Device and Method for Converting Thermal Energy into Electrical Energy

• US 20080303375A1
• Filed: 06/06/2008
• Published: 12/11/2008
• Est. Priority Date: 06/08/2007
• Status: Active Grant

• Current Assignee: Carver Scientific Inc.
• Original Assignee: David Reginald Carver
• Inventors: Carver, David Reginald
• Granted Patent: US 7,816,601 B2
• Time in Patent Office: Days
• US Class Current: 310/306
• CPC Class Codes: F25B 21/00 Machines, plants or systems, using electric or magnetic effects
• CPC Class Codes: H10N 15/00 Thermoelectric devices without a junction of dissimilar materials; Thermomagnetic devices, e.g. using the Nernst-Ettingshausen effect integrated devices or assemblies of multiple devices H10N19/00
• CPC Class Codes: Y02B 30/00 Energy efficient heating, ventilation or air conditioning [HVAC]

Abstract

A device and method for using a field-responsive material that changes temperature when subjected to a respective field in combination with a thermal to electrical energy converter to accomplish the generation of electrical energy. The field-responsive material, such as an electrocaloric or magnetocaloric material, changes temperature when subjected to a change in a respective electric or magnetic field. The changing field applied to the field-responsive material causes a temperature change in the field-responsive material to heat or cool the field-responsive material. A thermal to electrical energy converter is in thermal contact with the field-responsive material, such that temperature changes in the field-responsive material in turn changes the temperature of the thermal to electrical energy converter, which the converter then converts into electrical energy. In this manner, the application of an appropriate electric or magnetic field can be utilized to generate thermal energy changes that can be converted into electrical energy.

Claims

1. A thermal-to-electrical energy conversion method, comprising:

(a) subjecting a field-responsive material to at least one of an electrical and magnetic field to induce a temperature change in the field-responsive material;

(b) creating a temperature change in at least one thermal to electrical energy conversion component in thermal contact with the field-responsive material based on the temperature change in the field-responsive material;

(c) creating electrical energy in the at least one thermal to electrical energy conversion component based upon the temperature change experienced by the thermal to electrical energy conversion component and outputting the electrical energy created;

(d) removing the field from the field-responsive material to allow the field-responsive material and the at least one thermal to electrical energy conversion component to approach thermal equilibrium;

(e) repeating steps (a)-(d) to repeatedly create and output electrical energy.

2. The method of claim 1, wherein the field-responsive material includes an electrocaloric material.

3. The method of claim 1, wherein the field-responsive material includes an magnetocaloric material.

4. The method of claim 1, further comprising applying a time-varying alternating field as the at least one of an electrical and magnetic field.

5. The method of claim 1, further comprising:

creating electrical energy in the form of an AC electrical current;

storing the AC electrical current in an energy capture component that captures electrical flow from the at least one thermal to electrical energy conversion component.

6. The method of claim 1, further comprising:

creating a temperature change in a plurality of thermal to electrical energy conversion components that are in thermal contact with the field-responsive material based on the temperature change in the field-responsive material;

creating electrical energy in the plurality of thermal to electrical energy conversion components based upon the temperature change experienced by the thermal to electrical energy conversion component and outputting the electrical energy created;

removing the field from the field-responsive material to allow the field-responsive material and the plurality of thermal to electrical energy conversion components to approach thermal equilibrium.

7. The method of claim 6, wherein the plurality of thermal to electrical energy conversion components include thermal to electrical energy conversion components that are respectively adjacent to different portions of the field-responsive material.

8. The method of claim 6, wherein the plurality of thermal to electrical energy conversion components include thermal to electrical energy conversion components that are interconnected together in a stacked head-to-toe relationship such that the electrical energy output by each thermal to electrical energy conversion component is combined together to produce a combined electrical energy output.

9. The method of claim 1, further comprising assisting in the achievement of thermal equilibrium by allowing thermal energy to pass from a heat exchanger in thermal contact with the thermal to electrical energy conversion component to pass through to the field-responsive material.

10. The method of claim 1, wherein the thermal to electrical energy conversion component includes at least one of a thermocouple material, a Thomson effect material and a pyroelectric material.

11. The method of claim 1, further comprising generating the at least one of an electrical and magnetic field with a resonant circuit having at least 75% efficiency per cycle.

26. The device of claim 1, wherein the field generator includes a resonant circuit having at least 75% efficiency per cycle when generating at least one of an electrical and magnetic field.

33. The method of claim 1, wherein the electrical energy created and output by the at least one thermal to electrical energy conversion component is greater than the electrical energy required to produce the at least one of an electrical and magnetic field.

34. The method of claim 1, further operating a comparator circuit to governs additional power necessary for the generation of a time-varying alternating field using feedback received from the device.

12. A thermal-to-electrical energy conversion device, comprising:

a field generator for generating a time-varying alternating field;

a field-responsive material that changes temperature when subjected to at least one of an electrical and magnetic field;

at least one thermal to electrical energy conversion component in thermal contact with the field-responsive material that changes temperature based on a temperature change of the field-responsive material, wherein the at least one thermal to electrical energy conversion component creates electrical energy based upon the temperature change experienced by the thermal to electrical energy conversion component and outputs the electrical energy created;

an energy accumulator arranged to receive and store the electrical energy created by the thermal to electrical energy conversion component.

13. The device of claim 12, wherein the field-responsive material includes an electrocaloric material.

14. The device of claim 12, wherein the field-responsive material includes an magnetocaloric material.

15. The device of claim 12, wherein the time-varying alternating field comprises at least one of an electrical and magnetic field.

16. The device of claim 12, wherein the electrical energy is created in the form of an AC electrical current.

17. The device of claim 12, further comprising a plurality of thermal to electrical energy conversion components that are each in thermal contact with the field-responsive material at different respective locations with respect to the field-responsive material.

18. The device of claim 12, wherein the field generator includes a pair of layers of conductive metal material connected to a power source, such that the field-responsive material is positioned between the pair of layers of conductive metal material so that the field-responsive material is subjected to an electric field generated by the layers of conductive metal material.

19. The device of claim 18, wherein the at least one thermal to electrical energy conversion component comprises at least one layer of material that generates electrical energy in response to a temperature change that is formed adjacent to and in thermal contact with one of the layers of conductive metal material.

20. The device of claim 19, wherein the at least one thermal to electrical energy conversion component comprises two layers of dissimilar material that exhibit a thermocouple effect.

21. The device of claim 19, further comprising:

a first thermal to electrical energy conversion component comprising at least one layer of material that generates electrical energy in response to a temperature change formed adjacent to and in thermal contact with one of the layers of conductive metal material; and

a second thermal to electrical energy conversion component comprising at least one layer of material that generates electrical energy in response to a temperature change formed adjacent to and in thermal contact with the other of the layers of conductive metal material.

22. The device of claim 17, wherein the plurality of thermal to electrical energy conversion components include thermal to electrical energy conversion components that are interconnected together in a stacked head-to-toe relationship such that the electrical energy output by each thermal to electrical energy conversion component is combined together to produce a combined electrical energy output.

23. The device of claim 22, wherein the plurality of thermal to electrical energy conversion components include pairs of segments of layers of dissimilar material that are formed in a stacked relationship that exhibit a thermocouple effect, wherein each of the pairs of segments are arranged side-by-side to one another in a head-to-toe relationship and adjacent to and in thermal contact with one of the layers of conductive metal material.

24. The device of claim 12, further comprising a heat exchanger in thermal contact with the thermal to electrical energy conversion component arranged to pass heat from the heat exchanger through the thermal to electrical energy conversion component to the field-responsive material to assist in returning the field-responsive material to thermal equilibrium when not subjected to a field.

25. The device of claim 12, wherein the thermal to electrical energy conversion component includes at least one of a thermocouple material, a Thomson effect material and a pyroelectric material.

27. The device of claim 12, wherein the field-responsive material is formed to possess a tubular shape.

28. The device of claim 27, wherein the field generator includes a conductive wire wound around the tubular field-responsive material and to a power source, such that the field-responsive material is subjected to a magnetic field generated by the wound conductive wire.

29. The device of claim 28, wherein the at least one thermal to electrical energy conversion component is formed to possess a tubular shape.

30. The device of claim 27, wherein each least one thermal to electrical energy conversion component is formed to possess a shape including first portion having a larger diameter and a second portion having a smaller diameter, wherein a cavity is formed with a cavity internal to the first portion, the device further comprising a plurality of thermal to electrical energy conversion components that are arranged in a nested arrangement with the second portion of each thermal to electrical energy conversion component fitting within the cavity of the first portion of an adjacent thermal to electrical energy conversion component.

31. The device of claim 12, wherein the electrical energy received and stored at the energy accumulator is greater than the electrical energy required to produce the time-varying alternating field.

32. The device of claim 12, further comprising a comparator circuit that governs additional power necessary for the generation of the time-varying alternating field using feedback received from the device.