Compressed air energy storage system utilizing two-phase flow to facilitate heat exchange
View Patent ↗A compressed-air energy storage system according to embodiments of the present invention comprises a reversible mechanism to compress and expand air, one or more compressed air storage tanks, a control system, one or more heat exchangers, and, in certain embodiments of the invention, a motor-generator. The reversible air compressor-expander uses mechanical power to compress air (when it is acting as a compressor) and converts the energy stored in compressed air to mechanical power (when it is acting as an expander). In certain embodiments, the compressor-expander comprises one or more stages, each stage consisting of pressure vessel (the “pressure cell”) partially filled with water or other liquid. In some embodiments, the pressure vessel communicates with one or more cylinder devices to exchange air and liquid with the cylinder chamber(s) thereof. Suitable valving allows air to enter and leave the pressure cell and cylinder device, if present, under electronic control.
1. An apparatus comprising:
a chamber in selective fluid communication with a compressed gas storage unit through valving;
a sprayer configured to effect gas-liquid heat exchange with expanding gas within the chamber;
a moveable element rotatable within the chamber to transmit a power of the expanding gas out of the chamber via a mechanical linkage, wherein the mechanical linkage is selectively configured to transmit power into the chamber to cause the moveable element to compress gas within the chamber; and
a generator in communication with the mechanical linkage.
2. The apparatus of claim 1 wherein the mechanical linkage comprises a rotating shaft.
3. The apparatus of claim 2 wherein the mechanical linkage is in communication with a source of shaft torque.
4. The apparatus of claim 3 wherein the source of shaft torque comprises a motor.
5. The apparatus of claim 1 further comprising a gas-liquid separator in fluid communication with the chamber.
6. The apparatus of claim 5 further comprising a liquid reservoir in fluid communication with the gas-liquid separator.
7. The apparatus of claim 6 further comprising a pump configured to flow a separated liquid from the gas-liquid separator.
8. The apparatus of claim 1 wherein the moveable element comprises a rotor.
9. The apparatus of claim 1 wherein the moveable element comprises a vane.
10. An apparatus comprising:
a chamber in selective fluid communication with a compressed gas storage unit through valving;
a sprayer configured to effect gas-liquid heat exchange with expanding gas within the chamber;
a moveable element rotatable within the chamber to transmit a power of the expanding gas out of the chamber via a mechanical linkage; and
a generator in communication with the mechanical linkage, the apparatus further comprising,
a gas-liquid separator in fluid communication with the chamber;
a liquid reservoir in fluid communication with the gas-liquid separator;
a pump configured to flow a separated liquid from the gas-liquid separator; and
a heat exchanger in thermal communication with the separated liquid.
11. The apparatus of claim 10 wherein the mechanical linkage comprises a rotating shaft.
12. The apparatus of claim 10 wherein the moveable element comprises a vane.
13. The apparatus of claim 10 wherein the moveable element comprises a rotor.
14. An apparatus comprising:
a chamber in selective fluid communication with a compressed gas storage unit through valving;
a sprayer configured to effect gas-liquid heat exchange with expanding gas within the chamber;
a moveable element rotatable within the chamber to transmit a power of the expanding gas out of the chamber via a mechanical linkage; and
a generator in communication with the mechanical linkage, the apparatus further comprising a lower pressure stage comprising a second moveable element within a second chamber configured to receive the expanded gas.
15. The apparatus of claim 14 wherein the second moveable element is configured to rotate within the second chamber.
16. The apparatus of claim 14 wherein the second moveable element is configured to reciprocate within the second chamber.
17. The apparatus of claim 14 wherein the second moveable element is in communication with the mechanical linkage.
18. The apparatus of claim 14 wherein the moveable element comprises a vane.
19. The apparatus of claim 14 wherein the moveable element comprises a rotor.
20. The apparatus of claim 14 wherein the mechanical linkage comprises a rotating shaft.