SORFC power and oxygen generation method and system

• US 20040191598A1
• Filed: 03/24/2003
• Published: 09/30/2004
• Est. Priority Date: 03/24/2003
• Status: Active Grant

• Current Assignee: Bloom Energy Corporation
• Original Assignee: Bloom Energy Corporation
• Inventors: Gottmann, Matthias, Sridhar, K.R., Mitlitsky, Fred, McElroy, James Frederick
• Granted Patent: US 7,045,238 B2
• Time in Patent Office: Days
• US Class Current: 429/418
• CPC Class Codes: C25B 1/00 Electrolytic production of inorganic compounds or non-metals
• CPC Class Codes: C25B 1/04 by electrolysis of water
• CPC Class Codes: C25B 9/73 of the filter-press type
• CPC Class Codes: H01M 8/04014 Heat exchange using gaseous fluids; Heat exchange by combustion of reactants
• CPC Class Codes: H01M 8/04119 with simultaneous supply or evacuation of electrolyte; Humidifying or dehumidifying
• CPC Class Codes: H01M 8/04231 Purging of the reactants
• CPC Class Codes: H01M 8/0625 in a modular combined reactor/fuel cell structure
• CPC Class Codes: H01M 8/0656 by electrochemical means H01M8/065 takes precedence
• CPC Class Codes: H01M 8/1231 with both reactants being gaseous or vaporised
• CPC Class Codes: H01M 8/186 by electrolytic decomposition of the electrolytic solution or the formed water product
• CPC Class Codes: Y02E 60/36 Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 20/129 Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines
• CPC Class Codes: Y02P 20/133 Renewable energy sources, e.g. sunlight

Abstract

A solid oxide regenerative fuel cell system is used to supply power in a fuel cell mode and to generate metabolic oxygen and a hydrocarbon fuel reserve in an electrolysis mode. The system may also be used as a secondary power source or for energy peak shaving applications.

Claims

1. A terrestrial power generation system, comprising:

a solid oxide regenerative fuel cell;

a hydrocarbon fuel source connected to the solid oxide regenerative fuel cell fuel inlet, wherein the solid oxide regenerative fuel cell is adapted to generate and provide a hydrocarbon fuel to the hydrocarbon fuel source in an electrolysis mode; and

an oxygen source connected to the solid oxide regenerative fuel cell oxidizer inlet.

2. The system of claim 1, wherein:

the solid oxide regenerative fuel cell is adapted to generate power in a fuel cell mode from stored oxygen supplied from the oxygen source and from fuel supplied from the hydrocarbon fuel source; and

the solid oxide regenerative fuel cell is adapted to generate metabolic oxygen for a life support system in the electrolysis mode when power is provided to the solid oxide regenerative fuel cell.

3. The system of claim 2, wherein the system is located in an underwater vehicle.

4. The system of claim 2, wherein the system is located in a high altitude aircraft or terrestrial orbit space craft that is adapted to operate in rarefied air or an airless environment.

5. The system of claim 2, wherein the system is located in an underground or underwater location that lacks access to atmospheric air.

6. The system of claim 2, wherein:

the hydrocarbon fuel source comprises a methane storage vessel which is adapted to store methane generated by the solid oxide fuel cell in the electrolysis mode and which is adapted to supply methane to the solid oxide fuel cell in the fuel cell mode;

the oxygen source comprises an oxygen storage vessel; and

the solid oxide regenerative fuel cell is adapted to generate power in a fuel cell mode by converting oxygen and methane into carbon dioxide and water vapor;

the solid oxide regenerative fuel cell is adapted to generate the metabolic oxygen for the life support system and methane fuel in the electrolysis mode when power, water vapor and carbon dioxide are provided to the solid oxide regenerative fuel cell; and

the solid oxide regenerative fuel cell is adapted to generate heat in the fuel cell mode and in the electrolysis mode.

7. The system of claim 6, further comprising:

a plurality of solid oxide regenerative fuel cell stacks; and

a carbon dioxide storage vessel connected to the solid oxide regenerative fuel cell.

8. The system of claim 7, further comprising:

an enthalpy recovery unit adapted to recover enthalpy and water vapor from fuel exhaust and to provide the recovered enthalpy and water vapor into the fuel inlet stream in the fuel cell mode;

a hydrogen recovery unit adapted to recover hydrogen from the fuel exhaust and to provide the recovered hydrogen into the fuel inlet stream in the fuel cell and electrolysis modes; and

a Sabatier reactor adapted to convert hydrogen and carbon monoxide emitted from the solid oxide regenerative fuel cell to methane and water vapor and to transfer heat from an outlet stream to the inlet stream in the electrolysis mode.

9. The system of claim 1, further comprising a renewable energy source.

10. The system of claim 9, wherein:

the renewable energy source comprises a solar cell or a wind turbine electrically connected to the solid oxide regenerative fuel cell;

the solid oxide regenerative fuel cell is adapted to generate power in a fuel cell mode when the renewable energy source is not generating power; and

the solid oxide regenerative fuel cell is adapted to generate oxygen and fuel in electrolysis mode when power is provided to the solid oxide regenerative fuel cell from the renewable energy source.

11. An underwater vehicle, comprising:

an underwater vehicle body; and

a solid oxide regenerative fuel cell.

12. The underwater vehicle of claim 11, further comprising a primary power generator.

13. The underwater vehicle of claim 12, wherein:

the solid oxide regenerative fuel cell is adapted to generate power in a fuel cell mode when the primary power generator is off; and

the solid oxide regenerative fuel cell is adapted to generate metabolic oxygen for an underwater vehicle crew life support system in an electrolysis mode when the primary power generator provides power to the solid oxide regenerative fuel cell.

14. The underwater vehicle of claim 11, further comprising:

a plurality of solid oxide regenerative fuel cell stacks;

a hydrocarbon fuel source connected to the solid oxide regenerative fuel cell stack fuel inlet; and

an oxygen source connected to the solid oxide regenerative fuel cell stack oxidizer inlet.

15. The underwater vehicle of claim 11, wherein:

the hydrocarbon fuel source comprises a methane storage vessel;

the oxygen source comprises a liquid oxygen storage vessel; and

the solid oxide regenerative fuel cell is adapted to generate power in a fuel cell mode by converting oxygen and methane into carbon dioxide and water vapor;

the solid oxide regenerative fuel cell is adapted to generate oxygen for an underwater vehicle crew life support system and methane fuel in an electrolysis mode when power, water vapor and carbon dioxide are provided to the solid oxide regenerative fuel cell; and

the solid oxide regenerative fuel cell is adapted to generate heat to heat the underwater vehicle in the fuel cell mode and in the electrolysis mode.

16. The underwater vehicle of claim 15, further comprising:

an enthalpy recovery unit adapted to recover enthalpy and water vapor from fuel exhaust and to provide the recovered enthalpy and water vapor into the fuel inlet stream in the fuel cell mode;

a hydrogen recovery unit adapted to recover hydrogen from the fuel exhaust and to provide the recovered hydrogen into the fuel inlet stream in the fuel cell and electrolysis modes; and

a Sabatier reactor adapted to convert hydrogen and carbon monoxide emitted from the solid oxide regenerative fuel cell to methane and water vapor and to transfer heat from an outlet stream to the inlet stream in the electrolysis mode.

17. The underwater vehicle of claim 11, wherein the underwater vehicle lacks a battery which provides power to an underwater vehicle propulsion system.

18. The underwater vehicle of claim 11, wherein the underwater vehicle lacks a diesel engine.

19. The underwater vehicle of claim 11, wherein the underwater vehicle lacks a battery which provides power to an underwater vehicle propulsion system and the underwater vehicle lacks a diesel engine.

20. A terrestrial power and oxygen generation system, comprising:

a solid oxide regenerative fuel cell; and

a life support system adapted to provide oxygen to support life;

wherein the oxygen outlet of the solid oxide regenerative fuel cell is operably connected to the life support system to provide oxygen from the solid oxide regenerative fuel cell to the life support system when the solid oxide regenerative fuel cell is operated in an electrolysis mode.

21. The system of claim 20, further comprising:

a power distribution system connected to a power output of the solid oxide regenerative fuel cell; and

a hydrocarbon fuel source connected to a fuel inlet of the solid oxide regenerative fuel cell;

wherein;

the solid oxide regenerative fuel cell is adapted to generate power from stored oxygen supplied from an oxygen source and from hydrocarbon fuel supplied from the hydrocarbon fuel source when the solid oxide regenerative fuel cell is operated in a fuel cell mode; and

the solid oxide regenerative fuel cell is adapted to generate hydrocarbon fuel to be stored in a hydrocarbon fuel storage vessel when the solid oxide regenerative fuel cell is operated in an electrolysis mode.

22. The system of claim 21, wherein the system is located in an underwater vehicle.

23. The system of claim 21, wherein the system is located in at least one of the following locations selected from a high altitude aircraft or terrestrial orbit space craft that is adapted to operate in an airless environment and underground or underwater location that lacks access to atmospheric air.

24. The system of claim 21, wherein the system is located in a building at least a portion of which can be sealed from outside atmosphere, wherein the system is adapted to provide oxygen to the building life support system and waste heat for at least one appliance located in the building.

25. The system of claim 20, further comprising:

a plurality of solid oxide regenerative fuel cell stacks; and

a carbon dioxide storage vessel connected to the solid oxide regenerative fuel cell;

wherein;

the hydrocarbon fuel source comprises a methane storage vessel;

the oxygen source comprises a liquid oxygen storage vessel; and

the solid oxide regenerative fuel cell is adapted to generate power in a fuel cell mode by converting oxygen and methane into carbon dioxide and water vapor;

the solid oxide regenerative fuel cell is adapted to generate metabolic oxygen for a life support system and methane fuel in the electrolysis mode when power is provided to the solid oxide regenerative fuel cell; and

the solid oxide regenerative fuel cell is adapted to generate heat in the fuel cell mode and in the electrolysis mode.

26. A terrestrial solid oxide regenerative fuel cell system, comprising:

a solid oxide regenerative fuel cell; and

at least one of;

a first means for providing oxygen from the solid oxide regenerative fuel cell to a life support system when the solid oxide regenerative fuel cell is operated in an electrolysis mode; and

a second means for providing hydrocarbon fuel to be stored in a hydrocarbon fuel storage vessel when the solid oxide regenerative fuel cell is operated in the electrolysis mode.

27. The system of claim 26, further comprising:

a third means for providing power to a power distribution system when the solid oxide regenerative fuel cell is operated in a fuel cell mode; and

wherein the fuel cell system comprises both the first means and the second means.

28. The system of claim 27, wherein the system is located in at least one of the following locations selected from a group consisting of a high altitude aircraft that is adapted to operate in an airless environment, a terrestrial orbit space craft that is adapted to operate in an airless environment, an underground location that lacks access to atmospheric air, an underwater location that lacks access to atmospheric air and a building at least a portion of which can be sealed from outside atmosphere.

29. A method of generating power and oxygen using a terrestrial power and oxygen generation system, comprising:

operating a solid oxide regenerative fuel cell in a fuel cell mode to generate power;

operating the solid oxide regenerative fuel cell in an electrolysis mode to generate oxygen and fuel; and

providing the oxygen generated by the solid oxide regenerative fuel cell to a life support system.

30. The method of claim 29, wherein:

the step of operating a solid oxide regenerative fuel cell in the fuel cell mode comprises providing oxygen and a hydrocarbon fuel to the fuel cell and releasing carbon dioxide and water vapor from the solid oxide regenerative fuel cell; and

the step of operating a solid oxide regenerative fuel cell in the electrolysis mode comprises providing power, carbon dioxide and water vapor to the solid oxide regenerative fuel cell and generating oxygen and a hydrocarbon fuel.

31. The method of claim 30, further comprising storing the oxygen generated by the solid oxide regenerative fuel cell in the electrolysis mode in a liquid state in an oxygen storage vessel and providing the oxygen to the life support system from the oxygen storage vessel.

32. The method of claim 31, wherein:

the carbon dioxide provided to the solid oxide regenerative fuel cell is generated by living beings being supported by the life support system; and

the hydrocarbon fuel comprises methane stored in a liquid state in a fuel storage vessel.

33. The method of claim 31, further comprising:

recovering hydrogen from the solid oxide regenerative fuel cell in electrolysis mode;

reacting the recovered hydrogen with carbon monoxide to generate water vapor and methane; and

storing the generated methane in a fuel storage vessel.

34. The method of claim 31, further comprising:

recovering hydrogen from the solid oxide regenerative fuel cell anode side output and providing the recovered hydrogen into the hydrocarbon fuel input into the solid oxide regenerative fuel cell when the solid oxide regenerative fuel cell is operated in the fuel cell mode; and

separately recovering water vapor from the solid oxide regenerative fuel cell anode side output and providing the recovered water vapor into the hydrocarbon fuel input into the solid oxide regenerative fuel cell when the solid oxide regenerative fuel cell is operated in the fuel cell mode.

35. The method of claim 29, wherein the life support system and the solid oxide regenerative fuel cell are located in at least one of the following locations selected from a group consisting of a high altitude aircraft that is adapted to operate in an airless environment, a terrestrial orbit space craft that is adapted to operate in an airless environment, an underground location that lacks access to atmospheric air and an underwater location that lacks access to atmospheric air.

36. The method of claim 29, wherein:

the life support system and the solid oxide regenerative fuel cell are located in a building;

the solid oxide regenerative fuel cell operates in the electrolysis mode and provides oxygen to the life support system when at least a portion of the building is sealed from outside atmosphere; and

the solid oxide regenerative fuel cell provides power to the building in the fuel cell mode and waste heat in the fuel cell and electrolysis modes for at least one building appliance.

37. The method of claim 29, further comprising:

operating the solid oxide fuel cell in the electrolysis mode at a first rate of electrolysis to recharge spent fuel and oxygen and to provide oxygen to a life support system; and

operating the solid oxide fuel cell in the electrolysis mode at a second rate of electrolysis less than the first rate after the spent fuel and oxygen have been recharged to provide oxygen to a life support system.

38. The method of claim 37, wherein:

wherein the life support system and the solid oxide regenerative fuel cell are located in an underwater vehicle; and

the underwater vehicle lacks a diesel engine and lacks a battery which provides power to a propulsion system of the underwater vehicle.

39. The method of claim 38, further comprising heating the underwater vehicle using heat generated from operating the solid oxide regenerative fuel cell.

40. The method of claim 38, further comprising liquefying carbon dioxide using heat for vaporizing oxygen and methane in the fuel cell mode.

41. The method of claim 38, wherein:

the solid oxide regenerative fuel cell is operated in the electrolysis mode when the underwater vehicle operates with power provided from a primary power generator; and

the solid oxide regenerative fuel cell is operated in the fuel cell mode when the underwater vehicle operates with the primary power generator turned off.

42. The method of claim 41, wherein:

the underwater vehicle leaves port with an oxygen storage vessel about full, a hydrocarbon storage vessel partially full and a carbon dioxide storage vessel about empty;

the primary power generator provides power to the solid oxide regenerative fuel cell in the electrolysis mode to generate and store oxygen and hydrocarbon fuel;

the stored oxygen and hydrocarbon fuel are used to generate power and to generate and store carbon dioxide when the solid oxide regenerative fuel cell operates in the fuel cell mode; and

the underwater vehicle returns to port with the oxygen storage vessel about full, the hydrocarbon storage vessel about full and the carbon dioxide storage vessel about full.

43. A method of generating power, comprising:

providing power to a solid oxide regenerative fuel cell from an external power source when power demand on the external power source is below a predetermined amount;

operating the solid oxide regenerative fuel cell in an electrolysis mode using the power provided from the external power source;

generating and storing a hydrocarbon fuel while the solid oxide regenerative fuel cell operates in the electrolysis mode;

providing the stored hydrocarbon fuel and oxygen to the solid oxide regenerative fuel cell;

operating the solid oxide regenerative fuel cell in a fuel cell mode using the provided fuel and oxygen; and

providing power from the solid oxide regenerative fuel cell operating in the fuel cell mode to the external power source when power demand on the external power source is above the predetermined amount or when the external power source experiences a power disruption.

44. The method of claim 43, wherein the external power source comprises a power grid.

45. The method of claim 44, wherein the hydrocarbon fuel comprises a methane fuel.

46. The method of claim 45, wherein:

the power is provided to the solid oxide regenerative fuel cell from the power grid when power demand on the power grid is below a peak load on the power grid; and

the power is provided from the solid oxide regenerative fuel cell operating in the fuel cell mode to the power grid when power demand on the power grid is above the peak load on the power grid.

47. The method of claim 46, wherein

the power is provided to the solid oxide regenerative fuel cell from the power grid during night time;

and

the power is provided from the solid oxide regenerative fuel cell operating in the fuel cell mode to the power grid during day time.

48. The method of claim 44, wherein the power is provided from the solid oxide regenerative fuel cell operating in the fuel cell mode to the power grid when the power grid experiences a power outage.

49. The method of claim 43, wherein:

the solid oxide regenerative fuel cell is located in a building;

the solid oxide regenerative fuel cell operates in the electrolysis mode and provides oxygen to a life support system when at least a portion of the building is sealed from outside atmosphere; and

the solid oxide regenerative fuel cell provides power to the building in a fuel cell mode and waste heat in the fuel cell and electrolysis modes for at least one building appliances.