In-riser power generation

Abstract

In-riser power generation devices and methods are utilized to generate power subsea to operate subsea devices of a subsea well system. A turbine power generator is located in fluid communication with a subsea fluid flow path of a subsea well system and the turbine power generator is operationally connected to a subsea power device.

What is claimed is: 
     
         1 . A subsea well system, comprising:
 a subsea fluid flow path;   a riser extending from a vessel located at a water surface to a blowout preventer stack located at a seafloor;   a subsea tree landed in the blowout preventer on a landing string comprising a bore;   the landing string extending in the riser from the vessel forming an annulus between the landing string and the riser; and   a turbine power generator in fluid communication with the subsea fluid flow path.   
     
     
         2 . The system of  claim 1 , wherein the subsea fluid flow path is the bore. 
     
     
         3 . The system of  claim 1 , wherein the subsea fluid flow path is the annulus. 
     
     
         4 . The system of  claim 1 , wherein the subsea fluid flow path is a transverse pathway formed through the landing string between the bore and the annulus. 
     
     
         5 . The system of  claim 1 , wherein the subsea fluid flow path is a hydraulic conduit connecting a subsea hydraulic power device and a subsea hydraulically actuated device. 
     
     
         6 . The system of  claim 1 , wherein the subsea fluid flow path comprises:
 a sealed annular region in the blowout preventer stack;   a blowout preventer kill line in fluid communication with the sealed annular region; and   a blowout preventer choke line in fluid communication with the sealed annular region.   
     
     
         7 . The system of  claim 1 , further comprising:
 a packer providing a seal between the landing string and the riser; and   a pathway formed through the packer providing fluid communication in the annulus across the packer, wherein the turbine power generator is located in the pathway.   
     
     
         8 . The system of  claim 1 , wherein the subsea fluid flow path comprises:
 a sealed annular region formed in the blowout preventer stack between a first closed ram and a second closed ram;   a conduit providing fluid communication between the sealed annular region and the annulus; and   a blowout preventer access line in fluid communication with the sealed annular region.   
     
     
         9 . A method of generating power in a subsea well system, comprising:
 directing fluid flow across a turbine power generator located in fluid communication with a subsea fluid flow path of a subsea well system, the subsea well system including a riser extending from a vessel located at a water surface to a blowout preventer stack located at a seafloor, a subsea tree landed in a passage of the blowout preventer stack on a landing string comprising a bore, the landing string extending in the riser from the vessel forming an annulus between the landing string and the riser; and   generating power in response to the fluid flow across the turbine power generator.   
     
     
         10 . The method of  claim 9 , wherein the directing the fluid flow comprises:
 sealing an annular region in the blowout preventer stack; and   circulating the fluid flow from the vessel into the sealed annular region, wherein the subsea fluid flow path comprises a conduit extending from an inlet located in the annular region to the annulus.   
     
     
         11 . The method of  claim 9 , wherein the directing the fluid flow comprises:
 sealing an annular region of the blowout preventer stack; and   circulating the fluid flow from a first blowout preventer access line into the sealed annular region and from the sealed annular region into a second blowout preventer access line.   
     
     
         12 . The method of  claim 9 , wherein the turbine power generator is located in one of the first blowout access line and the second blowout preventer access line. 
     
     
         13 . The method of  claim 9 , wherein the subsea fluid flow path is the bore of the landing string. 
     
     
         14 . The method of  claim 9 , wherein the subsea fluid flow path is the annulus. 
     
     
         15 . The method of  claim 9 , wherein the subsea fluid flow path is a transverse pathway formed through the landing string. 
     
     
         16 . The method of  claim 9 , wherein:
 the subsea fluid flow path comprises a transverse path formed through the landing string; and   the directing the fluid flow comprises circulating fluid from one of the bore and the annulus through the transverse pathway to the other of the bore and the annulus.   
     
     
         17 . An in-riser power generation device, the device comprising:
 a sub member for connecting in a landing string to form a bore between a vessel located at a surface of a water and a blowout preventer stack located at a seafloor;   a pathway formed through the sub member to communicate fluid flow when the sub member is connected in the landing string; and   a turbine power generator positioned in the pathway.   
     
     
         18 . The device of  claim 17 , wherein the pathway is a transverse pathway extending from the bore to an exterior of the sub member. 
     
     
         19 . The device of  claim 18 , further comprising a valve member moveably positioned to open and close the pathway. 
     
     
         20 . The device of  claim 17 , wherein the sub member is a packer element adapted to seal between the landing string and a riser in which the landing string is disposed.