Thermal Energy Storage Apparatus

• US 20150114591A1
• Filed: 03/14/2013
• Published: 04/30/2015
• Est. Priority Date: 04/23/2012
• Status: Active Grant

• Current Assignee: Energy Technologies Institute LLP
• Original Assignee: Isentropic, Ltd.
• Inventors: Howes, Jonathan Sebastian, Macnaghten, James, Hunt, Rowland Geoffrey, Bennett, Robert Geoffrey, Wilson, Alexander Bruce
• Granted Patent: US 9,970,715 B2
• Time in Patent Office: Days
• US Class Current: 165/10
• CPC Class Codes: F28D 17/02 using rigid bodies, e.g. of porous material
• CPC Class Codes: F28D 20/0056 using solid heat storage material F28D20/0052 takes precedence
• CPC Class Codes: F28D 2020/0065 Details, e.g. particular heat storage tanks, auxiliary members within tanks
• CPC Class Codes: Y02E 60/14 Thermal energy storage

Abstract

A thermal energy store comprising a chamber having a gas inlet and a gas outlet and a plurality of successive, downstream, gas permeable thermal storage layers disposed between them, each layer comprising gas permeable thermal storage media, the store being configured for gas flow from the gas inlet to gas outlet through the layers for transfer of thermal energy to or from the thermal storage media, wherein at least one of the layers is a valved layer provided with at least one valve operable selectively to allow or prevent at least some gas flow through that layer via the valve so as to bypass the thermal storage media. A control system may selectively alter the flow path of the gas flowing from inlet to outlet in response to the progress of a thermal front, so as to bypass thermal storage layers upstream of the thermal front, where transfer is complete, or downstream thereof, where transfer is minimal.

Claims

1. A thermal energy store comprising:

a chamber having a gas inlet and a gas outlet; and

a plurality of successive, downstream, gas permeable thermal storage layers disposed between the inlet and the outlet,

each thermal storage layer comprising gas permeable thermal storage media, the store being configured for gas flow from the gas inlet to gas outlet through the plurality of thermal storage layers for transfer of thermal energy to or from the thermal storage media, wherein at least one layer of the plurality of thermal storage layers is a valved layer having at least one valve operable selectively to allow or prevent at least some gas flow through the at least one layer via the valve so as to bypass the thermal storage media.

2. A thermal energy store according to claim 1, wherein the valved layer is provided with a plurality of spaced valves.

3. A thermal energy store according to claim 2, wherein the spaced valves in the valved layer are operable independently of those in any other valved layer.

4. A thermal energy store according to claim 1, wherein each thermal storage layer of the plurality of thermal storage layers comprises a respective valved layer.

5. A thermal energy store according to claim 1, further comprising a control system configured to selectively alter a flow path of gas flowing from inlet to outlet in response to progress of a thermal front through the store.

9. A thermal energy store according to claim 1, wherein the chamber is an upright chamber comprising a plurality of horizontal gas permeable thermal storage layers arranged above one another in between the gas inlet and the gas outlet such that the store is configured for vertical gas flow from the gas inlet to the gas outlet through the thermal storage layers.

10. A thermal energy store according to claim 9, wherein the store is arranged such that the gas inlet is provided at the top of the chamber when the gas inlet is set up as a hot inlet or at the bottom of the chamber when the gas inlet is set up as a cold inlet.

11. A thermal energy store according to claim 1, further comprising a gap or plenum for lateral gas distribution above the thermal storage media of each layer.

12. A thermal energy store according to claim 1, wherein the plurality of thermal storage layers are in the form of a layered support assembly in which the thermal storage media of each layer is supported by the support assembly, and the assembly is constructed such that the thermal storage layers are mounted on top of each other to form a stack.

14. A thermal energy store according to claim 1, wherein the valved layer comprises at least one actuating mechanism for the at least one valve arranged above the thermal storage media.

15. A thermal energy store according to claim 12, wherein the valved layer comprises at least one actuating mechanism for the at least one valve, which mechanism is housed externally of the support assembly.

16. A thermal energy store according to claim 1, wherein the valved layer comprises a plurality of valves operable in unison by a single actuation mechanism.

17. A thermal energy store according to claim 1, wherein the at least one valve comprises a flap valve or a sliding valve.

20. A thermal energy store according to claim 1, wherein the plurality of thermal storage layers comprise adjacent valved layers, each adjacent valved layer comprising a respective valve, and wherein the respective valves in the adjacent valved layers are vertically aligned to provide bypass passageways extending through the store.

22. An energy storage system comprising one or more thermal energy stores according to claim 1.

23. A pumped heat electricity storage (PHES) system according to claim 22, comprising:

a compression stage to compress gas;

a first thermal store to receive and store thermal energy from gas compressed by the compression stage;

an expansion stage to receive gas after exposure to the first thermal store and expanding the gas; and

,

a second thermal store to transfer thermal energy to gas expanded by the expansion stage.

97. A thermal energy store according to claim 5, wherein the control system is configured to alter the flow path of the gas to bypass thermal storage layers of the plurality of thermal storage layers upstream of the thermal front, wherein thermal transfer in the thermal storage layers is substantially complete.

98. A thermal energy store according to claim 5, wherein the control system is configured to alter the flow path of the gas to bypass thermal storage layers of the plurality of thermal storage layers downstream of the thermal front, wherein thermal transfer in the thermal storage layers is minimal.

99. A thermal energy store according to claim 5, wherein:

the control system is configured to alter the flow path of the gas to bypass upstream thermal storage layers of the plurality of thermal storage layers upstream of the thermal front;

thermal transfer in the upstream thermal storage layers is substantially complete;

the control system is configured to bypass downstream thermal storage layers of the plurality of thermal storage layers downstream of the thermal front; and

thermal transfer in the downstream thermal storage layers is minimal,

such that the flow path of the gas only passes through those thermal storage layers of the plurality of thermal storage layers in which all or part of the thermal front exists.

6-8. -8. (canceled)

13. (canceled)

18. (canceled)

19. (canceled)

21. (canceled)

24-96. -96. (canceled)

100. A method of operating a thermal energy store, the method comprising:

directing gas into a gas inlet of a chamber comprising the gas inlet, a gas outlet, and a plurality of successive downstream, gas permeable, thermal storage layers disposed between the gas inlet and the gas outlet and comprising gas permeable thermal storage media, such that the gas flows from the gas inlet to the gas outlet through the plurality of thermal storage layers for transfer of thermal energy to or from the thermal storage media and a thermal front progresses along the length of the store;

wherein the plurality of thermal storage layers comprise adjacent valved layers, each respective layer of the adjacent valved layers comprising at least one valve that is selectively operable to allow or prevent at least some gas flow through the respective layer so as to bypass the respective thermal storage media of the respective layer; and

,

diverting the gas flow into different selected downstream groups of adjacent valved layers, in turn, as the thermal front moves downstream, by closing the valves of those selected groups of adjacent valved layers in turn.