SYSTEMS, APPARATUS AND METHODS FOR THERMAL ENERGY STORAGE, COUPLING AND TRANSFER

• US 20110083436A1
• Filed: 10/13/2010
• Published: 04/14/2011
• Est. Priority Date: 10/14/2009
• Status: Active Grant

• Current Assignee: Infinia Technology Corporation (American Superconductor Corporation)
• Original Assignee: Infinia Corporation (Qnergy Ltd.)
• Inventors: Brehm, Peter, White, Maurice
• Granted Patent: US 8,464,535 B2
• Time in Patent Office: Days
• US Class Current: 60/670
• CPC Class Codes: F01K 25/12 the vapours being metallic, e.g. mercury
• CPC Class Codes: F01K 3/08 Use of accumulators and the plant being specially adapted for a specific use
• CPC Class Codes: F03G 6/06 with solar energy concentrating means
• CPC Class Codes: F03G 6/068 having other power cycles, e.g. Stirling or transcritical, supercritical cycles; combined with other power sources, e.g. wind, gas or nuclear
• CPC Class Codes: F24S 20/20 Solar heat collectors for receiving concentrated solar energy, e.g. receivers for solar power plants
• CPC Class Codes: F24S 23/00 Arrangements for concentrating solar-rays for solar heat collectors
• CPC Class Codes: F24S 50/20 for tracking
• CPC Class Codes: F24S 60/10 using latent heat
• CPC Class Codes: F28D 20/02 using latent heat
• CPC Class Codes: F28D 20/021 the latent heat storage material and the heat-exchanging means being enclosed in one container F28D20/023 - F28D20/028 take precedence
• CPC Class Codes: F28D 20/025 the latent heat storage material being in direct contact with a heat-exchange medium or with another heat storage material F28D20/003 takes precedence
• CPC Class Codes: F28D 20/026 with different heat storage materials not coming into direct contact
• CPC Class Codes: Y02E 10/40 Solar thermal energy, e.g. solar towers
• CPC Class Codes: Y02E 10/44 Heat exchange systems
• 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 10/47 Mountings or tracking
• CPC Class Codes: Y02E 60/14 Thermal energy storage
• CPC Class Codes: Y02E 70/30 Systems combining energy storage with energy generation of non-fossil origin

Abstract

Systems, methods, and apparatus relating to the use of phase change material to store, transfer and convert heat, such as from solar radiation, to mechanical work or electricity. Apparatus, systems, components, and methods relating to thermal energy transfer and energy conversion are described herein. In one aspect, the invention relates to a containment vessel having a heat receiving region and a heat transfer region such that a plurality of phase change materials are disposed therein and a sequence of solid, liquid and vapor phases are used to transfer heat from a source to a heat receiver of a power conversion unit.

Claims

1. A thermal energy transfer system comprising:

a containment vessel defining a cavity comprising an inner surface an outer surface;

a first phase change material having a first liquid density disposed in the cavity;

a second phase change material having a second liquid density, the second phase change material disposed in the cavity and adjacent to and in contact with the first phase change material, wherein the second liquid density is less than the first liquid density;

a vapor space adjacent to and defined by the inner surface and the second phase change material; and

a heat receiver of a power conversion unit, the heat receiver disposed in the vapor space.

2. The thermal energy transfer system of claim 1 wherein the heat receiver is oriented within the containment vessel such that a vapor phase of the second phase change material condenses thereon.

3. The thermal energy transfer system of claim 1 further comprising a heat source interface in thermal communication with the first phase change material.

4. The thermal energy transfer system of claim 1 further comprising the power conversion unit.

5. The thermal energy transfer system of claim 1 wherein the first phase change material has a liquid density that is less than its solid density.

6. The thermal energy transfer system of claim 1 wherein the vapor space defines a vacuum or is filled with an inert gas.

7. The thermal energy transfer system of claim 4 wherein the power conversion unit is selected from the group consisting of a closed cycle heat engine, a Stirling engine, a Brayton cycle engine and a Rankine cycle engine.

8. The thermal energy transfer system of claim 3 wherein the heat source interface or heat source is selected from the group consisting of a subsurface of the outer surface of the containment vessel, a combustion engine exhaust, an industrial process or other waste heat stream, a manifold, a pipe, a plate, a finned structure, a dish concentrator, a trough concentrator, a heliostat, a reflector, a thermal energy storage unit, and a reactor.

9. The thermal energy transfer system of claim 1 wherein the first phase change material comprises a first material selected from the group consisting of a eutectic composition material;

a substantially pure composition material, NaF/NaCl, MgCl₂, NaF/CaF₂/MgF₂, KF/NaF/MgF₂, KF/NaF, KF/BeF₂, BeF₂, NaF/MgF₂, LiF/MgF₂, Li₂CO₃, LiH, LiF/NaF/MgF₂, LiF, NaCl/NiCl₂, LiOH/LiF, LiOH, LiF/LiCl, NaCl, KCl/NaCl, Na₂B₄O₇. NaF/MgF₂/Kf, NaF, BeF₂, LiCl/KCl, and wherein the second phase change material comprises a material selected from the group consisting of a eutectic material, a substantially pure composition material, Na, K, NaK, Li, Rb, Cs, S, Hg, Mg.

10. The thermal energy transfer system of claim 1 wherein when the containment vessel is heated, the first phase change material changes phase from a solid to a liquid and the second phase change material changes phase from a liquid to a vapor.

11. An electric power generating system comprising:

a power conversion unit comprising a thermal energy conversion system and a heat receiver in thermal communication with the thermal energy conversion system;

a containment vessel defining a cavity comprising an inner surface an outer surface;

a first phase change material having a first liquid density disposed in the cavity;

a second phase change material having a second liquid density, the second phase change material disposed in the cavity and adjacent to and in contact with the first phase change material, wherein the second liquid density is less than the first liquid density, and the second phase change material in thermal communication with the heat receiver;

a vapor space adjacent to and defined by the inner surface and the second phase change material, wherein the heat receiver is disposed in the vapor space; and

a heat source interface in thermal communication with the first phase change material.

12. The electric power generating system of claim 11 wherein the heat receiver is oriented within the containment vessel such that a vapor phase of the second phase change material condenses thereon.

13. The electric power generating system of claim 11 wherein the first phase change material has a liquid density that is less than its solid density.

14. The electric power generating system of claim 11 wherein the heat source or heat source interface is selected from the group consisting of a subsurface of the outer surface of the containment vessel, a combustion engine exhaust, an industrial process or other waste heat stream, a manifold, waste heat, a pipe, a plate, a finned structure, a dish concentrator, a trough concentrator, a heliostat, a reflector, a thermal energy storage unit, and a reactor.

15. The electric power generating system of claim 11 wherein the first phase change material comprises a eutectic composition material;

a substantially pure composition material, NaF/NaCl, MgCl₂, NaF/CaF₂/MgF₂, KF/NaF/MgF₂, KF/NaF, KF/BeF₂, BeF₂, NaF/MgF₂, LiF/MgF₂, Li₂CO₃, LiH, LiF/NaF/MgF₂, LiF, NaCl/NiCl₂, LiOH/LiF, LiOH, LiF/LiCl, NaCl, KCl/NaCl, Na₂B₄O₇. NaF/MgF₂/Kf, NaF, BeF₂, LiCl/KCl, and wherein the second phase change material comprises a material selected from the group consisting of a eutectic material, a substantially pure composition material, Na, K, NaK, Li, Rb, Cs, S, Hg, Mg.

16. The electric power generating system of claim 11 further comprising a solar concentrator positioned to direct solar energy upon the heat source interface, wherein the heat source interface is a portion of the outer surface of the containment vessel.

17. The electric power generating system of claim 11 wherein the heat source interface is a manifold having a first port and a second port, wherein the manifold displaces a volume of the first phase change material and the first and second ports are disposed in the outer surface of the containment vessel.

18. A method of transferring thermal energy between a heat source and a power conversion unit having a heat receiver, the method comprising the steps of:

transferring thermal energy from the heat source to a first phase change material disposed in a containment vessel;

transferring thermal energy to a second phase change material in the containment vessel using the first phase change material;

vaporizing the second phase change material; and

condensing the second phase change material on a heat receiver disposed in the containment vessel above the first phase change material such that thermal energy is transferred to the heat receiver.

19. The method of claim 18 wherein the temperature of the heat receiver is substantially uniform as a result of the heat transfer from the second phase change material.

20. The method of claim 18 further comprising the step of solidifying the first phase change material after transferring thermal energy to the first phase change material.

21. The method of claim 18 wherein the first phase change material comprises a eutectic composition material;

a substantially pure composition material, NaF/NaCl, MgCl₂, NaF/CaF₂/MgF₂, KF/NaF/MgF₂, KF/NaF, KF/BeF₂, BeF₂, NaF/MgF₂, LiF/MgF₂, Li₂CO₃, LiH, LiF/NaF/MgF₂, LiF, NaCl/NiCl₂, LiOH/LiF, LiOH, LiF/LiCl, NaCl, KCl/NaCl, Na₂B₄O₇. NaF/MgF₂/Kf, NaF, BeF₂, LiCl/KCl, and wherein the second phase change material comprises a material selected from the group consisting of a eutectic material, a substantially pure composition material, Na, K, NaK, Li, Rb, Cs, S, Hg, Mg.

22. The method of claim 18 further comprising the step of storing thermal energy in the first phase change material sufficient for powering the power conversion unit.

23. A thermal energy storage system comprising:

a containment vessel defining a cavity comprising an inner surface an outer surface;

a thermal energy storage medium comprising,

a thermal energy storage material having a first liquid density disposed in the cavity;

a phase change material having a second liquid density, the phase change material disposed in the cavity and adjacent to and in contact with the thermal energy storage material, wherein the second liquid density is less than the first liquid density;

a vapor space adjacent to and defined by the inner surface and the second phase change material; and

a heat receiver of a power conversion unit, the heat receiver disposed in the vapor space.

24. The thermal energy storage system of claim 23 wherein the energy storage medium stores sufficient thermal energy to power the power conversion unit from about 1 hour to about 24 hours.

25. The thermal energy storage system of claim 23 wherein the thermal energy storage material comprises a eutectic composition material;

a substantially pure composition material, NaF/NaCl, MgCl₂, NaF/CaF₂/MgF₂, KF/NaF/MgF₂, KF/NaF, KF/BeF₂, BeF₂, NaF/MgF₂, LiF/MgF₂, Li₂CO₃, LiH, LiF/NaF/MgF₂, LiF, NaCl/NiCl₂, LiOH/LiF, LiOH, LiF/LiCl, NaCl, KCl/NaCl, Na₂B₄O₇. NaF/MgF₂/Kf, NaF, BeF₂, LiCl/KCl, and wherein the phase change material comprises a material selected from the group consisting of a eutectic material, a substantially pure composition material, Na, K, NaK, Li, Rb, Cs, S, Hg, Mg.

26. The thermal energy storage system of claim 23 wherein the vapor space defines a vacuum or is filled with an inert gas.

27. The thermal energy storage system of claim 23 wherein the thermal energy storage material has a liquid density that is less than its solid density.