IP Library Granted Patent US 12,624,681
Granted Patent B2
US 12,624,681 · App. 18/867,137 · Granted May 12, 2026

Geothermal power generation systems with pressure exchangers

Inventor: Azam Mihir Thatte (Kensington, CA)
Assignee: Energy Recovery, Inc.
F03G4/02F01K25/103F04F13/00F24T50/00
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Quick Facts
Patent No.
US 12,624,681
App. No.
18/867,137
Granted
May 12, 2026
Kind
B2
Abstract

A system includes a pressure exchanger (PX) configured to receive a first fluid via a first inlet and a second fluid via a second inlet. The PX is to exchange pressure between the first fluid and the second fluid and provide the first fluid at a first outlet and the second fluid at a second outlet. The system further includes a heat exchanger to exchange corresponding thermal energy between the first fluid and the second fluid. The system further includes a turbine configured to receive the second fluid output from the first heat exchanger and convert corresponding energy of the second fluid into rotational kinetic energy.

Claims (61)

1 . A system, comprising:

a pressure exchanger (PX) configured to receive a first fluid at a first pressure via a first inlet of the PX from a geothermal source, receive a second fluid at a second pressure via a second inlet of the PX, and exchange pressure between the first fluid and the second fluid, wherein the first fluid is to exit the PX at a third pressure via a first outlet of the PX, and wherein the second fluid is to exit the PX at a fourth pressure via a second outlet of the PX;

a first flow valve configured to receive the second fluid at the fourth pressure and a third fluid at the fourth pressure, wherein the first flow valve is further configured to combine the third fluid with the second fluid;

a first heat exchanger configured to exchange corresponding thermal energy between the first fluid at approximately the third pressure and the second fluid at approximately the fourth pressure; and

a turbine configured to receive the second fluid output from the first heat exchanger and convert corresponding energy of the second fluid into rotational kinetic energy.

2 . The system of claim 1 , further comprising:

a generator mechanically coupled to the turbine, wherein the generator is configured to generate electricity responsive to the turbine converting corresponding thermal energy of the second fluid into kinetic energy.

3 . The system of claim 1 , further comprising:

a second heat exchanger configured to receive fluid output from the turbine and provide corresponding thermal energy from the fluid output from the turbine to the second fluid input to the first heat exchanger to increase temperature of the second fluid input to the first heat exchanger.

4 . The system of claim 3 , further comprising:

a third heat exchanger configured to receive fluid output from the second heat exchanger, the third heat exchanger configured to provide corresponding thermal energy from the fluid output from the second heat exchanger to a corresponding environment.

5 . The system of claim 1 , further comprising:

a second flow valve configured to provide the second fluid at the second pressure to the PX and to provide the third fluid at the second pressure; and

a compressor or pump configured to receive the third fluid at the second pressure from the second flow valve and increase pressure of the third fluid to the fourth pressure, wherein the first

a flow valve is configured to receive the second fluid at the fourth pressure from the PX and the third fluid at the fourth pressure from the compressor, wherein the first flow valve is further configured to combine the second fluid with the fourth fluid.

6 . The system of claim 1 , further comprising:

a motor coupled to a rotor of the PX, wherein the motor is configured to control a rotational velocity of the rotor.

7 . The system of claim 1 , further comprising:

a booster configured to:

receive the second fluid and increase pressure of the second fluid to the second pressure; and

provide the second fluid at the second pressure to the PX via the second inlet; and

a pump configured to:

receive the first fluid from the geothermal source and increase pressure of the first fluid to the first pressure; and

provide the first fluid at the first pressure to the PX via the first inlet.

8 . The system of claim 1 , further comprising:

a booster configured to:

receive the second fluid from the second outlet of the PX and increase pressure of the second fluid; and

provide the second fluid to be combined with output of a compressor and input to the first heat exchanger.

9 . The system of claim 1 , further comprising:

a first receiver configured to receive the first fluid from the first outlet of the PX, wherein the first receiver forms a first chamber configured to separate the first fluid into a first gas and a first liquid; and

a second receiver configured to receive the second fluid from the second outlet of the PX, wherein the second receiver forms a second chamber configured to separate the second fluid into a second gas and a second liquid.

10 . The system of claim 9 , further comprising:

a first compressor configured to:

receive the first gas from the first receiver and increase pressure of the first gas; and

provide the first gas to be combined with output of a second compressor and input to the first heat exchanger.

11 . The system of claim 1 , further comprising:

a second heat exchanger configured to receive the second fluid output from the turbine and provide corresponding thermal energy from the second fluid to a fourth fluid to increase temperature of the fourth fluid;

a third heat exchanger configured to receive the second fluid output from the second heat exchanger and provide corresponding thermal energy from the second fluid to the fourth fluid to increase temperature of the fourth fluid; and

a compressor configured to receive at least a portion of the second fluid output from the third heat exchanger, increase pressure of the at least a portion of the second fluid, and provide the at least a portion of the second fluid to be combined with the fourth fluid to form the fourth fluid.

12 . The system of claim 1 , wherein the first heat exchanger is configured to:

receive the first fluid output from the PX at the third pressure; or

receive the first fluid from the geothermal source and provide the first fluid to the PX at the first pressure.

13 . The system of claim 1 , wherein the second fluid comprises one or more of carbon dioxide (CO 2 ), a hydrofluorocarbon, or a hydrocarbon.

14 . The system of claim 1 , wherein the first pressure is higher than the second pressure, and wherein the third pressure is lower than the fourth pressure.

15 . A method, comprising:

causing, via a pressure exchanger (PX) pressure to be exchanged between a first fluid received from a geothermal source and a second fluid, wherein the PX is to decrease pressure of the first fluid from a first pressure to a third pressure and increase pressure of the second fluid from a second pressure to a fourth pressure;

causing, via a first flow valve configured to receive the second fluid at the fourth pressure and a third fluid at the fourth pressure, the third fluid to be combined with the second fluid;

causing, via a first heat exchanger, corresponding thermal energy to be provided from the first fluid at approximately the third pressure to the second fluid at approximately the fourth pressure; and

causing, via a turbine, conversion of corresponding energy of the second fluid into rotational kinetic energy.

16 . The method of claim 15 , wherein the PX is to receive the first fluid at the first pressure via the first inlet of the PX from the geothermal source and the PX is to receive the second fluid at the second pressure via a second inlet of the PX, wherein the PX is to exchange pressure between the first fluid and the second fluid, wherein the first fluid is to exit the PX at the third pressure via a first outlet of the PX, and wherein the second fluid is to exit the PX at the fourth pressure via a second outlet of the PX.

17 . The method of claim 15 , further comprising:

causing, via a first receiver forming a first chamber, separation of the first fluid output from the PX into a first gas and a first liquid; and

causing, via a second receiver forming a second chamber, separation of the second fluid output from the PX into a second gas and a second liquid.

18 . A non-transitory computer-readable storage medium comprising instructions that, when executed by a processing device, cause the processing device to perform operations comprising:

causing, via a pressure exchanger (PX) pressure to be exchanged between a first fluid received from a geothermal source and a second fluid, wherein the PX is to decrease pressure of the first fluid from a first pressure to a third pressure and increase pressure of the second fluid from a second pressure to a fourth pressure;

causing, via a first flow valve configured to receive the second fluid at the fourth pressure and a third fluid at the fourth pressure, the third fluid to be combined with the second fluid;

causing, via a first heat exchanger, corresponding thermal energy to be provided from the first fluid at approximately the third pressure to the second fluid at approximately the fourth pressure; and

causing, via a turbine, conversion of corresponding energy of the second fluid into rotational kinetic energy.

19 . The non-transitory computer-readable storage medium of claim 18 , wherein the PX is to receive the first fluid at the first pressure via a first inlet of the PX from the geothermal source and the PX is to receive the second fluid at the second pressure via a second inlet of the PX, wherein the PX is to exchange pressure between the first fluid and the second fluid, wherein the first fluid is to exit the PX at the third pressure via a first outlet of the PX, and wherein the second fluid is to exit the PX at the fourth pressure via a second outlet of the PX.

20 . The non-transitory computer-readable storage medium of claim 18 , wherein the processing device is to perform operation further comprising:

causing, via a second heat exchanger configured to receive fluid output from the turbine, corresponding thermal energy to be provided from the fluid output from the turbine to a corresponding environment.

Assignments (2)
SECURITY INTEREST Recorded Jan 21, 2026
From: ENERGY RECOVERY, INC.
To: JPMORGAN CHASE BANK, N.A.
Reel/Frame 073535/0966 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Nov 19, 2024
From: THATTE, AZAM MIHIR
To: ENERGY RECOVERY, INC.
Reel/Frame 069322/0125 →
Continuity (2)
Provisional Application 63345789 · May 25, 2022
Related Publication 20250215861A1 · Jul 3, 2025
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