Floatable transportation and installation structure for transportation and installation of a floating wind turbine, a floating wind turbine and method for transportation and installation of the same

A floating wind turbine, comprising counter securing means connectable to securing means of a floatable transportation and installation structure for transportation and installation of the floating wind turbine, wherein the floatable transportation and installation structure has a floating depth and the floating wind turbine has a floating depth, wherein floating depth is defined as the distance between the surface of a body of water and the bottom of a floating structure, and wherein said transportation and installation structure comprises:

• securing means for detachably and temporarily securing the floatable transportation and installation structure to the floating wind turbine in such a way that the floating wind turbine is stabilized and can be moved by moving the transportation and installation structure,
• an accommodation area where the floating wind turbine can be accommodated in such a way that the floatable transportation and installation structure is at least partially enclosing the floating wind turbine,
• at least one opening-closing structure or similar gate structure for reversibly fully enclosing the accommodation area around the secured floating wind turbine, and
• ballastable and de-ballastable floating means comprising a plurality of hollow vertical members in fluidic communication with a plurality of tubular cross members, wherein the ballastable and de-ballastable floating means is configured in such a way that the floating depth of the floatable transportation and installation structure is changed by ballasting and de-ballasting the floating means respectively, and by taking water and/or ejecting water respectively, in a situation where the floatable transportation and installation structure is secured to the floating wind turbine and/or in a situation where the floatable transportation and installation structure is separated from the floating wind turbine, wherein in a situation where the floatable transportation and installation structure is secured to the floating wind turbine, the change in the floating depth of the wind turbine is equal to the change in the floating depth of the floatable transportation and installation structure.

A method for transportation and installation of an almost fully assembled and erected floating wind turbine, wherein the floating wind turbine has a floating depth, wherein floating depth is defined as the distance between the surface of a body of water and the bottom of a floating structure, the method comprising:

• securing the essentially fully assembled and erected floating wind turbine to a floatable transportation and installation structure at an accommodation area of the floatable transportation and installation structure, wherein the floatable transportation and installation structure has ballasting and de-ballasting means comprising a plurality of hollow vertical members in fluidic communication with a plurality of tubular cross members, wherein the essentially fully assembled and erected floating wind turbine is secured to the floatable transportation and installation structure in such a way that the erected floating wind turbine is stabilized and can be moved by moving the transportation and installation structure and wherein the floating wind turbine is accommodated at the accommodation area in such a way that the floatable transportation and installation structure is at least partially enclosing the floating wind turbine wherein the accommodation area around the floating wind turbine is reversibly essentially fully enclosed by at least one opening-closing structure or similar gate structure, and wherein the transportation and installation structure has a floating depth;
• moving the floating wind turbine to a designated position by moving the floatable transportation and installation structure to said designated position;
• securing the floating wind turbine to fixations means provided at the given position;
• detaching the transportation and installation structure from the now fixed floating wind turbine and separating the floatable transportation and installation structure from the wind turbine, wherein the opening-closing structure or similar gate structure, which is essentially fully enclosing the accommodation area, is opened;
• ballasting the floatable transportation and installation structure in such a way that the attached floating wind turbine is lowered further into the water, wherein the change in the floating depth of the wind turbine is equal to the change in the floating depth of the floatable transportation and installation structure;
• securing the lowered floating wind turbine to fixations means;
• separating the lowered floatable transportation and installation structure from the fixed floating wind turbine;
• and
• de-ballasting the floatable transportation and installation structure in such a way that the floatable transportation and installation structure is lifted in the water.