Plant, generator and propeller element for generating energy from water currents

Abstract

A plant, generator and rotating member for the production of power from currents in a body of water, comprising a fixedly mounted of floating structure, and a plurality of replaceable generator units ( 750 ) supported by the structure and which are driven by the water currents. The structure comprises arms ( 615, 720, 730 ). The rotating member ( 400 ) comprises a plurality of member sections ( 410 ) rotatably mounted on a shaft ( 405 ) between an end piece ( 407 ) and a tip ( 406 ). The generator comprises a contra-rotating rotor ( 550 ) and stator ( 800 ) connected to respective shafts ( 500, 820 ) and bearings, where the stator frame ( 800 ) is axially supported ( 810 ) on the first shaft ( 500 ) and the first shaft ( 500 ) at one end thereof is axially supported ( 810 ) on the stator frame. The generator according to the invention can be used for the production of electric power, and as an electromotor for the production of mechanical rotational energy.

1 - 29 . (canceled) 
     
     
         30 . A plant for the production of energy from currents in a body of water, comprising a structure capable of resting on a bottom (B) below said body of water, and a plurality of replaceable generator units ( 750 ) supported by the structure and adapted to be driven by the water currents, wherein said plant is characterised in that the structure comprises at least three interconnected nodal elements ( 700 ) having a respective nodal centre and substantially horizontal arms ( 720 ,  730 ) projecting therefrom, and that each nodal centre is made in the form of a bushing ( 711 ,  712 ) for a height-adjustable support leg ( 760 ) extending towards the bottom (B). 
     
     
         31 . A plant according to  claim 30 , characterised in that the nodal elements ( 700 ) are interconnected by means of connecting members ( 740 ) between selected ones of the said arms. 
     
     
         32 . A plant according to  claim 30 , characterised in that the generator units ( 750 ) are supported by elongate supports ( 749 ) extending from the arms and/or from any connecting members down into the body of water. 
     
     
         33 . A plant according to  claim 32 , characterised in that the arms, supporting legs, the optional connecting members and the elongate supports are tubular members. 
     
     
         34 . A plant according to  claim 30 , characterised in that the supporting legs have one or more ballastable chambers. 
     
     
         35 . A plant according to  claim 32 , characterised in that a generator unit is pivotally supported about a vertical axis at the free end of the respective elongate support. 
     
     
         36 . Plant according to  claim 32 , characterised in that a generator unit is fixedly mounted at the free end of the respective elongate support. 
     
     
         37 . A plant according to  claim 30 , characterised in that a supporting leg ( 760 ) is arranged in a respective corner of an imaginary equilateral triangle. 
     
     
         38 . A plant according to  claim 30 , characterised in that it is mobile when the supporting legs ( 760 ) are deballasted. 
     
     
         39 . A plant according to  claim 30 , characterised in that it is stationary and does not require anchoring to the bottom (B) when the supporting legs ( 760 ) are ballasted. 
     
     
         40 . A plant according to  claim 32 , characterised in that supporting and connecting members ( 720 ,  730 ,  740 ,  749 ) are buoyancy members so as to provide the plant with positive buoyancy when the supporting legs are deballasted. 
     
     
         41 . A plant according to  claim 30 , characterised in that each generator unit shaft is equipped with at least one rotating member ( 400 ). 
     
     
         42 . A plant according to  claim 30 , characterised in that the plant comprises at least three nodal units, and hence at least three supporting legs, and that the plant is thus statically determinant when it is ballasted against said bottom (B). 
     
     
         43 . A plant according to  claim 30 , characterised in that the generator units are so arranged that the individual rotational planes formed on rotation of the rotating members ( 400 ) essentially overlap each other in such manner that a minimum amount of water can flow round the generators. 
     
     
         44 . A plant according to  claim 30 , characterised in that each generator unit is equipped with at least one rotating member ( 400 ) rotationally mounted on each side of said generator housing. 
     
     
         45 . A plant according to  claim 41 , characterised in that the rotating members are contra-rotating. 
     
     
         46 . A plant according to  claim 44 , characterised in that the rotating members are contra-rotating. 
     
     
         47 . A plant for the production of energy from currents in a body of water, comprising a structure capable of resting on the bottom (B) below said body of water, and a plurality of replaceable generator units ( 750 ) supported by the structure and adapted to be driven by the water currents, characterised in that said plant can be positioned on the bottom (B) below a body of water with the aid of at least three supporting legs ( 760 ) which are movable through respective bushings ( 711 ,  712 ), and that the plant can selectively, by means of the supporting legs, be brought into a chosen height in the body of water in order to optimise the position of the generators in the body of water, or above the surface (S) of the body of water so that said generator units ( 750 ) are above the surface of the water.