WO2014139532A1

WO2014139532A1 - Method and apparatus for handling a wind turbine tower for quay side assembly and storage, and transport to an off-shore installation site

Info

Publication number: WO2014139532A1
Application number: PCT/DK2014/050046
Authority: WO
Inventors: Adrian Botwright
Original assignee: Mhi Vestas Offshore Wind A/S
Priority date: 2013-03-13
Filing date: 2014-03-05
Publication date: 2014-09-18

Abstract

An apparatus for handling wind turbine towers includes a structure coupled to a quay side in a manner that supports reversible tensile and compressive loading of the structure, and a tower stand configured to be coupled to a wind turbine tower and further configured to be coupled to the structure, wherein when the tower stand, having a tower coupled thereto, is coupled to the structure, the tower is coupled to the quay side in a manner that supports reversible tensile and compressive loading of the tower. A method for handling wind turbine towers is also disclosed and includes coupling a tower to the structure and moving the tower on the quay side, wherein the tower is coupled to the structure in a manner that supports reversible tensile and compressive loading of the tower.

Description

METHOD AND APPARATUS FOR HANDLING A WIND TURBINE TOWER FOR QUAY SIDE ASSEMBLY AND STORAGE, AND TRANSPORT TO AN OFF-SHORE INSTALLATION SITE

Technical Field

[0001] This application relates generally to wind turbines, and more particularly to a method and apparatus for handling wind turbine towers on the quay side and on a seafaring vessel for transport to an off-shore installation site.

Background

[0002] Wind turbines are used to produce electrical energy using a renewable resource and without combusting a fossil fuel. Generally, a wind turbine converts kinetic energy from the wind into mechanical energy and then subsequently converts the mechanical energy into electrical power. A horizontal-axis wind turbine includes a tower, a nacelle located at the apex of the tower, and a rotor that is supported in the nacelle. The rotor is coupled either directly or indirectly with a generator, which is housed inside the nacelle. The rotor includes a central hub and a plurality of blades (e.g., three blades) mounted thereto and extending radially therefrom. [0003] Modern multi-megawatt wind turbines are massive structures and are generally assembled from smaller component parts. In this regard, many off-shore wind turbines have their various components delivered to a quay side for subsequent delivery to the off-shore installation site. Some installation procedures may call for some amount of assembly quay side resulting in a number of main component assemblies. For example, the wind turbine tower, which may be formed by a number of tower sections, may be assembled quay side for delivery to an off-shore installation site. The nacelle may also be delivered quay side in a complete or nearly-complete form.

Lastly, the blades, themselves being quite massive in size, may be delivered quay side for subsequent delivery to the off-shore installation site. These various main component assemblies, e.g., the tower, nacelle, and blades, are then loaded onto a seafaring vessel and transported to the installation site for final assembly.

[0004] For efficient installation of an off-shore wind farm, for example, the vessel will be loaded with as many complete wind turbines as possible. The vessel will carry the main component assemblies for a number of complete wind turbines. The number of complete wind turbines depends upon several factors, including the particular vessel utilized for transport. Each time the vessel docks at the quay side, the vessel will generally receive a full load of wind turbines. For efficient loading of the vessel, all the main component assemblies, for example, all the towers, will be serially arranged along the quay side adjacent the water edge in an upright orientation prior to the docking of the vessel along the quay side. All the main component assemblies, including the towers, must be located close to the water edge so as to be within reach of the vessel's onboard crane or other loading crane. In this way, the crane may load the main component assemblies onto the vessel without having to move the position of the vessel along the quay side.

[0005] In this regard, the upright towers may be on the quay side for several days prior to being loaded on the vessel. During this time, the towers are subject to potentially large wind forces and therefore, must be supported in some manner so as to prevent the towers from falling over. Current systems and techniques for supporting the towers call for fixedly coupling each of the towers to a tower stand having a relatively large square or rectangular base for supporting the tower. The base then rests upon the quay side without further physical coupling of the base to the quay side. The enlarged footprint of the base on the quay side then prevents the tower from falling over when subjected to loads induced by the wind or other forces. The size of the tower base may be selected based on estimated worst-case wind conditions at the quay side. By way of example, for a 60-70 m tower, weighing between about 150-170 tonnes, the tower base may have a dimension of about 9.5 m x 9.5 m to prevent the tower from falling over under estimated worst-case wind conditions. The increased footprint of the tower stand also distributes the load from the tower into the quay side, thereby reducing the required strength of the quay side. If the quay side cannot support the weight of the tower, then some method of ground improvement is necessary, which is costly. However, as a result of the increased footprint, a significant amount of the quay side is taken up by the tower stands. This results in a relatively open spacing of the main component assemblies at the quay side, thereby occupying a significant amount of quay area and making it difficult for the vessel to be able to reach and lift all the main components onboard the vessel for the next installation trip without moving the vessel along the quay side. As the capacity of the vessel increases, the number of main component assemblies increases, and hence the more widespread the components are, the more quay area is required, and the more difficult to reach the components with the vessel's onboard crane.

[0006] The current trend in the wind industry is for wind turbines to increase in size and weight. For example, it is expected that the next generation of wind turbine towers will reach 90-100 m in height and have a weight of about 350-450 tonnes. Wind turbines of this size present some practical challenges in regard to handling of the wind turbine components on the quay side in preparation for being transported to an off-shore installation site. By way of example, using current methodologies, a tower stand configured to support a 90 m tower on the quay side is estimated to be about 20 m x 20 m, thus significantly increasing the amount of space on the quay side required for supporting the towers for loading onto the vessel. At this size, five towers arranged for loading onto a vessel would take approximately 2,000 m² of area on the quay side, which would make it difficult for all the towers to be reached by the vessel's onboard crane without moving the vessel along the quay side.

[0007] As alluded to above, another challenge with larger towers, and larger tower bases for supporting the towers, includes the size of the cranes used to load the towers onto the vessel. It is generally well known that the closer the lifting load is to the central axis of the crane, the lower the force required to lift the load. In the instant case above, if each base is about 20 m x 20 m and there are five towers arranged on the quay side in a line extending away from the water edge, then the crane will have to be sized to lift the 350- 450 tonnes at a distance of more than 90 m from the crane axis (i.e. , the last tower in the line would be at a minimum 90 m from the water edge). Lifting a load of this size and at a relatively large distance from the crane would require an extremely large crane. Such a crane may very well be beyond the capacity of many of the existing cranes on the quay side or on the vessels themselves for loading the towers onto the vessel. The alternative would be to arrange the towers along the water edge. However, this would occupy a large part of the quay, reduce the area available for the other main components, and require the vessel to move along the quay side in order to reach all the main component assemblies. Again, the large footprint of the tower stand would assist in distributing the increased load from the tower into the quay side and potentially avoid costly ground improvements. However, for the reason above, reducing the support area will provide a more efficient loading of the vessel by allowing the components to be more tightly packed.

[0008] Accordingly, there is a need for an improved system and method for handling wind turbine components, such as wind turbine towers, on the quay side that reduces the overall footprint of those components on the quay side and reduces the size of the crane required to load the components onto a vessel, but yet still provide sufficient support that will ensure that the components will not fall over under wind or other loading, and effectively transmit the load acting on the components into the ground.

Summary

[0009] To address these and other issues, an apparatus for handling wind turbine towers includes a structure coupled to the ground in a manner that supports reversible tensile and compressive loading of the structure, and a tower stand configured to be coupled to a wind turbine tower and further configured to be fixedly coupled to the structure, wherein when the tower stand, having a tower coupled thereto, is fixedly coupled to the structure, the tower is effectively coupled to the ground in a manner that supports reversible tensile and compressive loading of the tower. Normally, the reversible tensile and compressive loading of the tower generally acts in the vertical direction. In an exemplary embodiment, the structure includes a movable portion and the tower stand is configured to be fixedly coupled to the movable portion of the structure so as to allow movement of the tower on the ground.

[0010] In one embodiment, the structure includes a track coupled to the ground in a manner that supports reversible tensile and compressive loading of the track, wherein the track has a first end adjacent a water edge of the ground and a second end remote from the water edge, and a trolley coupled to the track in a manner that allows the trolley to move along the track and further coupled to the track in a manner that supports reversible tensile and compressive loading of the trolley. The tower stand may be configured to be selectively and fixedly coupled to the trolley. Moreover, the tower stand may be further configured to be selectively and fixedly coupled to the track, wherein when the tower stand, having a tower coupled thereto, is fixedly coupled to the track, the tower is effectively coupled to the ground in a manner that supports reversible tensile and compressive loading of the tower. The tower stand may be fixedly coupled to the trolley with or without the tower stand being fixedly coupled to the track, and the tower stand may be fixedly coupled to the track with or without the tower stand being fixedly coupled to the trolley.

[0011] In this regard, the apparatus may include a coupling mechanism for fixedly coupling the tower stand to the trolley. In one embodiment, the coupling mechanism includes one or more tangs associated with the trolley and movable between a first position and a second position, one or more clevises associated with the tower stand and configured to receive a respective tang, and a pin insertable through bores of the one or more clevises and the one or more tangs to achieve the fixed coupling. The apparatus may also include a locking mechanism for fixedly coupling the tower stand to the track. In one embodiment, the locking mechanism includes one or more locking pins associated with the track and movable between a first position and a second position, and one or more pin receptacles associated with the tower stand and configured to receive a respective locking pin therein.

[0012] In an exemplary embodiment, the apparatus further includes a drive mechanism for moving the trolley along the track. In one embodiment, the drive mechanism may include a rack-and-pinion arrangement. More specifically, the track may include one or more racks and the trolley may include one or more driven gears that interact with the rack to move the trolley along the track. In one embodiment, the track may include a pair of rails arranged in generally parallel relationship to each other. The track, such as the rails, may be coupled to the ground by a plurality of piles that support the track under reversible tensile and compressive loading. When the tower stand is fixedly coupled to the trolley, the tower stand is configured to slide along the track, such as on the upper surface of the rails, with movement of the trolley along the track.

[0013] In a further aspect of the invention, the apparatus may further include a frame configured to be fixedly coupled to a deck of a vessel in a manner that supports reversible tensile and compressive loading of the frame. The frame is further configured to be selectively and fixedly coupled to the tower stand, wherein when the tower stand, having a tower coupled thereto, is fixedly coupled to the frame, the tower is effectively coupled to the vessel in a manner that supports reversible tensile and compressive loading of the tower. In one embodiment, the frame includes a locking mechanism for fixedly coupling the tower stand to the frame, wherein the locking mechanism includes one or more locking pins associated with the frame and movable between a first position and a second position, and one or more pin receptacles associated with the tower stand and configured to receive a respective locking pin therein.

[0014] In another embodiment, an apparatus for handling wind turbine towers for transport to an off-shore installation site includes a track coupled to the quay side in a manner that supports reversible tensile and compressive loading of the track, wherein the track has a first end adjacent a water edge of the quay side and a second end remote from the water edge; a trolley coupled to the track in a manner that allows the trolley to move along the track and further coupled to the track in a manner that supports reversible tensile and compressive loading of the trolley when coupled to the track; and a tower stand configured to be coupled to a wind turbine tower and further configured to be selectively and fixedly coupled to the trolley, wherein when the tower stand, having a tower coupled thereto, is fixedly coupled to the trolley, the tower is effectively coupled to the quay side in a manner that supports reversible tensile and compressive loading of the tower.

[0015] In yet another embodiment, a method for handling wind turbine towers for transport to an off-shore installation site includes: i) coupling a tower stand to a wind turbine tower; ii) fixedly coupling the tower stand to a trolley movably coupled to a track, wherein the track includes a first end adjacent a water edge of a quay side and a second end remote from the water edge, the track being coupled to the quay side in a manner that supports reversible tensile and compressive loading of the track, and the trolley coupled to the track in a manner that supports reversible tensile and compressive loading of the trolley; and iii) moving the trolley along the track to move the tower toward the first end of the track. The method may further include: iv) fixedly coupling the tower stand to the track in a manner that supports reversible tensile and compressive loading of the tower. These steps, i.e., steps i)-iii) or steps i)-iv), may be repeated for additional wind turbine towers to provide a plurality of towers positioned adjacent the first end of the track. In one embodiment, the plurality of towers may be serially arranged so as to extend away from the water edge. Additionally, in one embodiment, the same trolley may be used to move each of the towers in the plurality of towers adjacent the first end of the track. [0016] In a further aspect of the invention, the method may further include: v) removing the tower from the track; vi) removing the tower stand from the track; and vii) loading the tower onto a vessel. In one embodiment, the tower stand remains coupled to the tower when the tower is removed from the track such that removal of the tower from the track also removes the tower stand. In this embodiment, loading the tower onto the vessel further comprises coupling the tower to the vessel using the tower stand. When there are a plurality of towers on the quay side for loading onto the vessel, the method may further include moving the next tower in the plurality of towers toward the first end of the track and repeating steps v)-vii) on the next tower. These steps may be repeated until all of the towers in the plurality of towers are loaded onto the vessel.

[0017] In another embodiment, an apparatus for handling wind turbine towers for transport to an off-shore installation site includes a structure configured to be coupled to a quay side in a manner that supports reversible tensile and compressive loading of the structure; a frame configured to be coupled to a deck of a vessel; and a tower stand configured to be coupled to a wind turbine tower and further configured to be selectively coupled to the structure on the quay side and further configured to be selectively coupled to the frame on the deck of the vessel. In one embodiment, when the tower stand, having a tower coupled thereto, is coupled to the structure, the tower is effectively coupled to the quay side in a manner that supports reversible tensile and compressive loading of the tower. Moreover, when the tower stand, having a tower coupled thereto, is coupled to the frame, the tower is effectively coupled to the vessel in a manner that supports reversible tensile and compressive loading of the tower. In one embodiment, the structure includes a movable portion, wherein the tower stand is configured to be coupled to the movable portion of the structure so as to allow movement of the tower on the quay side.

[0018] In still another embodiment, a method for loading a plurality of wind turbine towers onto a vessel for transport to an off-shore installation site includes: i) serially arranging a plurality of towers on a quay side adjacent a water edge; ii) loading the tower closest to the water edge onto the vessel; iii) moving the next tower in the plurality of towers closest to the water edge; and iv) repeating steps ii) and iii) until each of the towers in the plurality of towers has been loaded onto the vessel. In one embodiment, serially arranging the plurality of towers on the quay side further includes serially arranging the towers on a track coupled to the quay side, each of the towers being movable along the track. In this embodiment, moving the next tower closer to the water edge further includes moving a trolley coupled to the next tower along the track toward the water edge.

Brief Description of the Drawings

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various embodiments of the invention and, together with a general description of the invention given above and the detailed description of the embodiments given below, serve to explain the embodiments of the invention. [0020] Fig. 1 is a diagrammatic perspective view of an off-shore wind turbine;

[0021] Fig. 2 is a perspective view of a portion of a handling system for wind turbine towers on the quay side in accordance with one embodiment of the invention;

[0022] Fig. 3 is a partial perspective view of a track of the handling system in accordance with one embodiment of the invention;

[0023] Fig. 4 is another partial perspective view of a track of the handling system in accordance with one embodiment of the invention;

[0024] Fig. 5 is a partial perspective view of a trolley of the handling system in accordance with one embodiment of the invention;

[0025] Fig. 6 is a partial cross-sectional view of a drive mechanism for the handling system in one embodiment of the invention;

[0026] Fig. 7 is a partial perspective view of the handling system illustrating a tower stand coupled to the trolley in accordance with one embodiment of the invention;

[0027] Fig. 8 is a partial cross-sectional view of the handling system illustrated in Fig. 7;

[0028] Fig. 9 is a partial perspective view of a coupling mechanism for coupling a tower stand to a trolley in accordance with one embodiment of the invention;

[0029] Fig. 10 is a partial perspective view of a locking mechanism for coupling a tower stand to a track in accordance with one embodiment of the invention; and [0030] Fig. 1 1 is a diagrammatic perspective view of use of the handling system in accordance with one embodiment of the invention.

Detailed Description

[0031] With reference to Fig. 1 , an off-shore wind turbine 10 includes a foundation 12 which extends into the water, a tower 14 coupled to the foundation 12 at a lower end thereof, a nacelle 16 disposed at the apex of the tower 14, and a rotor 18 operatively coupled to a generator (not shown) housed inside the nacelle 16. The foundation 12 may be a floating

foundation, or alternatively supported by the sea bed beneath the water line. In addition to the generator, the nacelle 16 houses miscellaneous components required for converting wind energy into electrical energy and various components needed to operate, control, and optimize the performance of the wind turbine 10. The tower 14 supports the load presented by the nacelle 16, the rotor 18, and other components of the wind turbine 10 that are housed inside the nacelle 16 and also operates to elevate the nacelle 16 and rotor 18 to a height above sea level at which faster moving air currents of lower turbulence are typically found.

[0032] The rotor 18 of the wind turbine 10, which is represented as a horizontal-axis wind turbine, serves as the prime mover for the

electromechanical system. Wind exceeding a minimum level will activate the rotor 18 and cause rotation in a plane substantially perpendicular to the wind direction. The rotor 18 of wind turbine 10 includes a central hub 20 and at least one blade 22 that projects outwardly from the central hub 20 at locations circumferentially distributed thereabout. In the representative embodiment, the rotor 18 includes three blades 22, but the number may vary. The blades 22 are configured to interact with the passing air flow to produce lift that causes the rotor 18 to spin generally about a longitudinal axis 24.

[0033] The wind turbine 10 may be included among a collection of similar wind turbines belonging to an off-shore wind farm or wind park that serves as a power generating plant connected by transmission lines with a power grid, such as a three-phase alternating current (AC) power grid. The power grid generally consists of a network of power stations, transmission circuits, and substations coupled by a network of transmission lines that transmit the power to loads in the form of end users and other customers of electrical utilities. Under normal circumstances, the electrical power is supplied from the generator to the power grid as known to a person having ordinary skill in the art.

[0034] Figs. 2-1 1 illustrate a handling system 30 for a wind turbine component, and more particularly a wind turbine tower 14, in accordance with an embodiment of the invention. The handling system 30 is configured to move and support wind turbine tower 14 on the quay side 32 in preparation for being transported to an off-shore installation site via a seafaring vessel 34 (Fig. 1 1 ). The handling system 30 addresses many of the problems in current systems and methods by coupling the towers to a structure coupled to the quay side in a manner that supports reversible tensile and compressive loading of the towers. The reversible tensile and compressive loading of the towers generally act in the vertical direction. By way of example, reversible tensile and compressive loading on the towers includes those loads induced by wind forces acting on the towers. More particularly, wind forces acting on the tower will induce a tensile load on the upwind side of the tower and a compressive load on the downwind side of the tower. The coupling of the towers to the structure and the coupling of the structure to the quay side allows both reversible tensile and compressive load to be supported. This is unlike exiting systems and methods which only support the towers on the quay side under compressive loads, since the tower stands only rest on the quay side but are not otherwise physically attached thereto. In an exemplary embodiment discussed below, this structure includes a track. Because the coupling of the towers to the quay side is enhanced, the size of the coupling (e.g., the base of the tower stands) does not have to be so large. Thus, the amount of space or area on the quay side for accommodating the towers in an upright position may be significantly reduced.

[0035] In addition, the structure may include a movable portion to which the towers may attach to allow the towers to be moved on the quay side. In the exemplary embodiment, the movable portion includes a trolley

arrangement, and because the trolley is movable along the track, the towers may be moved during the loading process so that each tower being lifted and loaded onto the vessel is relatively close to the central axis of the crane. In other words, when one tower (i.e., the tower closest to the water edge) is loaded onto the vessel, the remaining towers on the quay side may be moved closer to the water edge and closer to the crane. Because the distance between the crane and lifting load has been reduced by this indexing of the towers, a smaller crane may be used to load the towers onto the vessel. These and other aspects of the invention will now be described in further detail.

[0036] In reference to Figs. 2 and 4, the handling system 30 is generally positioned on the quay side 32 adjacent a body of water 36 and defining a water edge 38 at the bounds of the quay side 32. The handling system 30 includes a plurality of supports, which in an exemplary embodiment may include piles 40 substantially positioned within the ground 42 of the quay side 32 for supporting reversible tensile and compressive loads on the handling system 30 during use. Each pile 40 includes a top plate 44 and an elongate stem 46 extending away from the plate 44 and terminating at a beveled or sharpened tip 48. The elongate stem 46 further includes a generally helical thread 50 extending substantially the full length of the elongate stem 46 in one embodiment. Alternatively, the helical thread may be discontinuous and include, for example, a series of helical plates appropriately spaced along the elongate stem 46. Other configurations for the elongate stem 46 and/or thread may also be used.

[0037] The configuration of the piles 40 serves a number of functions. First, the piles 40 are configured to distribute the loads acting on the handling system 30 to the ground 42 of the quay side 32 in a generally uniform manner. Providing load distribution reduces the peak loads acting on the quay side 32, therefore reducing the amount of ground work and other support measures required on the quay side 32 for supporting the loads imposed thereon during use. Second, and as noted above, the piles 40 are configured to accommodate tensile loading on the handling system 30 (and thus the towers being handled thereby). In this regard, the helical thread 50 on the piles 40 resists pulling the piles 40 vertically out of the ground 42, therefore providing a counterforce to tensile loads acting on the handling system 30 as a result of the overturning moment from the towers 14. The helical threads 50 also support compressive loads acting on the handling system 30 as a result of the towers 14. The ability of the piles 40 to accommodate both reversible tensile and compressive loads is, at least in part, what allows the footprint of a tower stand (described below) to be reduced, thereby increasing tower density (i.e., number of towers per unit area of quay side) relative to current values. In addition, the particular configuration of the piles 40 described above may provide other benefits, such as being quick to install, not requiring excavation or spoil, not requiring concrete or cure time, having a relatively small footprint, being removable, and being a cost effective option in soft ground applications.

[0038] The piles 40 may be made of steel or other suitable materials and positioned in the ground 42 of the quay side 32 in a relatively straight forward manner. By way of example, a land vehicle, such as a swing shovel or the like (not shown), may include a rotary attachment for rotating or screwing the piles 40 into the ground 42. As illustrated in Fig. 2, in one embodiment, the piles 40 may be embedded in the ground 42 such that the top plate 44 is adjacent to the ground 42, but exposed from above the ground 42. As discussed in more detail below, the arrangement of the piles 40 on the quay side 32 may depend on the particular configuration of the handling system 30 as well as other factors. Those of ordinary skill in the art will understand how to arrange the piles 40 to adequately support the handling system 30.

[0039] As noted above, the handling system 30 includes structure coupled to the quay side 32 in a manner that supports reversible tensile and compressive loads. Accordingly, in an exemplary embodiment, the handling system 30 further includes a track 52 for supporting and guiding the movement of a trolley 54 which, in turn, is configured to be coupled to an upright tower 14 (see Figs. 4, 5, 7 and 1 1 , for example). In an exemplary embodiment, the track 52 includes a pair of rails 56, 58 arranged in generally parallel relationship to each other, with each rail 56, 58 having a first end 60 adjacent the water edge 38 and a second end (not shown) located some distance away and remote from the water edge 38 (Figs. 4 and 1 1 ). The second end of the rails 56, 58 may be located within a warehouse, assembly facility or other structure, and/or located adjacent an uprighting station for moving sections of a tower 14 from a generally horizontal position to a generally vertical position (not shown) and assembling them into a complete tower 14. In any event, the track 52 should have a longitudinal extent such that the handling system 30 may accommodate several towers 14 in an upright position, such as, for example, four or five towers for loading onto the vessel 34. While the track 52 is illustrated as being generally linear, the track 52 may have other configurations and is therefore not limited to the generally linear arrangement as shown herein.

[0040] In an exemplary embodiment, and as illustrated in Figs. 3 and 4, each rail 56, 58 includes a plurality of rail sections 56a, 58a serially arranged in an end-to-end relationship to collectively form the rails 56, 58. In an exemplary embodiment, the rails sections 56a, 58a are generally identical so that the rails 56, 58 may be generally modular such that the rails may be handled and transported by road, rail or vessel in a relatively easy and straight forward manner. As best illustrated in Figs. 3 and 8, each rail section (described in reference to rail section 56a) has a generally I-beam profile including a top plate 62, a bottom plate 64, and a central web 66 extending therebetween. The top plate 62 includes an upper surface 68 and a lower surface 70. As explained in more detail below, the upper surface 68 may be configured to operate as a bearing surface for a base of a tower stand, and at least a portion of the lower surface 70 may be configured to include part of a drive mechanism for moving the trolley 54 along the track 52. In a similar manner, the bottom plate 64 includes an upper surface 72 and a lower surface 74. The lower surface 74 may be configured to confront and possibly engage the ground 42 of the quay side 32, and at least a portion of the upper surface 72 may be configured to operate as a bearing surface for the trolley 54, as explained below.

[0041] The central web 66 defines inner and outer sides of the rails 56, 58. In this regard, the portion of the rails 56, 58 on the side of the central web 66 which faces the other rail is referred to as the inner side, and the portion of the rails 56, 58 on the other side of the central web 66 which faces away from the other rail may be referred to as the outer side. As illustrated in the figures, including Fig. 8, the width of the bottom plate 64 is greater than the width of the top plate 62 such that the inner and outer edges of the bottom plate 64 are outboard of the respective inner and outer edges of the top plate 62.

Additionally, the inner edge 76 of the bottom plate 64 includes a lip 78 extending upward toward the top plate 62 so as to bound the bearing surface for the trolley 54. Furthermore, as illustrated in Fig. 4, the ends 80 of the rail sections 56a, 58a may include a support plate 82 on their outer side and extending between the top and bottom plates 62, 64. The rail sections 56a, 58a may also include additional support plates (not shown) between the ends 80 of the rail sections. Additionally, the support plates 82 at the ends 80 of the rail sections 56a, 58a may be used to couple the sections together (described in more detail below). Moreover, the upper surface 68 of the top plate 62 may include a bevel 84 adjacent the ends 80 of the rails sections 56a, 58a to facilitate an improved transition between adjacent rail sections.

[0042] In an exemplary embodiment, the rails 56, 58 are fixedly coupled to the piles 40 positioned in the ground 42 of the quay side 32. This fixed coupling transfers the tensile or compressive loads acting on the track 52 to the piles 40, and ultimately to the ground 42. To achieve this coupling, the bottom plate 64 of the rail sections 56a, 58a includes one or more bores 86 (e.g., two shown, one on the inner and outer sides of the rail sections). These bores 86 may be aligned with threaded bores 88 in the top plate 44 of a pile 40 and secured thereto with a suitable fastener, such as bolts 90. As illustrated in Fig. 3, each top plate 44 (but for possibly the plates at the ends of the track 52) may be coupled to ends 80 of two adjacent rail sections 56a, 58a. The invention, however, is not so limited as additional piles 40 may be coupled to rail sections 56a, 58a at other locations, such as intermediate the ends 80 (not shown). Such additional piles 40 would be determined by the support provided by the ground conditions on the quay side 32 and the number of piles 40 needed to transmit the expected loads into the ground in a safe manner. Additionally, while the handling system 30 in Fig. 4 illustrates a single track 52, it should be recognized that the handling system 30 may include a plurality of tracks (illustrated in phantom in Fig. 4, for example). Thus, there are a host of configurations for the handling system 30 that remain within the scope of the present invention.

[0043] As noted above and as illustrated in Fig. 5, the handling system 30 includes a trolley 54 movably coupled to the track 52 and further configured to be coupled to a tower 14 oriented in an upright position, as discussed below and illustrated in Fig. 1 1. Although movable along the track 52, the trolley 54 may be further coupled to the track 52 so as to support tensile and

compressive loading on the trolley 54 (e.g., the trolley 54 cannot be vertically lifted off the track 52). In one embodiment, the trolley 54 includes an undercarriage or frame 100 having a first or front slider assembly 102 and a second or rear slider assembly 104 coupled to each other by a pair of side support members 106. The front and rear slider assemblies 102, 104 each include a pair of spaced-apart slider blocks 1 10 coupled by an axle or support shaft 1 12. The slider blocks 1 10 have a rectangular box-like configuration with a lower surface 1 14 that slidingly engages the upper surface 72 of the bottom plate 64 of the rails 56, 58 outward of the lip 78, but inward of the inner edge 1 16 of the top plate 62. The slider blocks 1 10 have a height selected so as not to interfere with movement of the trolley 54 along the track 52 (and to slide underneath the tower stand as described below). For example, in an exemplary embodiment, an upper surface 1 18 of the slider blocks 1 10 may be even with or slightly below the upper surface 68 of the top plate 62. In any event, in the exemplary embodiment, the trolley 54 is configured to slide along the rails 56, 58. In an alternative embodiment, however, the trolley 54 may include wheels or tracks for rolling along the track 52. Thus, other

arrangements for movably coupling the trolley 54 to the track 52 are possible. The trolley 54 may be made from any suitable material for accommodating the loads acting thereon during use. This may include, for example, steel, suitable metals, or other materials capable of handling the loads thereon.

[0044] The handling system 30 may further include a drive mechanism, generally shown at 126, for moving the trolley 54 along the track 52. In an exemplary embodiment, the drive mechanism 126 may include a rack-and- pinion arrangement. In this regard and as illustrated in Fig. 6, at least one of the slider blocks 1 10 may include a pinion or driven gear 128 having teeth 130 that mesh with teeth 132 of a rack 134 fixedly coupled to the track 52. In one embodiment, for example, the rack 134 may be coupled to the lower surface 70 of the top plate 62 of one or both of the rails 56, 58 and on the inner side thereof. This is but one embodiment and the racks 134 may have other positions in various alternative embodiments. Accordingly, when the gear 128 is rotated in a first rotational direction, the trolley 54 moves along the track 52 in a first direction (e.g., in a forward direction). Similarly, when the gear 128 is rotated in a second, opposite rotational direction, the trolley 54 moves along the track 52 in a second direction opposite the first direction (e.g., the reverse direction). The gear 128 may be coupled to a suitable motor, such as an electric, pneumatic, or hydraulic motor, or other suitable force generator configured to rotate gear 128. The motor or device for driving the gear 128 may be located within the slider block 1 10 or otherwise coupled to the slider block or frame 100 and operatively coupled to the gear 128 for causing rotation thereof.

[0045] In the embodiment shown in the figures, each of the slider blocks 1 10 may include a driven gear 128 that meshes with a rack 134 on each of the rails 56, 58. Other arrangements, however, may be possible. For example, in one embodiment, only the slider blocks 1 10 in the front slider assembly 102 include a driven gear 128. In an alternative embodiment, only the slider blocks 1 10 in the rear slider assembly 104 include a driven gear 128. Other arrangements of the gear 128 and rack 134 may also be possible. In addition to these, additional alternative embodiments may include a different drive mechanism. For example, in another embodiment, instead of the trolley 54 being self-powered, as in the embodiment described above, the handling system 30 may include a drive mechanism separate from the trolley 54, but operatively coupled thereto for causing movement of the trolley 54 along the track 52. By way of example, the handling system 30 may include a winch having a rotatable drum and a cable wound about the drum, the cable having an end coupled to the trolley 54 such that activation of the winch (and thus rotation of the drum), causes movement of the trolley 54 along the track.

[0046] Additionally, while in the exemplary embodiment, the drive mechanism 126 provides the coupling of the trolley 54 to the track 52 so as to support the reversible tensile and compressive loads thereon, it should be recognized that the trolley 54 may have other structures (e.g., tabs, lips, etc.) for interacting with the rails 56, 58 so that the trolley 54 supports reversible tensile and compressive loads. Thus, aspects of the present invention should not be limited to the particular drive mechanism and arrangement shown and described herein.

[0047] As illustrated in Figs. 7 and 8, the handling system 30 may include a tower stand 140 having a base 142 which may be selectively and fixedly coupled to the trolley 54, and may additionally be selectively and fixedly coupled to the track 52, as will be explained below. The base 142 includes a generally rectangular or square plate having an upper surface 144, a lower surface 146, a front edge 148, a rear edge 150 and side edges 152, 154. The side edges 152, 154 include depending flanges 156, 158, respectively. The base 142 is sized such that the depending flanges 156, 158 are outboard of the top plate 62 of the rails 56, 58 and the lower surface 146 of the base 142 slidingly engages the upper surface 68 of the top plate 62. Although not shown, the upper surface 68 of the top plate may include a lubrication layer or a low-friction bearing material to facilitate sliding movement of the tower stand 140 along the track 52. Additionally, sufficient lubrication or a bearing material may also be supplied between the flanges 156, 158 and the edges of top plate 62. In this way, the loads imposed on the base 142 due to the tower 14 (discussed below) may be transferred to the track 52 and then to the ground 42 via the piles 40. As shown in Fig. 7, the tower stand 140 includes a tower connector 160 for coupling the stand 140 to the lower end of the tower 14. For example, the tower connector 160 may be configured to couple with the tower flange (not shown) at the lower end of the tower 14, through bolting, for example. In any event, the tower connector 160 is configured to fixedly couple the tower 14 to the base 142 of the tower stand 140 in a manner similar to that of current systems and methods.

[0048] In accordance with one aspect of the invention, the upright towers 14 are movable along the track 52 so that the towers 14 may be positioned or re-positioned on the quay side in a certain manner. To this end, the tower stands 140, and more particularly, the bases 142 thereof, are configured to be selectively and fixedly coupled to the trolley 54 for movement along the track 52. In this regard, the handling system 30 may include a coupling mechanism 166 for fixedly coupling the tower stand 140 to the trolley 54. In one embodiment, the coupling mechanism 166 may include one or more first connecting members 168 on the trolley 54 and one or more second connecting members 170 on the tower stand 140 that cooperate to selectively and fixedly couple the tower stand 140 to the trolley 54. In an exemplary embodiment, the second connecting member 170 may include a clevis 172 fixedly coupled to the tower stand 140 and having generally aligned bores 174. For example, the tower base 142 may include four clevises 172, two on the front edge 148 and two on the rear edge 150. In this embodiment, the clevises 172 may be located adjacent the side edges 152, 154 so as to be generally aligned with the slider blocks 1 10 of the trolley 54 when the trolley 54 is disposed beneath the tower stand 140. This also locates the connection close to the center line of the reaction of the drive mechanism (e.g., the rack and pinion arrangement). Other arrangements of the clevises 172 on the tower stand 140 may also be possible.

[0049] In an exemplary embodiment, the first connecting member 168 may include a tang 176 coupled to the trolley 54 and having a bore 178

therethrough. In one embodiment, the tangs 176 may be associated with the slider blocks 1 10 and may be movably coupled thereto. In this regard, for example, the tangs 176 may be operatively coupled to actuators 180, which are, in turn, coupled to the slider blocks 1 10. The actuators 180 may be configured to move the tangs 176 between a first extended position (Fig. 9) wherein the tangs 176 are configured to be coupled to the clevises 172 on the tower base 142, and a second retracted position (not shown) wherein the tangs 176 are out of the way and allow the trolley 54 to be moved underneath a tower stand 140, for example, without the tangs 176 contacting or otherwise interfering with the tower stand 140. With the tangs 176 in the extended position and the bores 174, 178 aligned, a pin 182 or other suitable fastener may be inserted therethrough to fixedly couple the tower stand 140 to the trolley 54. Accordingly, movement of the trolley 54 provides a corresponding movement of the tower stand 140 and the tower 14 coupled thereto. Of course, to uncouple the tower stand 140 from the trolley 54, the pins 182 may be removed from the bores 174, 178. The tangs 176 may additionally be moved to their retracted position so as not to interfere with the tower stand 140. The coupling mechanism described above is but one exemplary embodiment for fixedly coupling the tower stand 140 to the trolley 54. It should be recognized that other coupling mechanisms may be used to fixedly couple the tower stand 140 to the trolley 54 and remain within the scope of the invention.

[0050] A method of using the handling system 30 in accordance with an embodiment of the invention will now be described in further detail. Recall that for efficient loading of the vessel 34, it is desirable to provide a plurality of main component assemblies positioned adjacent the water edge 38, with the towers in a generally upright position. This arrangement typically includes a plurality of towers serially arranged to form a tower line extending away from the water edge 38 (Fig. 1 1 ). As described above, the towers 14 may be formed from a plurality of tower sections and those sections may be assembled quay side or near quay side to form the towers 14. Subsequent to this, or during the assembly of the tower 14, the lower most end of the tower 14 may be fixedly coupled to the tower stand 140 to form a tower/tower stand assembly. The tower/tower stand assembly 14 may then be operatively coupled to an assembly crane, winch or other lifting apparatus (not shown) so as to be in a generally vertical orientation with the tower stand 140 at the lower most end of the assembly.

[0051] The crane may then move the tower/tower stand assembly adjacent the second end of the track 52, which may include a trolley 54 movably coupled thereto as described above. As illustrated in Fig. 9, the assembly may then be lowered so that the base 142 of the tower stand 140 is generally positioned over the trolley 54 such that the bores 174, 178 of the clevises 172 and tangs 176 (in an extended position) are aligned. The pins 182 may then be inserted therethrough to fixedly couple the tower stand 140 to the trolley 54. As illustrated in Figs. 7 and 8, when so coupled, the lower surface 146 of the base 142 engages the upper surface 68 of the top plate 62 of the rails 56, 58 such that the upper surface 68 operates as a bearing surface for supporting a substantial portion, if not all, of the weight of the tower 14. As noted above, this load is distributed through the rails 56, 58, to the piles 40, and ultimately to the ground 42 of the quay side 32.

[0052] Moreover, when the tower stand 140, having a tower 14 coupled thereto, is fixedly coupled to the trolley 54, the tower 14 is effectively or indirectly coupled to the quay side 32 in a manner that supports reversible tensile and compressive loading of the tower 14, such as from wind forces or the like. This ability to support reversible tensile and compressive loading on the tower 14 is due, at least in part, by the manner in which the trolley 54 is coupled to the track 52 and the manner in which the track 52 is coupled to the quay side 32.

[0053] While that above describes the coupling of a tower 14 to the track 52 in accordance with an exemplary embodiment, there may be alternative methods for coupling a tower to the track 52 for movement therealong. For example, in an alternative embodiment, the tower stand 140 may be fixedly coupled to the track 52 (such as described below and without being coupled to a trolley 54) and the tower 14 subsequently assembled on the tower stand 140 using the assembly crane adjacent the second end of the track 52. Once the tower 14 is assembled on the tower stand 140, which is coupled to the track 52, the trolley 54 may then be coupled to the tower stand 140 so as to move the tower 14 along the track 52. In a further alternative embodiment, the trolley 54 may already be coupled to the tower stand 140 when the tower 14 is being assembled thereon. This may eliminate the need to provide a mechanism for securing the tower stand 140 to the track 52 independent of the trolley 54 at least at the second end of the track 52.

[0054] In any event, with the tower 14 coupled to the trolley 54 as described above, the trolley 54 may then be actuated so as to move along the track 52 from the second end and toward the first end 60 of the track 52. In this regard, the motor or other actuators (not shown) on the trolley 54 may be activated to rotate the drive gears 128, which, in turn, interact with the rack 134 on the rails 56, 58 to move the trolley 54 along the track 52. As the trolley 54 moves, the base 142 of the tower stand 140 slides along the upper surface 68 of the rails 56, 58. Additionally, the slider blocks 1 10 of the trolley 54 may slide along the upper surface 72 of the bottom plate 64 of the rails 56, 58, as illustrated in Fig. 8, for example. The trolley 54 may be moved along the track 52 until the tower 14 is adjacent the water edge 38 at the first end 60 of the track 52. At this point and in one embodiment, the trolley 54 may be uncoupled from the tower stand 140. To this end, the pins 182 may be removed from the bores 174, 178 of the clevises 172 and tangs 176, and the tangs 176 moved to their retracted position so as to avoid interference with movement of the trolley 54. However, for reasons described below, before the tower stand 140 and the trolley 54 are uncoupled, the tower stand 140 may be fixedly coupled to the track 52.

[0055] While the tower stand 140 is coupled to the trolley 54, the loads presented by the tower 14, including both the weight of the tower and the wind loads acting on the tower, are ultimately distributed and transferred to the ground 42 of the quay side 32. Additionally, and in accordance with one aspect of the invention, the fixed coupling of the tower stand 140 to the trolley 54, the particular coupling of the trolley 54 to the track 52, and the particular coupling of the track 52 to the quay side 32 allows the tower 14 to be supported under both reversible tensile and compressive loading. However, when the tower stand 140 is uncoupled from the trolley 54, then the tower 14 is essentially being supported only under compressive loading, but not under tensile loading, as there is no mechanism that restricts the upward movement of the tower 14 off the track 52 (e.g., the tower and tower stand are simply resting on the track). This situation is similar to current systems and would require a relatively large tower stand to prevent the towers from falling over under load, as discussed above.

[0056] To address this shortcoming, and in accordance with an additional aspect of the invention, the tower stand 140 may be configured to be selectively and fixedly coupled to the track 52. In an exemplary embodiment, this coupling to the track 52 is achieved before the tower stand 140 is uncoupled from the trolley 54. In this way, and because the track 52 (e.g., rails 56, 58) is fixedly coupled to the ground 42 via the piles 40, the fixed coupling of the tower stand 140 to the track 52 and the particular coupling of the track 52 to the quay side 32 allows the tower 14, once again, to be effectively or indirectly coupled to the quay side 32 in a manner that supports reversible tensile and compressive loading of the tower 14. In other words, it may be desirable to always have the towers arranged in a manner that supports reversible tensile and compressive loading. To achieve the coupling of the tower stand 140 to the track 52, the handling system 30 may include a locking mechanism 188. In one embodiment, the locking mechanism 188 may include one or more locking pins 190 coupled to one or both of the rails 56, 58 at certain locations. As illustrated in Figs. 8 and 10, the locking pins 190 may be coupled to the outer side of the rails 56, 58 and adjacent the intersection of the central web 66 and the top plate 62. Other positions, however, may be possible.

[0057] The locking pins 190 are configured to be movable between an extended state (Fig. 8) and a retracted state (Fig. 10) such as by being coupled to suitable actuators. In the extended state, the locking pins 190 are configured to be received within pin receptacles in the base 142 of the tower stand 140. More particularly, in one embodiment, the depending flanges 156, 158 of the base 142 may include a plurality of bores 192 along the length thereof configured to receive a locking pin 190 therein. When one or more of the locking pins 190 engage a bore 192 on the tower stand 140, the tower stand 140 is fixedly coupled to the track 52. In a preferred embodiment, a plurality of locking pins 190 may be configured to engage bores 192 of a tower stand 140 when it is desired to couple the tower stand 140 to the track 52. In the retracted position, the locking pins 190 are configured to be out of the way of the tower stand 140, and the tower stand 140 is free to move along the track 52 without interference from the pins 190.

[0058] Accordingly, in the method described above, once the tower 14 has been moved to its desired position adjacent the first end 60 of the track 52, prior to uncoupling the trolley 54 from the tower stand 140, the locking pins 190 on the track 52 may be actuated so as to engage with the bores 192 in the tower stand 140 to fixedly couple the tower stand 140, and thus the tower 14, to the track 52. With the first tower positioned adjacent the water edge 38, the trolley 54 may then be moved along the track 52 back toward the second end of the track 52 and the process, as described above, repeated so that a plurality of towers 14 are serially arranged adjacent the water edge 38 for loading onto the vessel 34. The number of towers 14 lined up and ready for loading may depend on various parameters, including the number of wind turbines 10 to be installed on the site, the size of the vessel 34, or other factors. In an exemplary embodiment, four or five towers 14 may be lined up on the track 52 adjacent the water edge 38.

[0059] It should be recognized that the method described above is merely one exemplary method for providing an arrangement of towers 14 for loading onto the vessel 34. There may be alternative methods for providing a plurality of towers 14 adjacent the water edge 38 for loading onto a vessel 34 within the scope of the invention. For example, the method described above included one trolley 54 on the track 52 for moving the towers 14 toward the first end 60 of the track 52. In an alternative embodiment, the method may employ additional trolleys 54 for moving the towers 14.

[0060] The handling system 30 as described above addresses at least some of the deficiencies of existing systems for handling wind turbine towers on the quay side. In this regard, the handling system 30 provides a fixed coupling of the tower 14 to the ground 42 of the quay side 32 in a manner that supports both reversible tensile and compressive loading of the tower. In current systems, towers are supported on the quay side in a manner that only supports compressive loads. By providing a positive coupling of the tower stand 140 to the ground 42 of the quay side 32 (via the trolley 54, track 52 and piles 40, for example), the tower stands 140 may be reduced in size as compared to current systems. This, in turn, allows the towers 14 on the quay side 32 to be packed together more tightly. As described above, for a 90-100 m tower, it is estimated that tower stands on the order of 20 m x 20 m must be used to prevent the towers from falling over. For an arrangement of five serially aligned towers, for example, the tower density is estimated to be about 0.0025 towers/m². In the handling system 30 in accordance with the present invention, it is estimated that a 90-100 m tower may have a tower stand 140 with a size on the order of 8 m x 8 m. With a similar arrangement of towers, the tower density using the handling system 30 is estimated to be about 0.0156 towers/m², which represents over a 600% increase in the tower density. Accordingly, the amount of space on the quay side 32 taken up by the towers 14 has significantly improved as a result of the handling system 30.

[0061] In addition to the above, the handling system 30 also addresses other shortcomings of existing systems and methods. As illustrated in Fig. 1 1 , when it comes time to load the towers 14 onto the vessel 34, a crane 200 or other lifting apparatus on or adjacent the vessel 34 may be coupled to the first tower 14a in the line of plurality of towers. Once coupled to the crane 200, the locking mechanism 188 may be actuated to move the locking pins 190 to their retracted position and disengage the locking pins 190 from the bores 192 in the tower stand 140a. The crane 200 may then lift the tower 14a and its associated tower stand 140a off the track 52 and onto the vessel 34.

Maintaining the tower stand with the tower avoids the time and labor associated with disconnecting the tower from the tower stand, as is the current approach, thereby saving significant time. Additionally, and as discussed below, the tower stand 140a may be used to couple the tower 14a to the vessel 34. The manner in which the tower 14a is coupled to the vessel 34 is discussed below.

[0062] As further illustrated in Fig. 1 1 , this leaves a void 202 in the track 52 adjacent the water edge 38. In accordance with an aspect of the invention, the trolley 54 may be coupled to the second tower 14b in the plurality of towers, such as in the manner described above, so as to move the second tower 14b forward along the track 52 toward the first end 60 and closer to the water edge 38. When the second tower 14b has been moved to the first end 60 of the track 52, the tower stand 140b may be locked to the track 52 in the manner described above and the trolley 54 may be uncoupled from the tower stand 140b of the second tower 14b. In one embodiment, the process of moving the second tower 14b to the first end 60 of the track 52 may be performed as the crane 200 is loading the first tower 14a. The crane 200 may then be coupled to the second tower 14b. Similar to above, the locking mechanism 188 may be actuated to move the locking pins 190 to their retracted position and disengage the locking pins 190 from the bores 192 in the second tower stand 140b. The crane 200 may then lift the second tower 14b and its associated tower stand 140b off the track 52 and onto the vessel 34. This process may then be repeated until all of the towers 14 in the arrangement of plurality of towers have been moved forward to the first end 60 of the track 52 and loaded onto the vessel 34.

[0063] The benefit of this method is that the lifting performed by the crane 200 so as to load the towers 14 onto the vessel 34 is done in relatively close proximity to the crane axis 204, therefore minimizing the size of crane required to load the towers 14 onto the vessel 34. Accordingly, as wind turbines increase in size and weight, the handling system 30 as described herein may allow existing cranes on vessels or on the quay side adjacent the vessels to be used to load the larger and heavier components. This, of course, will obviate the costs associated with purchasing, installing, and operating larger and higher capacity cranes on the vessels or quay side capable of lifting the larger components.

[0064] In a further aspect of the present invention, various components of the handling system 30 may be used to improve the apparatus and method of transporting the towers 14 on the vessel 34. In this regard, it should be noted that in accordance with an embodiment of the invention, the tower stand 140 is removed from the track 52 when the towers 14 are loaded onto the vessel 34 (see Fig. 1 1 ). In this aspect of the invention, these tower stands 140 may be used in an advantageous manner on the vessel 34. In this regard, and in reference to Fig. 1 1 , the vessel 34 may include a plurality of frames 206 (one shown) configured to be fixedly coupled to the deck 208 of the vessel 34, such as through welding, bolting, or the use of other fasteners or techniques. For example, in one embodiment, the frames 206 may include a latticework of beams 210. In one embodiment, the frames 206 may be fixedly coupled to the vessel 34 in a manner that supports reversible tensile and compressive loading of the frame 206 due to wind loads and the motion of the vessel 34 while in transit to the installation site.

[0065] In an exemplary embodiment, the frames 206 may be sized so as to fit within the bounds of the base 142 of the tower stands 140 such that the lower surface 146 of the base 142 engages an upper surface 212 of the frame 206. Frames 206 may include a locking mechanism for selectively and fixedly coupling the tower stands 140 to the frames 206. For example, in one embodiment, the frames 206 include one or more locking pins 214 coupled thereto which are configured to be movable between an extended state and a retracted state. In the extended state, the locking pins 214 are configured to be received within the bores 192 in the depending flanges 156, 158 of the base 142 of the tower stand 140. When one or more of the locking pins 214 engage a bore 192 on the tower stand 140, the tower stand 140 is fixedly coupled to the frame 206, which, in turn, is fixedly coupled to the deck 208 of the vessel 34. When so coupled, the tower 14 is supported on the vessel 34 under both reversible tensile and compression loading of the towers. With the towers 14 so secured to the vessel 34, the towers 14 may be transported to the installation site of the wind turbine. In the retracted position, the locking pins 214 are configured to be out of the way of the tower stand 140 such that the tower stand 140 may be moved downwardly onto and over the frame 206 (or removed therefrom). Thus, in accordance with an embodiment of the invention, the tower stands 140 used in the handling system 30 on the quay side 32 may also be used to support the towers 14 on the vessel 34.

[0066] While the embodiment above had the tower stands 140 remain coupled to the towers 14 during removal of the towers 14 from the track 52, the invention is not so limited. In an alternative embodiment, when the crane 200 loads a tower 14 onto the vessel 34, its associated tower stand 140 may remain on the track 52. Thus, in order to index the second tower (and any remaining towers) forward, an auxiliary lifting device (not shown), such as a relatively small land-based mobile crane or the like, may remove the tower stand 140 from the track 52 and allow the next tower 14 to be moved forward. In this way, the method of indexing the towers 14 forward for loading onto the vessel 34 may still be executed even though the tower stands 140 are not being used to couple the towers 14 to the vessel 34.

[0067] While the invention has been illustrated by a description of various embodiments and while these embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. For example, while aspects of the invention have been described with the tower stand being separable from the trolley, in an alternative embodiment, the tower stand may be inseparably coupled to the trolley and the lower end of the tower may be coupled thereto so as to couple the tower to the trolley. Moreover, while aspects of the invention have been described as being used on the quay side for off-shore applications, aspects of the invention may be used to handle wind turbine main component assemblies in manufacturing and/or storage facilities for on-shore applications as well. Thus, the invention in its broader aspects is therefore not limited to the specific details, representative methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the general inventive concept.

What is claimed is:

Claims

1. An apparatus for handling wind turbine towers, comprising: a structure coupled to the ground in a manner that supports reversible tensile and compressive loading of the structure; and

a tower stand configured to be coupled to a wind turbine tower and further configured to be fixedly coupled to the structure,

wherein when the tower stand, having a tower coupled thereto, is fixedly coupled to the structure, the tower is effectively coupled to the ground in a manner that supports reversible tensile and compressive loading of the tower.

2. The apparatus according to claim 1 , wherein the structure includes a movable portion, the tower stand configured to be fixedly coupled to the movable portion of the structure so as to allow movement of the tower on the ground.

3. The apparatus according to claim 2, wherein the structure comprises:

a track coupled to the ground in a manner that supports reversible tensile and compressive loading of the track, the track having a first end adjacent a water edge of the ground and a second end remote from the water edge; and the movable portion includes a trolley coupled to the track in a manner that allows the trolley to move along the track and further coupled to the track in a manner that supports reversible tensile and compressive loading of the trolley, the tower stand configured to be selectively and fixedly coupled to the trolley.

4. The apparatus according to claim 3, wherein the tower stand is further configured to be selectively and fixedly coupled to the track, wherein when the tower stand, having the tower coupled thereto, is fixedly coupled to the track, the tower is effectively coupled to the groundin a manner that supports reversible tensile and compressive loading of the tower.

5. The apparatus according to claim 4, wherein the tower stand is configured to be fixedly coupled to the trolley with or without the tower stand being fixedly coupled to the track, and the tower stand is configured to be fixedly coupled to the track with or without the tower stand being fixedly coupled to the trolley.

6. The apparatus according to any of claims 3-5, further comprising a coupling mechanism for fixedly coupling the tower stand to the trolley.

7. The apparatus according to claim 6, wherein the coupling mechanism includes one or more tangs associated with the trolley and movable between a first position and a second position, one or more clevises associated with the tower stand and configured to receive a respective tang, and a pin insertable through bores of the one or more clevises and the one or more tangs.

8. The apparatus according to any of claims 4-8, further comprising a locking mechanism for fixedly coupling the tower stand to the track.

9. The apparatus according to claim 8, wherein the locking mechanism includes one or more locking pins associated with the track and movable between a first position and a second position, and one or more pin receptacles associated with the tower stand and configured to receive a respective locking pin therein.

10. The apparatus according to any of claims 3-9, further comprising a drive mechanism for moving the trolley along the track.

1 1. The apparatus according to claim 10, wherein the drive mechanism includes a rack-and-pinion arrangement.

12. The apparatus according to any of claims 3-1 1 , wherein the track comprises a pair of rails arranged in generally parallel relationship to each other.

13. The apparatus according to any of claims 3-12, wherein the track is coupled to the ground by a plurality of piles that support the track under reversible tensile and compressive loading.

14. The apparatus according to any of claims 3-13, wherein when the tower stand is fixedly coupled to the trolley, the tower stand is configured to slide along the track with movement of the trolley along the track.

15. The apparatus according to any of claims 1-14, further comprising a frame configured to be fixedly coupled to a deck of a vessel in a manner that supports reversible tensile and compressive loading of the frame, the frame further configured to be selectively and fixedly coupled to the tower stand, wherein when the tower stand, having the tower coupled thereto, is fixedly coupled to the frame, the tower is effectively coupled to the vessel in a manner that supports reversible tensile and compressive loading of the tower.

16. The apparatus according to claim 15, wherein the frame includes a locking mechanism for fixedly coupling the tower stand to the frame, the locking mechanism including one or more locking pins associated with the frame and movable between a first position and a second position, and one or more pin receptacles associated with the tower stand and configured to receive a respective locking pin therein.

17. An apparatus for handling wind turbine towers for transport to an off-shore installation site, comprising:

a track coupled to the quay side in a manner that supports reversible tensile and compressive loading of the track, the track having a first end adjacent a water edge of the quay side and a second end remote from the water edge;

a trolley coupled to the track in a manner that allows the trolley to move along the track and further coupled to the track in a manner that supports reversible tensile and compressive loading of the trolley when coupled to the track; and

a tower stand configured to be coupled to a wind turbine tower and further configured to be selectively and fixedly coupled to the trolley, wherein when the tower stand, having a tower coupled thereto, is fixedly coupled to the trolley, the tower is effectively coupled to the quay side in a manner that supports reversible tensile and compressive loading of the tower.

18. A method for handling wind turbine towers for transport to an offshore installation site, comprising:

i) coupling a tower stand to a wind turbine tower; ii) fixedly coupling the tower stand to a trolley movably coupled to a track, the track including a first end adjacent a water edge of a quay side and a second end remote from the water edge, the track being coupled to the quay side in a manner that supports reversible tensile and compressive loading of the track, and the trolley being coupled to the track in a manner that supports reversible tensile and compressive loading of the trolley; and

iii) moving the trolley along the track to move the tower toward the first end of the track.

19. The method according to claim 18, further comprising:

iv) fixedly coupling the tower stand to the track in a manner that supports reversible tensile and compressive loading of the tower.

20. The method according to claim 18 or 19, further comprising repeating these steps on additional wind turbine towers to provide a plurality of towers positioned adjacent the first end of the track.

21. The method according to claim 20, further comprising using the same trolley to move each of the towers in the plurality of towers positioned adjacent the first end of the track.

22. The method according to any of claims 18-21 , further comprising:

v) removing the tower from the track;

vi) removing the tower stand from the track; and

vii) loading the tower onto a vessel.

23. The method according to claim 22, wherein the tower stand remains coupled to the tower when the tower is removed from the track such that removal of the tower from the track also removes the tower stand, and loading the tower onto the vessel further comprises coupling the tower to the vessel using the tower stand.

24. The method according to claim 22 or 23 when dependent from claim 20, further comprising:

moving a next tower in the plurality of towers toward the first end of the track; and

repeating steps v)-vii) on the next tower.

25. The claim according to claim 24, further comprising repeating these steps until all of the towers in the plurality of towers are loaded onto the vessel.

26. An apparatus for handling wind turbine towers for transport to an off-shore installation site, comprising:

a structure configured to be coupled to a quay side in a manner that supports tensile and compressive loading of the structure;

a frame configured to be coupled to a deck of a vessel; and a tower stand configured to be coupled to a wind turbine tower and further configured to be selectively coupled to the structure on the quay side and further configured to be selectively coupled to the frame on the deck of the vessel.

27. The apparatus according to claim 26, wherein when the tower stand, having a tower coupled thereto, is coupled to the structure, the tower is effectively coupled to the quay side in a manner that supports reversible tensile and compressive loading of the tower.

28. The apparatus according to claim 26 or 27, wherein when the tower stand, having a tower coupled thereto, is coupled to the frame, the tower is effectively coupled to the vessel in a manner that supports reversible tensile and compressive loading of the tower.

29. The apparatus according to any of claims 26-28, wherein the structure includes a movable portion, the tower stand configured to be coupled to the movable portion of the structure so as to allow movement of the tower on the quay side.

30. A method for loading a plurality of wind turbine towers onto a vessel for transport to an off-shore installation site, comprising:

i) serially arranging a plurality of towers on a quay side adjacent a water edge; ii) loading the tower closest to the water edge onto the vessel; iii) moving the next tower in the plurality of towers closer to the water edge; and

iv) repeating steps ii) and iii) until each of the towers in the plurality of towers has been loaded onto the vessel.

31. The method according to claim 30, wherein serially arranging a plurality of towers on the quay side further comprises serially arranging the plurality of towers on a track coupled to the quay side, each of the towers being movable along the track.

32. The method according to claim 31 , wherein moving the next tower further comprises moving a trolley coupled to the next tower along the track toward the water edge.