Apparatus, System and Method For Generating Power In A Wellbore

Abstract

An apparatus, system and method provides electrical power in a subterranean well. A radioisotope thermoelectric generator may be positioned and installed in a downhole location in a wellbore. The location of the radioisotope thermoelectric generator may be within a completion string. A radioisotope thermoelectric generator comprises a core having a radioisotope for producing heat, and a thermocouple. The thermocouple comprises at least two different metals, and is positioned adjacent to the core. The radioisotope thermoelectric generator flows heat from the core to the thermocouple to produce electricity that may be stored in an energy storage device, or used to power a component. The produced electrical power may be employed to activate downhole sensors, valves, or wireless transmitters associated with the operation and production of an oil or gas well.

What is claimed is: 
     
         1 . A system for providing electrical power in a subterranean well, the system comprising:
 (a) a radioisotope thermoelectric generator positioned and installed in a downhole location;   (b) the radioisotope thermoelectric generator comprising:
 (i) a core having a radioisotope for producing heat, and 
 (ii) a thermocouple positioned adjacent to the core, 
   (c) the radioisotope thermoelectric generator being configured for flowing heat from the core to the thermocouple to produce electricity;   (d) a production packer installed in a downhole location, wherein the radioisotope thermoelectric generator is positioned below the production packer;   (e) an interval control valve positioned below the production packer;   (f) a conductive cable connected to the thermocouple configured to transmit electricity along the conductive cable to the electric interval control valve, and   (g) wherein cabled transmission of electrical power across a packer is not required in the system.   
     
     
         2 . The system of  claim 1 , wherein the conductive cable is located in the annulus between a production string and a production tubing thereby connecting the electric interval control valve with the radioisotope thermoelectric generator. 
     
     
         3 . The system of  claim 1 , wherein the radioisotope is selected from one or more of the following radioisotopes: plutonium, uranium, curium, strontium, polonium, promethium, caesium, cerium, ruthenium, cobalt, thulium, and americium. 
     
     
         4 . The system of  claim 1 , further comprising a sensor positioned below the production packer and configured to be powered by the radioisotope thermoelectric generator. 
     
     
         5 . The system of  claim 1 , further comprising a wireless transmitter positioned below the production packer and configured to be powered by the radioisotope thermoelectric generator. 
     
     
         6 . The system of  claim 5 , wherein the wireless transmitter is configured to produce acoustic signals. 
     
     
         7 . The system of  claim 5 , wherein the wireless transmitter is configured to produce electromagnetic signals for propagation upwards within the well. 
     
     
         8 . The system of  claim 1 , further comprising an electric storage device positioned below the production packer. 
     
     
         9 . A system for providing electrical power in a wellbore, the wellbore having installed therein a completion string with production tubing, the production tubing being configured for transportation of hydrocarbons from a subterranean formation upwards and through the completion string, the system comprising:
 (a) a radioisotope thermoelectric generator positioned and installed below the production string and within the completion string,   (b) the radioisotope thermoelectric generator comprising:
 (i) a core having a radioisotope for producing heat, the radioisotope being selected from one or more of the following: plutonium, and americium, and 
 (ii) a thermocouple positioned adjacent to the core, 
   (c) the radioisotope thermoelectric generator being configured for flowing heat from the core through the thermocouple to produce electricity,   (d) a production packer installed in a downhole location, wherein the radioisotope thermoelectric generator is positioned below the production packer;   (e) an interval control valve positioned below the production packer;   (f) a conductive cable connected to the thermocouple configured to transmit electricity along the conductive cable to the electric interval control valve, wherein the conductive cable is located in the annulus between the production string and the production tubing thereby connecting the electric interval control valve with the radioisotope thermoelectric generator; and   (g) wherein cabled transmission of electrical power across a packer is not required in the system.   
     
     
         10 . A method of generating power and controlling flow in a subterranean formation in a well below a production packer, the method comprising:
 (a) providing a radioisotope thermoelectric generator positioned and installed within a completion string and below a production packer in a subterranean well, the radioisotope thermoelectric generator comprising a core having a radioisotope for producing heat and a thermocouple positioned adjacent to the core;   (b) generating heat in the core by radioactive decay of the radioisotope;   (c) flowing heat from the core to the thermocouple;   (d) producing electricity;   (e) providing a production packer in the subterranean well, the radioisotope thermoelectric generator being positioned below the production packer;   (f) providing a production tubing below the production packer in the subterranean well;   (g) providing at least one electric interval control valve in the subterranean well, the electric interval control valve being positioned below the production packer, the electric interval control valve being adapted for regulating reservoir flow to the production tubing of the subterranean well;   (h) transmitting the electricity along a conductive cable, which is located between the production tubing and a production string to the interval control valve;   (i) employing the electricity to additionally activate a sensor,   (j) determining the characteristics of fluid production into a well using the sensor; and   (k) wherein cabled transmission of electrical power across a packer is not required in the system.   
     
     
         11 . The method of  claim 10 , wherein the sensor measures and reports temperature characteristics. 
     
     
         12 . The method of  claim 10 , wherein the sensor measures and reports pressure characteristics. 
     
     
         13 . The method of  claim 10 , wherein the sensor measures and reports water content of production fluids. 
     
     
         14 . The method of  claim 10 , wherein the sensor measures and reports oil content of production fluids. 
     
     
         15 . The method of  claim 10 , wherein the sensor measures and reports gas content of production fluids. 
     
     
         16 . The method of  claim 10 , wherein the sensor measures and reports ratio of water produced to the total volume of liquids produced in a subterranean zone within the well. 
     
     
         17 . The method of  claim 10 , further comprising providing at least one wireless transmitter powered by the radioisotope thermoelectric generator. 
     
     
         18 . The method of  claim 17 , wherein the wireless transmitter is an acoustic wireless transmitter. 
     
     
         19 . The method of  claim 10 , further comprising providing at least one wireless receiver powered by the radioisotope thermoelectric generator. 
     
     
         20 . The method of  claim 19 , wherein the wireless receiver is an acoustic wireless receiver.