Systems and methods for converting heat to electrical power

• US 7,446,451 B2
• Filed: 06/29/2004
• Issued: 11/04/2008
• Est. Priority Date: 06/29/2004
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Allen, Edward H., Karageorgis, Markos
• Primary Examiner(s): Dougherty; Thomas M
• Application Number:
  US10/881,890
• Publication Number:
  US 20050284147A1
• Time in Patent Office: 1,589 Days
• Field of Search: 310311-371, 310/800, 136/253
• US Class Current: 310/311
• CPC Class Codes: B64B 1/14 Outer covering
• CPC Class Codes: H01L 31/0352 characterised by their shape or by the shapes, relative sizes or disposition of the semiconductor regions
• CPC Class Codes: H01L 31/035281 Shape of the body
• CPC Class Codes: H02N 2/18 producing electrical output from mechanical input, e.g. generators for measurement devices G01
• CPC Class Codes: H02S 99/00 Subject matter not provided for in other groups of this subclass
• CPC Class Codes: Y02E 10/46 Conversion of thermal power into mechanical power, e.g. Rankine, Stirling or solar thermal engines
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy

Abstract

An apparatus includes a thermo-photovoltaic (TPV) material that is capable of generating electrical power from low temperature heat radiation. An electric field generator is coupled to apply an electric field to the TPV material. The strength of the electric field is sufficient to shift the sensitivity of the TPV material to sense lower frequency radiation than the TPV material can sense when the electric field is not applied and to broaden the band of frequencies over which the TPV is effective.

Claims

1. An apparatus comprising:

a thermo-photovoltaic (TPV) fiber configured to generate electrical power from heat radiation; and

an electric field generator coupled to apply an electric field to the TPV fiber, wherein the strength of the electric field is sufficient to shift the sensitivity of the TPV fiber to sense lower frequency radiation than the TPV fiber can sense when the electric field is not applied and to broaden the range of frequencies over which the TPV fiber is sensitive.

2. The apparatus of claim 1, wherein the electric field generator includes a piezoelectric material.

3. The apparatus of claim 1, wherein the electric field generator includes at least one of a capacitor and an electrode.

4. The apparatus of claim 1, wherein the TPV fiber includes quantum structures.

5. The apparatus of claim 2, further comprising an actuating system configured to modulate the current flowing through the TPV fiber.

6. The apparatus of claim 5, wherein the actuating system generates an energy beam.

7. The apparatus of claim 6, wherein the energy beam is generated by a laser.

8. The apparatus of claim 6, wherein the energy beam is generated by a maser.

9. The apparatus of claim 6, wherein the energy beam is ultrasonic.

10. The apparatus of claim 1, further comprising a power generation controller coupled to the electric field generator, wherein the power generation controller is configured to receive signals representing the electrical power generated by the TPV fiber and to adjust the electric field generator based on power required.

11. The apparatus of claim 1, further comprising an energy storage facility configured to store excess energy from the TPV fiber.

12. The apparatus of claim 1, further comprising a special-purpose fiber interwoven with the TPV fiber, wherein the special-purpose fiber provides desired structural capabilities.

13. The apparatus of claim 1, further comprising a special-purpose fiber interwoven with the TPV fiber, wherein the special-purpose fiber includes a sensor component.

14. The apparatus of claim 1, further comprising an electrically conductive filament threaded through the TPV fiber.

15. The apparatus of claim 1, further comprising a plurality of TPV fiber segments, wherein each TPV fiber segment can be configured to provide power independently of the other TPV fiber segments.

16. The apparatus of claim 6, wherein the energy beam is applied to the TPV fiber to generate radio frequency (RF) waves and to impose a signal on the RF waves.

17. The apparatus of claim 1, further comprising:

an airship system, the TPV fiber is incorporated into fabric covering at least a portion of the airship system.

18. The apparatus of claim 1, further comprising the TPV fiber is interwoven with another fiber that has insulating properties to help reduce electromagnetic interference between adjacent TPV fibers.

19. The apparatus of claim 1, further comprising at least two segments of TPV fibers are incorporated in a device and configured to supply power to a component in the device.

20. The apparatus of claim 1, further comprising at least two segments of the TPV fiber electrically isolated from each other so that power remains available in the event that damage to one segment causes an open circuit condition.

21. The apparatus of claim 1, further comprising:

an engine, at least a portion of the engine is configured with the TPV fiber, the TPV fiber is used to withdraw heat from sections of an engine to reduce the work required of any compressor stages following the point of heat withdrawal.