Patent Publication Number: US-2009217852-A1

Title: Method and apparatus for transporting and mounting offshore wind generators

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to transporting and mounting wind generators onto support structures. Specifically, the present invention relates to a method and apparatus for transporting one or more wind generators from an onshore location to an offshore support structure. Moreover, the present invention provides for a method and apparatus for mounting a wind generator onto an offshore support structure. 
     2. Related Art 
     In recent years there has been an increased focus on renewable energy, with particular interest given to wind energy. Current forms of wind energy generation rely on a wind generator to harness the wind&#39;s power. Given that wind currents over open water are often stronger and more consistent, there has been a recent push to erect wind generators in open water. 
     One big hurdle which must be overcome in order for large scale offshore wind generation to become a reality is the development of an efficient means of installing wind generators in open water. Weather conditions at sea often create unpredictable and significant obstacles thereby reducing the time with which installation crews can safely work at sea. In addition, the use of cranes during the offshore installation process often has significant economic impact on the viability of an installation project. 
     Each offshore wind generator is mounted onto a support structure. Sometimes referred to as a “jacket”, a support structure is usually prefabricated at an onshore location and transported to its offshore location through use of a barge. The term “support structure” is intended to include, but is not limited to, a device capable of supporting the weight of an object, such as a wind generator. As described in  FIG. 1 , an embodiment of a support structure  100  may include one or more support legs  102  and a mounting point  104 . In some embodiments of the support structure  100 , the mounting point  104  includes a crown  106 . The crown  106  provides an area in which a mast of a wind generator can be inserted to form a friction connection between the mast of the wind generator and the support structure  100 . This friction connection may provide some or all of the force necessary to secure the wind generator to the support structure  100 . In embodiments where the crown  106  does not provide the force necessary to secure the wind generator, the wind generator will be secured through use of methods known to one skilled in the art. The form of the support structure  100  may vary however each variation will provide a solid foundation upon which a wind generator can be mounted. Examples of possible support structure forms are single mono-poles, 3 legged truss, or 4 legged truss structures. The support structures  100  may be equipped with commonly used marine fender systems in order to reduce any adverse effects caused as a result of friction between a support structure  100  and other objects, such as a water vessel. The fending system may provide a temporarily mooring means to allow a water vessel to be moored to the support structure  100 . 
     Once the barge transporting the support structure  100  has arrived at the erection site, the support structure  100  is removed from the deck of the barge and placed into the water. Removal of the support structure  100  from the deck of the barge is usually accomplished through use of a crane. The crane is capable of lifting the support structure  100  from the deck of the barge and placing it into the water. Once in the water, the support structure  100  is secured to the sea floor. The tern “sea floor” is intended to include, but is not limited to the surface at the bottom of the sea, ocean, or other body of water. In order to secure the support structure I  00  to the sea floor, the legs of the support structure  100  are mounted onto foundation piles which have been driven into the sea floor. Marine grout is utilized to secure the support structure  100  onto the foundation piles. 
     With the support structures  100  in place, the focus of constructing an offshore wind farm turns to mounting the wind generator onto the support structure  100 . Current methods of mounting a wind generator onto the support structure  100  often require the use of a crane. These cranes are used to maneuver the wind generators into a position where the wind generator can be secured onto a support structure. Given that proper alignment is critical to successfully securing a wind generator onto the support structure  100 , the crane must provide exact positioning in order to effectively mount a wind generator onto the support structure  100 . With many environmental factors at play in an open water installation project, proper alignment by a waler bound crane is often difficult and time consuming. 
     Given the need to establish an effective means of installing an offshore wind generator, highly specialized sea vessels had begun to be developed. However, current methods of installing offshore wind generators fail to meet all of the current demands required of an effective installation method. More specifically, current methods fail to provide a means of installing multiple assembled or partially assembled wind generators from a single vessel, without the aid of an offshore crane. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a method and apparatus for mounting one or more generators on support structures. In one embodiment of the present invention, two primary functions are performed: (1) transferring one or more assembled or partially assembled wind generators from and onshore location onto a water vessel, and (2) mounting the one or more assembled or partially assembled wind generators from a water vessel onto the one or more support structures. 
     According to an embodiment of the present invention, transfer of the assembled or partially assembled wind generators from onshore on a water vessel is accomplished through the use of rail guided tractors that secure the assembled or partially assembled wind generators onshore and travel along a rail system extending to a water vessel. Once the rail guided tractor has transported the wind generator onto a water vessel, the water vessel is free to travel, with the wind generator on deck, to its intended destination. 
     In an embodiment of the current invention, transfer of the wind generator from the water vessel onto the support structure  100  is accomplished by engaging the water vessel with the support structure  100  and raising the water vessel to a mounting height. With the water vessel positioned at the appropriate vertical height, the rail guided tractor positions the wind generator above the support structure  100 . The wind generator is then vertically lowered from its suspended position thereby mounting the wind generator onto the support structure  100 . Once the support mast of the wind generator has been securely mounted onto the support structure  100 , the rail mounted tractor will disengage from the support mast of the wind generator. Finally, the water vessel is returned to its floating position. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be more readily understood from the detailed description of exemplary embodiments presented below considered in conjunction with the attached drawings, of which; 
         FIG. 1  is a side view of a three legged support structure, according to an embodiment of the prior art; 
         FIG. 2  is a flow diagram of an embodiment of the present invention; 
         FIG. 3  is a perspective view of a wind generator, according to an embodiment of the present invention; 
         FIG. 4A  is a perspective view of the top portion of a transfer tractor, according to an embodiment of the present invention; 
         FIG. 4B  is a perspective view of the bottom portion of a transfer tractor, according to an embodiment of the present invention; 
         FIG. 4C  is a perspective view of a mechanism for vertically maneuvering the transfer tractor platform, according to an embodiment of the present invention; 
         FIG. 4D  is a perspective view of a transfer tractor platform configures for circular motion, according to an embodiment of the present invention; 
         FIG. 5  is a perspective view of a water vessel, according to an embodiment of the present invention; 
         FIG. 6  is a perspective view of the elements utilized in the process of transporting a wind generator from an onshore location onto a water vessel; 
         FIG. 7  is a perspective view of a water vessel engaged with a support structure, according to an embodiment of the present invention; and 
         FIG. 8  is a perspective view of a water vessel positioned at a mounting height, according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention relates to a method of transporting, from an onshore location, one or more assembled or near assembled wind generators and mounting the one or more assembled or near assembled wind generators onto one or more support structures. This is accomplished through the use of a single water vessel and without substantial aid from an offshore crane. The term “onshore” is intended to include, but is not limited to, an area of land in close proximity to a body of water. The term “offshore” is intended to include, but in not limited to, a geographic area which is surrounded by water. 
       FIG. 2  describes, in general terms, the individual steps with comprise one embodiment of the current invention.  FIG. 2  illustrates a process flow diagram for a method of transporting one or more assembled or near assembled wind generators from an onshore location and mounting the one or more assembled or near assembled wind generators onto one or more support structures at offshore locations. 
     The term “wind generator” is intended to include, but is not limited to, a device for converting wind power into electrical energy. As shown in  FIG. 3 , an embodiment of a wind generator  300  may include a support mast  302 , a plurality of rotor blades  304 , and a gearbox  306 . In addition, the term “partially assembled wind generator” is intended to include, but is not limited to, a wind generator which does not require the substantial construction to complete its assembly. From herein, unless specifically state, the term wind generator will refer to both a partially assembled wind generator as well as a wind generator that does not require additional assembly. 
     The method  200 , shown in  FIG. 2 , begins with the transport of one or more wind generators from an onshore location to a water vessel  202 . In one embodiment of the current invention, the wind generators  300  are primarily moved through use of transport units. The two most commonly used transport units are a yard tractor and transfer tractor. The term “yard tractor” is intended to include, but is not limited to, a unit capable of seizing the wind generator  300 , transporting the seized wind generator  300  to a second location, and releasing contact with the wind generator  300  at the second location while ensuring that the wind generator  300  remains erect. A yard tractor can be self propelled, propelled by an external source, or a hybrid of the two. The yard tractor is fitted with the appropriate foundation as to enables it to travel along rail segments. 
     A second type of transport unit is a transfer tractor. The term “transfer tractor” is intended to include, but is not limited to, a unit capable of seizing the wind generator  300 , transporting the seized wind generator  300  to a second location, and releasing contact with the wind generator  300 . The transfer tractor  400 , described further in  FIG. 4A and 4B , is fitted with the appropriate foundation as to enables it to travel along rail segments. In addition to being capable of traveling along rail segments, in some embodiments of the current invention, the transfer tractor  400  is capable of moving in directions not governed by a rail segment. This includes the ability to rotate in a circular motion. In some embodiments, the transfer tractor  400  may have the capability to raise and lower a wind generator  300  relative to the surface of the water. A transfer tractor  400  can be self propelled, propelled by an external source, or a hybrid of the two. 
       FIG. 4A and 4B  illustrates an embodiment of the transfer tractor  400 . The elements of the transfer tractor  400  are built around the transfer tractor platform  402 . The transfer tractor platform  402  has a top portion  404  and a bottom portion  406 . Located on the top portion  404  of the transfer tractor platform  402  is a staging layer  408 , one or more support arms  410 , and one or more attachment units  412 . The staging layer  412  acts an intermediary between the transfer tractor platform  402  and the support arms  410 . In some embodiments of the transfer tractor  400 , the staging layer  412  provides increased movement for the transfer tractor  400 . In such embodiments, the staging layer  412  is equipped for circular motion atop the transfer tractor platform  402 , thereby allowing the support arms  410  to move in a circular motion. An embodiment of the transfer tractor  400  fit for circular motion is further described in  FIG. 4D . One or more attachment units  412  are located on top of the staging layer  408 . The attachment units  412  acts as the connection point between the staging layer  408  and each individual support arm  410 . 
     In an embodiment of the transfer tractor  400  lacking the staging layer  408 , the attachment units  412  will be directly connected or integrated into the transfer tractor platform  402 . Each support arm  410  has a first end  414  and a second end  416 . The first end  414  of the support arm  410  is connected to an attachment unit  412  while the second end  416  of the support arm  410  is used as the contact point between the support arm  410  and the wind generator  300 . In the current embodiment of the transfer tractor  400 , the first end  414  of each support arm  410  is pivotally connected to an attachment unit  412 . This pivot connection secures the support arm  410  to the attachment unit  412  while providing the support arm  410  the ability to move about the pivot point. The second end  416  of the support arm  410  provides the contact point between the support arm  410  and the wind generator  300 . When the mast  302  of the wind generators  300  is in a secured position within the transfer tractor  400 , the one or more support arms  410  provide the support as to ensure that the wind generator  300  remains erect. This is accomplished through use of friction contact between the second end  416  of the support arm  410  and the mast  302  of the wind generator  300 . In embodiments where the friction connection between the second end  416  of the support arms  410  and the mast  302  of the wind generator  302  fail to provide adequate force to ensure that the wind generator  300  remains secure, additional securing means know to one skilled in the art may be used. 
     Located on the bottom portion  406  of the transfer tractor platform  402 , described in  FIG. 4B , are one or more transfer tractor rails  418  and one or more rail units  420 . The one or more transfer tractor rails  418  are rail segments secured to the bottom portion of the transfer tractor platform  402 . The one or more transfer tractor rail units  420  are slidably connected to both an onshore or water vessel rail segment, as well as, the transfer tractor rail units  418 . The slidable connection between the transfer tractor rail unit  418  and the onshore or water vessel rail segments enables the transfer tractor rail unit  418  to slide along the onshore or water vessel rail segment thereby moving the transfer tractor  400 . This movement of the transfer tractor  400  may be from a first onshore location to a second onshore location, from an onshore location to a water vessel, or from a first location on a water vessel to a second location on a water vessel. In contrast, the slidable connection between the transfer tractor rail units  420  and the transfer tractor rail segments  418  allows the transfer tractor rail units  420  to slide along the transfer tractor rail segment  418  thereby moving the transfer tractor platform  402  relative to the onshore or water vessel rail segment. This movement may be perpendicular to the onshore or water vessel rail segments. 
       FIG. 4C  illustrates an embodiment of the transfer tractor where the transfer tractor platform  402  is capable of vertical motion. The vertical motion is facilitated through the use of one or more hydraulic cylinders  422 . The hydraulic cylinders  422  arc capable of exerting the necessary force to vertically maneuver the transfer tractor platform.  402 . In addition, the hydraulic cylinders  422  are fit to vertically maneuver the transfer tractor  400  in the event that the transfer tractor  400  has seized a wind generator  300 . In the current embodiment, there is a first end of the hydraulic cylinder  424 , a second end of the hydraulic cylinder  426 , and a piston  428 . The first end of the hydraulic cylinder  424  is fixedly connected to the transfer tractor rails  418 . The second end of the hydraulic cylinder  422  is fixedly connected to the transfer tractor platform  402 . As illustrated in the embodiment in  FIG. 4C , the second end of the hydraulic cylinder  426  may be fixedly connected to the interior of the transfer tractor platform  402 . The piston  428  is slidably connected to the interior of the second end of the hydraulic cylinder  424 . As illustrated in the  FIG. 4C , in the extended position, the piston  428  slides from its location within the second end of the hydraulic cylinder  424  and therefore forces the transfer tractor platform  402  to a vertically suspended position above the transfer tractor rail segments  418 . In order to facilitate the lowering of the transfer tractor platform  402 , the piston  428  returns to its position within the second end of the hydraulic cylinder  426 , thereby causing the transfer tractor platform  402  to descend vertically. Other methods could be used to vertically maneuver the transfer tractor platform  402 . This may include the use of a rack and pinion system. Other methods know to one skilled in the art may be utilized to vertically manipulate the transfer tractor platform  402 . 
     In addition to vertical motion, the transfer tractor  400  may be capable of facilitating circular motion.  FIG. 4D  illustrates an embodiment of the transfer tractor  400 , where the staging layer  408  is capable of circular motion. In the embodiment described in  FIG. 4D , the staging layer  408  is slidably connected to the transfer tractor platform  402 , thereby enabling the staging layer  408  to rotate in a circular direction atop the transfer tractor platform  402 . The staging layer  408  and the transfer tractor platform  402  may be slidably connected through use of a dedicated sliding pad, lubricated surface, slewing bearings, or other means known to one skilled in the art. One or more stabilizers  432  are fixedly attached to the transfer tractor platform  402  in order the help secure the staging layer  408 . A portion of the edge of the staging layer  408  will be slidably secured by the one or more stabilizers  432 . The circular motion of the staging layer  408  may be powered through use of one or more hydraulic cylinders  430 . Each hydraulic cylinder  430  has a first end  434  and a second end  436 . The first end  434  is fixedly connected to the transfer tractor platform  402 , while the second end  436  is connected to the staging layer  408 . Through the expansion and contraction of the hydraulic cylinder  430 , circular motion of the staging layer  408  is initiated. This circular motion could also be facilitated through use of a rack and pinion system or other means known to one skilled in art. 
     A water vessel used in the process of transporting the wind generator  300 . The term “water vessel” is intended to include, but is not limited to, a structure which is fit for water based travel, as is known to one skilled in the art. As described in  FIG. 5 , an embodiment of the water vessel  500  may include a platform  502 , one or more retractable legs  504 , one or more pairs of water vessel rail segments  506 , and one or more staging points  508 . The water vessel  500  can be self propelled, propelled by an external source, or a hybrid of the two. The platform  502  provides the buoyancy which allows the water vessel to float. In addition, the platform  502  acts as the mounting point for other elements that make up the water vessel, such as the one or more retractable legs  504  and a pair of water vessel rail segments  506 . The one or more retractable legs  504  are used in the process of lifting the water vessel from the surface of the water. The one or more retractable legs  504  are slidably connected to the platform  502 , therefore the retractable legs  504  can travel through the body of the platform  502 . The retractable legs  504  have three primary states, upward, downward, and transition. 
     In  FIG. 5 , the retractable legs  504  are in the upward position. In the upward position, the retractable legs  504  are primarily above the deck of the platform  502 . When the retractable legs  504  are in the downward state, the retractable legs  504  are primarily below the platform  502  and have engaged with a sea floor. While in the transition state, the retractable legs  504  are in the process of moving between the upward state and downward state or vice versa. The retractable legs  504  are used as the support legs for the raised water vessel. The embodiment illustrated in  FIG. 5  also describes a platform which includes one pair of water vessel rail segments  506 . The pair of water vessel rail segments  506  is located on the deck of the platform  502  and provides a channel by which objects can travel. The pair of water vessel rail segments  506  span the length of the platform  502  and are securely attached to the water vessel  500 . The platform  502  described in  FIG. 5  includes two staging points  508 . The staging points  508  provide a point at which the water vessel  500  can engage with the support structure  100 . The staging points comprise an area of water vessel  500  where a platform  502  gives way to an opening which provides a point at which the water vessel can partially surround the support structure  100 . At either end of the platform  502 , the pair of water vessel rail segments  506  straddle the staging points  508 . This configuration of having the pair of water vessel rail segments  506  straddling the staging points  508  allows for a device traveling on the water vessel rail segments  506  to position itself above the staging points  508 . When the water vessel  500  is positioned above the support structure  300 , a staging point  508  provides a point at which a device traveling on the water vessel rail segment  506  can position itself above the support structure  300 . This allows a transfer tractor  400 , carrying a wind generator  200 , to position the wind generator  200  directly above the support structure  100 . 
       FIG. 6  shows the elements employed in the process of transporting the wind generator from an onshore location onto the water vessel, as in step  202 . The wind generator  300  is first transported to a transfer support  602 . The transfer support  602  is a means configured to maintain a wind generator  300  in an upright position. The transfer support  602  is utilized to facilitate transfer of the wind generator  300  from one transport unit to another. 
     A yard tractor  604  shown in  FIG. 6  will transport the wind generator  300  to the transfer support  602 . The yard tractor  604  is configured to slide along a yard rail segment  606  in order to facilitate in the transportation of the wind generator  300 . The yard tractor  604  will travel along the rail segment  606  to the location of the wind generator  300 . The yard tractor  604  will seize the wind generator  300  and transport the wind generator  300  to the transfer support  602 . Upon arrival at the transfer support  602 , the wind generator  300  will be secured onto the transfer support  602 . Once the wind generator  300  is secured onto the transfer support  602 , the yard tractor  604  will release its contact with the wind generator  300  and the wind generator  300  will remain on the transfer support  602 . 
     Following the positioning on the transfer support  602 , transport of the wind generator  300  from its onshore location to a water vessel  500  continues with the movement of the wind generator  300  by way of the transfer tractor  400 . 
     Step  202  within method  200  continues with the transportation of the wind generator  300  from the transfer support  602  onto the water vessel  500  In order to enable the transfer tractor  400  to travel from an onshore location to the water vessel  500 , the onshore rail system  606  and the water vessel rail segment  506  must be aligned. The use of a guide system may aid in the alignment of the onshore rail segment  606  and the water vessel rail segment  506 . In certain embodiment of the invention, a portion of the onshore rail segment  606  may be capable of lateral movement in order to facilitate alignment between the onshore rail segment  606  and the water vessel rail segment  506 . This alignment between the onshore rail segment  606  and the water vessel rail segment  506  allows for the transfer tractor  400  to travel along the rail system onto the water vessel  500 . The transfer tractor  500  may remain on the water vessel  300  in order to facilitate addition movement, as well as mounting, of the wind generator  300 . 
     In an alternative embodiment, the transfer support  602  and yard tractor  604  may not be required in order to transport the wind generator  300  from an onshore location onto the water vessel  500 . In such an embodiment, the transfer tractor  400  seizes the wind generator  300  at an onshore location. Once the transfer tractor  400  has seized the wind generator  300 , the transfer tractor  400  travels along the rail system  606  until the transfer tractor  400  has traveled onto the water vessel  500 . The transfer tractor  400  may remain on the water vessel  500  in order to further maneuver the wind generator  300  and mount the wind generator  300  onto the support structure  100 . In an embodiment of the current invention where the water vessel  500  simultaneously transports more than one wind generator  300 , a second transfer tractor  400  will retrieve a second wind generator  300  from an onshore location and transport the second wind generator  300  onto the water vessel  500 . This process is repeated from each wind generator  300  to be transported and mounted. 
     After the wind generator is loaded onto the water vessel  500 , method  200  continues with step  204 ; the water vessel travels to and aligns with the support structure. In order for the water vessel  500  to facilitate the mounting of a wind generator  300  onto the support structure  100 , the water vessel  500  must engage with the support structure  100 . As shown in  FIG. 5 , a water vessel may include one or more staging points  508 . Staging points  508  are locations where the water vessel  500  can partially surround the support structure  100 . Therefore, in the current embodiment of the present invention, the water vessel  500  will approach the support structure  100  and continues to travel until a staging point  508  partially surrounds the support structure  100 .  FIG. 7  illustrates a water vessel  500  engaged with the support structure  100 . When the water vessel  500  and the support structure  100  are engaged, as described in  FIG. 7 , the staging point  508  will partially surround the support structure  100 . In order to properly align the water vessel  500  with the support structure  100  mooring lines may be utilized. The mooring lines may act to temporarily connect the water vessel  500  with the support structure  100 . In the engaged position, the water vessel rail segment  506  located on the platform  502  will straddle the support structure  100 . 
     Once the water vessel  500  has engaged with the support structure  300 , method  200  continues when the water vessel is raised vertically, at step  206 , to a mounting height, as illustrated in  FIG. 7 . The term “mounting height” is intended to include, but is not limited to, a height which is at or above the height at which the support structure  300  extends beyond the surface of the water. The process of raising the water vessel  500  to a mounting height is accomplished through the use of the one or more retractable support legs  504  which are elements of the water vessel  500 . In order to raise the water vessel  500  vertically, the retractable support legs  504  descend vertically from their upward position until the retractable legs  504  make contact with a surface which can provide a substantial foundation to support the raised water vessel  500 . With the retractable support legs  504  firmly in contact with a surface which can provide a foundation for the raised water vessel  500 , the water vessel is hoisted to a mounting height. Methods known to one skilled in the art are employed to hoist the water vessel to a mounting height. Once the water vessel  500  is in position, the transfer tractor  400  is free to maneuver along the water vessel rail segments  506  and position itself above the staging area  508  and the support structure  100 . 
     With the water vessel  500  raised vertically, at step  206 , to a mounting height, method  200  continues when the wind generator is then mounted onto the support structure at step  208 . With the water vessel  500  in positioned at or above the height of the support structure  100 , the staging point  508  will be partially above the support structure  100 , as illustrated in  FIG. 8 . Positioning the staging point  508 , so that it is partially above the support structure  100 , allows the transfer tractor  400  to travel along the water vessel rail segment  506  and position the wind generator  300  above the support structure  100 . Positioning the wind generator  300  above the support structure  100  allows for the wind generator  300  to be easily mounted onto the support structure  100 . Once the wind generator  300  is positioned above the support structure  100 , there are multiple ways in which the wind generator  300  can be mounted onto the support structure  100 . 
     In one embodiment of the current invention, the transfer tractor  400  lowers the mast of the wind generator  300  into the crown  106  of the support structure  100 . Lowering of the wind generator  300  may be accomplished by lowering the transfer tractor platform  402  through use of the one or more hydraulic cylinders  422 , or other methods of vertically maneuvering the transfer tractor platform  402 . As the transfer tractor  400  lowers the mast of the wind generator  300  into the crown  106  of the support structure  100 , a friction connection between the inside of the crown  106  and the outside of the wind generator mast  302  is created. Further lowering of the wind generator  300  by the transfer tractor  400  allows for this friction connection to build until the friction connection is strong enough to provide a sufficient foundation to ensure that the wind generator  300  will remain stable atop the support structure  100 . In some instances where a friction connection is not used, or where a friction connection alone will not support the wind generator  300 , other known securing methods may be used. 
     An alternative method of mounting the wind generator  300  onto the support structure  100  is to lower the entire water vessel  500 . As is the case when the wind generator  300  is lowered by the transfer tractor  400 , this embodiment begins with the transfer tractor  400  positioning the wind generator  300  above the support structure  100 . However, in this embodiment, the entire water vessel  500  will be lowered thereby forcing the mast  302  of the wind generator  500  into the crown  106  of the support structure  100 . Utilizing the same machinery which hoisted the water vessel  500  to a mounting height, the water vessel  500  is lowered along the retractable support legs  504  until the friction connection between the mast  302  of the wind generator  300  and the crown  306  of the support structure  300  provide a stable foundation for the wind generator  300  to remain firmly atop the support structure  100 . In some instances where a friction connection is not used, or where a friction connection alone will not support the wind generator  300 , other known securing methods may be used. 
     The wind generator  300  could also be lowered through a combination of lowering the water vessel  500  as well as vertically maneuvering the transfer tractor platform  402 . 
     Once the wind generator  300  is mounted on the support structure  108 , method  200  is completed when the water vessel  500  returns to the floating position, at step  210 . This begins with the transfer tractor  400  releasing its contact with the mast  302  of the wind generator  300 . After the transfer tractor  400  releases contact with the mast  302  of the wind generator  300 , the transfer tractor  400  travels along the water vessel rail segment  506  away from the support structure  100 . Moving the transfer tractor  400  away from the support structure  100  will allow for the water vessel  500  to lower itself to a floating position without coming in contact with the support structure  100 . The term “floating position” is intended to include, but is not limited to, the naturally buoyant position of an object on the surface of a body of water. 
     With the transfer tractor  400  free from obstructing the lowering of the water vessel  500 , the current method  200  beings the step of returning the water vessel to the floating position, as in step  210 . The water vessel  500  is first lowered to the surface of the water. Once the water vessel has returned to the surface of the water, the retractable legs  504  are raised from below the water and returned to their upward position. Raising the retractable legs  504  eliminates the foundation support provided by the retractable legs and returns the water vessel  500  to a floating position. In embodiments of the current invention where the water vessel  500  is carrying more than one wind generator  300 , the water vessel  500  may travel to another support structure  300  and repeat the process of mounting a wind generator onto the support structure  300 . 
     Although the present invention has been described in considerable detail with reference to certain embodiments, other embodiments are possible. Therefore, the scope of the present invention is not limited to the description of the versions and embodiments expressly disclosed herein. The references and disclosure provided in the ‘Background of the Invention’ section are not admitted to be prior art with respect to the disclosure provided in the present application.