WO2022123273A2

WO2022123273A2 - Waterborne vessel

Info

Publication number: WO2022123273A2
Application number: PCT/GB2021/053253
Authority: WO
Inventors: Simon ROGERS
Original assignee: Windship Technology Limited
Priority date: 2020-12-11
Filing date: 2021-12-10
Publication date: 2022-06-16
Also published as: GB202019582D0; WO2022123273A3

Abstract

A waterborne vessel comprising an engine room arranged to accommodate one or more power modules to provide power for use by the vessel, and the engine room arranged to accommodate the one or more power modules in an interchangeable manner, and the waterborne vessel provided with access arranged to allow at least one of the power modules to be conveyed from inside the engine room to externally of the vessel, through the access, and vice versa, and wherein the engine room is provided in or as part of a superstructure of the vessel.

Description

WATERBORNE VESSEL

Technical Field

The present invention relates generally to improvements in relation to waterborne vessels.

Background

Vessels such as cargo vessels, are very often designed on the basis of building the structure around the engine room, in essence that the engine room is the de facto starting point. This results in vessels in which the engine room is located in a lower part of the vessel. This means that when the vessel reaches the end of its operational/serviceable life, there is minimal possibility for the vessel to be retained because the engine cannot be removed and replaced (due to the location of the engine room). Rather, the vessel will very often need to be decommissioned and scrapped. This is a process which is costly and which releases a significant amount of CO2 into the atmosphere.

It has been proposed to provide cargo vessels with aerofoil sails to provide an alternative/supplementary form of propulsion to the use of diesel engines. Whilst it is envisaged that vessels equipped with such sails would nevertheless be provided with engines, the use of the sails would allow a significantly reduced amount of fuel to be used, thus reducing carbon emitted into the atmosphere. However, we have realised that when it is required to use both wind power and engine power, that it may be very inefficient to achieve the optimum power output derived from the engine(s).

We have devised an improved waterborne vessel. We have also devised an improved powertrain for waterborne vessels.

Summary

According to a first aspect of the invention there is provided a waterborne vessel comprising: a power compartment arranged to accommodate one or more power modules to provide power for use by the vessel, and the waterborne vessel provided with access arranged to allow at least one of the power modules to be conveyed from inside the power compartment to externally of the vessel, and vice versa. The access may be arranged to allow for a power module to be conveyed from externally of the vessel to within the engine room, for example in the case of installing a power module at the time of ship build and/or swapping a existing power module for a replacement module (such as for the purpose of an upgrade or refit of the vessel).

The access may comprise an opening or more generally a space which is shaped and/or dimensioned to allow a power module to pass therethrough.

The access may provide direct access to the engine room.

The access may be provided in an externally facing (side) structure of the vessel.

The access may be a fixed or permanent feature of the vessel.

The vessel may be a cargo vessel or ‘bulker’. The vessel may be a passenger liner.

The engine room may be located on an upper deck of the vessel. By upper deck we include a deck other than the lowermost deck, or other than the lowermost space of the vessel, or one of the lower decks. The upper deck may be a weather deck. The upper deck may be the coach roof or deck. The upper deck may be any of up to three decks below the weather deck. The power compartment may be viewed as being at an upper region of the vessel. The upper deck need not necessarily be the uppermost deck.

The invention may be viewed as providing an engine room on a deck other than on a lowermost, or a lower, deck of the vessel. The engine room may be termed a compartment of the vessel.

The access may be provided in a side region of the vessel. The access may be provided in a superstructure of the vessel or in the hull of the vessel. By superstructure we include a structure which extends above the working deck or weather deck of the vessel.

The access may allow access to the (upper) deck on which the power modules are situated, or arranged to be situated. The access may comprise a door or hatch, or more generally a closure, which can adopt an open condition and a closed condition, which may comprise a slidable door.

More than one access may be provided, with each access opening provided at a respective location. There may be provided (at least) two accesses each which is provided on a opposite side region of the vessel, such as providing an access on port side and a second access on starboard side. An access may be termed an access point or access region.

A deck or level of the vessel on which the power modules are located may be provided with a guide structure (such as rails or tracks , for example) which are arranged to enable or facilitate a power module to be moved from one location to a different location on the deck and/or within the engine room. The guide structure may be arranged to allow a power module to be moved from a location adjacent or proximal to the access, to a different location which is its operational location. The guide structure may extend from the access opening to the operational location. The guide structure may be arranged to provide for translational movement of a power module.

The guide structure may extend externally of the engine room as well as internally of said engine room.

The operational location (of the power module) may be provided with a locking or fixing assembly which serves to (detachably) secure a power module at the operational location. The power module may be provided with a locking or fixing assembly in addition or alternatively to any such feature provided at the operational location.

The operational location may comprise a number of stations, each station arranged to receive and locate a respective power module.

It will be appreciated that the power modules (where multiple power modules are provided) need not necessarily be provided on same deck or level, and may be provided on multiple decks/levels. Said multiple decks may be two or more upper decks. In this case there may be provided more than one engine room, each of which may be provided with its respective access/es. The engine room may be provided in or be part of the superstructure of the vessel, and this may be the main, principal or largest superstructure of the vessel. The superstructure may comprise at least one of the bridge of the vessel and crew accommodation. The superstructure may be located towards , at or adjacent to a distal end, fore or aft, of the vessel.

A power module may be provided with one or more of a generator, power generation and a battery.

According to a second aspect of the invention there is provided a powertrain for a waterborne vessel, comprising: a power module arranged to provide a power output for use by the vessel, the power module supported on a transportation structure and arranged for power generating operation whilst on the transportation structure, and said power module arranged to be capable of being conveyed from the vessel for removal or interchange.

There may be provided multiple power modules. At least one or some, or all, may be arranged to be capable of being conveyed from the vessel for the purpose of being interchangeable.

The power modules may be arranged to be selectively configurable in at least two permutations to operatively deliver power, wherein for each permutation one or more of the power modules delivers power to the propulsion assembly, or for use otherwise by the vessel.

An aspect of the invention may be viewed as providing a modularised powertrain which enables a particular combination of selected power modules to be made so as to provide a desired (cumulative) power output.

Possible permutations of the power modules may include that one, some or all of the power modules can be selected to provide operative power output at a particular instant. By ‘power output’ we may include that each of the modules provides a respective power output value in which a power module is capable of delivering, or a range of power output values. This or each of these may be termed a power rating of the power module. This may include a power output which a power module is designed to operationally deliver.

The power modules may comprise at least two power modules having substantially the same power output.

The power modules may comprise at least two power modules having different power outputs. At least three power modules may be provided which each have a different respective power output.

The power modules may comprise at least two power modules each having a first power output and at least two power modules each having a second power output, wherein the first power output is greater than the second power output.

The power modules may comprise at least three power modules which have different respective power outputs.

The power output of a power module may be, or substantially correspond to, a power rating of a respective power module. The, each or at least some of the power modules, may be arranged to operate at less than the power rating (s), which may be in the range of 50% to 100% of the power rating(s).

The power modules may be arranged to provide power for use by an electric motor, which motor drives a propeller shaft.

At least one of the power modules may comprise a diesel engine. At least one of the power modules may comprise a combustion engine. At least one of the power modules may comprise a liquefied natural gas (LNG) engine, an ammonia engine and/or a hydrogen engine. More generally, at least one of the power modules may comprise a power source, which can be of any currently known type or any future type. At least one of the power modules may comprise a battery. At least one of the power modules may comprise a generator, which is arranged to cause an electrical power output to be generated. The generator may be arranged to receive a rotational input from a combustion engine.

There may be provided a controller which enables a selected one of the permutations to provide power to the propulsion assembly. The controller may comprise a switch.

Control of which permutation delivers power to the propulsion assembly (at a particular instance) may be effected manually, semi-automatically or be (substantially) fully automated. At least two of those may be selectable as modes of operation.

Where a plurality of power modules are provided, these may be considered as a bank of power modules.

At least one of the power modules may be provided on a transportation structure. The transportation structure may at least in part facilitate movement of the power module from a first location to a different location onboard the vessel. The transportation structure may be provided with wheels or slides.

Where a plurality of power modules is provided the power modules may be controllable so as to determine a (collective) power output, which is controllable to be tailored to an (instantaneous) load cases. The plurality of the power modules can be seen as having a granularity, so that a power output can be achieved based on using one or more of the modules. Since multiple modules may be used to provide a required power output, a number of smaller (in relation to their individual power ratings) power modules can be used, in place of one or more power modules with a higher power rating. This allows multiple lower rated modules to be used at below their power rating(s), and thereby prolonged the operational life of the modules. This aspect may be viewed as a bank of low(er) rated power modules which collectively provide (high) granularity, and thereby providing agility to be responsive to different load cases, or load demands, as these may vary over time. The extent of control provided may include operating one, some or all of the power modules, at respective outputs (which may be substantially the same, or may be different for one, some or all of the power modules selected to deliver power).

Each power module may be referred to as a power pack. The transportation structure may have (standardised) principal dimensions which conform (substantially at least) to that a used for transportation/shipping of goods. The transportation structure may be termed a flatrack.

The transportation structure may have a principal length dimension of substantially 6.1m (20 feet) or substantially 12.2m (40 feet), for example, or may be of other principal standard dimensions. The principal dimensions of the transportation structure may correspond to at least some of those of a standardised shipping container, such as an ISO shipping container. The transportation structure may comprise a width which substantially corresponds to a standardised width of a transportation structure, such as 2.438m (8 feet).

The transportation structure may comprise one or more features or formations which are intended to allow the structure to be lifted, and/or to be nested (on or more other transportation structures in stacked formation).

The transportation structure may comprise a base or platform, on which a power module is situated. The base or platform may be of substantially oblong -rectangular shape (when viewed in plan).

The transportation structure may comprise end walls, an end wall provided at each longitudinal end thereof. The transportation structure may be devoid of side walls (and so may be termed an open or partially open, structure).

The transportation structure may be termed an open sided shipping container/structure.

The transportation structure is preferably configured to not only enable a power module to be moved to and from a required position on a deck, but also to support the power module during operation (once installed and commissioned on a vessel). The transportation structure may be or serve as in use a mount for the power module, during its operational use when installed on a vessel.

In the context of the present invention the transportation structure may be termed a carriage. Each such power module may be provided on a transportation structure, which is supported on the guide structure. The transportation structure may comprise one or more wheels and/or one or more slides.

One or more of the power modules may be detachably connectable to / mounted on the respective transportation structure.

One power module may be provided on a respective transportation assembly. Multiple power modules may be provided on (single) transportation structure. In an implementation there may be one or more single power modules provided a respective transportation assembly and one or more multiple power modules provided on a respective transportation assembly. In another implementation all of the power modules may be single power modules which are provided on respective transportation assemblies. In yet another implementation all of power modules may be multiple power modules provided on a respective transportation assembly.

A power module may be detachably connected to or detachably located on the transportation structure. Alternatively, a power module may be permanently or semi permanently fixed to or be integral with a transportation structure.

The propulsion assembly may comprise an electric motor assembly. The electric motor assembly may comprise an electric motor module.

The electric motor assembly may be arranged to driveably connect/couple to the propeller shaft, either directly or indirectly.

The electric motor assembly may be arranged to selectably driveably engage with the propeller shaft.

The power modules may be controllable so as to determine a power input supplied to the electric motor assembly, which power input at least in part determines a rotational speed of the propeller.

The propulsion assembly may comprise a (single) electric motor, wherein the power supplied to drive the motor is determined by which of the power modules is selected (at a particular moment). The vessel may comprise rigid aerofoil sails to provide a propulsion which is additional to and/or as an alternative to the propulsion provided by the propeller. The rigid aerofoil sails may comprise a leading aerofoil portion and a trailing aerofoil portion, wherein the leading aerofoil portion is longer than the trailing aerofoil portion. There may be provided multiple aerofoil sails provided as an aerofoil sail assembly, which are supported on a common mount or spar. The vessel may comprise multiple aerofoil sail assemblies. The assemblies may be spaced along a length of the vessel. The rigid aerofoil sails may be those as disclosed in W02014001824, the contents of which are incorporated by reference. The vessel may include alternative arrangements for providing at least some vessel’s propulsion from wind, and need not necessarily be those as disclosed in W02014001824.

There may be provided a heat recovery assembly, which is arranged to receive heat exhausted from the power modules, and to convert said heat into an electrical output. The electrical output may be available for use in providing power to the propulsion assembly.

The invention may include an assembly for converting incident solar energy into electrical energy.

There may be provided an electrical bus which receives the electrical output derived from one, some or all of the power modules. The bus may also be arranged to receive as an input the electrical output from the solar assembly and/or the heat recovery assembly. An output line of the bus may be connected to an inverter. An outlet line of the inverter may be connected to the electric motor assembly.

According to a further aspect of the invention there is provided a waterborne vessel of the first aspect of the invention which comprises the powertrain of the second aspect of the invention.

According to a further aspect of the invention there is provided a power module for installation on a waterborne vessel, the power module arranged to provide power for use by the vessel, and the power module provided on a transportation structure, and the transportation structure arranged to facilitate transportation of the power module to and/or from the vessel, and the transportation structure arranged to serve as a mount for the power module during operation when installed on the vessel. The power module may be arranged to be an interchangeable power module.

According to another aspect of the invention there is provided a method of providing power to a drive load of a vessel, the method comprising the use of multiple power modules, which are selectively controllable, including to provide a power output as a single selected power module and including to provide a power output as a selected subset of the power modules.

Any of the of above aspects may additionally or alternatively include one or more features as described in the description and/or as shown in the drawings, either singularly or in combination.

Brief Description of the Drawings

Various embodiments of the invention will now be described by way of example only in which:

Figure 1 is a schematic representation of a powertrain system,

Figure 2 is a side elevation of a waterbourne vessel which includes the powertrain system of Figure 1 ,

Figure 3 is a plan view of the engine room of the vessel of Figure 2,

Figure 4 is a (schematic) side elevation of an engine and generator of the powertrain system of Figure 1 ,

Figure 5 is a schematic side view of a vessel provided with rigid aerofoil sail assemblies, and

Figure 6 is perspective view of a rigid sail assembly of the vessel of Figure 5.

Detailed Description

There is now described a novel powertrain for a waterborne vessel, and also a novel waterborne vessel which includes the powertrain. The various embodiments of waterborne vessel now described include an engine room which advantageously allows for a bank power generating engine modules situated therein to be changed, removed or upgraded in part or in totality, in a way which is not generally possible for known waterborne vessels. Known vessels, such as cargo ships, have an engine room which is located in a lowermost region of the ship, which largely prevents engines from being straightforward or possible to replace (once installed).

As will be described below, the powertrain provided in the engine room advantageously provides a modularised solution such that a selected number of power modules can b e used at any one time, and the selection made is tailored to the prevailing propulsion power requirements. The powertrain is of particular benefit in the context of the vessel being provided with aerofoil sails which provide propulsion by wind power additionally or alternatively (at any one time) to the propulsion provided by an engine powered propeller of the vessel. However, the powertrain described below may be used on ‘conventional’ vessels, which are not equipped with such aerofoil sails.

Reference is made initially to Figure 1 , which shows a system schematic of a powertrain according to an embodiment of the invention. It should be highlighted that the various power values shown are intended as by way of a non-limiting example. Other power output values and combinations are evidently possible in variant implementations.

The powertrain system shown comprises a number of power modules, with some having larger power output (2MW in the example shown) and others having a smaller power output (0.5MW in the example shown). Each power module comprises a diesel engine which is coupled to an electrical generator.

Each generator comprises an electrical output which is connected to a rectifier. From the rectifier, there is a respective connection to a DC bus, which comprises a copper bar.

Each of the diesel engines produces exhaust gases and a heat recovery assembly is advantageously provided to capture the heat in these gases and make this available for use subsequently. The heat recovery assembly comprises a heat exchanger which transfers at least some of the heat from the exhaust gas to a medium contained in a heat transfer circuit, which medium is heated (such as to a gaseous state), which can then be converted to produce an electrical output.

There is further provided a number of solar panels which are exposed to incident solar radiation. In the system shown, the captured solar energy is converted to the electrical domain, which is connected as a further input to the DC bus.

With further reference to Figure 1 , the vessel comprises a propeller, a propeller shaft and an electric motor assembly. The electric motor assembly is arranged to be capable of driving the propeller at a required speed of rotation. The propeller may be of the controllable pitch type (CPP) or may be of fixed pitch type.

The electric motor assembly comprises an electric motor module. In use, having multiple electric power modules means that the drive power delivered to the propeller shaft can be tailored to prevailing conditions. For example, in the instance that the vessel is provided with rigid aerofoil sails, and the wind strength increases, the number of electric modules which are activated to power the electric motor for the propeller can be modified. Moreover, by virtue of having a bank/suite of multiple power modules with different power outputs, it is possible to precisely tailor the power required for a required propeller speed, since many power output permutations are possible. Using conventional engine solutions, to reduce the engine speed is highly inefficient. However, with the arrangement shown there is no such disadvantage (or any inefficiency is substantially minimised).

A controller is provided to control which of the engines is used to provide power. The controller may output control signals in any one of a manual, semi -automated mode or fully automated mode. The controller is configured to provide a control signal to the engines (directly or indirectly) and/or to a power management module, so as to select which of them is used to generate power. The controller can also be used to determine which of the other power sources (for example, solar or heat recovery) are used at any one point. The controller may also be used to determine which proportion of power available or generated is used for propulsion purposes, and/or for use in providing auxiliary power (further details of which are described below). The control functionality may be implemented at least in part by the power management unit shown in Figure 1. Reference is now made to Figures 2 and 3. These serve to illustrate how the power modules can be loaded and located on a vessel. The vessel is provided with a side opening provided in an externally facing structure of the vessel, which serves in use to provide access to an engine room, in which the multiple power modules are provided. In contrast to known vessels, the engine room is provided on or as an upper deck of the vessel. In the example shown, the engine room is provided within a space provided in a side wall of the sole or main superstructure of the vessel (and directly below the bridge, and/or any crew accommodation may be provided in the superstructure). The access opening to the engine room is provided in a side wall of the superstructure. Figure 3 also shows a second access opening on an opposite side wall of the superstructure, which is also provided with a slidable door.

The floor of the engine room is provided with tracks. The tracks are arranged to support and guide a flatrack transportation container. One or more power modules are provided on a respective flatrack shipping platform. It is to be noted from Figure 1 that each of the larger (rated) power modules has a respective container and the lower (rated) power modules are all provided on a single flat rack container.

With reference to Figure 4, there is shown a diesel engine and generator mounted on a transportation container. The transportation container comprises a base or platform, an upper side of which supports the engine and the generator. An underside of the platform is provided with wheels or slides which are arranged to engage with the tracks. The base of the transportation container is of substantially oblong -rectangular shape, and has a (principal) external length dimension which is substantially that of a standardised shipping container, such as one conforming to ISO standards. The widths of the distal ends of the platform may substantially correspond to a standardised width, such as 2.438m (8 feet). The transportation container shown is a flat rack transportation container, and would not usually include side walls (extending along the long sides of the platform), but may include end walls, which may be arranged to be detachable from the platform. As can be seen in Figure 3, two sets of tracks are provided, orthogonally of each other. These enable each power module to be conveyed from the access opening to a required operational position. One set of tracks allows translation of the power modules laterally of the vessel, and the second set of tracks allows translation of the power modules longitudinally of the vessel. Once the power modules are urged through the access opening along the first set of tracks, one at a time, they are then moved along the second set of tracks to a respective operational position. Other configurations and arrangements of tracks are of course realisable.

Although not shown in Figure 3, there is provided a lock or fastener assembly, by which each power module is held or locked in its operation position. This ensures that each power module is maintained fast with the frame of reference of the vessel in its operational position.

During the build and commissioning of the vessel, the power modules can be lifted (for example by a crane) or otherwise conveyed next to or within an access opening from shore side, onto the first set of tracks. In the example shown, the first set of tracks extends beyond or is proximal to the access opening, to allow the lifting device to place a power module on the tracks, externally of the engine room. That portion of the tracks which extends beyond the access opening and externally of the engine room, is supported on the working or weather deck. Loading (and unloading) of the power modules with respect to the vessel is facilitated thanks to formations provided by the flatrack shipping platform provided for that purpose.

Subsequently, in the event that it is required to subsequently replace, remove one or more installed power modules or include one or more additional power modules , this can be achieved in a straightforward manner. In many conventional vessels the engine room occupies a compartment in a lower region of the ship, and so post -build removal of the engine is not a trivial undertaking, and in many cases may be completely unfeasible to remove an engine in its entirety (at least without significant disassembly). The power module which is to be replaced is first unlocked or detached from its operational position. This (operational position) is the position at which the module is located on the transportation container and connected to the powertrain system. The power module can then be moved along the tracks towards the access opening. Once in a position adjacent to the opening, a crane or the like can be used to attach to and lift the module from the vessel. A replacement power module is then lifted onto the vessel adjacent to the opening, which can then be moved on the tracks into the operational position occupied by removed power module.

By providing an engine room like that in the embodiment shown and described, allows for vessels which would otherwise need to be decommissioned and scrapped to be retained in service. In the event that all of the engine modules reach the end of their operational and serviceable life, they can simply be removed from the vessel and replaced with new ones. For vessels in which the engine room is not like that disclosed here, it is usually largely unfeasible to swap out the primary engine. By having the interchangeability of engine modules, avoids the result of significant quantity of CO2 entering the atmosphere as a result of the scrapping of the vessel.

The interchangeability of engine modules also advantageously allows for swapping to more efficient engines and environmentally friendly engines, as and when these become available. A requirement to use a more efficient power source may come about as a result of a change in legislation, for example. The facility to be able to interchange engine modules therefore future-proofs a vessel so that it is capable of conforming to any future legislative requirements to fuel type or engine type.

It will be appreciated that because the power modules are provided on shipping containers having standardised shipping container dimensions they can more easily be transported to the vessel (for example by road) and can then remain on the container during loading, installation and operation. This further adds to efficiency and ease of installing such modules.

One of the particular advantages of the arrangement described above is that a vessel does not need to be designed around an engine room, as is currently the case, or at least to a much lesser extent.

In the example described above, the power generated by the engine modules is for use providing propulsion to the vessel. However, the power modules can be used for both provision of propulsion power and as a source of providing auxiliary power for the vessel, such as for lighting and powering other electrical equipment aboard the vessel. As a further alternative, the power modules may provide only auxiliary power (i.e. not for propulsion). It may be in a further embodiment that the use of any power generated by the power modules may be controllable to be selected for use for one purpose only or for a combination.

Reference above is made to vessel which is provided with rigid aerofoil sails to provide main, supplementary or additional propulsion. Figure 5 shows such a vessel and Figure 6 shows a rig or assembly 100 of three aerofoil sails. The vessel in Figure 5 is a cargo vessel which is provided with three rigid sail assemblies, spaced along the deck of the vessel. With reference to Figure 6, each assembly 100 comprises three aerofoil sails, each of which comprises a leading aerofoil portion 103 which is longer than a trailing aerofoil portion 105. The sails are mounted on a spar, which is arranged to rotatable to a required angular position. The trailing aerofoil portion or flap, is pivotable relative to the leading portion, and its angular position can be controlled accordingly. These various adjustable characteristics of the sail assembly require a power input (for servo motors, drives etc.). As indicated schematically in Figure 1 , this power can be provided by any of the power sources.

In another embodiment of the invention, access to an engine room may be provided alternatively or additionally to being provided at one or more sides of the vessel, in a weather deck or working deck, otherwise an uppermost externally facing surface of the vessel, with the engine room provided below the deck. Such an implementation may allow the power modules to be loaded or unloaded directly to or from the engine room. In a further embodiment of the invention, there may be provided a carbon capture arrangement and or process, in which calcium oxide (or similar or equivalent) is introduced into the exhaust. This advantageously yet further reduces the carbon emissions of the vessel.

Claims

1. A waterborne vessel comprising: an engine room arranged to accommodate one or more power modules to provide power for use by the vessel, and the engine room arranged to accommodate the one or more power modules in an interchangeable manner, and the waterborne vessel provided with access arranged to allow at least one of the power modules to be conveyed from inside the engine room to externally of the vessel, through the access, and vice versa, and wherein the engine room is provided in or as part of a superstructure of the vessel.

2. A waterborne vessel as claimed in claim 1 in which the engine room is located in an upper region of the vessel.

3. A waterborne vessel as claimed in claim 1 or claim 2 in which the engine room is located other than at or in a lowermost region of the vessel.

4. A waterborne vessel as claimed in any preceding claim in which the engine room is located on a weather deck or a working deck or up to three decks below the weather deck or the working deck.

5. A waterborne vessel as claimed in any preceding claim in which the engine room is located on an upper deck of the vessel.

6. A waterborne vessel as claimed in any preceding claim in which the access comprises an opening or a space which is shaped and/or dimensioned to allow a power module to pass therethrough.

7. A waterborne vessel as claimed in any preceding claim in which the access comprises an opening formed in a side structure of the vessel.

8. A waterborne vessel as claimed in claim 6 in which the access is provided in the superstructure of the vessel.

9. A waterborne vessel as claimed in any preceding claim in which the engine room is provided in or as part of the main superstructure of the vessel.

10. A waterborne vessel as claimed in any preceding claim in which the engine room comprises a floor which is provide with a guide structure, the guide structure arranged to enable a power module to be conveyed in the power compartment.

11. A waterborne vessel as claimed in claim 10 in which the guide structure comprises one or more rails or tracks.

12. A waterborne vessel as claimed in claim 11 in which the guide structure is arranged to convey a power module from a location at or adjacent the access, to or adjacent to an operational location.

13. A waterborne vessel as claimed in any preceding claim which comprises one or more wind propulsion assemblies which are arranged to be capable of providing at least a proportion of the propulsion of the vessel.

14. A waterborne vessel as claimed in claim 13 in which the at least one wind propulsion assembly comprises one or more rigid, aerofoil sails.

15. A waterborne vessel as claimed in claim 14 in which the wind propulsion assembly comprises a leading aerofoil sail and a trailing aerofoil sail.

16. A powertrain for a waterborne vessel, comprising: multiple power modules arranged to provide a power output for use by the vessel, each power module supported on a transportation structure and arranged for power generating operation whilst on the transportation structure, and said power module arranged to be capable of being conveyed from the vessel for removal or interchange. 19

17. A powertrain system comprising the powertrain of claim 16, and the system comprising a controller arranged to effect selective use of the power modules so as to tailor a power output to a load demand.

18. A method of providing power for a load demand of a vessel, the method comprising the use of multiple power modules, each power module supported on a transportation structure, and which power modules are selectively controllable, including to provide a power output as a single selected power module and including to provide a power output as a selected subset of the power modules.