Claims
- 1. A method of starting a solid oxide fuel cell system, comprising:pressurizing a main plenum to a first pressure, wherein said main plenum comprises a first supply of fuel, blowers, and air control valves; directing said first supply of fuel and a first supply of air to a preheated micro-reformer; creating a heated pre-reformate in said micro-reformer; discharging said heated pre-reformate from said micro-reformer to a main reformer; preheating said main reformer with said preheated pre-reformate; introducing a second supply of fuel and a second supply of air to said main reformer; creating a heated main reformate in said main reformer; directing said heated main reformate to a waste energy recovery assembly; heating a cathode supply in said waste energy recovery system; and directing said heated cathode supply to heat said solid oxide fuel cell stack.
- 2. The method of claim 1, wherein said solid oxide fuel cell stack is at an ambient temperature of about −40° C. to about 50° C., and is heated to a temperature of up to about 120° C.
- 3. The method of claim 1, further comprising directing said heated pre-reformate and said heated main reformate through a reformate control valve.
- 4. The method of claim 1, further comprising electrically preheating said micro-reformer.
- 5. The method of claim 1, further comprising monitoring said heated main reformate with a sensor selected from the group consisting of pressure sensors, temperature sensors, and combinations comprising at least one of the foregoing sensors.
- 6. The method of claim 1, further comprising directing said heated pre-reformate and said heated main reformate through said waste energy recovery assembly to said solid oxide fuel cell stack.
- 7. A method of transitioning a solid oxide fuel cell system to normal operating conditions, comprising:operating a main reformer to produce a reformate; directing said reformate in a first stream and second stream to a waste energy recovery assembly; catalytically combusting said first stream of said reformate in said waste energy recovery assembly; producing thermal energy in said waste energy recovery assembly to heat said second stream of said reformate and a supply of air; directing said second stream of said reformate and said supply of air to a solid oxide fuel cell stack; and heating said solid oxide fuel cell stack to a temperature of about 600° C. or greater.
- 8. The method of claim 7, further comprising directing said reformate through a reformate control valve.
- 9. The method of claim 7, wherein said solid oxide fuel cell stack is at a temperature of about 120° C. or greater and is heated to a temperature of about 600° C. to about 1,000° C.
- 10. The method of claim 9, wherein said solid oxide fuel cell stack is heated to about 650° C. to about 800° C.
- 11. A method of operating a solid oxide fuel cell system, comprising:directing a supply of reformate from a waste energy recovery assembly to a solid oxide fuel cell stack; using said supply of reformate and a supply of air in said solid oxide fuel cell stack; producing electrical energy in said solid oxide fuel cell stack; harnessing said electrical energy; sensing a condition of said reformate; and adjusting said supply of reformate and/or said supply of air, based upon said condition, to meet a demand by a vehicle for said electrical energy.
- 12. The method of claim 11, wherein said condition is selected from the group consisting of temperature, pressure sensor, gas content, and combinations comprising at least one of the foregoing conditions.
- 13. A method of shutting down a solid oxide fuel cell system, comprising:maintaining a supply of air to a solid oxide fuel cell stack and at least one thermal enclosure; decreasing a supply of reformate to said solid oxide fuel cell stack; stopping said supply of reformate after an anode oxidation period has passed; and stopping said supply of air to said solid oxide fuel cell stack.
- 14. The method of claim 13, further comprising maintaining said supply of reformate at a sufficient flow to prevent anode oxidation during said anode oxidation period.
- 15. The method of claim 13, wherein said solid oxide fuel cell stack is to about 200° C. or less.
- 16. The method of claim 13, further comprising cooling a system enclosure with said supply of air to a temperature of about 45° C. or less.
- 17. The method of claim 13, further comprising exhausting stored thermal energy through a waste energy recovery assembly with said supply of air.
- 18. A method of operating a solid oxide fuel cell system, comprising:directing a supply of reformate and a supply of air to a solid oxide fuel cell stack; operating said solid oxide fuel cell stack; reducing said supply of reformate and said supply of air to said solid oxide fuel cell stack; and maintaining said solid oxide fuel cell stack at a standby temperature of about 400° C. to about 600° C.
- 19. The method of claim 18, further comprising transitioning said solid oxide fuel cell system from said standby temperature to an operating of about 600° C. or less based upon a vehicle load request.
- 20. A solid oxide fuel cell mechanization for a transportation vehicle, comprising:a solid oxide fuel cell stack; a reformer system disposed in fluid communication with said solid oxide fuel cell stack, wherein said reformer system comprises a main reformer and a micro-reformer; a waste energy recovery assembly disposed in fluid communication with said solid oxide fuel cell stack and said reformer system; a system enclosure disposed around said solid oxide fuel cell stack, said waste energy recovery assembly, and said reformer system; a thermal management system disposed within said system enclosure, wherein said thermal management system comprises a main plenum and an insulation plenum enclosing a chamber, said chamber comprising said solid oxide fuel cell stack, said reformer system, and said waste energy recovery system; and a process air supply disposed in fluid communication with said thermal management system.
- 21. The mechanization of claim 20, wherein said micro-reformer and said main reformer are partial oxidation reformers.
- 22. The mechanization of claim 20, wherein said insulation plenum comprises an active porous insulation.
- 23. The mechanization of claim 20, further comprising a plenum bulkhead disposed in contact with said main plenum and said insulation plenum.
- 24. The mechanization of claim 20, further comprising a main blower, air control valves, and an actuator in said main plenum.
- 25. The mechanization of claim 20, further comprising an enclosure lid cooling air passage in thermal communication with said main plenum.
- 26. The mechanization of claim 20, further comprising a reformate control valve in fluid communication with said reformer system.
CROSS-REFERENCE TO RELATED APPLICATION
The present application claims the benefit of the date of U.S. Provisional Application No. 60/201,568, filed on May 1, 2000, which is incorporated herein in its entirety.
US Referenced Citations (9)
Provisional Applications (1)
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Number |
Date |
Country |
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60/201568 |
May 2000 |
US |