy conversion assembly from different views;

[0174] Figure 4 shows a perspective view of a structure comprising a number of wave energy conversion apparatus arranged consistent with the present disclosure;

[0175] Figure 5 shows a plan view of the structure shown in Figure 4;

[0176] Figure 6 shows an elevation view of an upper portion of one of the wave energy conversion apparatus of the structure shown in Figures 4 and 5;

[0177] Figure 7 shows an elevation view of one side of the structure shown in Figures 4 to 6;

[0178] Figure 8 is a perspective view of a platform or floating platform or floating energy conversion apparatus according to one embodiment of an aspect of the present disclosure;

[0179] Figure 9 shows an elevation view of an upper portion of another embodiment of the wave energy conversion apparatus of the present disclosure (incorporating a sponson arrangement);

[0180] Figure 10 shows a perspective view of an embodiment of a wave energy conversion apparatus / system arranged consistent with the present disclosure, having a solar harvesting means.

[0181] Figure 11 shows an elevation view of the wave energy conversion apparatus / system of the (roof) structure shown in Figure 10.

[0182] Figure 12a shows an embodiment of a wave energy conversion apparatus carrying a sponson structure; Figure 12b shows an embodiment of a wave energy conversion apparatus carrying a heave plate at the distal end of the outer member; and Figure 12c shows an embodiment of a wave energy conversion apparatus carrying a heave plate at the distal end of the inner member.

[0183] Figure 13 shows a schematic diagram of one embodiment of a locking means or mechanism for the embodiment of the WEC apparatus shown in Figure 1, shown in an unlocked state or condition.

[0184] Figure 14 shows a schematic diagram of the embodiment of the locking means or mechanism shown in Figure 13, shown in a locked state or condition where relative movement between the inner and outer members is prevented.

[0185] Figure 15 shows a schematic diagram of one embodiment of an end stop means or arrangement for the embodiment of the WEC apparatus shown in Figure 1, the end stop means or arrangement shown in an inoperative condition or state.

[0186] Figure 16 shows a schematic diagram of the embodiment of the end stop means or arrangement shown in Figure 15, the end stop means or arrangement shown in an inoperative condition or state.

[0187] Figure 17 shows a schematic diagram of the embodiment of the end stop means or arrangement shown in Figures 15 and 16, the end stop means or arrangement shown in an operative condition or state where the topside structure of the inner member has contacted the end stop elements.

[0188] Figure 18a shows a schematic diagram of one embodiment of a guide means or arrangement of the embodiment of the WEC apparatus shown in Figure 1 during operation.

[0189] Figure 18b shows a schematic diagram (viewed from above) of an embodiment of a guide means incorporated with an embodiment of the WEC apparatus arranged consistent with the present disclosure.

[0190] Figure 19a shows a schematic diagram of one embodiment of a guide means or arrangement for reducing or preventing relative rotational or yaw movement between the inner member and the outer member of the embodiment of the WEC apparatus shown in Figure 1 during operation.

[0191] Figure 19b shows a schematic diagram of section Z1-Z2 as indicated in Figure 19c.

[0192] Figure 19c shows a schematic diagram (elevation view of a vertical cross-section) of the guide means shown in Figure 18b.

[0193] Figure 19d shows (i) a schematic diagram of a plan view of an embodiment of a guide means operable for maintaining alignment of the inner and outer members relative the axis X; and (ii) a schematic cross section of an elevation view of that depicted in (i).

[0194] Figure 20 shows a schematic diagram of an embodiment of a single WEC apparatus arranged consistent with the present disclosure, using a hydraulic PTO module arrangement.

[0195] Figure 21 shows a schematic diagram of an embodiment of a single WEC apparatus arranged consistent with the present disclosure, using a mechanical PTO module arrangement.

[0196] Figure 22 shows a schematic diagram of an embodiment of a single WEC apparatus arranged consistent with the present disclosure, using a pneumatic PTO module arrangement.

[0197] Detailed Description

[0198] The present invention is not to be limited in scope by any of the specific embodiments described herein. These embodiments are intended for the purpose of exemplification only. Functionally equivalent products and methods are clearly within the scope of the invention as described herein. The invention described herein may include one or more range of values (e.g. size etc). A range of values will be understood to include all values within the range, including the values defining the range, and values adjacent to the range which lead to the same or substantially the same outcome as the values immediately adjacent to that value which defines the boundary to the range.

[0199] Throughout the specification and the claims that follow, unless the context requires otherwise, the word “comprise” or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

[0200] Furthermore, throughout the specification and the claims that follow, unless the context requires otherwise, the word “include” or variations such as “includes” or “including”, will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

[0201] Other definitions for selected terms used herein may be found within the detailed description of the invention and apply throughout. Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which the invention belongs.

[0202] Embodiments exemplifying the principles of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments are shown. The principles of the present disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the principles to those skilled in the art.

[0203] For conciseness of description, like numbers refer to like elements throughout. In the various Figures the same reference numerals have been used to identify similar elements.

[0204] With reference to Figures 1 and 2, there is provided one embodiment of a wave energy conversion (hereinafter, WEC) apparatus 10 exemplifying the principles of the present disclosure that is adapted or configured to be at least partially submerged in a body of water 12. The WEC apparatus 10 comprises an outer member 14 and an inner member 16. Broadly, at least one of the outer 14 and inner 16 members is configured so as to move in response to an incident wave regime to which the WEC apparatus 10 is or becomes subject to, whereby, in use, relative motion between the outer 14 member and the inner 16 member is used to generate power.

[0205] The WEC apparatus 10 is operably connected to at least one Power Take Off (or PTO) module - shown generally in Figures 3A to 3D as reference 21. With reference to the specific embodiment shown in Figure 1 and Figure 3A, at least a portion of the PTO module 21 is accommodated, hosted or housed in the outer member 14 and structurally coupled or anchored to or with the inner member 16 by way of a coupling arrangement 29 (described below) which can be or be part of the PTO module 21.

[0206] As shown in Figure 1, when the WEC is in situ the outer member 14 is a vertically extending member, having an opening 18 that extends vertically therethrough. The inner member 16 is a vertically extending enclosed cylindrical member which is provided to nest within the opening of the outer member 14. Both the outer 14 and inner 16 members are arranged so as to align (in an ‘in use’ condition) substantially concentric or coaxial one another relative to a generally vertically aligned axis X. In this manner, the inner 16 and outer 14 members are arranged in a nested or sleeved relation, as shown in Figure 1. The outer member 14 is operably connected to the inner member 16 by way of a guide means (not shown but described in further detail below). Broadly, the guide means allows for the outer 14 and inner 16 member to move vertically relative to each other in respect of the axis X, whilst limiting movement and, in certain embodiments, limiting axial motion. In use, the relative vertical motion of the outer member 14 and inner member harnesses kinetic energy to generate power (eg. in the form of electricity).

[0207] A cross-sectional shape of each of the outer 14 and inner 16 members is generally symmetrical (each of the members 14, 16 being of cylindrical form) about their respective longitudinal and vertically aligned axes. The use of a generally symmetrical shape or profile offers advantage in that the operation of the shape or profile (and consequentially, for example, the operational performance of the WEC apparatus 10) does not depend on wave direction and any need to incorporate a weather vaning or heading control system.

[0208] However, other embodiments of the outer 14 or inner 16 members possessing symmetry about the vertical plane (eg. an oval cross-sectional shape / profile) may find use with embodiments of the WEC apparatus 10. For example, for a case where at least the outer member 14 comprises an oval cross-section shape, alignment of the narrowed portion of the oval shape can be aligned so as to face the incident wave regime thereby minimising hydrodynamic drag about the outer member 14. In these embodiments, the WEC apparatus 10 may be provided with a suitable propulsion and control technologies (eg. dynamic positioning technology) operable for enabling continuous / ongoing positional adjustment of the WEC apparatus 10 relative to the incident wave regime as wave conditions require.

[0209] The outer member 14 is operably connected or slidably retained to or with the inner member 16 by the guide means. In various implementations of use, the guide means may be configured so as to allow generally vertically aligned movement of the inner 14 and outer 16 members relative to each other during operation. In some embodiments, the guide means may be configured so as to limit yaw or “twist” (eg. rotational movement about the axis X) and / or, in some embodiments, limiting axial movement of the outer 14 and inner 16 members relative to each other. It will be appreciated by the skilled reader that the guide means can be any arrangement which operates to allow or enable generally vertically aligned movement of the outer 14 and inner 16 members relative to each other. In some embodiments, the guide means may be configured so as to enable relative movement between the outer 14 and inner 16 members that aligns with the vertical axis X, while operating to prevent or limit / minimise relative rotation (eg. yaw, twisting) about the vertical axis X. In this manner, the focus is to maximise the scope of linear relative movement that is along the axis X. Examples of suitable guide means / arrangements may include, but are not limited to, any suitable keyway arrangements, track systems, static guide systems, bearing systems, roller systems, or prismatic coupling arrangements that operate to guide relative movement between the outer 14 and inner 16 members.

[0210] An example of a fit-for-purpose guide means (360) is shown in Figure 18a (general cross section view shown). The guide means 360 is provided in the form of bearing modules 360a, 360b. It will be appreciated that more bearing modules could be used, such as, for example, three or four bearing modules equispaced about the axis X as required. Two bearing modules 360a, 360b are shown for explanative purposes.

[0211] With reference to Figure 18a each bearing module 360a, 360b comprises a respective bearing support assembly 364a, 364b. Each bearing support assembly 364a, 364b comprises a respective bearing 366a, 366b that is held and supported in position between two spaced apart parallel aligned structural plates (370a, 370b, only one shown in Figure 18a). Each bearing 366a, 366b is supported by its supporting structural plates 370a, 370b in a manner in which the outer circumference of the bearing (366a, 366b) projects inward and offset from the interior wall of the outer member 14 as shown, which bearing (366a, 366b) runs in rolling contact with the exterior wall of the inner member 16 during operation. The spaced apart parallel aligned structural plates 370a, 370b are structurally connected at a base of the respective bearing assembly 364a, 364b. Each respective bearing support assembly 364a, 364b is fastened via its base to the upper portion of the outer member 14 so as to be in fixed relation therewith. In this manner, the inner member 16 is located in concentric or coaxial relation with the outer member 14 relative to the axis X, and is enabled with freedom of movement so as to move along the axis X relative to the outer member 14. As noted, while two bearing modules 360a, 360b are shown, any number can be used as is considered necessary. The skilled reader will appreciate other ways in which the same functional purpose can be achieved.

[0212] Figure 18b and Figure 19b show an embodiment of the guide means comprising three bearing modules 360a, 360b, 360c (collectively, 360) that are fixed to the upper portion or surface of the outer member 14 and equispaced about the axis X (refer Figure 19c also for reference). In order to manage relative rotation of the inner 16 and outer 14 members about the axis X, fin elements 367-1 / 4 are positioned (vertically aligned) on the exterior wall of the inner member 16 so as to be interactable with a proximally disposed bearing module 360. As shown, fins 367-1 and 367-2 are positioned either side of bearing module 360a. In this manner, fins 367-1 / 2 can interact with respective corresponding sides of the bearing module 360a should relative rotational alignment between the inner 16 and outer 14 members divert from the configuration shown in Figure 18b. Fins 367-3 and 367-4 are positioned on the exterior wall of the inner member 16 intermediate the bearing modules 360b and 360c as shown. Similarly, should relative rotational alignment between the inner 16 and outer 14 members divert from the configuration shown, fin 367-3 is available to interact with bearing module 360-b, and fin 367-4 is available to interact with bearing module 360-b in order to prevent unwanted relative rotation / yaw relative to the axis X.

[0213] With reference to Figure 19a (general cross section view shown), the guide means 360 further comprises pads 375a, 375b which are disposed on the lower surface of the outer member 14. Each of the pads 375a, 375b are positioned so as to assist in spacing the inner member 16 from the outer member 14 so as to match the spacing achieved by the bearing modules 370a, 370b, and ensuring that the inner member 16 is able to move relative to the outer member 14 in accordance with axis X. During operation, the pads 375a, 375b run against the inner member 16 (eg. similar as for wear pads) helping to centralise the bottom or foot region of the inner member 14 relative to the outer member 14. In this manner, lateral stabilisation of the inner member 16 can be achieved relative to the outer member 14.

[0214] Figure 19a also shows an alternative embodiment using elongate pads 375a’, 375b’ which are, as shown, attached to the inner wall of the outer member 14 and positioned so as to be aligned in a generally vertically manner. It will be appreciated that the pads 375a’, 375b’ could be positioned anywhere on the inner wall of the outer member 14, and could, for example, be positioned on the exterior wall of the inner member 16 depending on the specific requirements for a given project.

[0215] While two pads 375a, 375b (and pads 375a’, 375b’) are shown for explanative purposes, it will be appreciated that more pads 375a, 375b (and pads 375a’, 375b’) could be used, such as, for example, three or four pads equispaced about the axis X as required.

[0216] Relative rotational movement between the inner 16 and outer 14 member can also be managed. In this manner, the pads 375a, 375b (and the pads 375a’, 375b’) may be provided with, or operable with, a key means which functions to interact with the inner member 16 so as to limit, reduce or prevent relative movement between the inner 16 and outer 14 members in yaw or rotation about the axis X.

[0217] Figure 19b shows an arrangement using three pads 375a’, 375b’, 375c’ (attached and aligned vertically on the inner wall of the outer member 14 as shown) equispaced about the axis X to assist in providing lateral stability so as to centralise both members 14, 16 concentric / coaxial (laterally) relative the axis X.

[0218] The pads 375, 375’ may be formed from various materials having low friction and wear capacity characteristics. In one form, the pads (and the bearing 366) may be formed of vesconite material - this being similar to a teflon material, having low friction, long lasting performance, and being relatively easy to work with. Vesconite has shown to work well in and out of water, and can be galvanized to or bolted to steel for use as a wear pad. Other materials having like or analogous characteristics may have benefit for use with the present disclosure. The skilled reader would understand that the thickness, number and position of the pads can be determined by engineering.

[0219] Figure 19d shows an embodiment of a guide means 600 that is operable for maintaining alignment of the inner 16 and outer 14 members about the axis X. With reference to Figures 19d-(i) and 19d-(ii), four guide arrangements 600a, 600b, 600c, and 600d are equispaced about the axis X between the inner 16 and outer 14 members, as shown. As can be seen, taking the guide arrangement 600a as an example, each guide arrangement (600n) comprises two spaced apart fins 602a, 604a that are parallel and vertically aligned and which extend or project from the interior wall of the outer member 14. Each guide arrangement (600n) comprises a third fin 606a which is positioned on the exterior wall of the inner member 16 so as to extend between the fins 602a, 604a. Of course, the configuration could be reversed (depending on the specific requirements for a specific project) in which the fins 602a, 604a could extend from the exterior wall of the inner member 16, and the third fin 606a could extend from the interior wall of the outer member 14. As can be seen, the arrangement enables fins 602a, 604a to interact with the third fin 606a for maintaining the desired relative configuration between the inner 16 and outer 14 members about the axis X should it depart from that shown. It will be appreciated that while four guide arrangements are shown, less or more can be used. The skilled reader will appreciated that other arrangements can be realised to achieve the same functionality / purpose.

[0220] The fins described above may be exemplified in the form of lengths of elongate “L” sections, whereby one of the flanges can be used for attachment to the relevant surface of the inner / outer member. Attachment may be by way of any suitable fit-for- purpose means, such as, for example, mechanical / adhesive fastening or any appropriate welding process. The skilled reader would be aware of various ways in which the functionality provided by the fins could be provided (and the types of materials and fastening means appropriate to the present / prevailing context). In the form shown, the fins are formed from steel material (or any suitable grade of steel material appropriate for its intended application and operational environs).

[0221] Forms of guide means considered to provide or improve practical advantage could be those involving minimal or no moving parts (ie. so as to minimise componentry likely to require on-going maintenance / servicing attention when experiencing operational wear / tear, such as those components which would be exposed to corrosive or frictional environments during operation).

[0222] Guide means arrangements configured to provide a passive means of guiding the desired relative movement between the members 14, 16 while avoiding / minimising frictional forces between moving parts could offer substantial advantage. For example, guide means providing water-based bearing functionality (eg. pressurised water caused to operate within constricted regions between moving componentry using pump modules) between the outer 14 and inner 16 members could assist in providing a form of lubricating functionality between corresponding walls of the members 14, 16 and to help ensure concentricity of both members relative to each other about the axis X. The skilled reader would readily appreciate the types of arrangements that could find ready application to present purposes.

[0223] With reference now to Figure 2, the embodiment of the WEC apparatus 10 shown is ballasted. In some embodiments, ballasting may not be required, for example, due to efficiency in design of hydrostatic stability of one or both of the outer 14 and inner 16 members, and / or other components of the WEC apparatus 10.

[0224] For the embodiment shown in Figure 2, both the outer member 14 and the inner member 16 are provided with a primary ballasting means 20A / 20B provided towards respective bottom or foot regions 11A / 11B of each of the vertically extending inner 16 and outer 14 members. In the form shown, the primary ballasting means 20A / 20B is a fixed ballast. In other embodiments, however, at least one of the outer 14 and inner 16 members may comprise the fixed ballast means (20A / 20B). The fixed ballast may be designed so as to be a non-removable ballast. Suitable materials for use as the fixed ballast include, for example (non-exhaustively), high density materials such as steel, Iron, concrete, and lead. The skilled person would readily identify or be aware of suitable ballasting materials.

[0225] Each of the outer 14 and inner 16 members is further provided with at least one secondary ballasting means 22A / 22B comprising at least one chamber that extends through a wall or cavity of the respective members 14, 16. In one form, the secondary ballast means 22A / 22B is configured to contain a soft ballast, such as for example sea water. For the embodiment shown, the secondary ballast means 22A / 22B is not adapted to be adjusted during operation of the WEC apparatus 10 but could be so enabled using appropriate pumping technologies and suitable control systems that are informed, for example, by suitable sensing / monitoring equipment appropriate for real-time operational optimisation purposes (and which could be driven by Al technologies, for example).

[0226] The primary ballasting means 20A / 20B and the secondary ballast means 22A / 22B are designed to ensure a predetermined minimum depth or draft of the WEC apparatus 10 to seek to enhance or ensure stability of the WEC apparatus 10 in a given geographical location and / or for circumstantial (current and / or forecast) sea / environment conditions. A number of considerations influence the ballasting requirements of the WEC apparatus 10. Such factors may include, but are not limited to: targeting incident wave conditions to optimize power production of the WEC apparatus 10; giving consideration to a predetermined or desired Response Amplitude Operator (RAO) of the WEC apparatus; maintaining a positive metacentric height (or measure of the initial static stability of a floating body), maintaining a desired freeboard, such that waves do not rise past a predetermined point at the top of the outer 14 and inner 16 members; maintaining a minimum distance from the bottom or base of the WEC apparatus 10 to the seabed; maintaining integrity of the WEC apparatus 10 during storm events (ie. maximizing storm survivability); limiting vertical movement of the WEC apparatus 10 during maintenance or repair events; and, maintaining integrity of a dynamic sub-sea cable (see feature 34 in Figure 1, and described below). In certain instances, fixed ballast calculation may be based on a combination of one or more of the above factors. The metacentric height of various embodiments of the WEC apparatus 10 may be greater than about 0.5m, or greater than about 1m, or greater than about 1 ,5m, or greater than about 2m, or greater than about 3m, or greater than about 5m, or greater than about 10m.

[0227] Additionally, each of the outer 14 and inner 16 members of the embodiment of the WEC apparatus 10 shown in Figure 2 are provided with at least one respective variable ballasting means 23A / 23B. Broadly, the variable ballast means 23A / 23B may be configured so as to be adjustable, such that the depth or draft of the individual outer 14 and inner 16 members can be adjusted or varied during operation (or otherwise). Generally speaking, the draft of the inner 16 and / or outer 14 members is considered to be related to the hydrodynamic performance and motions of the inner and / or outer members. The size and ballasting requirements of the outer 14 and inner 16 members of the WEC apparatus 10 may be designed according to the requirements of the geographical location of intended operation of the WEC apparatus 10 and / or prevailing (and / or forecasted) sea / weather conditions. In this manner, the range of depths or drafts available by adjusting the variable ballast means may be a function of, for example, a range of target wave periods.

[0228] In some embodiments, the amount of variable ballast means 23A / 23B required may be calculated such that, during operation, one or each of the outer 14 and inner 16 members has a predetermined resonance so that at least one of the outer 14 and inner 16 members resonates in an incident wave regime. In another embodiment, for example, the variable ballast means 23A / 23B of the outer 14 and inner 16 members are adjusted or adjustable such that the members 14, 16 each resonate at different wave frequencies or resonate out-of-phase in the same wave frequency.

[0229] In the arrangement shown in Figure 2, the variable ballasting means 23A / 23B comprises at least one chamber that extends vertically through a wall or cavity of the respective outer 14 and inner 16 members, the at least one chamber being operably connected to a pump system (not shown, but could involve one or multiple pump modules, eg. submersible or bilge pumps) which is configured so as to pump sea water into and out of the relevant chamber(s). The variable ballasting means 23A / 23B may be adapted or configured so as to be adjustable depending on various parameters, such as for example, the incident wave conditions. Figures 3C and 3D show different embodiments of the variable ballasting means 23A / 23B. The variable ballasting means 23A / 23B can be provided as a single chamber, or as multiple chambers.

[0230] The WEC apparatus 10 is designed such that the variable ballasting means 23A / 23B of the respective outer 14 and inner 16 members can be adjusted independently of one another. In this manner, the outer 14 and inner 16 members may be ballasted to different pre-determined depths or drafts based on information related to incident wave frequency, which enables the outer 14 and inner 16 members to resonate at different wave frequencies and in different phases thereby increasing the relative motion between the outer 14 and inner 16 members.

[0231] Typically, in operation of at least one embodiment, the heave motion of the outer 14 and inner 16 members is directly proportional to their respective depth / draft parameters. The depth / draft of the outer 14 and inner 16 members of the WEC apparatus 10 can be adjusted so that each member 14, 16 will have a desired resonant frequency and phase relationship. The ballast of the two members 14, 16 may be adjusted so that (i) at least one member (14, 16) is resonating in any given incident wave regime, (ii) the two members (14, 16) are heaving at different resonant frequencies, or (iii) the two members are heaving out of phase from each other.

[0232] It would be readily understood by the skilled reader that the position and design of the variable ballast means 23A / 23B can be altered or varied based on one or more of the desired or intended operational requirements of the WEC apparatus 10. For example, in use, the variable ballast 23A / 23B may be adjusted by pumping water into and / or out of the relevant containing / holding chamber or cavity.

[0233] In some embodiments, the variable ballasting (23A / 23B) may involve using a compressible fluid (eg. compressed air) to push ballast water held in a ballast tank or chamber out of a valve below the water line. Said valve (or any other valve in fluid communication with the ballast tank or chamber holding the compressed fluid) can be opened (eg. in a selective manner) so as to passively allow water into the relevant ballast tank or chamber as desired. In some embodiments, variable ballast means (23A / 23B) may be configured adjustable for extreme conditions (eg. ‘survival’ conditions) so as to provide or converge the WEC apparatus (10) toward a desired or predetermined optimal draft or freeboard condition of one or both of the outer (14) or inner (16) members, that may be in accordance with technical engineering / considerations.

[0234] In an embodiment, the variable ballast means (23A / 23B) may comprise a first pump (eg. a submersible or bilge pump) is provided inside of a respective ballast tank or chamber of the variable ballast means (23A / 23B) and configured operable for removing water held inside the ballast tank or chamber to external environs when required. In an embodiment, a second pump is provided external of the ballast tank or chamber of the variable ballast means (23A / 23B) and configured operable for pumping water from the external environs into the ballast tank or chamber when required.

[0235] The skilled reader will appreciate that the metacentric height of the WEC apparatus 10 is a function of the displaced volume (centre of buoyancy) and the centre of gravity, and will change every time the ballasting condition is altered. Factors influencing the metacentric height of an embodiment of the WEC apparatus 10 may include any of: the level or degree of fixed ballast (20A / 20B), the level of the variable ballast (23A / 23B), the draft or freeboard condition, volume of water below the water line.

[0236] The WEC apparatus 10 may be designed to have a predetermined Response Amplitude Operator (RAO). The RAO (see here for further information: https: / / www.calqlata.com / productpages / 00081-help.html) may indicate the ratio of the linear motion response and linear incident wave amplitude, and can be used as a statistic or measure of the degree of optimisation or efficiency of the power output of an embodiment of the WEC apparatus (10). The RAO can be used in the design of an embodiment of a WEC apparatus (10) of the present disclosure. In some forms, the RAO of the WEC apparatus 10 is designed or used to optimise power output of a single WEC apparatus or WEC system (involving multiple WEC apparatuses (10)). In certain embodiments, the RAO is at least about 0.2m / m, or at least about 0.5m / m, or at least about 0.8m / m, or least about 1.0m / m, or at least about 1.5 m / m, or at least about 2.0 m / m, or at least about 3.0m / m.

[0237] As noted above, the WEC apparatus 10 is operably connected to at least one Power Take Off (or PTO) module - shown generally in Figures 3A to 3D as reference 21. With reference to Figure 1 and Figure 3A, at least a portion of the PTO module 21 is accommodated, hosted or housed in the outer member 14 and structurally coupled or anchored to or with the inner member 16 by way of a coupling arrangement 29 (described below) which can be or be part of the PTO module 21.

[0238] For the embodiment shown in Figures 3A-3D, the PTO module 21 is provided in the form of a permanent magnetic linear generator in which at least one stationary coil member 26 (eg. formed from copper material) and at least one movable permanent magnet member 28 are accommodated, hosted or housed by the outer member 14. For the embodiment shown, the permanent magnet member 28 is coupled / anchored to or with the inner member 16 by the coupling arrangement 29. In the form shown, each of the coupling arrangements 29 comprise a respective piston member 29-P extending from a topside structure 32 of the inner member 16 and which carries or supports at its distal end, at least one respective permanent magnet member 28 or a stack of multiple permanent magnet members 28. In an embodiment, a number of permanent magnet members 28 may be positioned along the length of the piston 29- P. In the form shown, the piston 29-P is a tube of steel construction configured so as to extend from the topside structure 32 as shown. In this manner, the piston 29-P supports the permanent magnet members 28 within the cavities 24A of the outer member 14 during operation. Alternatively, the piston member 29-P, or a substantial portion of it, comprises or is formed of permanent magnet material.

[0239] In use, the relative vertical motion between the inner 16 and outer 14 members drive the moveable permanent magnet member(s) 28 past their relative stationary coil member(s) 26 thereby converting wave energy into electrical power. As noted above with regard to the ballasting arrangements that are applicable to both of the outer 14 and inner 16 members, the favourable exploitation of hydrodynamic principles in respect of both outer 14 and inner 16 member (as opposed to, or in contrast to, relative moment of just a single member) results in both the outer 14 and inner 16 members being subject to movement which can be harnessed so as to maximise the scope of relative movement between both members 14, 16 for maximising power generation.

[0240] Examples of other suitable types of PTO modules (21) which could be employed include, but are not limited to, switched reluctance linear generators (including, for example, multi translator switched reluctance linear generators, or MSRLG’s and variants), mechanical generators (eg. an example system is shown at URL https: / / www.wetgen.com / PTO_page.htm), hydraulic generators (eg. an example system is shown at URL https: / / www.researchgate.net / figure / Schematic- representation-of-the-hydraulic-PTO-of-a-heaving-wave-energy- converter_fig27_222604679), and pneumatic generators (eg. an example system is shown at URL https: / / www.youtube.com / watch?v=jFJ6s_5-v7E). The skilled reader will appreciate other types of PTO modules or systems that can be employed.

[0241] The permanent magnet linear generator PTO modules (21) are therefore used to convert mechanical energy produced between the relative movement between the outer 14 and inner 16 members (drive by wave / swell kinetics) to electrical energy. For the form shown and described herein, the power conversion components are accommodated, hosted, or housed inside the outer 14 member. In this arrangement, relative linear motion between the members 14, 16 occurs entirely within the outer member 14 as the permanent magnet member 28 is caused to move (or be driven) by the inner member 16 (by way of the coupling arrangement 29) relative to the stationary coil member 26 and converted to electrical energy. In other forms, for example, the relative linear motion between the outer 14 and inner 16 members could be captured by hydraulic or pneumatic equipment and converted to rotary power through fluid pumps and motors connected to power generation equipment. The skilled reader would readily appreciate other arrangements which could be possible to achieve the functionality in the present context. As has been noted, embodiments of the WEC apparatus 10 may be PTO module or system agnostic. Embodiments of the inner 16 and / or outer 14 members of the WEC apparatus 10 of the present disclosure can be configured so as to provide sizeable and / or variable payloads, thereby enabling provision for hosting, accommodating, or housing a large number of different weight combinations and / or loads for carrying various / extra equipment. Put simply, embodiments of the WEC apparatus 10 configured consistent with the present disclosure can offer sufficient onboard capability / capacity for accommodating, hosting, or housing various equipment as might be required for a given application. This enables a wide variety of PTO modules to be used with the core principles of the WEC apparatus of the present disclosure.

[0242] The PTO modules 21 are accommodate, hosted or housed in vertically extending cavities 24A provided in the walls of the outer member 14, as shown in at least Figures 3A and 3B. The vertically extending cavities 24A of the outer member 14 are shown in varying arrangements in Figures 3A to 3D. The lengths of the stationary coil member 26 may be any suitable length considered appropriate for operation. In one embodiment, for example, the stationary coil member 26 may be configured so as to extend vertically substantially the same length of its host housing, and the moving magnet member 28 may be configured so as to be substantially shorter than the length of the stationary coil member (with which it operates during power conversion / generation).

[0243] Some embodiments of the WEC apparatus 10 may comprise multiple PTO modules 21, with each being spaced as appropriate (eg. regularly or irregularly as might be required) about the wall defining the relevant host member 14, 16 (the outer member 14 for the case of the embodiment of the WEC apparatus 10 shown throughout the figures). In one form, the spacing of the PTO modules 21 is to ensure a uniform weight distribution about the relevant host member 14, 16. Accordingly, embodiments of the WEC apparatus 10 may comprise at least two (2) PTO modules, or at least four (4) PTO modules, or at least six (6) PTO modules, or at least eight (8) PTO modules. The skilled reader will appreciate that any number of PTO modules (21) can be used (eg. an even or odd number of PTO modules can be used). The number of PTO modules (21) used may depend on balancing (eg. weight) requirements / distribution around the relevant of the outer / inner members (14, 16), and / or the target rated capacity of an embodiment of the WEC apparatus (10), which could vary, for example, from about 1 MW to about 12MW or more. In one embodiment, the target rated capacity of an embodiment of the WEC apparatus (10) may be about 8MW. In another embodiment, the target rated capacity of an embodiment of the WEC apparatus (10) may be about 3MW.

[0244] It would be readily understood that the arrangement of the PTO module 21 can be reversed, such that the PTO modules 21 are housed on the inner member 16 and coupled / anchored to / with the outer member 14. Additionally, it would be understood that the permanent magnet member 28 could be stationary with one of the members 14, 16 with the coil members 26 configured so as to be moveable and coupled / anchored to or with the opposing or alternate member. Additionally, it would be understood that the WEC apparatus 10 can be adapted to house alternative PTO modules (21).

[0245] The PTO module (21) and power conversion system componentry may include (non- exhaustively) any of the following: pneumatic arrangements, hydraulic arrangements, mechanical linkages, generators, linear generators, linear electrical generators, controllers, electrical equipment, rack / pinion type arrangements. The skilled reader would readily appreciate other types of equipment suitable for use in the present context.

[0246] As noted above for the WEC apparatus, each permanent magnet member 28 is driven by the inner member 16 relative to its respective stationary coil 26 by way of respective coupling arrangements 29. Relative movement between the permanent magnet member 28 within the stationary coil member 26 is facilitated by a linear guide means (not shown) that ensures the movement is translational and aligned vertically. The skilled person would readily appreciate arrangements of linear guides suitable for present purposes.

[0247] During operation, it can be the case that one or more of the PTO modules 21 experience a technical issue causing them to perform below usual operational standards, or to not function at all. For the case of a PTO module 21 experiencing an electrical fault, for example, the affected PTO module 21 can be electrically isolated allowing movement of the relevant permanent magnet member 28 relative to its associated stationary coil member 26 to still occur (albeit, with no power take off from the affected PTO module), allowing the remaining PTO modules 21 of the WEC apparatus 10 to continue operating. In such cases, the WEC apparatus 10 can continue operation (ie. power take off) until the next scheduled service cycle (which may be at a time where ocean swell is scheduled / forecast to be minimal) where the WEC apparatus 10 can be shut down and the inner 16 and outer 14 members mechanically locked while the repair / servicing work takes place. For embodiments where a single WEC apparatus (10) is a ‘corner’ of a larger floating WEC system (eg. a WEC system involving multiple WEC apparatus (10), such as that shown in Figures 4, 8, 10) the same actions occur in the event any of the PTO modules 21 of the (or any) ‘corner’ of the WEC system are compromised.

[0248] Accordingly, in the embodiments shown in the Figures, each respective coupling arrangement 29 is configured so as to enable transfer of drive from the inner member 16 to the permanent magnet member 28 during usual operational conditions by any respective piston 29-P. Depending on how the permanent magnet member 28 is to be associated with the coupling arrangement 29, provision may also be made so as to allow the coupling arrangement 29 to be capable of disabling the transfer of drive between the permanent magnet member 28 and the inner member 16 in the event physical movement of the permanent magnet member 28 becomes compromised or (at worst) prevented, eg. in the event the permanent magnet member 28 stops (or seizes) within its linear guide means. Wthout a means of disabling drive transfer, such an event has the potential to either stifle or, at worst, prevent movement of the inner member 16, therefore risking damage to any of the operational componentry of the WEC apparatus 10. As one example, the coupling arrangement 29 could comprise a form of shear pin coupling configured to limit the peak loads to a predetermined safe value. As the skilled reader would appreciate, the value of shear pin coupling technology is that the shear pin(s) can be configured to shear at predetermined design values thereby physically separating the driving member (eg. the inner member 16) from the driven half of the coupling (eg. the permanent magnet member 28). The skilled reader would be aware of other technologies that could be incorporated for providing equivalent functionality for use with the coupling arrangement 29.

[0249] The PTO modules 21 are housed within their interior / internally formed cavities 24A provided within the wall of the outer member 14 so as to be provided in air and in a maintained atmosphere. In some embodiments, provision may be made so that each PTO module 21 can be easily accessed (eg. using infrastructure such as, for example, stairways, safety ladders, access landings, walkways and / or the like) by an operator for operations and servicing / maintenance activities. The internal cavities 24A can therefore be provisioned with suitable infrastructure (eg. the implementation of platforms, walkways, scaffolding, stairwells etc) so that the appropriate access can be enabled to all required constituent componentry of the PTO modules 21 used in the relevant WEC apparatus 10 (and indeed the WEC apparatus or system 10-S shown in Figures 4 to 7 and the WEC apparatus / system 10-S in Figures 10 and 11, and the structure 80 shown in Figure 8. Access to these internal cavities 24A will be from any above surface portion of the outer member 14. For example, one or more access doors or hatches can be provided within the annular shaped deck or platform portions 27 of the outer member 14 (see Figures 1, 2, 3A and Figure 4) so that personnel can gain access to the PTO modules 21 as required. The skilled reader would readily appreciate other ways in which such access can be achieved for equipment of this nature and for this application / context.

[0250] Of course, analogous provisioning for equipment access requirements can be made in respect of embodiments where the PTO modules 21 are provided accommodated, housed or hosted in the inner member 16.

[0251] With reference to Figure 2, the PTO module 21 is operably attached (attachment not shown) to a PTO system 30 provided on a topside structure 32. In accordance with one embodiment, the topside structure 32 may be any structure which is operably adapted to house the PTO system 30. In certain embodiments, the topside structure 32 is attached to the WEC apparatus 10. In certain embodiments the topside structure 32 is mechanically connected to the inner member 16 or outer member 14. In some embodiments the topside structure 32 is a horizontally extending platform, the topside structure 32 being attached to the inner member 16 of the WEC apparatus 10. For embodiments involving multiple WEC apparatuses (10) arranged as part of a WEC system (like with the embodiments shown in Figures 4 to 8, for example), the structure interconnecting the WEC apparatus (10) may be used to provide support structure for supporting the relevant PTO system 30 equipment.

[0252] The PTO system 30 is adapted / configured in use to convert the energy output of the PTO modules 21 to a usable energy product. The PTO system 30 is operably connected to a dynamic sub-sea cable 34, configured for use in transferring the energy product to an energy distribution means (not shown) and adapted to allow for the constant vertical motion of the WEC apparatus 10 relative to the seabed. The dynamic sub-sea cable 34 may be used to carry suitable network communications technologies enabling remote monitoring / operation of the WEC apparatus 10 in realtime, which monitoring / operation data / information would assist in the on-going automated operation by of suitable modelling to optimise performance at any time for any circumstance. Such data / information (and communications medium) could be used to inform / teach / update any Al technologies used in the ongoing operation of the WEC apparatus 10. Rather than running straight to the sea floor, a portion of the sub-sea cable 34 can be coupled to buoyancy systems that elevate the portion of the cable. The sub-sea cable 34 may then have a curved path, which allows the WEC apparatus 10 to move vertically or horizontally with the waves, current and tides without putting any significant additional tension on the cable.

[0253] The PTO system 30 includes any necessary equipment such as, for example (non- exhaustively) power conditioning equipment, inverter module, transformer module, control equipment, monitoring and measuring devices placed around the WEC apparatus 10, and housed in a suitably configured (ie. of appropriate rati ng / certification) weatherproof enclosure or container (eg. standard shipping containers of suitable size can be used). In one form, the PTO system 30 may be housed in at least one enclosure or container located on a structure or platform attached to a portion of the WEC apparatus 10. In other embodiments, the PTO system 30 may be housed in at least one enclosure or container located in one of the outer 14 or inner 16 members.

[0254] Without being bound by scale testing of various embodiments of the principles of the present disclosure tested to date, a number of geometric relationships or parameters are considered to play a role in the design of the WEC apparatus 10 of the present disclosure.

[0255] In one embodiment, the PTO module 21 is a linear generator produced by Trident Energy Limited (a current general datasheet for such examples can be found here: https: / / www.tridentenergy.co.uk / wp-content / uploads / 2014 / 01 / Trident-Energy-Linear- Generator-Datasheet.pdf). In one form, embodiments of PTO modules (21) of this type can be found to offer advantage because they have the least number of moving parts (eg. no gearboxes), least number of stages in the conversion process (eg. no hoses and / or accumulators etc), and, in many respects, can be the lowest in cost to maintain with increased or superior reliability.

[0256] Embodiments of the WEC apparatus 10 may be PTO module (21) agnostic. Embodiments of the WEC apparatus 10 of the present disclosure can be configured so as to provide sizeable and / or variable payloads, thereby enabling provision for hosting, accommodating, or housing a large or increased number of different weight combinations and / or loads for carrying various / extra equipment - which includes componentry of a PTO module or system. This enables a wide variety of PTO modules to be used with the core principles of the WEC apparatus of the present disclosure.

[0257] In accordance with a first geometric relationship, a ratio between the draft of the outer member 14 to the dimension defining the outer most diameter of the outer member 14, is about 3:1 or less. Embodiments of the WEC apparatus (10) could be developed where this first geometric relationship is between a range of from about 1 :1 to about 3:1 , or less than 1 :1. For one design consideration, the draft parameter of the outer member 14 is informed by the depth of water of the intended location of operation, and then fixed thereby driving the geometric configuration of the outer member 14.

[0258] In accordance with a second geometric relationship, a ratio between the cross- sectional area of the outer 14 and inner 16 members is about 0.5:0.5, where 1 .0 represents 100 percent of the cross-sectional area enclosed by the outer diameter of the outer member 14. Embodiments of the WEC apparatus (10) could be developed where this second geometric relationship varies from about 0.5:0.5 to about 0.7:0.3 or to about 0.3:0.7, or from about 0.7:0.3 to about 0.3:0.7. In one embodiment, the outside diameter of the outer member 14 is about 11 m, and the outer diameter of the inner member 16 is about 7.5m. In certain embodiments, the diameter of the outer 14 and inner 16 members is determined by the wave length of the target incident waves.

[0259] With reference again to Figure 1, the WEC apparatus 10 is attached to a mooring system 36 which is configured so as to restrict horizontal movement of the WEC apparatus 10, whilst enabling the vertical motion of the outer 14 and inner 16 members. Known mooring systems 36 can be used, for example, 3 to 6 point spread mooring systems would be suitable. Embodiments of the WEC apparatus (10) may also be connected to mooring systems using semi-taut or tension leg moorings. Embodiments of the WEC apparatus (10) may also be connected to mooring systems using shared anchors of other adjacent WEC apparatuses. In some arrangements, use of a shared anchor type mooring system could allow for multiple moorings for different embodiments of the WEC apparatuses (10). The mooring lines can be conventional catenary-shaped lines composed of a combination of chain, wire ropes and drag-embedment anchors. The mooring lines may be composed of taut polyester sections, and also include clump weights (heavy masses suspended to sections of the mooring system). In various embodiments, multiple or arrays of embodiments of WEC apparatus 10 of the present disclosure, as well as embodiments where multiple WEC apparatus are used to form broader (floating) energy conversion apparatus or systems 10-S (eg. using two, three, four or more WEC apparatus of the present disclosure), are connected together via shared mooring lines or systems.

[0260] The PTO system 30 further comprises a control system (not shown). The control system may be configured so that any of the variable elements of the WEC apparatus 10 can be adjusted so as to optimise performance of the WEC apparatus 10 based on measurements taken from measuring / sensing devices placed around any of the constituent componentry of the WEC apparatus 10. Variable elements controlled by the control system may include, but are not limited to, PTO module(s) / system(s) damping and stiffness, ballast configuration and / or depth or draft of the WEC apparatus 10, and / or constituent componentry of the mooring system 36 (eg. mooring line length). Measurements are taken around the WEC apparatus 10 monitoring changes in various parameters such as, for example, displacement, velocity, acceleration, pressure, wave height and wave period, power production and output, geographical / spatial positioning. The control system may be configured so as to adjust the variable element(s) of the WEC apparatus 10 so as to optimize survivability in extreme wave or weather events.

[0261] It will be appreciated that modem artificial intelligence or Al technologies could be employed to enable sustainable autonomous operation and / or optimisation of the performance of the WEC apparatus 10 (and, indeed, a system comprising a collection of multiple WEC apparatuses, as described below) in real-time or otherwise.

[0262] Generally, operation of the WEC apparatus 10 is arranged in accordance with a number of modes of operation. Put another way, these modes of operation may exist across a spectrum of operation.

[0263] In one mode of operation, or at one end of the spectrum of operation, the WEC apparatus 10 is configured so that the outer 14 and inner 16 members are locked (hereinafter, ‘locked’ mode of operation) together so as to prevent relative motion therebetween. This mode of operation generally serves as a ‘survival’ configuration in the event of extreme conditions (eg. storm conditions involving high winds and large sea states that could damage constituent equipment of the WEC apparatus 10 if left in operation) so that risk of prospective damage to the constituent componentry is, to the extent possible, minimised or prevented. As no relative motion is allowed to occur between the outer 14 and inner 16 members, power generation or conversion capability is disabled (in a 100 percent dampened condition or state between the outer 14 and inner 16 members) in favour of protecting the integrity of the equipment from damage. Suitable (releasable) locking means or arrangements include (non- exhaustively) electrical locking systems, mechanical locking systems, hydraulic locking systems or pneumatic locking systems. The skilled reader will appreciate other forms of locking arrangements suitable for use in the present context / application. One embodiment of a releasable locking mechanism 300 is shown in Figures 13 and 14 (general cross section view shown). With reference to Figure 13, two releasable locking modules 300a and 300b (collectively, locking mechanism 300) are shown positioned on an upper surface of the outer member 14, and about the axis X. Each locking modules 300a, 300b comprises a respective body 304 that comprises an axial passage or cavity 306 that accommodates or houses a respective pin 308a, 308b. In operation of the releasable locking mechanism 300, the pin 308 is movable within the axial passage or cavity 306 so as to be placed in disengaged or engaged conditions with the inner member 16, as will be described.

[0264] As seen in Figures 13 and 14, the outer wall of the inner member 16 is provided with passages or cavities 312a and 312b, each of which are configured so as to receive respective pins 308a, 308b of the releasable locking modules 300a, 300b. The opening of each passage / cavity 312a, 312b is positioned so that the respective axis of the passage / cavity 312a, 312b registers or is coaxial with the axis of the corresponding passage / cavities 306a, 306b when the inner 16 and outer 14 members are at the desired relative position for locking. This enables the relevant pin 308a, 308b to be translated from the disengaged condition (shown in Figure 13) to the engaged condition (shown in Figure 14) where a portion of the pin enters the relevant passage / cavity 312a, 312b thereby mechanically locking the inner 16 and the outer 14 members together at the desired relative position. For the embodiment shown, the relative positioning of the inner 16 and outer 14 members is about 2m between the upper surface of the outer member 14 and the underside of the topside structure 32 (eg. about enough height for maintenance personnel to move about the top of the outer member 14).

[0265] Two releasable locking modules 300a, 300b are shown for explanative purposes, however, the releasable locking mechanism 300 may have any number of locking modules (300a, 300b) as required for a given WEC apparatus design, and is not limited to that shown in Figures 13 and 14. For example, three of four releasable locking mechanisms may be equispaced about the axis X.

[0266] In another mode of operation, the WEC apparatus 10 operates so that relative motion between the outer 14 and inner 16 members is unrestrained allowing or enabling entirely free relative movement between both members 14, 16. In this mode of operation, the members 14, 16 are allowed to move freely relative to each other in an unrestrained manner with no power take off occurring thereby having a minimal dampening state or condition between the members 14, 16.

[0267] In further mode of operation, the WEC apparatus 10 operates in a mode where the PTO module 21 is damped to a maximum level thereby constraining, to the extent possible / available using the PTO module 21, relative movement between the inner 16 and outer 14 members. In this mode of operation, relative movement the members 14, 16 is restrained with no power take off occurring.

[0268] Between the undampened and damped modes of operation, power generation (eg. power take off) occurs commensurately in accordance with the level of dampened (or power take off) state or condition.

[0269] In order to protect the apparatus from damage in situations where maximum stroke of the relative movement between the inner 14 and outer 16 members is reached, an end stop arrangement 320 is provided. With reference to Figures 15 to 17 (general cross section view shown) end stop elements 320a, 320b are positioned atop the upper surface of the outer member 14 about the axis X as shown. The end stop elements 320a, 320b are of an energy absorbing construction such as, for example, a rubber fender (eg. such as those available from Yokohama Corporation). The skilled reader will appreciate that other ways in which end stop protection can be enabled are possible. The skilled reader would also be aware of the types of rubber substrates and construction that the end stop elements 320a, 320b can be formed from so as to be fit for purpose.

[0270] Two end stop elements 320a, 320b are shown for explanative purposes. The end stop arrangement may have any number of end stop elements as required for a given WEC apparatus design, and is not limited to that shown in Figures 15 to 17. For example, three or four end stop elements may be equispaced about the axis X. The positioning and configuration of the end stop arrangement 300 may be designed as required so that sufficient clearance exists between the upper surface of the outer member 14 and the underside of the topside structure 32 as is required, for example, for sufficient distance or height to allow maintenance personnel to move about the upper portion of the outer member 14 when the end stop arrangement 320 has been fully engaged by the topside structure 32 (ie. as shown in Figure 17).

[0271] Some types of PTO modules or systems either available now or developed in the future may not require end stops in which case end stops are not needed.

[0272] With reference to Figures 4-7, three WEC apparatus (identified as, 10A, 10B, and 10C) that are each arranged consistent with the WEC apparatus 10 described above are used to form a higher power generation capable WEC apparatus or system 10-S (hereinafter, WEC system 10-S). Like reference numerals used in respect of the WEC apparatus 10 are retained for ease of description. It will therefore be appreciated that any number of WEC apparatus 10 can be used to form such a WEC system 10-S so as to increase power generation capacity / capability. Each WEC apparatus 10 may represent a ‘corner’ of the WEC system 10-S structure. For the embodiment shown in Figures 4-7, the WEC apparatuses 10A, 10B, 10C are arranged in a triangular form by way of an interconnecting assembly 100. It will be appreciated that multiple WEC apparatuses can be arranged in any appropriate shape or form (eg. polygonal shape / form) keeping in mind compliance with appropriate hydrodynamic stability considerations (as will be described below).

[0273] The interconnecting assembly 100 comprises an assembly of interconnecting elements 110A-110I, some of which are above water (eg. interconnecting elements 110A, 110D, and 110G, or collectively, 110-AW) and below water (eg. interconnecting elements 110B, 110C, 110E, 110F, 110H, 1101, or collectively, 110- BW). The above water interconnecting elements 110-AW may each provide or support respective walkways 112A, 112B, 112C, and 112D (and associated support structures) enabling access between each of the WEC apparatuses 10A, 10B, 10C. Above water walkways 112B, 112C, 112D, help provide support for a deck / platform D atop which various equipment and electrical cabling can be supported. Suitable support structure is provided to support a helicopter landing / take-off pad H (which may or may not be present) from an outer facing region of the outer member 14 of the WEC apparatus 10A. All interconnecting elements 110 of the interconnecting assembly 100 are designed / engineered so as to be structurally competent and fit for purpose. Materials are selected so as to be suitable for the present application.

[0274] The WEC system 10-S may be semi-submerged insofar as, in use, it defines a submerged portion, and a portion that, in use, is located above the surface of the body of water in which it is deployed. In an embodiment, the rigid connectors or interconnecting elements 110A-110I interconnecting at least two WEC apparatuses together are submerged, and comprise one or more tanks or chambers that are operable for use in providing ballast or buoyancy to for ballasting the WEC system 10-S to different drafts or depths.

[0275] In an embodiment, the rigid connectors or interconnecting elements 110A-110I interconnecting at least two WEC apparatuses together are submerged, and comprise one or more holes or apertures enabling the rigid connector to be flooded. Alternatively, the rigid connectors could be sealed so they are always full of air.

[0276] Different geometries (eg. lengths, diameters, dimensions, forms / configurations) of the interconnecting elements 110-AW and 110-BW are possible for any configuration or arrangement of multiple WEC apparatuses (10) which forms a WEC system 10-S. Furthermore, different geometries (eg. lengths, diameters) of the respective outer 14 and / or inner 16 members of respective WEC apparatuses (10) are possible.

[0277] The WEC system 10-S is attached to a mooring system involving mooring lines 36 which is configured so as to restrict horizontal movement of the WEC apparatuses 10A, 10B, 10C, whilst enabling the vertical motion of the respective outer 14 and inner 16 members. The PTO system 30 of the WEC system 10-S is operably connected to or with a dynamic sub-sea cable 34, configured for use in transferring the energy product to an energy distribution means (not shown) and adapted to allow for the constant vertical motion of the WEC system 10-S relative to the seabed.

[0278] The mooring lines 36 are generally symmetrical in arrangement and number used (eg. if two mooring lines are used per constituent WEC apparatus (10), then six mooring lines in total would be used). However, the mooring lines 36 configuration could be asymmetric due to waves coming from a limited range of directions, unlike wind which can be variable about a 360 degree scope in possible direction.

[0279] In various embodiments as might be needed, one or more of the below water interconnecting elements 110-BW could comprise internal tanks or chambers that comprise fixed or soft ballast. In one form, such internal tanks / chambers could be floodable (selectively or otherwise) with sea water should additional ballasting be required. Provision could be made for one or more of the internal tanks or chambers to serve as buoyancy chambers filled with a suitable compressible gas. The internal tanks or chambers of the below water brace elements 110-BW could be arranged into multiple internal compartments on an axially or radially arranged basis relative to the longitudinal axis of a respective interconnecting element. Accordingly, in operation, for example, provision could be made so that one or more of the internal tanks or chambers can be selectively floodable with sea water when circumstances require, following which the sea water can be displaced from the relevant tanks / chambers using suitable pumping means so as to provide buoyancy. In such arrangements, flexible bladders could be provided in the tanks / chambers to / from which a gas is transferable for enabling sea water to be introduced or displaced from the relevant tank / chamber as required.

[0280] Part water filled tanks / chambers can be disadvantageous unless ‘sloshing’ of the water (caused by movement of the WEC system 10-S due to sea state conditions) can be mitigated or avoided. In this regard, any of the tanks / chambers can be arranged having internal baffle arrangements that can serve to dampen or control the movement of water within the tanks / chambers in a passive or active manner in order to attempt to converge toward a desired (ie. improved or optimised) hydrodynamic ballasting or buoyancy condition in view of the prevailing environmental circumstances (eg. sea / weather situation). Examples of passive control of water movement within the tanks / chambers may involve the use of static baffle structures which may hold and release water as a function of the rolling / pitching motion of the WEC system 10-S structure. Examples of active control of movement may involve use of controllable pumping modules operable with fluid paths arranged so as to controllably direct movement of water within or around specific tanks / chambers of interconnecting element 110-BW in response to rolling / pitching motions as might be detected or sensed by a suitably configured sensing / monitoring system. Active transfer of ballast water may be substantially autonomous based on programmed response instructions or by way of Al technologies.

[0281] The below water interconnecting elements 110-BW could be arranged so as to be in fluid communication with the ballast tanks / chambers of respective outer members 14 of one or more WEC apparatus 10A, 10B, 10C of the WEC system 10-S.

[0282] A further geometric parameter can also have value in the design of WEC systems (10-S) involving multiple WEC apparatuses 10. In this regard, a distance between adjacently disposed WEC apparatuses 10 can assist in conferring a number of advantages, such as for example, the hydrodynamic stability of the overall resulting WEC system 10-S structure and the space available for various operational infrastructure, resources and equipment. Generally, operational efficiency of a WEC system 10-S is proportional to the number of WEC apparatus 10 involved in the WEC system, as well as the number of PTO modules 21 included with each constituent WEC apparatus (10). In certain embodiments, for example, multiple WEC apparatus 10 can be arranged in various polygonal shapes / arrangements. As such, the distance between adjacent WEC apparatus 10 can offer improvement in hydrodynamic stability as longer distances between comers (ie. with each corner providing a WEC apparatus (10), as shown in Figure 4) can assist in providing enhanced hydrodynamic stability. Thus, increases in the distance between WEC apparatus (10) translates to opportunity to procure stability as well as space for providing other forms of infrastructure which can be used, for example, in the provision of operational utilities (eg. helicopter pad, maintenance stores, batteries, solar panels, solar arrays, additional energy harvesting / conversion equipment, accommodation, offices, etc).

[0283] However, the distance between adjacently disposed WEC apparatuses 10 is also informed by financial considerations in that the area of the footprint of the WEC system 10-S is usually charged (purchased or leased) on a per acreage basis).

[0284] Operation of the WEC system 10-S can be seen schematically in Figure 7 where an elevation view of one side of the WEC system 10-S is shown with WEC apparatus 10A and 10B experiencing an incident wave regime. For the cycle of the incident wave regime shown, the WEC apparatus 10A is experiencing a peak P of the wave cycle, and the WEC apparatus 10B is experiencing a trough T of the wave cycle. As can be seen, when experiencing the peak P, the respective inner member 14 of the WEC apparatus 10A is caused to rise according to its (prescribed) buoyancy characteristics as the peak P approaches. At this time, the respective inner member 14 of the WEC apparatus 10B, having just experienced the peak P, falls according to its (prescribed) buoyancy characteristics as the trough T approaches. As noted above, this relative movement between the respective outer 14 and inner 16 members continues in accordance with the incident wave regime and harnessed for generating power. As noted above, increases in the scope of relative movement can be achieved when respective outer 14 members also rise and fall according to their (prescribed) buoyancy characteristics (as opposed to the outer member 14 being stationary and only the inner member 16 being movable with the incident wave regime).

[0285] Sensor modules placed on or about embodiments of the WEC apparatus 10 and the WEC system 10-S may be operable with a control system to actively control the floating condition (eg. inclination) of the relevant structure as might be required for a given incident wave regime and / or weather conditions. The sensor modules may include any suitable sensor device that can sense the physical state and / or orientation of the WEC apparatus / system structures and / or the local wind and sea state characteristics. Such sensors may include any of the following (subsea specific or otherwise) non-exhaustively: pressure sensors, proximity sensors, inclinometers, rotation sensors, wire length measurement sensors, gyroscopic sensors, inertial measurement sensors, position measuring sensors, accelerometers, geographical / spatial positioning sensors, sensors for measuring / determining displacement, depth sensors. LiDAR and laser radar technologies could be used, individually or in combination, to generate an indication of long range weather detection (which could, for example, indicate swell size and direction). The skilled reader will be aware of other types of sensors or sensor modules that could be used for enabling control systems to be developed for operating embodiments of the WEC apparatus of the principles of the present disclosure. Furthermore, not all of the latter mentioned sensors may be required, only what is needed for operation of a WEC apparatus (consistent with the present disclosure) for a given application.

[0286] Data from any of the above noted sensor modules can be processed (using a suitable control system, for example) for the purposes of determining and managing various response actions to occur, including, for example, enabling active ballasting of the WEC apparatus / system structure, and / or enabling measures regarding the PTO modules / system to be taken (eg. protection measures). The skilled reader would appreciate various actions that could be enabled using sensing means capable of monitoring various characteristics of the WEC apparatus / system structures and local environmental conditions. Al technologies may be used to facilitate operational efficiencies.

[0287] In some embodiments, a control system (potentially consisting of multiple subcontrol systems) may be used (and configured to draw upon any sensed data of any of the sensors noted herein) to actively manage the ballasting systems so as to maintain a desired level of floating alignment (and maintain the correct draft of the outer member 14 and the inner member 16 such that the WEC apparatus (10 or WEC system 10-S) resonates or does not resonate) of the WEC apparatus (10) or WEC system (10-S) using the sensor information. The control system may also be used to ensure the survivability of the WEC apparatus / system during storm events using information from any of the sensors, and for protecting the PTO modules / system. Suitable sensors may include alignment sensors for detecting movement in pitch and roll freedoms. Any undesired alignment in pitch and roll freedoms may be part of an alarm system which may trigger active ballasting (using suitable pumping arrangements and / or ballast volume sensors) to seek to maintain a desired level of floating alignment of the WEC apparatus or system (which may, by default, involve each ‘corner’ of the WEC system (10-S) holding equal volumes of ballasting water). It will be appreciated that modem artificial intelligence or Al technologies could be employed to enable sustainable autonomous operation and / or optimisation of the performance of the control system. In one embodiment, for example, the control system is configured so as to be operable for determining whether or not water should be pumped in or out of any of the inner / outer members of the WEC apparatus 10 that are part of the broader WEC system 10-S. Generally speaking, embodiments of this control system can be used for ‘survival’ conditions when there is a storm, however, as an operational function day-to-day, it can be used for keeping each of the WEC apparatus 10 (eg. 10A / B / C) that are part of the broader WEC system 10-S resonating with the changing sea conditions.

[0288] In some embodiments, a control system (potentially consisting of multiple subcontrol systems) may be configured (and configured to draw upon any sensed data of the sensors noted herein) and operably linked with the PTO modules (21) or PTO system (30) so as to vary the operation of the PTO module / system by changing the power generation capabilities and resistance on information received from forward facing sensors mounted on the seabed and / or on the WEC apparatus (10) structure (eg. gyroscopes, inclination sensors, fan beam, pressure sensors etc). The sensors may be configured for use in predicting the nature and characteristics of incoming waves (eg. wave height, wave period, wave direction, amongst other parameters). With this information, the control system can be configured so as to adjust the operational characteristics of the PTO modules (21) or system (30) to suit for increasing or maximising power absorption, conversion and electricity production of the WEC apparatus (10) or a WEC system (10-S) having multiple WEC apparatuses. As noted above, it will be appreciated that modem artificial intelligence or Al technologies could be employed to enable sustainable autonomous operation and / or optimisation of the performance of the control system. In one embodiment, for example, this control system can be used to measure or predict the incoming wave characteristics which then inform the setting of the PTO characteristics, eg. damping, resistance etc, to increase or maximise power capture, absorption, conversion and generation.

[0289] In some embodiments of the WEC system (10-S) the inner (16) members may be set at different depths of drafts for optimisation of production / generation of electricity. In some embodiments, the one or more of the outer members (14) of the system (10-S) may be maintained at a generally level floating alignment in which pitch / roll sensors may be used to monitor this condition (on a regular or irregular basis) and / or to trigger active ballasting if required.

[0290] Accordingly, in one design work flow, a consideration in the design of any WEC system (10-S) is optimising the number of PTO modules (21) for inclusion in a constituent WEC apparatus (10), optimising the number of WEC apparatuses (10) used, and determining a suitable layout configuration according to which the WEC apparatus (10) can be arranged that seeks to maximise power generation and hydrodynamic stability while minimising the maximum area or footprint that the WEC system (10-S) structure will occupy.

[0291] Various design parameters have been the subject of parametric testing to explore geometries which can lead to power efficiency. The general configuration shown in Figure 1 (for a single WEC apparatus 10) has been the subject of numerical modelling efforts. This configuration contains two bodies with two modes, in which one mode is a generalised mode. In an example form for numerical modelling purposes, the following base line dimensions were used: outer member 14 diameter = 11 m; outer member 14 draft = 33m; inner member 16 diameter = 7.5m; inner member 16 draft = 38m.

[0292] The general configuration shown in Figure 4 has also been the subject of numerical modelling efforts for comparison against the embodiment above. This configuration contains a total of four bodies and nine modes, in which three modes are generalised modes.

[0293] Using hydrodynamic theory (ie. equations of motion, which would be well known to the skilled reader) the hypothetical performance and motions of each configuration can be modelled. Each of the principal dimensions can be varied (while keeping the baseline values for the remainder) and their sensitivity tested in terms of its impact on power efficiency.

[0294] Very generally, and without being bound by theory and the inherent limitations of the numerical testing carried out, the draft of the inner 16 and / or outer 14 members is considered to be related to the hydrodynamic performance and motions of the inner and / or outer members.

[0295] For a single WEC system (10), increases in the inner member 16 draft and the diameter of the outer member 14 (to a point) demonstrated a correspondence toward an increase in power generation.

[0296] For a three ‘cornered’ WEC system (10-S), increases in the inner member 16 draft and the diameter of the outer member 14 (to a point) demonstrated a correspondence toward an increase in power generation (this finding aligned with that observed from above).

[0297] For a three ‘cornered’ WEC system (10-S), the result of varying (particularly, decreasing) the distance between two WEC apparatus of the WEC system (10-S) did not demonstrate a significant change in terms of power generation.

[0298] It will be understood by the skilled reader that any dimensions presented herein are not limiting. Such dimensions are provided as examples only in order to provide a sense of prospective scale of various embodiments of the WEC apparatus and systems and for providing context for numerical modelling purposes in order to understand the sensitivities of the various physical attributes of the overall structure to power generation for design / optimisation purposes. It will be appreciated that such dimensions may vary depending on various factors, including, among others, the location and environs in which an embodiment of a WEC apparatus / system consistent with the present disclosure is to be installed. The results of the above parametric analysis can be used for cost assessment purposes. Of course, the skilled reader will appreciate that other cost considerations will also inform any design / configuration.

[0299] As noted above, arrangements of the WEC apparatus (10) when forming a WEC system (10-S) can provide benefit in utilising above water portions of the structure used to connect the relevant constituent WEC apparatuses forming the WEC system. The above water portions of the interconnecting assembly (100) can provide support for platform or deck structures which can be engineered to support a diverse range of equipment. Such equipment can include one or more arrays of solar panels for use in generating electrical power for contributing to the output from the WEC system (10-S) or for the running of any operational equipment, including, non- exhaustively: communication systems (internal / external of the WEC system), monitoring systems, control systems, ballasting pumping modules (eg. for pumping ballast in / out of ballast chambers of respective WEC apparatus (10) of the WEC system (10-S) in order to change or adjust natural frequency as might be required), accommodation / office utilities, maintenance repair stores (which could be housed in standard shipping containers supported by above water platform / deck structures), auxiliary / emergency power supplies (eg. diesel generator(s), battery storage arrays (eg. charged by solar arrays supported by the WEC system 10-S for use as auxiliary and / or emergency power supplies, and or for supply of electrical power to the subsea cable 34 providing the option of storage as well as direct supply / export to an electrical distribution means remote of the facility), hydrogen generating equipment or associated product export equipment, tidal or current driven generator, chemical storage, unmanned aerial vehicle take-off / landing infrastructure, autonomous underwater vehicle docking / recharging infrastructure. The skilled reader would readily appreciate the types of equipment that could be beneficial for provision on WEC systems (10-S). In one sense, for example, equipment ordinarily provided on offshore located oil / gas structures could find application on contemplated WEC systems (10-S).

[0300] Stored electrical energy may be made available for use in recharging battery stores of passing seagoing vessels (eg. merchant / defence vessels, submarines etc), as well as underwater or surface autonomous / remote operated vehicles, autonomous / remote operated aerial drones (eg. vertical take-off landing, VTOL capability, multi-rotor type aerial drones).

[0301] Above water space provided by interconnecting elements 110-AW of a WEC system (10-S) could also be used to support one or more alternate energy generation technologies (eg. a wind turbine technology supported by the WEC system (10-S) shown in Figure 8). For example, tidal or current driven generator, hydrogen generation (via electrolysis of the sea water) technology may be provided for use in enabling the WEC system (10-S) to act as a refuelling means for seagoing vessels (eg. merchant / defence vessels, submarines etc), or ammonia generating equipment.

[0302] Battery modules / arrays for electrical energy storage (whether generated via solar or operation of each corner) can be provided on any aspect of the above water structure (atop platform / deck structures) using any suitable housing / enclosures, such as, for example, repurposed standard shipping containers atop a deck structure above water. Battery modules / arrays could also be placed in any of the ballast tank / chambers of constituent WEC apparatus (10) forming the WEC system (10-S), including any of the interior tanks / chambers provided with any of the above or below water interconnecting elements 110 used to connect the WEC apparatus (or ‘corners’) together.

[0303] Various optimisations of the principles of the WEC apparatus 10 of the present disclosure are also the subject of development. With reference to Figures 9 and 12a, a sponson structure 140 may be attached to an outer member 14 of a WEC apparatus 10 and positioned so as to be submerged at or below its waterline. A sponson structure 140 is configured of a suitable geometry so that, when in use (and to the extent possible in prevailing sea conditions), its presence seeks to generate waves from the WEC apparatus 10 which increases the interaction of the WEC apparatus with the incident wave regime, and produces a radiating counter wave which promotes the increase of capture width. Sponsons can be fabricated as required and welded on to the relevant outer member 14.

[0304] Another avenue of optimisation is also possible. With reference to Figures 12b and 12c, parts of the underwater structure of a WEC apparatus (10) or larger / composite WEC system (10-S) may be configured so as to carry heave plates HP (see should an operational situation arise where advantage can be gained). In general, heave plates HP operate to add additional mass to minimise motion so can be disadvantageous if used in conditions where relative motion between the outer 14 and inner 16 members needs to be maximised. However, in certain conditions, the presence of heave plates HP may find advantage when the motion of one or more WEC apparatuses (10) needs to be minimised, for example, in the case of extreme sea states where the risk of damage may be considered high. In such cases, heave plates HP could be designed to be carried or hosted by parts of the WEC system (10-S) structure so that undesirable motions (those potentially causing damage to operational componentry) can be sought to be minimised. In Figure 12b, the heave plate HP is carried at the submerged distal end of the outer member 14. Figure 12c shows the heave plate HP being carried at the submerged distal end of the inner member 16.

[0305] In accordance with an embodiment of a further aspect of the present disclosure, and with reference to Figure 8, there is provided another embodiment of a floating, semi submergible support structure, generally indicated by the numeral 80, comprising three wave energy conversion (WEC) apparatus 10A, 10B, 10C, connected together via three rigid connectors in the form of cross members 82A, 82B that emanate from a central hub 84. The structure 80 may provide a wave energy conversion (WEC) system. Inner members 16A, 16B can be seen projecting from the lower ends of WEC apparatus 10A, 10B.

[0306] Extending vertically from the central hub 84 is a support 86 for a wind turbine 88. The floating support structure 80 is tethered to the see bed via lines 90A, 90B and 90C attached to respective WEC apparatus 10A, 10B and 10C.

[0307] Each of WEC apparatus 10A-10C operate as per the description above in relation to the WEC apparatus 10 described above.

[0308] Figures 10 (perspective view) and 11 (elevation view) show a further embodiment 10-S of a three ‘cornered’ WEC system (each WEC apparatus (10) being identified as, 10A, 10B, and 10C) that are each arranged generally consistent with the WEC system 10-S described above with reference to Figures 4-7. Like references numerals used in respect of the WEC system 10-S are retained for ease of description. It will be seen that Figures 10 and 11 show a simplified version of that shown in Figures 4-7. As the skilled reader will be aware, any number of comers and power take off PTO modules could be employed.

[0309] As seen, the embodiment of the WEC system 10-S shown in Figures 10 and 11 comprises an outer member (14A / B / C) and an inner member (16A / B / C). The inner members (16A / B / C) are configured to move in response to an incident wave regime which, when in use, relative motion between the outer members (14) and the inner members (16) is used to generate a first electrical power or energy product.

[0310] The WEC system 10-S shown in Figures 10 and 11 further comprises a solar harvesting means or system 500 (comprising an array of solar panels 500A, B, C, ... etc - collectively, array of solar panels 500) supported by the apparatus 10-S for, when in use, generating a second electrical power or energy product. In this arrangement, the first and / or second electrical power are distributed from the system 10-S to, for example, an energy distribution means such as an electrical grid (that is remote of the WEC system 10-S). It will be appreciated that the WEC system 10-S shown in Figures 10 and 11 represents a generally small-scale embodiment - where a small number of solar panels are used. It will be appreciated that embodiments can be developed where significantly more solar panels will be employed. Thus, the embodiment shown in Figures 10 and 11 is not be seen as limiting the scale of the solar harvesting means / system that can be used.

[0311] The array of solar panels 500 are supported by a structure 485, such as a roof-frame or canopy-frame like structure shown, that is configured so as to cover a portion of the above water structure of the WEC system 10-S. In this manner, a hybrid energy conversion apparatus can be arranged which operates to harvest / collect solar energy and wave energy for supply of the relevant electrical power (having been converted etc) back to land by way of, for example, a subsea cable 34 (not shown but implied, shown in Figures 1 and 4). Multiple cables could be used to distribute (using a distribution means, such as a subsea cable etc) to a land based electrical grid infrastructure.

[0312] As the skilled reader would be aware, technology associated with the control, operation, and harvesting of solar energy using photovoltaic cells can be employed in order to operate this aspect of the hybrid energy conversion apparatus. The control operation of the relevant PTO modules (21) of the respective WEC apparatus (10A / B / C) can be part of a first circuit which collects and stores electrical energy for transfer using one or more subsea cables (34). Likewise for the solar array 500 as regards a second circuit. Both first and second circuits may be communicable with an onboard electrical storage means (eg. a battery or array of batteries - not shown) so that electrical energy from the PTO modules 21 and the solar panels 500 can be stored awaiting distribution via the subsea cable 34 or can be dispatched directly into the subsea cable 34 for export bypassing the storage if its most expedient to do so. The componentry required for operation would be well known to the skilled reader.

[0313] Each of the first, second circuits can be configured so as to supply respective energy products to the electrical storage means, or supply direct to the subsea cable 34. In this manner, each of the first (generated via the PTO module(s) 21) or second (generated via the solar harvesting means / system 500) energy products can be either supplied direct to the energy distribution means via the subsea cable 34, or, to the electrical storage means / module as may be required. Accordingly, any of the generated electrical power may go direct to the export subsea power cable 34, or may get to the export subsea power cable via the electrical storage means / module.

[0314] The roof-frame or canopy-frame structure 485 may comprise any structural configuration of structural or load bearing capable members for supporting the solar array 500 above the WEC system 10-S. Any appropriate configuration of suitable structural capacity could be developed as required for a given size and capacity solar array 500 configuration.

[0315] It will be appreciated that other forms of renewable energy harvesting technologies could also be employed and supported by the WEC system 10-S.

[0316] The floating support 80 is configured to support a second apparatus. In certain embodiments, the second apparatus could be any apparatus or equipment which could be any of the following (non-exhaustively): a platform, a wind turbine, water desalination equipment, tidal or current driven generator, hydrogen or ammonia generating equipment or associated product export facilities. The skilled reader will appreciate other types of apparatus or equipment that could provide convenience or utility in the context of the present disclosure.

[0317] As has been noted above, embodiments of the WEC apparatus 10 may be PTO module or system agnostic. In this manner, the inner 16 and / or outer 14 members of the WEC apparatus of the present disclosure can be configured so as to provide sizeable and / or variable payloads, thereby enabling provision for hosting, accommodating, or housing a large number of componentry of a wide range of PTO systems or modules. Figures 20 to 22 serve to illustrate conceptual examples of how different types of PTO modules or systems can be integrated with the inner 16 and outer 14 members.

[0318] Figure 20 shows a schematic diagram of an embodiment of a single WEC apparatus 10 arranged consistent with the present disclosure, using a double acting hydraulic PTO module arrangement. Extending from the topside structure 32 (of the inner member 16) are a plurality (only 1 shown) of pistons 29-P which move within a hydraulic fluid HF contained within the cavity 24A (formed within the outer member 14) which serves as a hydraulic cylinder. Each piston 29-P terminates with a piston head 29-H. The movement of the piston 29 is by way of the inner member 16 moving in response to the incident wave regime. The hydraulic PTO module is operable with a PTO system 30 located on the exterior side of the outer member 14. The PTO system 30 comprises the relevant control manifold 400 (which is in fluid communication with the hydraulic fluid HF on both sides of the piston head 29-H), low pressure reservoir 402 and high pressure accumulator 404, motor 406 (which is driven by the hydraulic cylinder), and generator module 408 which is in operable communication with the motor 406. Hydraulic fluid drives the motor 406 which then drives the generator. Upward and downward movement of the piston 29-P generates power.

[0319] Figure 21 shows a schematic diagram of an embodiment of a single WEC apparatus 10 arranged consistent with the present disclosure, using a mechanical PTO module arrangement. Extending from the topside structure 32 (of the inner member 16) are a plurality (only one shown) of pistons 29-P which move up and down inside a cavity 24A formed in the outer member 14. At the end of the (or each) piston 29-P is a rotatably connected rotor module 410 which has teeth spaced about its circumference. The teeth of the rotor module 410 engage with opposing complimentary toothed racks TR-1, TR-2 which line the interior of the cavity 24A, as shown in Figure 22. Toothed engagement of the rotor module 410 with the racks TR-1 and TR-2 during up / down movement of the piston 29-P (due to movement of the inner member 16 in response to the incident regime) enables rotation of the rotor module. Energy from the rotating rotor module is harnessed by the PTO system 30 (atop the topside structure 32) enabling power generation. The skilled reader would appreciate that multiple rotor modules 410 could be employed.

[0320] Figure 22 shows a schematic diagram of an embodiment of a single WEC apparatus 10 arranged consistent with the present disclosure, using a double acting pneumatic PTO module arrangement. Extending from the topside structure 32 (of the inner member 16) are a plurality (only one shown) of pistons 29-P which move up and down inside the cavity 24A formed in the outer member 14. Extending from the topside structure 32 (of the inner member 16) are a plurality (only 1 shown) of pistons 29-P which move within a pneumatic fluid PF (eg. air) contained within the cavity 24A (formed within the outer member 14) which serves as a pneumatic cylinder. Each piston 29-P terminates with a piston head 29-H. The movement of the piston 29-P is by way of the inner member 16 moving in response to the incident wave regime. The pneumatic PTO module is operable with a PTO system 30 located on the exterior side of the outer member 14. The PTO system 30 comprises a compressor 500 (which is in fluid communication with the pneumatic fluid HF on both sides of the piston head 29-H) and receives incoming pneumatic fluid depending on which side of the piston head 29-H is under a compressive cycle; a first one-way valve 502 for enabling entry of air into the cavity 24A (by suction) above the piston head 29-H when the piston 29-P is moving downwards (eg. recharging that portion of the cavity for the next upward compression cycle); a second one-way valve 504 for enabling entry of air into the cavity 24A (by suction) below the piston head 29-H when the piston 29-P is moving upwards (eg. recharging that portion of the cavity for the next downward compression cycle); a turbine 506 which is driven by incoming pneumatic fluid received from the compressor 500; and a generator module 508 which is in operable communication with the turbine 506. Upward and downward movement of the piston 29-P generates power.

[0321] Materials or the inner and outer members can be any appropriate material suited for the intended environment of operation. Various grades of steel (stainless, galvanized) find ready application. Furthermore, any parts / portions of any of the structures described herein can be fabricated from stiffened plate. The skilled person would be aware of the types of materials and construction techniques applicable to the present disclosure.

[0322] It will be understood that the above examples of PTO module / systems are not limiting and could be implemented in a manner different ways. The examples are designed to be simplified for conciseness of explanation.

[0323] The words used in the specification are words of description rather than limitation, and it is to be understood that the principles of the present disclosure are susceptible to various changes may be made without departing from the spirit and scope of any aspect of the principles described herein. Those skilled in the art will readily appreciate that a wide variety of modifications, variations, alterations, and combinations can be made with respect to the above-described embodiments without departing from the spirit and scope of any aspect of the principles described, and that such modifications, alterations, and combinations are to be viewed as falling within the ambit of the inventive concept. The principles of the present disclosure includes all such modifications, variations, alterations, and combinations.

[0324] The principles of the present disclosure also includes all of the steps and features referred to or indicated in this specification and accompanying drawings, individually or collectively and any and all combinations or any two or more of the steps or features.

Claims

Claims1 . A floating wave energy conversion (WEC) apparatus comprising: an outer member and an inner member arranged in nested or sleeved relation, wherein at least one of the outer member or the inner member is configured to move in response to an incident wave regime, a power take-off (PTO) module operably coupling the inner member and the outer member, at least a portion of the PTO module being accommodated, hosted or housed substantially in one of the outer or the inner members, wherein, in use, relative motion between the outer and the inner members is converted into electrical power.

2. A floating wave energy conversion (WEC) apparatus comprising: an outer member and an inner member arranged in nested or sleeved relation, wherein at least one of the outer member or inner member is configured to move in response to an incident wave regime, a power take-off (PTO) module operably coupling the inner member and the outer member, the PTO module comprising at least a first portion and at least a second portion that are accommodated, hosted or housed substantially in one of the outer or inner members, with one of the at least one first or second portions being coupled or anchored to or with the other of the outer or inner members, wherein, in use, relative motion between the at least one first portion and the at least one second portion is used to generate electrical power.

3. The apparatus of claim 2, wherein the outer and inner members are configurable to be operably coupled by one of a variety of PTO modules for use in converting the relative motion between the outer member and the inner member into electrical power.

4. The apparatus of any one of the preceding claims, wherein the outer member is a vertically extending member having an opening extending vertically therethrough, and the inner member is a vertically extending member provided in the vertical opening of the outer member.

5. The apparatus of any one of the preceding claims, wherein the outer member is operably connected or slidably retained to or with the inner member by a guide means, the guide means being configured to (i) enable vertical movement of the inner member and outer member with respect to each other, and (ii) to limit yaw, twisting or rotational movement of the inner member and outer member with respect to each other.

6. The apparatus of claim 5, wherein the guide means is further configured to limit the axial movement of the inner member and outer member with respect to each other.

7. The apparatus of any claim 5 or claim 6, wherein the guide means is any of a track system, static guide, prismatic coupling, or roller system.

8. The apparatus of any one of the preceding claims, wherein a smallest diameter of an inner surface of the outer member is greater than a largest diameter of an outer surface of the inner member.

9. The apparatus of any one of the preceding claims, wherein at least one of or each of the outer member and the inner member comprise a fixed ballast means provided towards the bottom or base / foot region of the relevant of the outer or the inner member.

10. The apparatus of claim 9, wherein a weight of the fixed ballast means is predetermined to ensure or provide for a stability of the WEC apparatus when in use at a given geographical location in a given sea environment.11 . The apparatus of any one of the preceding claims, wherein at least one of or each of the outer member and the inner member comprise a variable ballast means for adjusting a depth or draft of the respective member in the body of water, wherein the depth or draft of the respective member is calculated such that, in use, the respective member has a predetermined resonance and / or a predetermined phase relationship in an incident wave regime.

12. The apparatus of claim 11 , wherein the variable ballast means comprises at least one vertically extending cavity, provided in a wall of one of or each of the outer member or the inner member, and at least one pumping means for pumping water into and / or out of either or both of the cavities.

13. The apparatus of any one of the preceding claims, wherein the PTO module is selected from the group consisting of linear generators, mechanicalgenerators, hydraulic generators and pneumatic generators, permanent magnet generators, switched reluctance linear generators, multi translator switched reluctance linear generators.

14. The apparatus of any one of the preceding claims, wherein at least one of the outer member and / or inner member comprises at least one vertically extending cavity, configured to house the at least a portion of the PTO module or the at least one first portion or the at least one second portion of the PTO module.

15. The apparatus of claim 14, wherein the PTO module is accommodated, hosted, housed in either the inner member or the outer member and anchored to or with the opposing or alternate member.

16. The apparatus of claim 15, wherein the PTO module is a magnetic linear generator or permanent magnetic linear generator.

17. The apparatus of claim 16, wherein the magnetic linear generator comprises at least one moveable member which is the at least one first portion and at least one stationary member which is the at least one second portion, and wherein the at least one moveable member is configured so as to, in use, move vertically relative to the at least one stationary member.

18. The apparatus of claim 17, wherein the at least one moveable member is arranged so as to slide or translate internal of or within a respective stationary member in a substantially concentric or coaxial manner.

19. The apparatus of claim 17 or claim 18, wherein the at least one moveable member and the at least one stationary member are both accommodated, hosted, or housed and operable in either the inner member or the outer member.

20. The apparatus of claim 19, wherein the at least one moveable member of the PTO module is operably coupled or anchored to or with the other of the inner member or the outer member so as to be moveable in response to movement of said other member when subject to the incident wave regime.21 . The apparatus of any one of claims 17 to 20, wherein the at least one moveable member is a permanent magnet and the at least one stationary member is a coil.

22. The apparatus of any one of claims 17 to 21 , wherein the at least one moveable member is a coil and the at least one stationary member is a permanent magnet.

23. The apparatus of any one of claims 17 to 22, wherein more than one PTO module is used, and spaced relative one another about either the outer or inner member, whichever accommodates, hosts or houses the PTO module(s), in a substantially uniform, even, or equispaced manner about a respective axis of the relevant member.

24. The apparatus of any one of the preceding claims, wherein the PTO module is connected to a PTO system.

25. The apparatus of claim 24, wherein the PTO system is provided on a portion of the WEC apparatus or the inner or the outer members.

26. The apparatus of claim 25, wherein the PTO system is provided on a platform portion of the inner or the outer member.

27. The apparatus of any one of claims 17 to 26 when dependent on claim 17, wherein the at least one stationary member and the at least one movable member is accommodated, hosted, or housed in the outer member, and the at least one moveable member is configured so as to follow movement of the inner member when moving in response to the incident wave regime.

28. The apparatus of claim 27, wherein the at least one stationary member is accommodated, hosted, or housed in a generally vertically extending cavity formed in the outer member.

29. The apparatus of claim 27 or claim 28, wherein the at least one moveable member is anchored with the inner member and extends or is supported from a portion of the inner member.

30. The apparatus of any one of claims 27 to 29, wherein the at least one stationary member is one or more coil(s), and the at least one movable member one or more permanent magnet(s), the or each coil and the or each permanent magnet being accommodated, hosted or housed within the outer member.31 . The apparatus of any one of claims 24 to claim 30, wherein the PTO system is configured so as to, in use, transform the electrical power produced by thePTO module into a first energy product.

32. The apparatus of claim 31 , wherein the PTO system is connected to a subsea power cable configured to provide the energy product to an energy or electricity distribution means.

33. The apparatus of any one of claims 24 to claim 32, wherein the PTO system comprises a control system, the control system configured so as to, in use, (i) measure and monitor WEC performance and input variables, and (ii) adjust variable parameters of the WEC to optimize power production output.

34. The apparatus of any one of claims 24 to claim 33, wherein the PTO system further comprises at least one module selected from the group consisting of a power conditioning module, a monitoring module, and a measuring module.

35. The apparatus of any one of claims 24 to claim 34, wherein the PTO system comprises a measuring module, and the measuring module measures at least one variable selected from the group consisting of displacement, velocity, acceleration, pressure, wave height, power production, power output and geographical positioning.

36. The apparatus of any one of the preceding claims, wherein the WEC apparatus is configured so as to be operably connected to a mooring system, the mooring system comprising an upper portion in fixed communication with the WEC apparatus, and a lower portion in fixed communication with an ocean floor.

37. The apparatus of claim 36, wherein the mooring system is configured so as to substantially limit horizontal movement of the WEC apparatus while allowing relative vertical movement of the outer member and the inner member.

38. The apparatus of claim 36 or claim 37, wherein the mooring system is selected from the group consisting of three (3) point spread mooring system, four (4) point spread mooring system, five (5) point spread mooring system, and six (6) point spread mooring system.

39. The apparatus of any one of the preceding claims, further comprising a releasable locking means, wherein, in use, the locking means is configured so as to, in use, lock the outer member and the inner member together to minimize relative movement therebetween.

40. The apparatus of any one of the preceding claims, wherein a Response Amplitude Operator of the WEC apparatus, when in use, is at least about 0.5 m / m.41 . The apparatus of any one of the preceding claims, wherein a metacentric height of the WEC apparatus, when in use, is at least about 1 m.

42. The apparatus of any one of the preceding claims, wherein a cross-sectional shape of the outer member or the inner member is generally symmetrical about a respective axis of the relevant member.

43. The apparatus of any one of the preceding claims, wherein the or each PTO module is positioned so as to be readily accessible by an operator for operations and servicing / maintenance activities.

44. The apparatus of any one of the preceding claims, wherein a ratio between a draft of the outer member to a dimension defining its outer diameter is about 3:1.

45. The apparatus of any one of the preceding claims, wherein a ratio between a cross-sectional area of the outer and inner members is about 0.5:0.5, where 1.0 represents 100 percent of the cross-sectional area enclosed by an outer diameter of the outer member.

46. The apparatus of any one of the preceding claims, wherein a ratio between a cross-sectional area of the outer and inner members is from about 0.5:0.5 to about 0.7:0.3 or to about 0.3:0.7, or from about 0.7:0.3 to about 0.3:0.7, where 1.0 represents 100 percent of the cross-sectional area enclosed by an outer diameter of the outer member.

47. The apparatus of any one of the preceding claims, further comprising a sponson provided with the outer member, and positioned so as to be semisubmerged or submerged at or near the surface of the body of water in which the apparatus is deployed.

48. The apparatus of any one of the preceding claims, further comprising a heave plate provided with the outer member, and positioned so as to be at or near a distal submerged end of the outer member.

49. The apparatus of any one of the preceding claims, further comprising a heave plate provided with the inner member, and positioned so as to be at or near adistal submerged end of the inner member.

50. The apparatus of claim 48 or claim 49, wherein the or each heave plate is / are configured so as to add additional mass to reduce or minimise motion of the relevant of the inner or outer member hosting the relevant heave plate(s).51 . The apparatus according to any one of claims 1 to 50, further comprising a solar harvesting means, module, or system configured for use in harvesting solar energy for use in generating electrical energy for producing a second energy product.

52. The apparatus according to any one of claims 1 to 51 , wherein the solar harvesting means, module, or system comprises one or more solar panel(s) or solar panel array(s).

53. The apparatus of claim 52, wherein the or each solar panel or solar panel array are in communication with a or the subsea power cable configured to provide the first and / or second energy product(s) to an or the energy distribution means.

54. The apparatus according to claim 51 or claim 52, further comprising an electrical storage means or module for storing the first energy product harvested via the PTO module / system and or the second energy product harvested from the or each solar panel(s) or solar panel array(s).

55. The apparatus according to claim 54, wherein the electrical storage means or module is in communication with a or the subsea power cable configured to provide the first and / or second energy product to an or the energy distribution means.

56. The apparatus of any one of claims 51 to 55, wherein the apparatus is provided in the form of a hybrid energy conversion apparatus or a floating hybrid energy conversion apparatus.

57. A floating support structure comprising a plurality of apparatuses of any one of claims 1 to 56, wherein said apparatuses are interconnected such that each apparatus defines a corner of the floating support structure.

58. The floating support structure of claim 57, wherein the plurality of apparatuses are interconnected by one or more rigid connector(s).

59. The floating support structure of claim 57 or claim 58, wherein the floatingsupport is semi-submerged insofar as, in use, it defines a submerged portion, and a portion that, in use, is located above the surface of the body of water in which it is deployed.

60. The floating support structure of claim 58 or claim 59, wherein the one or more rigid connectors interconnecting at least two apparatuses together are submerged, and comprise one or more tanks or chambers that are operable for use in providing ballast or buoyancy to the floating support structure for ballasting the floating support structure to different drafts or depths.61 . The floating support structure of claim 60, wherein the one or more tanks or chambers of the or each rigid connectors are arranged in fluid communication with a ballasting means of one or more of the apparatuses.

62. The floating support structure of any one of claims 57 to 61 , wherein the portion of the floating support structure or one or more of the rigid connectors that are above or below the surface of the body of water in which the floating support structure is deployed are configured so as to support any of the following: a deck or platform structure, maintenance equipment, monitoring equipment, control equipment, ballasting pumping modules, accommodation / office utilities, maintenance repair stores, solar panel arrays, electrical storage equipment, auxiliary / emergency power equipment, communications equipment, one or more access walkways, a helicopter take- off / landing / recharging infrastructure, a wind turbine, water desalination equipment, hydrogen generating equipment or associated product export equipment, tidal or current driven generator, chemical storage, unmanned aerial vehicle take-off / landing infrastructure, autonomous underwater vehicle docking / recharging infrastructure.

63. The floating support structure of any one of claims 57 to 62, wherein the floating support structure is tethered or moored to the seabed.

64. The floating support structure of any one of claims 57 to 63, wherein the floating support is adapted or configured to support a further apparatus or equipment such as a platform, a wind turbine, tidal or current driven generator, hydrogen generating equipment, or ammonia generating equipment.

65. The floating support structure of any one of claims 57 to 64, further comprising a solar harvesting means, module or system.

66. The floating support structure of any one of claims 57 to 65, further comprising a structure configured to cover across a portion of the floating support structure, the structure configured so as to support a solar harvesting means, module or system thereon for use in harvesting solar energy.

67. The floating support structure of claim 66, wherein the structure is configured for providing a roof or canopy structure atop which one or more solar panel(s) or solar panel array(s) of the solar harvesting means, module or system are positioned.

68. The floating support structure of claim 66 or claim 67, wherein the floating support structure comprises an electrical storage means or module for storing the first energy product harvested via the PTO module / system and or the second energy product harvested from the or each solar panel(s) or solar panel array(s).

69. The floating support structure of claim 68, wherein the electrical storage means or module is in communication with a or the subsea power cable configured to provide the first and / or second energy product(s) to an or the energy distribution means.

70. An energy conversion apparatus or system comprising: a plurality of wave energy conversion (WEC) apparatus arranged according to any one of claims 1 to 56 for use in generating a first energy product and arranged in spaced relation by connecting structure, a solar harvesting means, module, or system for use in generating a second energy product, wherein, in use, the first and / or second energy products are distributable to an energy distribution means.71 . The energy conversion apparatus according of claim 70, wherein the connecting structure interconnects said WEC such that each apparatus defines a corner of the energy conversion apparatus.

72. The energy conversion apparatus of claim 71 , wherein the apparatuses are interconnected by one or more rigid connector(s).

73. The energy conversion apparatus of claim 71 or claim 72, wherein the apparatus is semi-submerged insofar as, in use, it defines a submergedportion, and a portion that, in use, is located above the surface of the body of water in which it is deployed.

74. The energy conversion apparatus of claim 72 or claim 73 when dependent on claim 72, wherein one or more rigid connectors interconnecting at least two apparatuses together are submerged, and comprise one or more tanks or chambers that are operable for use in providing ballast or buoyancy to the for ballasting the energy conversion apparatus to different drafts or depths.

75. The energy conversion apparatus of claim 74, wherein one or more tanks or chambers of the or each rigid connectors are arranged in fluid communication with a ballasting means of one or more of the apparatuses.

76. The energy conversion apparatus of any one of claims 70 to 75, wherein the portion of the energy conversion apparatus or one or more of the rigid connectors that are above or below the surface of the body of water in which the energy conversion apparatus is deployed are configured so as to support any of the following: a deck or platform structure, maintenance equipment, monitoring equipment, control equipment, ballasting pumping modules, accommodation / office utilities, maintenance repair stores, solar panel arrays, electrical storage equipment, auxiliary / emergency power equipment, communications equipment, one or more access walkways, a helicopter take- off / landing / recharging infrastructure, a wind turbine, water desalination equipment, hydrogen generating equipment or associated product export equipment, tidal or current driven generator, chemical storage, unmanned aerial vehicle take-off / landing / recharging infrastructure, autonomous underwater vehicle docking / recharging infrastructure.

77. The energy conversion apparatus of any one of claims 70 to 76, wherein the energy conversion apparatus is tethered or moored to the seabed.

78. The energy conversion apparatus of any one of claims 70 to 77, wherein the energy conversion apparatus is adapted or configured to support a second apparatus or member such as a platform, a wind turbine, tidal or current driven generator, or hydrogen generating equipment.

79. The energy conversion apparatus of any one of claims 70 to 78, further comprising a structure configured to cover across a portion of the energy conversion apparatus, the structure configured so as to support the solar harvesting means, module or system.

80. The energy conversion apparatus of claim 79, wherein the structure is configured for providing a roof or canopy structure atop which the solar harvesting means, module or system is positioned.81 . The energy conversion apparatus of claim 78 or claim 79, wherein the energy conversion apparatus comprises an electrical energy storage means or module for storing the first energy product harvested via the PTO module / system and or the second energy product harvested from the or each solar panel(s) or solar panel array(s).

82. The energy conversion apparatus of claim 81 , wherein the electrical energy storage means or module is in communication with a or the subsea power cable configured to provide the first and / or second energy product to an or the energy distribution means.

83. The energy conversion apparatus of any one of claims 70 to 82, wherein the apparatus is a hybrid energy conversion apparatus or a floating hybrid energy conversion apparatus.

84. A method for generating energy, the method comprising the steps of: a. providing a first vertically extending outer member and a second vertically extending inner member; and b. adjusting a ballast of at least one of the first and second members to a to a predetermined depth, wherein, in use, the depth or draft of the first and second members is determined to ensure at least one of the first and second members is moving or resonating in response to in an incident wave regime.

85. The method of claim 84, wherein the step of adjusting a ballast of at least one of the first and second members to a predetermined depth or draft, comprises adjusting a variable ballast means of at least one of the first and second members to a predetermined amount or weight.

86. The method of claim 84 or claim 85, wherein the first and second members are ballasted to different depths or drafts relative to one another.

87. The method of any one of claims 84 to 86, wherein the first and second members resonate at different wave frequencies.

88. The method of any one of claims 84 to 87, wherein the first and second members resonate out of phase with each other.

89. The method of any one of claims 84 to 88, wherein the method further comprises providing a power take off device or module (PTO) operably connected between the first and second members, wherein the relative motion of the first and second members drives the PTO module and produces an electrical product.

90. The method of claim 89, wherein the method further comprises adjusting the operational characteristics of the PTO modules to suit for increasing or maximising power absorption, conversion and / or electricity production of the WEC apparatus.91 . The method of any one of claims 89 or 90, wherein the PTO is a magnetic linear generator having at least one moveable member and at least one stationary member provided on the first outer member, wherein the at least one moveable member is anchored to or with the second inner member, and wherein the relative motion of the first and second members drives the moveable member past the stationary member.

92. The method of any one of claims 89 to 91 , wherein the PTO is a magnetic linear generator having least one moveable member and at least one stationary member provided on the second inner member, wherein the at least one moveable member is anchored to or with the first outer member, and wherein the relative motion of the first and second members drives the moveable member past the stationary member.

93. The method of any one of claims 92, wherein the moveable member is a permanent magnet, and the stationary member is a coil.

94. The method of claim 92, wherein the moveable member is a coil and the stationary member is a permanent magnet.

95. The method of any one of claims 89 to 94, wherein the step of adjusting a ballast of at least one of the first and second members, is performed by a control system.

96. The method of any one of claims 89 to 95, wherein the electrical product is a first energy product, and the method further comprises providing for operation one or more solar panel(s) or array(s) of solar panels for use in generating a second electrical product.

97. The method of any one of claims 89 to 96, further comprising storing the firstand / or second electrical product in a storage means or module.

98. The method of any one of claims 89 to 97, further comprising distributing the first and / or second electrical product to a distribution means.

99. The method of any one of claims 89 to 98, further comprising distributing the first and / or second electrical products to an electrical grid.

100. The method of any one of claims 89 to 99, wherein the PTO is any one of the following: linear generator(s), mechanical generator(s), hydraulic generator(s) and pneumatic generator(s), permanent magnet generator(s), switched reluctance linear generator(s), multi translator switched reluctance linear generator(s).

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