Tidal Flow Power Generation

Abstract

A structure for a tidal flow energy generation system is fabricated from tubular framework having tubular modules with mounts for respective tidal flow turbine nacelles. The node modules include tubular limbs extending in transverse directions and elongate tubes and provided to interconnect with the tube limbs of the node modules. The structure can be pre-fabricated and transported to a location for deployment. The structure can be deployed by means of hovering the assembled structure to the seabed, for example by means of flooding the structure.

1 . A structure for use in a tidal flow energy generation system, the structure comprising a tubular framework comprising:
 a plurality of tubular node modules having mounting means for mounting a respective tidal flow turbine nacelle, the respective node modules including tubular limbs extending in transverse directions; and   elongate tubes extending to interconnect with the tube limbs of the node modules.   
     
     
         2 . A structure according to  claim 1 , wherein:
 the tubular limbs of a respective node module extend at an acute angle relative to one another.   
     
     
         3 . A structure according to  claim 1 , wherein:
 the structure is triangular in footprint having three node modules, each positioned at a respective vertex of the triangular footprint.   
     
     
         4 . A structure according to  claim 1 , wherein:
 a respective node module is open to inflow of water through both ends of at least one of the tube limbs.   
     
     
         5 . A structure according to  claim 1 , wherein:
 a respective node module is provided with a valve or baffle arrangement which in an open configuration permits fluid passage via the end of at least one of the tube limbs.   
     
     
         6 . A structure according to  claim 1 , wherein:
 the node modules carry respective ground engaging support elements.   
     
     
         7 . A structure according to  claim 6 , wherein:
 the ground engaging support elements comprise self levelling devices for levelling the structure.   
     
     
         8 . A structure according to  claim 1 , wherein:
 the mounting means for mounting a respective tidal flow turbine nacelle with a respective node module comprises a receiving bore for receiving the shaft of a respective nacelle.   
     
     
         9 . A structure according to  claim 1 , wherein:
 the node modules carry respective ground engaging support elements, the mounting means for mounting a respective tidal flow turbine nacelle with a respective node module comprises a receiving bore for receiving the shaft of a respective nacelle, the receiving bore extending into the respective ground engaging support element.   
     
     
         10 . A structure according to  claim 1 , further comprising:
 a lifting line arrangement connected to the structure and remaining connected following deployment of the structure on the seabed.   
     
     
         11 . A structure according to  claim 10 , wherein:
 the lifting line arrangement is connected at a plurality of the node modules.   
     
     
         12 . A structure according to  claim 10 , wherein:
 the lifting line arrangement comprises a lifting bridle comprising a plurality of lifting line elements, and a lifting connection for connection to the hook of a crane; the bridle being connected to a locating line which extends away from the location of the structure to a fixed position.   
     
     
         13 . A method of deploying a structure for use in a tidal flow energy generation system, the method comprising:
 pre-fabricating the structure including a plurality of node modules having mounting means for mounting a respective tidal flow turbine nacelle, the respective node modules including limbs extending in transverse directions and, elongate structural elements extending to interconnect with the limbs of the node modules;   transporting the prefabricated structure to a location for deployment; and   deploying the structure by means of lowering the assembled structure to the seabed.   
     
     
         14 . A method according to  claim 13 , wherein:
 the node modules have tubular limbs and the elongate interconnecting elements comprise tubular elements connecting with the tubular limbs, the deployment of the structure including flooding substantially the entire interior of the tubular framework of the structure.   
     
     
         15 . A method according to  claim 13 , wherein:
 a deployment/lifting line arrangement is connected to the structure and remains connected following deployment of the structure on the seabed to be available for use in subsequently lifting the structure.   
     
     
         16 . A method according to  claim 15 , wherein:
 the lifting line arrangement comprises a lifting bridle comprising a plurality of lifting line elements, and a lifting connection for connection to the hook of a crane; the bridle being connected to a locating line which, following deployment of the structure on the seabed, extends away from the location of the structure to a fixed position.   
     
     
         17 . A method according to  claim 13 , wherein:
 the structure is deployed from the surface to the seabed with a respective turbine nacelle arrangement already received in position in a receiving structure of a respective node module.   
     
     
         18 . A method according to  claim 17 , wherein:
 an electrical cable connection to the respective turbine nacelle is made prior to deployment from the surface to the seabed.   
     
     
         19 . A structure for us in a tidal flow energy generation system, comprising:
 a tubular framework including a plurality of tubular node modules and elongate tubes interconnecting said plurality of tubular node modules, each tubular node module including a receiving bore which receives a shaft of a respective tidal flow turbine nacelle and at least two tubular limbs extending in transverse directions, and at least one node module being open to inflow of water through at least one of the tubular limbs; and   a lifting bridle connected to the tubular framework.   
     
     
         20 . A structure according to  claim 19 , wherein:
 the structure is triangular in footprint having three said tubular node modules, each positioned at a respective vertex of the triangular footprint;   at least one of said three tubular node modules is provided with a valve or baffle arrangement which in an open configuration permits fluid passage via the end of at least one of the tube limbs; and   said tubular node modules carry respective ground engaging support elements for levelling the structure.