Fluid-flow control in energy storage and recovery systems

• US 8,578,708 B2
• Filed: 11/30/2011
• Issued: 11/12/2013
• Est. Priority Date: 11/30/2010
• Status: Expired due to Fees

• Current Assignee: SustainX, Inc. (General Compression, Inc.)
• Original Assignee: SustainX, Inc. (General Compression, Inc.)
• Inventors: Bollinger, Benjamin R., Doyle, Lee, McBride, Troy O., Shang, Andrew, Scott, Michael Neil
• Primary Examiner(s): Lopez, F. Daniel
• Application Number:
  US13/307,163
• Publication Number:
  US 20120085086A1
• Time in Patent Office: 713 Days
• Field of Search: 603/98, 604/09, 912/73, 912/75, 912/87
• US Class Current: 60/398
• CPC Class Codes: F15B 1/00 Installations or systems with accumulators; Supply reservoir or sump assemblies
• CPC Class Codes: H02J 15/006 in the form of pneumatic energy, e.g. compressed air energy storage [CAES] accumulators for supplying fluid under pressure F15B1/04
• CPC Class Codes: Y02E 60/16 Mechanical energy storage, e.g. flywheels or pressurised fluids
• CPC Class Codes: Y02P 80/10 Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier

Abstract

In various embodiments, compressed-gas energy storage and recovery systems feature one or more valves, which may be disposed within end caps of cylinder assemblies in which gas is expanded and/or compressed, for admitting fluid to and/or exhausting fluid from the cylinder assembly.

Claims

1. An energy storage and recovery system comprising:

a cylinder assembly (i) for, therewithin, at least one of the compression of gas to store energy or the expansion of gas to recover energy and (ii) having an interior compartment and an end cap disposed at an end of the cylinder assembly;

integrated within the end cap, (i) a first valve for admitting fluid into the interior compartment of the cylinder assembly prior to expansion and exhausting fluid from the interior compartment of the cylinder assembly after compression, and (ii) a second valve for exhausting fluid from the interior compartment of the cylinder assembly after expansion and admitting fluid into the interior compartment of the cylinder assembly prior to compression, each of the first and second valves comprising a gated port and an outside port, the first and second valves controlling fluid communication with the interior compartment via respective separate fluid paths;

a first actuation mechanism for actuating the first valve;

a second actuation mechanism for actuating the second valve; and

a control system for controlling the first and second actuation mechanisms based on at least one of a pressure inside the interior compartment of the cylinder assembly, a position of the gated port of the first valve, or a position of the gated port of the second valve, the control system reducing a pressure differential through at least one of the first or second valves during fluid flow therethrough, thereby increasing efficiency of the energy storage and recovery,

wherein;

the second actuation mechanism is configured for (i) applying a first actuation force against a first pressure differential between a pressure in the interior compartment and a pressure within the second valve between the gated port and the outside port and (ii) applying a second actuation force greater than the first actuation force against a second pressure differential, greater than the first pressure differential, between the pressure in the interior compartment and the pressure within the second valve between the gated port and the outside port,

the cylinder assembly is configured to operate at the first pressure differential during the at least one of compression or expansion of gas,

the second actuation mechanism is configured to apply the second actuation force only when the first actuation force is insufficient to open the second valve, and

the second actuation mechanism comprises a hydraulic mechanism selectively connectable to (i) a first source of fluid at a pressure sufficient to provide an actuation force greater than the first actuation force and less than the second actuation force and (ii) a second source of fluid at a pressure greater than the pressure of the first source of fluid and sufficient to provide an actuation force greater than the second actuation force.

2. The system of claim 1, wherein the first valve is a high-side valve and the second valve is a low-side valve.

3. The system of claim 1, wherein the outside port of the first valve is in selective communication with a compressed-gas reservoir.

4. The system of claim 1, wherein the outside port of the first valve is in selective communication with a second cylinder assembly configured for at least one of expansion or compression of gas at a higher range of pressures than a pressure range of the expansion or compression within the interior compartment of the cylinder assembly.

5. The system of claim 1, wherein the outside port of the second valve is in selective communication with a vent to atmosphere.

6. The system of claim 1, wherein the outside port of the second valve is in selective communication with a second cylinder assembly configured for at least one of expansion or compression of gas at a lower range of pressures than a pressure range of the expansion or compression within the interior compartment of the cylinder assembly.

7. The system of claim 1, wherein each of the first and second actuation mechanisms is at least one of hydraulic, electrical, or mechanical.

8. The system of claim 1, wherein (i) each of the first and second valves comprises a disc that selectively closes the gated port, (ii) the gated port of the first valve is disposed between the disc of the first valve and the interior compartment, and (iii) the disc of the second valve is disposed between the gated port of the second valve and the interior compartment.

9. The system of claim 1, wherein the interior compartment is a pneumatic chamber, and further comprising a movable boundary mechanism disposed within the cylinder assembly and separating the interior compartment from a second interior compartment.

10. The system of claim 1, further comprising, disposed within the end cap, (i) a first channel forming at least a portion of the fluid path controlled by the first valve and (ii) a second channel, separate from the first channel, forming at least a portion of the fluid path controlled by the second valve.

11. The system of claim 1, further comprising a mechanism for introducing heat-exchange fluid into the interior compartment.

12. The system of claim 11, wherein the mechanism comprises at least one of a spray head or a spray rod.

13. The system of claim 11, wherein the first valve and the second valve are both configured for exhausting two-phase flow of gas and heat-exchange fluid from the interior compartment.

14. The system of claim 1, wherein each of the first and second valves is configured to check open, enabling fluid communication with the interior compartment of the cylinder assembly, in the absence of actuation force applied by its actuation mechanism.

15. The system of claim 1, wherein the second valve is configured to check open and enable fluid flow therethrough at a pressure differential less than approximately 20% of a pressure within the cylinder assembly during a hydrolock event, thereby preventing hydrolock damage to the cylinder assembly.

16. The system of claim 1, wherein the control system actuates open the second valve at a pressure (i) outside the interior compartment, (ii) acting on the second valve, and (iii) insufficient to check open the second valve, thereby reducing the pressure differential during fluid flow through the second valve.

17. The system of claim 1, wherein the control system actuates open the first valve at a pressure (i) within the interior compartment, (ii) acting on the first valve, and (iii) insufficient to check open the first valve, thereby reducing the pressure differential during fluid flow through the first valve.

18. The system of claim 1, further comprising, connected to the cylinder assembly, an intermittent renewable energy source of wind or solar energy, wherein (i) energy stored during compression of the gas originates from the intermittent renewable energy source, and (ii) energy is recovered via expansion of the gas when the intermittent renewable energy source is nonfunctional.