Ocean Thermal Energy Conversion Power Plant

Abstract

An offshore power generation structure comprising a submerged portion having a first deck portion comprising an integral multi-stage evaporator system, a second deck portion comprising an integral multi-stage condensing system, a third deck portion housing power generation equipment, cold water pipe; and a cold water pipe connection.

1 - 25 . (canceled) 
     
     
         26 . A method of connecting submerged vertical pipe to a floating structure comprising:
 connecting lifting and retention cables to an upper portion of a cold water pipe, wherein the cold water pipe upper portion comprises a lifting collar having a tapered connecting surface;   drawing the cold water pipe into a spar receiving bay using the lifting and retention cables, wherein the receiving bay comprises a tapered surface for receiving the cold water pipe upper portion and a contact pad;   causing the tapered connecting surface of cold water pipe to make a sealable contact with the contact pad of the receiving bay; and   mechanically fixing the lifting cables to maintain the sealable contact between the connecting surface and the contact pad.   
     
     
         27 . A submerged pipe connection assembly comprising:
 a connection structure comprising a lower portion having lifting devices, lifting cables, a first tapered connecting surface and a contact pad; and   a vertical pipe comprising:
 a first longitudinal portion comprising a lifting collar having a second tapered connecting surface and lifting eyes; 
 a second longitudinal portion below the first portion, wherein the second portion is more flexible than the first portion. 
   
     
     
         28 . The submerged pipe connection assembly of  claim 27  further comprising:
 a third longitudinal portion below the second longitudinal portion and wherein the third portion is less flexible than the second portion. 
 
     
     
         29 . The submerged pipe connection assembly of  claim 27  wherein the second tapered connecting surface is in contact with the contact pad of the first tapered connecting surface so as to form a watertight seal. 
     
     
         30 . The submerged pipe connection assembly of  claim 27  wherein the assembly is part of an OTEC system. 
     
     
         31 . A submerged vertical pipe connection comprising:
 a floating structure having a vertical pipe receiving bay, wherein the receiving bay has a first diameter;   a vertical pipe for insertion into the pipe receiving bay, the vertical pipe having a second diameter smaller than the first diameter of the pipe receiving bay;   a bearing surface; and   one or more detents operable with the bearing surface, wherein the detents define a diameter that is different than the first or second diameter when in contact with the bearing surface.   
     
     
         32 . A method of connecting a submerged vertical pipe to a floating platform comprising:
 providing a floating structure having a vertical pipe receiving bay, wherein the pipe receiving bay has a first diameter;   providing a vertical pipe having a top end portion that has a second diameter that is less than the first diameter;   inserting the top end portion of the vertical pipe into the receiving bay;   providing a bearing surface for supporting the vertical pipe;   extending one or more detents such that the one or more detents have a diameter that is different from the first or second diameters; and   contacting the one or more detents with the bearing surface to suspend the vertical pipe from the floating structure.   
     
     
         33 - 35 . (canceled) 
     
     
         36 . The submerged pipe connection assembly of  claim 27 , comprising a virtual hinge tapered from a first diameter adjacent the engagement portion to a smaller second diameter adjacent the fixed interface. 
     
     
         37 . The submerged pipe connection assembly of  claim 36 , wherein the engagement portion of the interface section is tapered from a first diameter adjacent the virtual hinge to a smaller second diameter at the end of the interface section in contact with the vessel. 
     
     
         38 . The submerged pipe connection assembly of  claim 36 , wherein the virtual hinge is configured to provide up to 2 degrees of deflection. 
     
     
         39 . The submerged pipe connection assembly of  claim 27 , wherein the engagement portion includes mating plates with insertion holes sized to receive engaging members on the vessel. 
     
     
         40 . The submerged pipe connection assembly of  claim 39 , wherein the mating plates are arranged around the outer surface of the spar interface section. 
     
     
         41 . The submerged pipe connection assembly of  claim 40 , wherein the vessel comprises receiving plates aligned with mating plates. 
     
     
         42 . The submerged pipe connection assembly of  claim 39 , wherein the engaging members comprise ball locks within in the vessel, the ball locks inserted into the insertion holes in the mating plates to secure the cold water pipe in position for operation. 
     
     
         43 . The submerged pipe connection assembly of  claim 42 , wherein a top edge of the interface section has a stainless steel mating ring. 
     
     
         44 . The submerged pipe connection assembly of  claim 43 , wherein mating plates are arranged around the inner and outer surfaces of the interface section and are secured (e.g., welded) to the mating ring. 
     
     
         45 . The submerged pipe connection assembly of  claim 44 , wherein the face plates around the inner surface of the interface section are connected to the face plates arranged along the outer surface. 
     
     
         46 . The submerged pipe connection assembly of  claim 44 , wherein the interface section comprises multiple tension beams extending along more than half of the entire vertical distance of the interface section to provide tensile strength while allowing slight angular flexure. 
     
     
         47 . The submerged pipe connection assembly of  claim 46 , wherein the tension beams are positioned approximately between the inner and outer surfaces of the interface section and are bolted between the inner and outer face plates. 
     
     
         48 . The submerged pipe connection assembly of  claim 46 , wherein the fixed interface also comprises face plates are arranged around the inner and outer surfaces of the fixed interface and fastened together and a lower end of the tension beams. 
     
     
         49 . The submerged pipe connection assembly of  claim 48 , wherein the fixed interface includes recessed portions between the tension beams and the inner and outer face plates to receive corresponding tab features of the middle section of the cold water pipe.