Cryogenic power extraction

Patent metadata

Field	Value
Publication number	US-10480353-B2
Application number	US-201515119655-A
Country	US
Kind code	B2
Filing date	Feb 17, 2015
Priority date	Feb 21, 2014
Publication date	Nov 19, 2019
Grant date	Nov 19, 2019

Abstract

Various examples are provided for cryogenic power extraction. In one example, among others, a system for cryogenic power extraction includes a heat exchanger that can heat a cryogenic working fluid using exhaust heat from a heat source, and a turbine that can generate power from the heated cryogenic working fluid. In another example, a method includes heating a cryogenic working fluid with waste heat from a heat source and driving a turbine with the heated cryogenic working fluid. Power produced by the turbine can be used drive a mechanical load and/or generate electricity for use by an electrical load. For example, waste heat from a combustion engine of a vehicle can be used to generate power for driving mechanical loads of the engine and/or to generate electricity for charging a battery of the vehicle.

First claim

Therefore, at least the following is claimed:

1. A system for cryogenic power extraction, comprising:
a first heat exchanger configured to heat a cryogenic working fluid using exhaust heat from a heat source, wherein the cryogenic working fluid is liquid nitrogen (LN2);
a second heat exchanger configured to heat the cryogenic working fluid using coolant heated by residual heat of the heat source after operation of the heat source has been stopped, the coolant circulated through the second heat exchanger and the heat source by a pump; and
a turbine configured to generate power from the heated cryogenic working fluid, wherein the pump continues to circulate of the coolant after the operation of the heat source has been stopped using power generated by the turbine from the residual heat of the heat source.

2. The system of claim 1 , wherein gas converted from the LN2 heated by the exhaust heat is exhausted to atmosphere after passing through the turbine.

3. The system of claim 1 , wherein the heat source is a combustion engine.

4. The system of claim 3 , wherein the system is in a vehicle including the combustion engine.

5. The system of claim 4 , wherein the vehicle is a hybrid electric car.

6. The system of claim 4 , wherein the generated power charges a battery of the vehicle.

7. The system of claim 4 , wherein the generated power drives a mechanical load of the vehicle.

8. The system of claim 1 , wherein the heat source is a combustion engine, and the first heat exchanger heats the cryogenic working fluid using the exhaust heat generated during operation of the combustion engine.

9. The system of claim 8 , wherein the first heat exchanger heats the cryogenic working fluid using residual exhaust heat from the combustion engine after operation of the combustion engine has been stopped.

10. The system of claim 4 , further comprising an air cooling heat exchanger configured to cool air with the cryogenic working fluid, where the air is supplied for air conditioning of the vehicle.

11. The system of claim 1 , further comprising a coolant loop configured to obtain at least a portion of the exhaust heat from the heat source and provide the portion of the exhaust heat to the first heat exchanger.

12. The system of claim 11 , wherein the coolant loop utilizes glycol to transport the portion of the exhaust heat from the heat source to the first heat exchanger.

13. The system of claim 1 , further comprising a storage tank configured to store the cryogenic working fluid, the cryogenic working fluid provided from the storage tank to the first or second heat exchanger at a head pressure generated by ambient temperature.

14. The system of claim 13 , further comprising an adjustable throttle valve configured to regulate the cryogenic working fluid supplied from the storage tank to the first or second heat exchanger, wherein power generation by the turbine is controlled by adjustment of the adjustable throttle valve.

15. The system of claim 14 , further comprising control circuitry configured to monitor operating conditions of the system and regulate the adjustable throttle valve based at least in part upon the monitored operating conditions.

16. The system of claim 3 , further comprising a precooling heat exchanger configured to cool ambient air supplied to the combustion engine with the cryogenic working fluid before the cryogenic working fluid is supplied to the first or second heat exchanger, the cooled ambient air directed from the precooling heat exchanger to the combustion engine.

Assignees

• Univ Florida

Inventors

• Cook Charles R
• Lear Jr William E

Classifications

• F01D15/10

  Adaptations for driving, or combinations with, electric generators · CPC title

• F01K5/02

  used in regenerative installation · CPC title

• F01K23/101 Primary

  Regulating means specially adapted therefor (F01K23/105, F01K23/108 take precedence) · CPC title

• F17C9/04

  Recovery of thermal energy · CPC title

• F01D15/005 Primary

  Adaptations for refrigeration plants · CPC title