Geopressure and geothermal power systems

Abstract

A geothermal power system includes a turbocharger fluidically coupled to a heat exchanger. A first fluid enters the turbocharger at a first inlet, and flows in a first fluid path to a first outlet. The first fluid flows from the first outlet to the heat exchanger. The first fluid heats a second fluid at the heat exchanger. The first fluid flows from the heat exchanger to a second inlet of the turbocharger. The first fluid enters the turbocharger at the second inlet, and flows in a second fluid path to a second outlet. A pressure of the first fluid reduces as the first fluid transits through the turbocharger along the first fluid path. A pressure of the first fluid increases as the first fluid transits through the turbocharger along the second fluid path.

Description

PATENTAttorney Docket No.: SGEO / 0020PCGEOPRESSURE AND GEOTHERMAL POWER SYSTEMSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is an International Patent Application under the Patent Cooperation Treaty, and claims priority to and the benefit of U.S. Provisional Patent Application Serial No. 63 / 735,180 filed December 17, 2024 and titled Geopressure and Geothermal Power Systems, the disclosure of which is incorporated herein in its entirety by this reference.BACKGROUNDField

[0002] Embodiments of the present disclosure generally relate to geothermal power systems and processes, and particularly to the recovery of geothermal heat energy and pressure energy to perform useful work, such as generating electricity.Description of the Related Art

[0003] Geothermal energy is a type of renewable energy generated within the earth. A geothermal fluid (such as water, steam, brine, or hydrocarbons) is heated in a subterranean geological formation by the earth’s natural internal temperature. The heated geothermal fluid is produced to the earth’s surface. The enthalpy of the geothermal fluid includes a heat energy component and a pressure-volume energy component. Typically, the heat energy component is greater than the pressurevolume energy component. At the earth’s surface, the heat energy component is used to perform useful work, such as heating buildings or generating electricity in a geothermal power system. However, the pressure-volume energy component is usually wasted, such as by venting. After performing useful work, the geothermal fluid is reinjected into the subterranean formation, reheated by the subterranean formation, then produced again to the earth’s surface to perform useful work.

[0004] Some geothermal power systems generate electricity by using the geothermal fluid to drive a steam turbine. However, where the produced geothermal fluid is at or below about 180 degrees C, geothermal power systems typically incorporate a binary cycle power plant to generate electricity. A heat exchanger of thePATENTAttorney Docket No.: SGEO / 0020PC binary cycle power plant transfers heat, but not pressure, from the geothermal fluid to a working fluid of the binary cycle power plant.

[0005] In an example, operation of the binary cycle power plant is based on the Brayton Cycle, in which the heated working fluid passes through a turbine, which drives a generator. In another example, operation of the binary cycle power plant is based on the Organic Rankine Cycle, in which the heated working fluid passes through an expander, which drives a generator. Typically, binary cycle power plants utilize only the heat energy component of the enthalpy of the geothermal fluid. The pressurevolume energy component is wasted, such as by venting.

[0006] The efficiency of a geothermal power system depends on the amount of energy (in the form of heat energy and pressure-volume energy) that can be transferred from the subterranean geological formation to the geothermal fluid, and depends on the proportion of that energy that is converted into useful work. Typically, the efficiency of converting geothermal energy (in the form of heat energy plus pressure-volume energy) into electricity is less than 15 percent.

[0007] Thus, there is a need for improved systems and processes that facilitate the conversion of geothermal energy into electricity.SUMMARY

[0008] The present disclosure generally relates to geothermal power systems and processes, and particularly to the recovery of geothermal heat energy and pressure energy to perform useful work, such as generating electricity. In one implementation, a method of operating a geothermal power system includes flowing a first fluid into a first inlet of a first turbocharger, and flowing the first fluid from a first outlet of the first turbocharger to a heat exchanger. The method further includes flowing the first fluid from the heat exchanger to a second inlet of the first turbocharger, and discharging the first fluid from a second outlet of the first turbocharger.

[0009] In another implementation, a method of operating a geothermal power system includes flowing a first fluid into a first inlet of a turbocharger, and reducing a pressure of the first fluid in the turbocharger as the first fluid transits from the first inletPATENTAttorney Docket No.: SGEO / 0020PC of the turbocharger to a first outlet of the turbocharger. The method further includes increasing a pressure of a second fluid in the turbocharger as the second fluid transits from a second inlet of the turbocharger to a second outlet of the turbocharger. The second fluid has a first temperature at the second outlet. The method further includes flowing the second fluid through a turbine coupled to a generator. The second fluid enters the turbine at a second temperature substantially equal to the first temperature. The method further includes generating electricity using the generator. The method further includes flowing the second fluid from the turbine to the second inlet of the turbocharger. The second fluid exits the turbine at a third temperature, and enters the second inlet of the turbocharger at a fourth temperature substantially equal to the third temperature.

[0010] In another implementation, a geothermal power system includes a heat exchanger fluidically coupled to a first turbocharger. The first turbocharger is configured such that a first fluid enters the first turbocharger at a first inlet, and transits through the first turbocharger in a first fluid path from the first inlet to a first outlet. The heat exchanger receives the first fluid from the first outlet of the first turbocharger, and the first turbocharger receives the first fluid from the heat exchanger at a second inlet of the turbocharger. The first turbocharger is further configured such that the first fluid transits through the first turbocharger in a second fluid path from the second inlet to a second outlet. The second fluid path is separate from the first fluid path.

[0011] In another implementation, a method of operating a geothermal power system includes flowing a first fluid into a first inlet of a turbocharger, and flowing the first fluid from a first outlet of the turbocharger to a heat exchanger. The method further includes flowing the first fluid from the heat exchanger to a second inlet of the turbocharger, flowing the first fluid from a second outlet of the turbocharger to a turbine coupled to a generator, and generating electricity using the generator.

[0012] In another implementation, a method of operating a geothermal power system includes simultaneously flowing a first fluid and a second fluid such that the first fluid passes through a turbocharger and then through a heat exchanger, and the second fluid passes through the heat exchanger and then through the turbocharger. The method further includes transferring heat from the first fluid to the second fluid atPATENTAttorney Docket No.: SGEO / 0020PC the heat exchanger, and reducing a pressure of the first fluid at the turbocharger by increasing a pressure of the second fluid at the turbocharger. The method further includes flowing the second fluid from the turbocharger to an expander coupled to a generator, operating the expander to reduce the pressure and a temperature of the second fluid, and generating electricity using the generator.

[0013] In another implementation, a geothermal power system includes a heat exchanger flu idical ly coupled to a turbocharger. The turbocharger is configured such that a first fluid enters the turbocharger at a first inlet, and transits through the turbocharger in a first fluid path from the first inlet to a first outlet. The heat exchanger receives the first fluid from the first outlet of the turbocharger, and the turbocharger receives the first fluid from the heat exchanger at a second inlet of the turbocharger. The turbocharger is further configured such that the first fluid transits through the turbocharger in a second fluid path from the second inlet to a second outlet. The second fluid path is separate from the first fluid path. The geothermal power system further includes a turbine fluidically coupled to the second outlet of the turbocharger, and a first generator coupled to the turbine.

[0014] In another implementation, a method of operating a geothermal power system includes producing a first fluid from a geothermal reservoir, and introducing the first fluid into a first turbocharger. The method includes reducing a pressure of the first fluid in the first turbocharger. The method includes conveying the first fluid from the first turbocharger to a heat exchanger, and increasing a temperature of a second fluid at the heat exchanger using the first fluid.

[0015] In another implementation, a geothermal power system includes a first turbocharger configured to receive a first fluid produced from a geothermal reservoir. The geothermal power system further includes a heat exchanger fluidically coupled to the first turbocharger, and configured to receive the first fluid from the first turbocharger. The geothermal power system further includes a pump fluidically coupled to the heat exchanger, and configured to receive the first fluid from the heat exchanger.PATENTAttorney Docket No.: SGEO / 0020PC

[0016] In another implementation, a geothermal power system includes a heat exchanger configured to receive a first fluid produced from a geothermal reservoir. The geothermal power system further includes a first turbocharger flu idical ly coupled to the heat exchanger, and configured to receive the first fluid from the heat exchanger. The geothermal power system further includes a pump fluidically coupled to the first turbocharger, and configured to receive the first fluid from the first turbocharger.BRIEF DESCRIPTION OF THE DRAWINGS

[0017] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of the scope of the disclosure, as the disclosure may admit to other equally effective embodiments.

[0018] Figure 1A schematically illustrates a geothermal power system.

[0019] Figure 1 B schematically illustrates a manifold assembly that may be incorporated into the geothermal power system of Figure 1A.

[0020] Figure 1 C schematically illustrates process flows for a single well that may be used with the geothermal power system of Figure 1 A.

[0021] Figure 1 D schematically illustrates a flowline assembly that may be used with the geothermal power system of Figure 1 A.

[0022] Figure 2 schematically illustrates a geothermal power system.

[0023] Figure 3 schematically illustrates a geothermal power system.

[0024] Figure 4 schematically illustrates a geothermal power system.

[0025] Figure 5 schematically illustrates a geothermal power system.

[0026] Figure 6 schematically illustrates a geothermal power system.PATENTAttorney Docket No.: SGEO / 0020PC

[0027] Figure 7 schematically illustrates a geothermal power system.

[0028] Figures 8A to 8D schematically illustrate embodiments of turbochargers that may be incorporated into any of the geothermal power systems disclosed herein.

[0029] Figure 9 is a flow diagram of a method of operating a geothermal power system.

[0030] Figure 10 is a flow diagram of a method of operating a geothermal power system.

[0031] Figure 11 is a flow diagram of a method of operating a geothermal power system.

[0032] Figure 12 is a flow diagram of a method of operating a geothermal power system.

[0033] Figure 13 is a flow diagram of a method of operating a geothermal power system.

[0034] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.DETAILED DESCRIPTION

[0035] The present disclosure concerns geothermal power systems and processes, and particularly to the recovery of geothermal energy to perform useful work, such as generating electricity.

[0036] Figure 1A schematically illustrates a geothermal power system 100. The geothermal power system 100 includes a binary cycle power plant 10. In some embodiments, operation of the binary cycle power plant 10 is based on the Brayton Cycle. In some embodiments, operation of the binary cycle power plant 10 is based on the Rankine Cycle. In some embodiments, operation of the binary cycle power plant 10 is based on the Organic Rankine Cycle.PATENTAttorney Docket No.: SGEO / 0020PC

[0037] The binary cycle power plant 10 utilizes a working fluid (represented by arrows 12), such as water, steam, brine, a refrigerant, a supercritical fluid, carbon dioxide, ammonia, an organic compound (e.g., a hydrocarbon, a fluorocarbon, etc.), or any combination thereof. The working fluid 12 flows from a condenser 20 to a pressure booster 22, such as a pump (e.g. a single phase pump, a multi-phase pump, a centrifugal pump, or a positive displacement pump), a compressor, or the like. The pressure booster 22 increases the pressure of the working fluid 12, and moves the working fluid 12 through a recuperator 24 to a heat exchanger 26, where the working fluid 12 is heated. Exemplary types of heat exchanger 26 include concurrent flow heat exchanger, counter-flow heat exchanger, shell and tube heat exchanger, parallel flow plate heat exchanger, and the like.

[0038] The heated working fluid 12 then flows to an expander 30, such as a turbine, a turbo-expander, or the like. The working fluid 12 drives the expander 30 to rotate a shaft 32. The shaft 32 is coupled to a generator 36. In an example, the shaft 32 is coupled to the generator 36 via a gearbox. The shaft 32 drives the generator 36 to produce electricity. The working fluid 12 loses pressure in driving the expander 30, and a temperature of the working fluid 12 drops. The working fluid 12 exits the expander 30, and passes through the recuperator 24, and back to the condenser 20.

[0039] In some embodiments, the pressure booster 22 and the expander 30 are coupled to a common shaft, such as shaft 32. In some embodiments, the pressure booster 22, the expander 30, and the generator 36 are coupled to a common shaft, such as shaft 32.

[0040] The geothermal power system 100 utilizes a geothermal fluid (represented by arrows 102), such as water, steam, brine, a refrigerant, a supercritical fluid, carbon dioxide, ammonia, an organic compound (e.g., a hydrocarbon, a fluorocarbon, etc.), or any combination thereof. In some embodiments, the working fluid 12 in the binary cycle power plant 10 is segregated from the geothermal fluid 102. In some embodiments, the working fluid 12 may include at least a portion of the geothermal fluid 102. In some embodiments, the geothermal fluid 102 may include at least a portion of the working fluid 12.PATENTAttorney Docket No.: SGEO / 0020PC

[0041] The geothermal fluid 102 is heated, or is maintained at an elevated temperature, by a subterranean formation 42 below the earth’s surface 40. In an example, the temperature of the geothermal fluid 102 is at or about 150 degrees C or higher, such as 175 degrees C or higher, 200 degrees C or higher, 250 degrees C or higher, or 300 degrees C or higher. The geothermal fluid 102 is maintained at an elevated pressure in the subterranean formation 42. In an example, the pressure of the geothermal fluid 102 in the subterranean formation 42 is at or about 3 MPa or higher, such as 5 MPa or higher, 10 MPa or higher, 20 MPa or higher, 30 MPa or higher, 40 MPa or higher, or 50 MPa or higher. In some embodiments, the geothermal fluid 102 is geopressured. In an example, the geothermal fluid 102 may be a geopressured-geothermal fluid.

[0042] The geothermal fluid 102 flows from the subterranean formation 42 into a first well 44. In some embodiments, the geothermal fluid 102 flows from the subterranean formation 42 into the first well 44 via one or more fractures 62 in the subterranean formation 42 at the first well 44. In some embodiments, the temperature of the geothermal fluid 102 at a wellhead 45 of the first well 44 is at or near the temperature of the geothermal fluid 102 in the subterranean formation 42.

[0043] The geothermal fluid 102 flows from the first well 44 to a turbocharger 110. Any of turbocharger 800A, 800B, 800C, or 800D (all described below) may be used as turbocharger 110. In some embodiments, the geothermal power system 100 includes a plurality of turbochargers 110, such as in a parallel hookup configuration.

[0044] The geothermal fluid 102 flows into the turbocharger 110 at a first inlet 112, and exits the turbocharger 110 at a first outlet 114. The pressure of the geothermal fluid 102 is reduced as the geothermal fluid 102 transits through the turbocharger 110 from the first inlet 112 to the first outlet 114 along a first fluid path 116. In an example, the pressure of the geothermal fluid 102 at the first outlet 114 is at or about 20 MPa or less, such as 15 MPa or less, 10 MPa or less, 5 MPa or less, 3 MPa or less, 1 MPa or less, 0.5 MPa or less, or 0.2 MPa or less. The temperature of the geothermal fluid 102 at the first inlet 112 is at or near the temperature of the geothermal fluid 102 at the wellhead 45 of the first well 44. The temperature of the geothermal fluid 102 atPATENTAttorney Docket No.: SGEO / 0020PC the first outlet 114 is at or near the temperature of the geothermal fluid 102 at the first inlet 112.

[0045] The geothermal fluid 102 flows from the first outlet 114 of the turbocharger 110 to the heat exchanger 26. In some embodiments, the temperature of the geothermal fluid 102 entering the heat exchanger 26 is similar to the temperature of the geothermal fluid 102 at the first well 44. In an example, the geothermal fluid 102 is at or about 150 degrees C or higher, such as 175 degrees C or higher, 200 degrees C or higher, 250 degrees C or higher, or 300 degrees C or higher when entering the heat exchanger 26. Heat is transferred from the geothermal fluid 102 to the working fluid 12 as the geothermal fluid 102 flows through the heat exchanger 26. The temperature of the geothermal fluid 102 is lowered to a reduced level as the geothermal fluid 102 flows through the heat exchanger 26. In an example, the temperature of the geothermal fluid 102 upon exiting the heat exchanger 26 is at or about 100 degrees C or less, such as 90 degrees C or less, 80 degrees C or less, 70 degrees C or less, 60 degrees C or less, or 50 degrees C or less.

[0046] In some embodiments, the geothermal fluid 102 flows from the heat exchanger 26 to one or more pumps 130. Exemplary pumps 130 include single phase pumps, multi-phase pumps, centrifugal pumps, positive displacement pumps, or the like. In some embodiments, the geothermal fluid 102 flows from the heat exchanger 26 to an intermediate reservoir (such as a pond, a tank, or a subterranean formation different from subterranean formation 42), before flowing to the one or more pumps 130. In some embodiments, the intermediate reservoir is omitted. In some embodiments, the one or more pumps 130 are omitted.

[0047] The geothermal fluid 102 flows from the heat exchanger 26 or the intermediate reservoir (if present) via the one or more pumps 130 (if present) to a second inlet 122 of the turbocharger 110. In some embodiments, the intermediate reservoir functions as a buffer to facilitate controlling the flow rate of the geothermal fluid 102 from the heat exchanger 26 to the second inlet 122 of the turbocharger 110. In an example, the flow rate of the geothermal fluid 102 from the heat exchanger 26 to the second inlet 122 of the turbocharger 110 is controlled to smooth out spikes and dips. In another example, the flow rate of the geothermal fluid 102 from the heatPATENTAttorney Docket No.: SGEO / 0020PC exchanger 26 to the second inlet 122 of the turbocharger 110 is controlled to correspond to the flow rate of the geothermal fluid 102 from the first outlet 114 of the turbocharger 110 to the heat exchanger 26.

[0048] The geothermal fluid 102 flows into the turbocharger 110 at the second inlet 122, and exits the turbocharger 110 at a second outlet 124. The turbocharger 110 utilizes the pressure of the relatively hotter geothermal fluid 102 at the first inlet 112 to increase the pressure of the relatively colder geothermal fluid 102 that enters the turbocharger 110 at the second inlet 122. The pressure of the geothermal fluid 102 is increased as the geothermal fluid 102 transits through the turbocharger 110 from the second inlet 122 to the second outlet 124 along a second fluid path 126. The second fluid path 126 is separate from the first fluid path 116. In an example, the pressure of the geothermal fluid 102 at the second outlet 124 is at or about 3 MPa or higher, such as 5 MPa or higher, 10 MPa or higher, 20 MPa or higher, 30 MPa or higher, 40 MPa or higher, or 50 MPa or higher. In some embodiments, the pressure of the geothermal fluid 102 at the second outlet 124 is less than the pressure of the geothermal fluid 102 at the first inlet 112. In some embodiments, the pressure of the geothermal fluid 102 at the second outlet 124 is substantially equal to the pressure of the geothermal fluid 102 at the first inlet 112. In an example, the pressure of the geothermal fluid 102 at the second outlet 124 is 95% to 100% of the pressure of the geothermal fluid 102 at the first inlet 112. The temperature of the geothermal fluid 102 remains at or near the reduced level as the geothermal fluid 102 transits through the turbocharger 110 from the second inlet 122 to the second outlet 124 along the second fluid path 126.

[0049] The circuit of routing the geothermal fluid 102 through the turbocharger 110, then through the heat exchanger 26, then back through the turbocharger 110 provides several benefits. For example, the heat exchanger 26 may be designed to operate at pressures that are lower than the pressure of the geothermal fluid 102 at the wellhead 45, which avoids the expense and inefficiencies of so-called “high pressure heat exchangers” configured to operate at pressures higher than conventional heat exchangers. Additionally, the pressure of the geothermal fluid 102 itself exiting the first well 44 is used to boost the pressure of the geothermal fluid 102 exiting the heat exchanger 26, which avoids the expense and inefficiencies of pumps that operate atPATENTAttorney Docket No.: SGEO / 0020PC pressure ratios (outlet pressure divided by inlet pressure) of ten or more. The pressure of the geothermal fluid 102 at the wellhead 45 is usefully employed, rather than being wasted.

[0050] The geothermal fluid 102 flows from the second outlet 124 of the turbocharger 110 to one or more turbines 140. In some embodiments, the one or more turbines 140 are Pelton Turbines. In some embodiments, the one or more turbines 140 are other types of turbine, such as Francis Turbines or Kaplan Turbines. In some embodiments, the one or more turbines 140 are located at the earth’s surface 40. In some embodiments, the one or more turbines 140 include a plurality of turbines 140 arranged in a series configuration such that the geothermal fluid 102 flows to a first turbine 140 and then to a second turbine 140. In some embodiments, the one or more turbines 140 include a plurality of turbines 140 arranged in a parallel configuration. In an example, a first portion of the geothermal fluid 102 flows to a first turbine 140, and a different second portion of the geothermal fluid 102 flows simultaneously to a second turbine 140. In another example, one of the first or second turbines 140 is offline (such as for maintenance), and the geothermal fluid 102 flows to the other of the first or second turbines 140.

[0051] Each of the one or more turbines 140 is coupled to a shaft 146. Each shaft 146 is coupled to a corresponding generator 148. In an example, each shaft 146 is coupled to the corresponding generator 148 via a gearbox. Each shaft 146 drives the corresponding generator 148 to produce electricity.

[0052] Each of the one or more turbines 140 has an inlet 142 and an outlet 144. The geothermal fluid 102 flows from the inlet 142, and through the turbine 140 to the outlet 144. A pressure of the geothermal fluid 102 at the inlet 142 of each of the one or more turbines 140 is greater than the pressure of the geothermal fluid 102 at the outlet 144 of each of the one or more turbines 140. The geothermal fluid 102 experiences a drop in pressure from the inlet 142 to the outlet 144 of each turbine 140 as the geothermal fluid 102 drives each turbine 140 to rotate the corresponding shaft 146, and drive the corresponding generator 148 to produce electricity. In an example, the pressure of the geothermal fluid 102 at the outlet 144 of each turbine 140 is at orPATENTAttorney Docket No.: SGEO / 0020PC about 1 MPa or less, such as 0.5 MPa or less, 0.4 MPa or less, 0.3 MPa or less, or 0.2 MPa or less.

[0053] The geothermal fluid 102 flows from the outlet 144 of each of the one or more turbines 140 to one or more pumps 134. Exemplary pumps 134 include single phase pumps, multi-phase pumps, centrifugal pumps, positive displacement pumps, or the like. The one or more pumps 134 increase a pressure of the geothermal fluid 102, and inject the geothermal fluid 102 into the second well 46. The geothermal fluid 102 flows through the second well 46, and enters the one or more fractures 64 in the subterranean formation 42.

[0054] In some embodiments, the geothermal fluid 102 flows from the outlet 144 of each of the one or more turbines 140 to a reservoir 132 (such as a pond, a tank, or a subterranean formation different from subterranean formation 42), before flowing to the one or more pumps 134. In some embodiments, the reservoir 132 provides for temporary storage of the geothermal fluid 102 prior to injecting the geothermal fluid 102 into the second well 46. In an example, the geothermal fluid 102 is utilized in the geothermal power system 100 to produce electricity and is stored in reservoir 132 during a period of relatively high demand for electricity, then is injected into the second well 46 during a subsequent period of relatively low demand for electricity. In some embodiments, the reservoir 132 is omitted.

[0055] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 45 of the first well 44 is maintained at a magnitude such that the one or more fractures 62 remain open while flowing the geothermal fluid 102 to the turbocharger 110. In an example, the flow of the geothermal fluid 102 out of the first well 44 is choked by valve 52. In another example, the turbocharger 110 is operated such that a back-pressure is exerted on the geothermal fluid 102 at the wellhead 45 of the first well 44.

[0056] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 is maintained at a magnitude such that the one or more fractures 64 remain open. In an example, the one or more pumps 134 arePATENTAttorney Docket No.: SGEO / 0020PC operated to maintain the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 at a magnitude such that the one or more fractures 64 remain open.

[0057] In some embodiments, the one or more fractures 62 intersect with the one or more fractures 64. In some embodiments, the one or more fractures 62 are contiguous with the one or more fractures 64. In some embodiments, the geothermal fluid 102 flows within the subterranean formation 42 from the second well 46 to the first well 44, and is produced again from the first well 44.

[0058] As illustrated, in some embodiments, the geothermal fluid 102 does not flow within the subterranean formation 42 from the second well 46 to the first well 44. In an example, the one or more fractures 62 do not intersect with the one or more fractures 64. In another example, the one or more fractures 62 are not contiguous with the one or more fractures 64. In such embodiments, the geothermal power system 100 is reconfigured to flow the geothermal fluid 102 from the second well 46 to the turbocharger 110, and to flow the returning geothermal fluid 102 from the one or more pumps 134 to the first well 44. In an example, the geothermal power system 100 includes a manifold assembly, such as described below.

[0059] Figure 1 B schematically illustrates an example manifold assembly 150 that facilitates reconfiguring the geothermal power system 100 to flow the geothermal fluid 102 from the second well 46 to the turbocharger 110, and to flow the returning geothermal fluid 102 from the one or more pumps 134 to the first well 44. In some embodiments, geothermal power system 100 incorporates the manifold assembly 150.

[0060] The manifold assembly 150 includes a production manifold 160 and an injection manifold 170. Line 162 conveys the geothermal fluid 102 from the production manifold 160 to the turbocharger 110. Line 172 conveys the geothermal fluid 102 from the one or more pumps 134 to the injection manifold 170. Line 164 conveys the geothermal fluid 102 from the first well 44 to the production manifold 160. Line 174 conveys the geothermal fluid 102 from the injection manifold 170 to the first well 44. When geothermal fluid 102 is flowing from the first well 44 to the production manifold 160, valve 182 in line 164 is open, and valve 184 in line 174 is closed. WhenPATENTAttorney Docket No.: SGEO / 0020PC geothermal fluid 102 is flowing from the injection manifold 170 to the first well 44, valve 184 in line 174 is open, and valve 182 in line 164 is closed.

[0061] Line 166 conveys the geothermal fluid 102 from the second well 46 to the production manifold 160. Line 176 conveys the geothermal fluid 102 from the injection manifold 170 to the second well 46. When geothermal fluid 102 is flowing from the second well 46 to the production manifold 160, valve 186 in line 166 is open, and valve 188 in line 176 is closed. When geothermal fluid 102 is flowing from the injection manifold 170 to the second well 46, valve 188 in line 176 is open, and valve 186 in line 166 is closed.

[0062] In some embodiments, reconfiguring the geothermal power system 100 is prompted by a trigger condition. In an example, the trigger condition includes the flow of geothermal fluid 102 from the first well 44 to the turbocharger 110 diminishing to or beyond a threshold level. In another example, the trigger condition includes the pressure of geothermal fluid 102 at the wellhead 45 of the first well 44 diminishing to or beyond a threshold level. In another example, the trigger condition includes the flow of geothermal fluid 102 into the second well 46 diminishing to or beyond a threshold level. In another example, the trigger condition includes the pressure of geothermal fluid 102 at the wellhead 47 of the second well 46 rising to or beyond a threshold level.

[0063] When reconfiguring the geothermal power system 100 to flow the geothermal fluid 102 from the second well 46 to the geothermal power system 100, the first well 44 is closed-in, such as by closing the valve 52. In some embodiments, the second well 46 is closed-in, such as by closing valve 54. The manifold assembly 150 is operated such that valve 182 is closed, valve 184 is opened, valve 186 is opened, and valve 188 is closed. Valve 52 is opened to allow geothermal fluid 102 to be injected into the first well 44. If the second well 46 is closed-in, valve 54 is opened to allow geothermal fluid 102 to be produced from the second well 46. The geothermal fluid 102 flows from the subterranean formation 42 via the second well 46 to the turbocharger 110, as described above. The returning geothermal fluid 102 flows into the subterranean formation 42 via the first well 44, as described above.PATENTAttorney Docket No.: SGEO / 0020PC

[0064] In some embodiments, more than two wells are coupled to the production manifold 160 and to the injection manifold 170. In an example, production of geothermal fluid 102 is started from a third well while the second well 46 remains closed-in. The geothermal fluid 102 flows to the geothermal power system 100 as described above. The geothermal fluid 102 may then be injected into the first well 44 or into a fourth well.

[0065] Figure 1 C schematically illustrates an embodiment in which well 70 functions as the first well 44 and the second well 46. In some embodiments, a single well (configured as well 70 that functions as the first well 44 and the second well 46) is fluidically coupled to the turbocharger 110 and to the one or more pumps 134. In some embodiments, the turbocharger 110 and the one or more pumps 134 are coupled to only a single well, and that well is configured as well 70. In some embodiments, the turbocharger 110 and the one or more pumps 134 are coupled to a plurality of wells, each of which is configured as well 70 by being configured to function as the first well 44 and the second well 46. In an example, each well 70 is coupled to the production manifold 160 and to the injection manifold 170.

[0066] The well 70 includes a production zone 72 and an injection zone 74. Fluids in the subterranean formation 42 flow into the well 70 at the production zone 72. Fluids flow from the well 70 into the subterranean formation 42 at the injection zone 74. A fracture network 60 in the subterranean formation 42 is fluidically coupled to the production zone 72 and to the injection zone 74.

[0067] In some embodiments, the well 70 is operated such that the fracture network 60 remains open while the geothermal fluid 102 is produced from the subterranean formation 42 into the production zone 72. In some embodiments, the well 70 is operated such that the fracture network 60 remains open while the geothermal fluid 102 is injected into the subterranean formation 42 at the injection zone 74. In an example, a pressure of the geothermal fluid 102 within the fracture network 60 is maintained at a magnitude that is greater than a closure pressure of one or more fractures of the fracture network 60. In another example, a pressure of the geothermal fluid 102 within the fracture network 60 is maintained at a magnitude that is greater than an opening pressure of one or more fractures of the fracture network 60. InPATENTAttorney Docket No.: SGEO / 0020PC another example, a pressure of the geothermal fluid 102 within the fracture network 60 is maintained at a magnitude that is between the opening pressure and the closure pressure of one or more fractures of the fracture network 60. In another example, a pressure of the geothermal fluid 102 within the fracture network 60 is maintained at a magnitude that is greater than a reopening pressure of one or more fractures of the fracture network 60. In another example, a pressure of the geothermal fluid 102 within the fracture network 60 is maintained at a magnitude that is between the reopening pressure and the closure pressure of one or more fractures of the fracture network 60.

[0068] In some embodiments, operation of the well 70 such that the fracture network 60 remains open is performed by regulating a pressure within the well 70 by a control valve, such as valve 52 (Fig. 1A), a choke, or the like. In some embodiments, operation of the well 70 such that fracture network 60 remains open is performed by regulating a pressure within the well 70 by controlling the operation of the turbocharger 110. In an example, the pressure drop experienced by the geothermal fluid 102 flowing through the turbocharger 110 creates a back-pressure on the geothermal fluid 102 exiting the well 70. In some embodiments, operation of a control valve is omitted when regulating a pressure within the well 70 by controlling the operation of the turbocharger 110. In some embodiments, operation of the well 70 such that the fracture network 60 remains open is performed by regulating the one or more pumps 134.

[0069] The well 70 includes a tubing string 76 installed inside a casing string 78. A packer 82 seals an annulus 80 between the tubing string 76 and the casing string 78. The packer 82 is located between the production zone 72 and the injection zone 74. The geothermal fluid 102 in the subterranean formation 42 enters the well 70 at the production zone 72, and flows up the tubing string 76 to a wellhead 71. The geothermal fluid 102 flows from the wellhead 71 of the well 70 to the turbocharger 110. Operation of the turbocharger 110, the heat exchanger 26, the binary cycle power plant 10, the one or more turbines 140 (with associated generators 148), and the one or more pumps 134 is as described above. The one or more pumps 134 inject the geothermal fluid 102 into the annulus 80 of the well 70. The geothermal fluid 102 exits the well 70 at the injection zone 74, and enters the subterranean formation 42.PATENTAttorney Docket No.: SGEO / 0020PC

[0070] The geothermal fluid 102 flows in the subterranean formation 42 from the injection zone 74 of the well 70 through the fracture network 60 towards the production zone 72 of the well 70. The geothermal fluid 102 is heated by the subterranean formation 42. In some embodiments, the producing of the geothermal fluid 102 from the subterranean formation 42 via the well 70, and the injecting of the geothermal fluid 102 into the subterranean formation 42 at the well 70 are performed simultaneously.

[0071] In some embodiments, the first well 44 and the geothermal power system 100 are operated in a repeating alternating sequence of production of the geothermal fluid 102 from a specific location in the subterranean formation 42, then reinjection of the geothermal fluid 102 into the subterranean formation 42 at the same specific location. Such a sequence may be referred to as “huff and puff.” In an example, the first well 44 is coupled to the geothermal power system 100 via a flowline assembly 190, as schematically illustrated in Figure 1 D.

[0072] Line 192 conveys the geothermal fluid 102 from the first well 44 to the turbocharger 110. Line 194 conveys the geothermal fluid 102 from the one or more pumps 134 to the first well 44. When geothermal fluid 102 is flowing from the first well 44 to the turbocharger 110, valve 196 in line 192 is open, and valve 198 in line 194 is closed. When geothermal fluid 102 is flowing from the one or more pumps 134 to the first well 44, valve 198 in line 194 is open, and valve 196 in line 192 is closed.

[0073] The geothermal fluid 102 is produced from the subterranean formation 42 via the first well 44, and flows to the turbocharger 110 through line 192. The geothermal fluid 102 is utilized (as described above) in the geothermal power system 100, and then is stored in the reservoir 132. Then the flow of the geothermal fluid 102 from the first well 44 is ceased. Valve 196 of the flowline assembly 190 is closed, and valve 198 of the flowline assembly 190 is opened. Then the one or more pumps 134 pump the geothermal fluid 102 from the reservoir 132 back into the first well 44, and inject the geothermal fluid 102 into the first well 44, and into the subterranean formation 42. Valve 198 of the flowline assembly 190 is closed, and valve 196 of the flowline assembly 190 is opened. Then the sequence is repeated. In some embodiments, a time delay is implemented while the first well 44 is closed-in to allow the geothermalPATENTAttorney Docket No.: SGEO / 0020PC fluid 102 in the subterranean formation 42 (such as in the one or more fractures 62) to become heated by the subterranean formation 42 before reopening the first well 44.

[0074] Figure 2 schematically illustrates a geothermal power system 200. The geothermal power system 200 includes the binary cycle power plant 10, and utilizes the working fluid 12, as described above. The geothermal power system 200 utilizes the geothermal fluid 102 described above. In some embodiments, the working fluid 12 in the binary cycle power plant 10 is segregated from the geothermal fluid 102. In some embodiments, the working fluid 12 may include at least a portion of the geothermal fluid 102. In some embodiments, the geothermal fluid 102 may include at least a portion of the working fluid 12.

[0075] The geothermal fluid 102 is heated, or is maintained at an elevated temperature, by the subterranean formation 42. In an example, the temperature of the geothermal fluid 102 is at or about 150 degrees C or higher, such as 175 degrees C or higher, 200 degrees C or higher, 250 degrees C or higher, or 300 degrees C or higher. The geothermal fluid 102 is maintained at an elevated pressure in the subterranean formation 42. In an example, the pressure of the geothermal fluid 102 in the subterranean formation 42 is at or about 3 MPa or higher, such as 5 MPa or higher, 10 MPa or higher, 20 MPa or higher, 30 MPa or higher, 40 MPa or higher, or 50 MPa or higher. In some embodiments, the geothermal fluid 102 is geopressured. In an example, the geothermal fluid 102 may be a geopressured-geothermal fluid.

[0076] The geothermal fluid 102 flows from the subterranean formation 42 into the first well 44. In some embodiments, the geothermal fluid 102 flows from the subterranean formation 42 into the first well 44 via one or more fractures 62 in the subterranean formation 42 at the first well 44. In some embodiments, the temperature of the geothermal fluid 102 at the wellhead 45 of the first well 44 is at or near the temperature of the geothermal fluid 102 in the subterranean formation 42.

[0077] The geothermal fluid 102 flows from the first well 44 to a turbocharger 210. Any of turbocharger 800A, 800B, 800C, or 800D (all described below) may be used as turbocharger 210. In some embodiments, the geothermal power system 200 includes a plurality of turbochargers 210, such as in a parallel hookup configuration.PATENTAttorney Docket No.: SGEO / 0020PC

[0078] The geothermal fluid 102 flows into the turbocharger 210 at a first inlet 212, and exits the turbocharger 210 at a first outlet 214. The pressure of the geothermal fluid 102 is reduced as the geothermal fluid 102 transits through the turbocharger 210 from the first inlet 212 to the first outlet 214 along a first fluid path 216. In an example, the pressure of the geothermal fluid 102 at the first outlet 214 is at or about 20 MPa or less, such as 15 MPa or less, 10 MPa or less, 5 MPa or less, 3 MPa or less, 1 MPa or less, 0.5 MPa or less, or 0.2 MPa or less. The temperature of the geothermal fluid 102 at the first inlet 212 is at or near the temperature of the geothermal fluid 102 at the wellhead 45 of the first well 44. The temperature of the geothermal fluid 102 at the first outlet 214 is at or near the temperature of the geothermal fluid 102 at the first inlet 212.

[0079] The geothermal fluid 102 flows from the first outlet 214 of the turbocharger 210 to the heat exchanger 26. In some embodiments, the temperature of the geothermal fluid 102 entering the heat exchanger 26 is similar to the temperature of the geothermal fluid 102 at the first well 44. In an example, the geothermal fluid 102 is at or about 150 degrees C or higher, such as 175 degrees C or higher, 200 degrees C or higher, 250 degrees C or higher, or 300 degrees C or higher when entering the heat exchanger 26. Heat is transferred from the geothermal fluid 102 to the working fluid 12 as the geothermal fluid 102 flows through the heat exchanger 26. The temperature of the geothermal fluid 102 is lowered to a reduced level as the geothermal fluid 102 flows through the heat exchanger 26. In an example, the temperature of the geothermal fluid 102 upon exiting the heat exchanger 26 is at or about 100 degrees C or less, such as 90 degrees C or less, 80 degrees C or less, 70 degrees C or less, 60 degrees C or less, or 50 degrees C or less.

[0080] In some embodiments, the geothermal fluid 102 flows from the heat exchanger 26 to one or more pumps 230. Exemplary pumps 230 include single phase pumps, multi-phase pumps, centrifugal pumps, positive displacement pumps, or the like. In some embodiments, the geothermal fluid 102 flows from the heat exchanger 26 to an intermediate reservoir (such as a pond, a tank, or a subterranean formation different from subterranean formation 42), before flowing to the one or more pumpsPATENTAttorney Docket No.: SGEO / 0020PC230. In some embodiments, the intermediate reservoir is omitted. In some embodiments, the one or more pumps 230 are omitted.

[0081] The geothermal fluid 102 flows from the heat exchanger 26 or the intermediate reservoir (if present) via the one or more pumps 230 (if present) to a second inlet 222 of the turbocharger 210. In some embodiments, the intermediate reservoir functions as a buffer to facilitate controlling the flow rate of the geothermal fluid 102 from the heat exchanger 26 to the second inlet 222 of the turbocharger 210. In an example, the flow rate of the geothermal fluid 102 from the heat exchanger 26 to the second inlet 222 of the turbocharger 210 is controlled to smooth out spikes and dips. In another example, the flow rate of the geothermal fluid 102 from the heat exchanger 26 to the second inlet 222 of the turbocharger 210 is controlled to correspond to the flow rate of the geothermal fluid 102 from the first outlet 214 of the turbocharger 210 to the heat exchanger 26.

[0082] The geothermal fluid 102 flows into the turbocharger 210 at the second inlet 222, and exits the turbocharger 210 at a second outlet 224. The turbocharger 210 utilizes the pressure of the relatively hotter geothermal fluid 102 at the first inlet 212 to increase the pressure of the relatively colder geothermal fluid 102 that enters the turbocharger 210 at the second inlet 222. The pressure of the geothermal fluid 102 is increased as the geothermal fluid 102 transits through the turbocharger 210 from the second inlet 222 to the second outlet 224 along a second fluid path 226. The second fluid path 226 is separate from the first fluid path 216. In an example, the pressure of the geothermal fluid 102 at the second outlet 224 is at or about 3 MPa or higher, such as 5 MPa or higher, 10 MPa or higher, 20 MPa or higher, 30 MPa or higher, 40 MPa or higher, or 50 MPa or higher. In some embodiments, the pressure of the geothermal fluid 102 at the second outlet 224 is less than the pressure of the geothermal fluid 102 at the first inlet 212. In some embodiments, the pressure of the geothermal fluid 102 at the second outlet 224 is substantially equal to the pressure of the geothermal fluid 102 at the first inlet 212. In an example, the pressure of the geothermal fluid 102 at the second outlet 224 is 95% to 100% of the pressure of the geothermal fluid 102 at the first inlet 212. The temperature of the geothermal fluid 102 remains at or near thePATENTAttorney Docket No.: SGEO / 0020PC reduced level as the geothermal fluid 102 transits through the turbocharger 210 from the second inlet 222 to the second outlet 224 along the second fluid path 226.

[0083] The circuit of routing the geothermal fluid 102 through the turbocharger 210, then through the heat exchanger 26, then back through the turbocharger 210 provides several benefits. For example, the heat exchanger 26 may be designed to operate at pressures that are lower than the pressure of the geothermal fluid 102 at the wellhead 45, which avoids the expense and inefficiencies of so-called “high pressure heat exchangers” configured to operate at pressures higher than conventional heat exchangers. Additionally, the pressure of the geothermal fluid 102 itself exiting the first well 44 is used to boost the pressure of the geothermal fluid 102 exiting the heat exchanger 26, which avoids the expense and inefficiencies of pumps that operate at pressure ratios (outlet pressure divided by inlet pressure) of ten or more. The pressure of the geothermal fluid 102 at the wellhead 45 is usefully employed, rather than being wasted.

[0084] In some embodiments, the geothermal fluid 102 flows from the turbocharger 210 to one or more pumps 234. Exemplary pumps 234 include single phase pumps, multi-phase pumps, centrifugal pumps, positive displacement pumps, or the like. The one or more pumps 234 increase a pressure of the geothermal fluid 102, and inject the geothermal fluid 102 into the second well 46. In some embodiments, the one or more pumps 234 are booster pumps. In an example, the pressure increase provided by the one or more pumps 234 is less than an inlet pressure of the one or more pumps 234. In some embodiments, the one or more pumps 234 are operated at an efficiency of 90% or above, such as 92% or above, or 95% or above.

[0085] In some embodiments, the pressure of the geothermal fluid 102 at the second outlet 224 of the turbocharger 210 is greater than the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46. In some of such embodiments, the geothermal fluid 102 flows through a bypass 236 of the one or more pumps 234 when flowing from the turbocharger 210 to the second well 46. As flow of the geothermal fluid 102 continues, the pressure at the wellhead 47 of the second well 46 increases. The pressure at the second outlet 224 of the turbocharger 210 and the pressure at the wellhead 47 of the second well 46 approach an equilibrium. Prior to,PATENTAttorney Docket No.: SGEO / 0020PC or upon, the pressures at the second outlet 224 of the turbocharger 210 and at the wellhead 47 reaching an equilibrium, the geothermal fluid 102 is routed to the one or more pumps 234, which pump the geothermal fluid 102 into the second well 46.

[0086] In some embodiments, additional geothermal fluid 102 is injected into the second well 46 from a reservoir 240 (such as a pond, a tank, or a subterranean formation different from subterranean formation 42), using one or more charge pumps 242. Exemplary charge pumps 242 include single phase pumps, multi-phase pumps, centrifugal pumps, positive displacement pumps, or the like. In some embodiments, the additional geothermal fluid 102 is a make-up fluid that compensates for losses of geothermal fluid 102 into the subterranean formation 42. In some embodiments, the one or more charge pumps 242 pump geothermal fluid 102 from the reservoir 240 into the second well 46 to establish a selected operating pressure at the wellhead 47 of the second well 46. The operating pressure at the wellhead 47 of the second well 46 may be selected such that the one or more fractures 64 in the subterranean formation 42 are open.

[0087] In some embodiments, the one or more charge pumps 242 are fluidically coupled to the wellhead 47 via the flowline from the one or more pumps 234 (or the bypass 236) to the wellhead 47. In some embodiments, the one or more charge pumps 242 are fluidically coupled directly to the wellhead 47 via a separate flowline.

[0088] In some embodiments, the one or more charge pumps 242 are operated intermittently to pump geothermal fluid 102 from the reservoir 240 and into the second well 46 while geothermal fluid 102 flows from the turbocharger 210 to the second well 46. In some embodiments, the one or more charge pumps 242 are operated continuously to pump geothermal fluid 102 from the reservoir 240 and into the second well 46 while geothermal fluid 102 flows from the turbocharger 210 to the second well 46. In some embodiments, the reservoir 240 and the one or more charge pumps 242 may be omitted.

[0089] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 45 of the first well 44 is maintained at a magnitude such that the one or more fractures 62 remain open while flowing the geothermal fluid 102 to the turbochargerPATENTAttorney Docket No.: SGEO / 0020PC210. In an example, the flow of the geothermal fluid 102 out of the first well 44 is choked by the valve 52. In another example, the turbocharger 210 is operated such that a back-pressure is exerted on the geothermal fluid 102 at the wellhead 45 of the first well 44.

[0090] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 is maintained at a magnitude such that the one or more fractures 64 remain open. In an example, the one or more pumps 234 are operated to maintain the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 at a magnitude such that the one or more fractures 64 remain open. In another example, the turbocharger 210 is operated such that the pressure of the geothermal fluid 102 exiting the turbocharger 210 at the second outlet 224 is at a magnitude such that the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 is sufficient to maintain the one or more fractures 64 open. In a further example, the one or more charge pumps 242 (if present) are operated such that the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 is sufficient to maintain the one or more fractures 64 open.

[0091] In some embodiments, the one or more fractures 62 intersect with the one or more fractures 64. In some embodiments, the one or more fractures 62 are contiguous with the one or more fractures 64. In some embodiments, the geothermal fluid 102 flows within the subterranean formation 42 from the second well 46 to the first well 44, and is produced again from the first well 44.

[0092] As illustrated, in some embodiments, the geothermal fluid 102 does not flow within the subterranean formation 42 from the second well 46 to the first well 44. In an example, the one or more fractures 62 do not intersect with the one or more fractures 64. In another example, the one or more fractures 62 are not contiguous with the one or more fractures 64. In such embodiments, the geothermal power system 200 is reconfigured to flow the geothermal fluid 102 from the second well 46 to the turbocharger 210, and to flow the returning geothermal fluid 102 from the one or more pumps 234 to the first well 44. In an example, the geothermal power system 200 includes the manifold assembly 150, described above.PATENTAttorney Docket No.: SGEO / 0020PC

[0093] When the geothermal power system 200 includes the manifold assembly 150, line 162 fluidically couples the production manifold 160 with the turbocharger 210. When the geothermal power system 200 includes the manifold assembly 150, line 172 fluidically couples the one or more pumps 234 (or the bypass 236) to the injection manifold 170. In some embodiments, when the geothermal power system 200 includes the manifold assembly 150, line 172 fluidically couples the one or more charge pumps 242 to the injection manifold 170. In some embodiments, when the geothermal power system 200 includes the manifold assembly 150, an additional line fluidically couples the one or more charge pumps 242 to the injection manifold 170. The manifold assembly 150, first well 44, second well 46, third well (if present), and fourth well (if present) are operated as described above.

[0094] Additionally, or alternatively, the geothermal power system 200 is coupled to the well 70, as described above. In such embodiments, the well 70 is operated as described above when coupled to the geothermal power system 200. The geothermal fluid 102 produced from the subterranean formation 42 at the production zone 72 flows up the tubing string 76 to the wellhead 71 , and from the wellhead 71 to the turbocharger 210. The geothermal fluid 102 flows from the one or more pumps 234 or the bypass 236 into the annulus 80, and into the subterranean formation 42 at the injection zone 74. In some embodiments, the one or more charge pumps 242 pump additional geothermal fluid 102 from the reservoir 240 into the annulus 80, and into the subterranean formation 42 at the injection zone 74.

[0095] Additionally, or alternatively, the first well 44 is coupled to the geothermal power system 200 via the flowline assembly 190 (Figure 1 D), such as described above. In such embodiments, the first well 44 is operated as described above when coupled to the geothermal power system 200 via the flowline assembly 190. The geothermal fluid 102 produced from the subterranean formation 42 via the first well 44 flows through line 192 to the turbocharger 210. The geothermal fluid 102 flows from the one or more pumps 234 or the bypass 236 through line 194 back to the first well 44, and is reinjected into the subterranean formation 42. In some embodiments, the one or more charge pumps 242 pump additional geothermal fluid 102 from the reservoir 240 through line 194 to the first well 44, and inject the additional geothermalPATENTAttorney Docket No.: SGEO / 0020PC fluid 102 into the subterranean formation 42. When geothermal fluid 102 is flowing from the first well 44 to the turbocharger 210, valve 196 in line 192 is open, and valve 198 in line 194 is closed. When geothermal fluid 102 is flowing from the one or more pumps 234 and / or the one or more charge pumps 242 to the first well 44, valve 198 in line 194 is open, and valve 196 in line 192 is closed. In some embodiments, the first well 44 and the geothermal power system 200 are operated in a repeating alternating sequence of production of the geothermal fluid 102 from the subterranean formation 42, then reinjection of the geothermal fluid 102 into the subterranean formation 42 (“huff-and-puff”), such as described above.

[0096] Figure 3 schematically illustrates a geothermal power system 300. The geothermal power system 300 includes a binary cycle power plant 10A that utilizes the working fluid 12, as described above. Binary cycle power plant 10A is similar to binary cycle power plant 10 described above, except that after passing through the heat exchanger 26, the working fluid 12 passes through a turbocharger 310 before entering the expander 30.

[0097] The geothermal power system 300 utilizes the geothermal fluid 102 described above. In some embodiments, the working fluid 12 in the binary cycle power plant 10 is segregated from the geothermal fluid 102. In some embodiments, the working fluid 12 may include at least a portion of the geothermal fluid 102. In some embodiments, the geothermal fluid 102 may include at least a portion of the working fluid 12.

[0098] The geothermal fluid 102 is heated, or is maintained at an elevated temperature, by the subterranean formation 42. In an example, the temperature of the geothermal fluid 102 is at or about 150 degrees C or higher, such as 175 degrees C or higher, 200 degrees C or higher, 250 degrees C or higher, or 300 degrees C or higher. The geothermal fluid 102 is maintained at an elevated pressure in the subterranean formation 42. In an example, the pressure of the geothermal fluid 102 in the subterranean formation 42 is at or about 3 MPa or higher, such as 5 MPa or higher, 10 MPa or higher, 20 MPa or higher, 30 MPa or higher, 40 MPa or higher, or 50 MPa or higher. In some embodiments, the geothermal fluid 102 is geopressured. In an example, the geothermal fluid 102 may be a geopressured-geothermal fluid.PATENTAttorney Docket No.: SGEO / 0020PC

[0099] The geothermal fluid 102 flows from the subterranean formation 42 into the first well 44. In some embodiments, the geothermal fluid 102 flows from the subterranean formation 42 into the first well 44 via one or more fractures 62 in the subterranean formation 42 at the first well 44. In some embodiments, the temperature of the geothermal fluid 102 at the wellhead 45 of the first well 44 is at or near the temperature of the geothermal fluid 102 in the subterranean formation 42.

[0100] The geothermal fluid 102 flows from the first well 44 to a turbocharger 310. Any of turbocharger 800A, 800B, 800C, or 800D (all described below) may be used as turbocharger 310. In some embodiments, the geothermal power system 300 includes a plurality of turbochargers 310, such as in a parallel hookup configuration.

[0101] The geothermal fluid 102 flows into the turbocharger 310 at a first inlet 312, and exits the turbocharger 310 at a first outlet 314. The pressure of the geothermal fluid 102 is reduced as the geothermal fluid 102 transits through the turbocharger 310 from the first inlet 312 to the first outlet 314 along a first fluid path 316. In an example, the pressure of the geothermal fluid 102 at the first outlet 314 is at or about 20 MPa or less, such as 15 MPa or less, 10 MPa or less, 5 MPa or less, 3 MPa or less, 1 MPa or less, 0.5 MPa or less, or 0.2 MPa or less. The temperature of the geothermal fluid 102 at the first inlet 312 is at or near the temperature of the geothermal fluid 102 at the wellhead 45 of the first well 44. The temperature of the geothermal fluid 102 at the first outlet 314 is at or near the temperature of the geothermal fluid 102 at the first inlet 312.

[0102] The geothermal fluid 102 flows from the first outlet 314 of the turbocharger 310 to the heat exchanger 26. In some embodiments, the temperature of the geothermal fluid 102 entering the heat exchanger 26 is similar to the temperature of the geothermal fluid 102 at the first outlet 314, such as at or near the temperature of the geothermal fluid 102 at the first inlet 312 or at the first well 44. In an example, the geothermal fluid 102 is at or about 150 degrees C or higher, such as 175 degrees C or higher, 200 degrees C or higher, 250 degrees C or higher, or 300 degrees C or higher when entering the heat exchanger 26.PATENTAttorney Docket No.: SGEO / 0020PC

[0103] Heat is transferred from the geothermal fluid 102 to the working fluid 12 as the geothermal fluid 102 flows through the heat exchanger 26. The temperature of the geothermal fluid 102 is lowered to a reduced level as the geothermal fluid 102 flows through the heat exchanger 26. In an example, the temperature of the geothermal fluid 102 upon exiting the heat exchanger 26 is at or about 100 degrees C or less, such as 90 degrees C or less, 80 degrees C or less, 70 degrees C or less, 60 degrees C or less, or 50 degrees C or less. In an example, at the heat exchanger 26, the temperature of the working fluid 12 is increased to 100 degrees C or higher, such as 125 degrees C or higher, 150 degrees C or higher, 175 degrees C or higher, or 200 degrees C or higher.

[0104] The geothermal fluid 102 flows through the turbocharger 310 and then through the heat exchanger 26. The working fluid 12 flows in the opposite direction to the geothermal fluid 102. The working fluid 12 flows through the heat exchanger 26 and then through the turbocharger 310.

[0105] The working fluid 12 flows into the turbocharger 310 at a second inlet 322, and exits the turbocharger 310 at a second outlet 324. The turbocharger 310 utilizes the pressure of the geothermal fluid 102 at the first inlet 212 to increase the pressure of the working fluid 12. The pressure of the working fluid 12 is increased as the working fluid 12 transits through the turbocharger 310 from the second inlet 322 to the second outlet 324 along a second fluid path 326. The second fluid path 326 is separate from the first fluid path 316. In an example, the pressure of the working fluid 12 at the second outlet 324 is at or about 5 MPa or higher, such as 7.5 MPa or higher, 10 MPa or higher, 12.5 MPa or higher, or 15 MPa or higher.

[0106] The transfer of heat energy from the geothermal fluid 102 to the working fluid 12 occurs while both the geothermal fluid 102 and the working fluid 12 are at relatively low pressures compared to the pressures of the geothermal fluid 102 and the working fluid 12 at one or more other stages of the geothermal power system 300. For example, the pressure of the geothermal fluid 102 at the heat exchanger 26 is lower than the pressure of the geothermal fluid 102 at the first inlet 312 of the turbocharger 310. Additionally, the pressure of the working fluid 12 at the heatPATENTAttorney Docket No.: SGEO / 0020PC exchanger 26 is lower than the pressure of the working fluid 12 at the second outlet 324 of the turbocharger 310.

[0107] The transfer of pressure energy from the geothermal fluid 102 to the working fluid 12 occurs while both the geothermal fluid 102 and the working fluid 12 are at relatively high temperatures compared to the temperatures of the geothermal fluid 102 and the working fluid 12 at one or more other stages of the geothermal power system 300. For example, the temperature of the geothermal fluid 102 at the turbocharger 310 is greater than the temperature of the geothermal fluid 102 exiting the heat exchanger 26. Additionally, the temperature of the working fluid 12 at the turbocharger 310 is greater than the temperature of the working fluid 12 entering the heat exchanger 26.

[0108] In some embodiments, the temperature of the working fluid 12 at the second outlet 324 is at or near the temperature of the working fluid 12 at the second inlet 322 of the turbocharger 310. In some embodiments, the temperature of the working fluid 12 at the second outlet 324 is at or near the temperature of the working fluid 12 exiting the heat exchanger 26.

[0109] The working fluid 12 flows from the turbocharger 310 to the expander 30. The working fluid 12 loses heat and pressure as the working fluid 12 drives the expander 30 and the associated generator 36 to generate electricity. For example, the pressure of the working fluid 12 exiting the expander 30 may be at or about 5 MPa or lower, such as 4 MPa or lower, 3 MPa or lower, 2 MPa or lower, 1 MPa or lower, or 0.5 MPa or lower. Additionally, the temperature of the working fluid 12 exiting the expander 30 may be at or about 100 degrees C or less, such as 90 degrees C or less, 80 degrees C or less, 70 degrees C or less, 60 degrees C or less, or 50 degrees C or less.

[0110] The working fluid 12 flows from the expander 30 through the recuperator 24 and the condenser 20, as described above. The working fluid 12 flows from the condenser 20 to a pressure booster, such as pressure booster 22 (Figure 1A). In some embodiments, in binary cycle power plant 10A, the pressure booster 22 is replaced by pressure booster 22A. The pressure booster 22A, such as a pump (e.g.PATENTAttorney Docket No.: SGEO / 0020PC a single phase pump, a multi-phase pump, a centrifugal pump, or a positive displacement pump), a compressor, or the like. The pressure booster 22A may be sized to provide a smaller pressure boost to the working fluid 12 than would be provided by the pressure booster 22.

[0111] The pressure booster 22A increases the pressure of the working fluid 12, and moves the working fluid 12 through the recuperator 24 to the heat exchanger 26, where the working fluid 12 is heated, as described above. In some embodiments, the turbocharger 310 provides a majority of the boost in pressure to the working fluid 12 after the working fluid 12 exits the condenser 20 prior to entering the expander 30. In some embodiments, the pressure booster 22A provides a majority of the boost in pressure to the working fluid 12 after the working fluid 12 exits the condenser 20 prior to entering the expander 30. In some embodiments, the turbocharger 310 and the pressure booster 22A provide a substantially equal amount of the boost in pressure to the working fluid 12 after the working fluid 12 exits the condenser 20 prior to entering the expander 30.

[0112] As described above, the geothermal power system 300 transfers heat energy and pressure energy of the geothermal fluid 102 to the working fluid 12 of the binary cycle power plant 10A. The binary cycle power plant 10A converts the transferred heat energy and pressure energy into electricity.

[0113] Turning back to the flow of the geothermal fluid 102, the geothermal fluid 102 flows from the heat exchanger 26 to one or more pumps 334. Exemplary pumps 334 include single phase pumps, multi-phase pumps, centrifugal pumps, positive displacement pumps, or the like. The one or more pumps 334 increase a pressure of the geothermal fluid 102, and inject the geothermal fluid 102 into the second well 46. The geothermal fluid 102 flows through the second well 46, and enters the one or more fractures 64 in the subterranean formation 42.

[0114] In some embodiments, the geothermal fluid 102 flows from the heat exchanger 26 to a reservoir 332 (such as a pond, a tank, or a subterranean formation different from subterranean formation 42), before flowing to the one or more pumps 334. In some embodiments, the reservoir 332 provides for temporary storage of thePATENTAttorney Docket No.: SGEO / 0020PC geothermal fluid 102 prior to injecting the geothermal fluid 102 into the second well 46. In an example, the geothermal fluid 102 is utilized in the geothermal power system 300 to produce electricity and is stored in reservoir 332 during a period of relatively high demand for electricity, then is injected into the second well 46 during a subsequent period of relatively low demand for electricity. In some embodiments, the reservoir 332 is omitted.

[0115] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 45 of the first well 44 is maintained at a magnitude such that the one or more fractures 62 remain open while flowing the geothermal fluid 102 to the turbocharger 310. In an example, the flow of the geothermal fluid 102 out of the first well 44 is choked by valve 52. In another example, the turbocharger 310 is operated such that a back-pressure is exerted on the geothermal fluid 102 at the wellhead 45 of the first well 44.

[0116] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 is maintained at a magnitude such that the one or more fractures 64 remain open. In an example, the one or more pumps 334 are operated to maintain the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 at a magnitude such that the one or more fractures 64 remain open.

[0117] In some embodiments, the one or more fractures 62 intersect with the one or more fractures 64. In some embodiments, the one or more fractures 62 are contiguous with the one or more fractures 64. In some embodiments, the geothermal fluid 102 flows within the subterranean formation 42 from the second well 46 to the first well 44, and is produced again from the first well 44.

[0118] As illustrated, in some embodiments, the geothermal fluid 102 does not flow within the subterranean formation 42 from the second well 46 to the first well 44. In an example, the one or more fractures 62 do not intersect with the one or more fractures 64. In another example, the one or more fractures 62 are not contiguous with the one or more fractures 64. In such embodiments, the geothermal power system 300 is reconfigured to flow the geothermal fluid 102 from the second well 46 to the turbocharger 310, and to flow the returning geothermal fluid 102 from the onePATENTAttorney Docket No.: SGEO / 0020PC or more pumps 334 to the first well 44. In an example, the geothermal power system 300 includes the manifold assembly 150, described above.

[0119] When the geothermal power system 300 includes the manifold assembly 150, line 162 fluidically couples the production manifold 160 with the turbocharger 310. When the geothermal power system 300 includes the manifold assembly 150, line 172 fluidically couples the one or more pumps 334 to the injection manifold 170. The manifold assembly 150, first well 44, second well 46, third well (if present), and fourth well (if present) are operated as described above.

[0120] Additionally, or alternatively, the geothermal power system 300 is coupled to the well 70, as described above. In such embodiments, the well 70 is operated as described above when coupled to the geothermal power system 300. The geothermal fluid 102 produced from the subterranean formation 42 at the production zone 72 flows up the tubing string 76 to the wellhead 71 , and from the wellhead 71 to the turbocharger 310. The geothermal fluid 102 flows from the one or more pumps 334 into the annulus 80, and into the subterranean formation 42 at the injection zone 74.

[0121] Additionally, or alternatively, the first well 44 is coupled to the geothermal power system 300 via the flowline assembly 190 (Figure 1 D), such as described above. In such embodiments, the first well 44 is operated as described above when coupled to the geothermal power system 300 via the flowline assembly 190. The geothermal fluid 102 produced from the subterranean formation 42 via the first well 44 flows through line 192 to the turbocharger 310. The geothermal fluid 102 flows from the one or more pumps 334 through line 194 back to the first well 44, and is reinjected into the subterranean formation 42. When geothermal fluid 102 is flowing from the first well 44 to the turbocharger 310, valve 196 in line 192 is open, and valve 198 in line 194 is closed. When geothermal fluid 102 is flowing from the one or more pumps 334 to the first well 44, valve 198 in line 194 is open, and valve 196 in line 192 is closed. In some embodiments, the first well 44 and the geothermal power system 300 are operated in a repeating alternating sequence of production of the geothermal fluid 102 from the subterranean formation 42, then reinjection of the geothermal fluid 102 into the subterranean formation 42 (“huff-and-puff”), such as described above.PATENTAttorney Docket No.: SGEO / 0020PC

[0122] Figure 4 schematically illustrates a geothermal power system 400. The geothermal power system 400 utilizes the geothermal fluid 102. The geothermal fluid 102 is heated, or is maintained at an elevated temperature, by the subterranean formation 42. In an example, the temperature of the geothermal fluid 102 is at or about 150 degrees C or higher, such as 175 degrees C or higher, 200 degrees C or higher, 250 degrees C or higher, or 300 degrees C or higher. The geothermal fluid 102 is maintained at an elevated pressure in the subterranean formation 42. In an example, the pressure of the geothermal fluid 102 in the subterranean formation 42 is at or about 3 MPa or higher, such as 5 MPa or higher, 10 MPa or higher, 20 MPa or higher, 30 MPa or higher, 40 MPa or higher, or 50 MPa or higher. In some embodiments, the geothermal fluid 102 is geopressured. In an example, the geothermal fluid 102 may be a geopressured-geothermal fluid.

[0123] The geothermal fluid 102 flows from the subterranean formation 42 into the first well 44. In some embodiments, the geothermal fluid 102 flows from the subterranean formation 42 into the first well 44 via the one or more fractures 62 in the subterranean formation 42 at the first well 44. In some embodiments, the temperature of the geothermal fluid 102 at the wellhead 45 of the first well 44 is at or near the temperature of the geothermal fluid 102 in the subterranean formation 42.

[0124] The geothermal fluid 102 flows from the first well 44 to a turbocharger 410. Any of turbocharger 800A, 800B, 800C, or 800D (all described below) may be used as turbocharger 410. In some embodiments, the geothermal power system 400 includes a plurality of turbochargers 410, such as in a parallel hookup configuration.

[0125] The geothermal fluid 102 flows into the turbocharger 410 at a first inlet 412, and exits the turbocharger 410 at a first outlet 414. The pressure of the geothermal fluid 102 is reduced as the geothermal fluid 102 transits through the turbocharger 410 from the first inlet 412 to the first outlet 414 along a first fluid path 416. In an example, the pressure of the geothermal fluid 102 at the first outlet 414 is at or about 20 MPa or less, such as 15 MPa or less, 10 MPa or less, 5 MPa or less, 3 MPa or less, 1 MPa or less, 0.5 MPa or less, or 0.2 MPa or less. The temperature of the geothermal fluid 102 at the first inlet 412 is at or near the temperature of the geothermal fluid 102 at the wellhead 45 of the first well 44. The temperature of the geothermal fluid 102 atPATENTAttorney Docket No.: SGEO / 0020PC the first outlet 414 is at or near the temperature of the geothermal fluid 102 at the first inlet 412.

[0126] The turbocharger 410 forms part of a power fluid circuit 440 that utilizes a power fluid (represented by arrows 442), such as water, steam, brine, a refrigerant, a supercritical fluid, carbon dioxide, ammonia, an organic compound (e.g., a hydrocarbon, a fluorocarbon, etc.), or any combination thereof. In some embodiments, the power fluid 442 is free, or substantially free, of suspended solids. In an example, the power fluid 442 has a suspended solids content of 0.5% by volume or less, such as 0.1 % by volume or less, 0.05% by volume or less, 0.01 % by volume or less, 0.005% by volume or less, or 0.001 % by volume or less,. The power fluid 442 flows into the turbocharger 410 at a second inlet 422, and exits the turbocharger 410 at a second outlet 424. The turbocharger 410 utilizes the pressure of the geothermal fluid 102 at the first inlet 412 to increase the pressure of the power fluid 442. The pressure of the power fluid 442 is increased as the power fluid 442 transits through the turbocharger 410 from the second inlet 422 to the second outlet 424 along a second fluid path 426. The second fluid path 426 is separate from the first fluid path 416. In an example, the pressure of the power fluid 442 at the second outlet 424 is at or about 3 MPa or higher, such as 5 MPa or higher, 10 MPa or higher, 20 MPa or higher, 30 MPa or higher, 40 MPa or higher, or 50 MPa or higher. In some embodiments, the pressure of the power fluid 442 at the second outlet 424 is less than the pressure of the geothermal fluid 102 at the first inlet 412.

[0127] The power fluid 442 flows from the turbocharger 410 to one or more turbines 444. In some embodiments, the one or more turbines 444 are Pelton Turbines. In some embodiments, the one or more turbines 444 are other types of turbine, such as Francis Turbines or Kaplan Turbines. In some embodiments, the one or more turbines 444 are located at the earth’s surface 40. In some embodiments, the one or more turbines 444 include a plurality of turbines 444 arranged in a series configuration such that the power fluid 442 flows to a first turbine 444 and then to a second turbine 444. In some embodiments, the one or more turbines 444 include a plurality of turbines 444 arranged in a parallel configuration. In an example, a first portion of the power fluid 442 flows to a first turbine 444, and a different second portion of the power fluid 442PATENTAttorney Docket No.: SGEO / 0020PC flows simultaneously to a second turbine 444. In another example, one of the first or second turbines 444 is offline (such as for maintenance), and the power fluid 442 flows to the other of the first or second turbines 444.

[0128] Each of the one or more turbines 444 is coupled to a corresponding shaft 446. Each shaft 446 is coupled to a corresponding generator 448. In an example, each shaft 446 is coupled to the corresponding generator 448 via a gearbox. Each turbine 444 drives the corresponding shaft 446, which drives the corresponding generator 448 to produce electricity.

[0129] In some embodiments, the power fluid 442 enters each turbine 444 at a temperature that is substantially equal to the temperature of the power fluid 442 at the second outlet 424 of the turbocharger 410. In an example, the temperature of the power fluid 442 at each turbine 444 is within 10 degrees C, such as within 7 degrees C, within 5 degrees C, or within 2 degrees C, of the temperature of the power fluid 442 at the second outlet 324 of the turbocharger 410. In some embodiments, the power fluid 442 does not flow through a heat exchanger between the second outlet 424 of the turbocharger 410 and the one or more turbines 344.

[0130] The power fluid 442 flows through each turbine 444, and experiences a drop in pressure as the power fluid 442 drives each turbine 444 to rotate the corresponding shaft 446, and drive the corresponding generator 448 to produce electricity. In an example, the pressure of the power fluid 442 exiting each turbine 344 is at or about 1 MPa or less, such as 0.5 MPa or less, 0.4 MPa or less, 0.3 MPa or less, or 0.2 MPa or less. The power fluid 442 flows from each of the one or more turbines 444 back to the second inlet 422 of the turbocharger 410.

[0131] In some embodiments, the power fluid 442 enters the second inlet 422 of the turbocharger 310 at a temperature that is substantially equal to the temperature of the power fluid 442 exiting each of the one or more turbines 444. In an example, the temperature of the power fluid 442 at the second inlet 422 of the turbocharger 410 is within 10 degrees C, such as within 7 degrees C, within 5 degrees C, or within 2 degrees C, of the temperature of the power fluid 442 exiting each of the one or more turbines 444. In some embodiments, the power fluid 442 does not flow through a heatPATENTAttorney Docket No.: SGEO / 0020PC exchanger between each of the one or more turbines 444 and the second inlet 422 of the turbocharger 410. In some embodiments, the power fluid 442 exits the second outlet 424 of the turbocharger 410 at a temperature that is substantially equal to the temperature of the power fluid 442 at the second inlet 422 of the turbocharger 410.

[0132] The geothermal fluid 102 flows from the first outlet 414 of the turbocharger 410 to one or more pumps 434. Exemplary pumps 434 include single phase pumps, multi-phase pumps, centrifugal pumps, positive displacement pumps, or the like. The one or more pumps 434 increase a pressure of the geothermal fluid 102, and inject the geothermal fluid 102 into the second well 46. In some embodiments, the geothermal fluid 102 flows from the first outlet 414 of the turbocharger 410 to a reservoir 430 (such as a pond, a tank, or a subterranean formation different from subterranean formation 42), before flowing to the one or more pumps 434. In some embodiments, the reservoir 430 is omitted.

[0133] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 45 of the first well 44 is maintained at a magnitude such that the one or more fractures 62 remain open while the one or more pumps 434 pump the geothermal fluid 102 into the second well 46. In an example, the flow of the geothermal fluid 102 out of the first well 44 is choked by the valve 52. In another example, the turbocharger 410 is operated such that a back-pressure is exerted on the geothermal fluid at the wellhead 45 of the first well 44.

[0134] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 is maintained at a magnitude such that the one or more fractures 64 remain open. In an example, the one or more pumps 434 are operated to maintain the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 at a magnitude such that the one or more fractures 64 remain open.

[0135] In some embodiments, the one or more fractures 62 intersect with the one or more fractures 64. In some embodiments, the one or more fractures 62 are contiguous with the one or more fractures 64. In some embodiments, the geothermal fluid 102 flows within the subterranean formation 42 from the second well 46 to the first well 44, and is produced again from the first well 44.PATENTAttorney Docket No.: SGEO / 0020PC

[0136] As illustrated, in some embodiments, the geothermal fluid 102 does not flow within the subterranean formation 42 from the second well 46 to the first well 44. In an example, the one or more fractures 62 do not intersect with the one or more fractures 64. In another example, the one or more fractures 62 are not contiguous with the one or more fractures 64. In such embodiments, the geothermal power system 400 is reconfigured to flow the geothermal fluid 102 from the second well 46 to the turbocharger 410, and to flow the returning geothermal fluid 102 from the one or more pumps 434 to the first well 44. In an example, the geothermal power system 400 includes the manifold assembly 150, described above. When the geothermal power system 400 includes the manifold assembly 150, line 162 fluidically couples the production manifold 160 with the turbocharger 410. The manifold assembly 150, first well 44, second well 46, third well (if present), and fourth well (if present) are operated as described above.

[0137] Additionally, or alternatively, the geothermal power system 400 is coupled to the well 70, as described above. In such embodiments, the well 70 is operated as described above when coupled to the geothermal power system 400.

[0138] Additionally, or alternatively, the first well 44 is coupled to the geothermal power system 400 via the flowline assembly 190 (Figure 1 D), such as described above. In such embodiments, the first well 44 is operated as described above when coupled to the geothermal power system 400 via the flowline assembly 190. Line 192 conveys the geothermal fluid 102 from the first well 44 to the turbocharger 410. Line 194 conveys the geothermal fluid 102 from the one or more pumps 434 to the first well 44. When geothermal fluid 102 is flowing from the first well 44 to the turbocharger 410, valve 196 in line 192 is open, and valve 198 in line 194 is closed. When geothermal fluid 102 is flowing from the one or more pumps 434 to the first well 44, valve 198 in line 194 is open, and valve 196 in line 192 is closed.

[0139] In some embodiments, the first well 44 and the geothermal power system 400 are operated in a repeating alternating sequence of production of the geothermal fluid 102 from the subterranean formation 42, then reinjection of the geothermal fluid 102 into the subterranean formation 42 (“huff and puff”), such as described above. In examples of such embodiments, the geothermal fluid 102 is produced from thePATENTAttorney Docket No.: SGEO / 0020PC subterranean formation 42 via the first well 44, and utilized (as described above) in the geothermal power system 400. The geothermal fluid 102 is then stored in the reservoir 430. Then the flow of the geothermal fluid 102 from the first well 44 is ceased. Valve 196 of the flowline assembly 190 is closed, and valve 198 of the flowline assembly 190 is opened. Then the one or more pumps 434 pump the geothermal fluid 102 from the reservoir 430 back into the first well 44, and inject the geothermal fluid 102 into the subterranean formation 42. Valve 198 of the flowline assembly 190 is closed, and valve 196 of the flowline assembly 190 is opened. Then the sequence is repeated. In some embodiments, a time delay is implemented while the first well 44 is closed-in to allow the geothermal fluid 102 in the subterranean formation 42 (such as in the one or more fractures 62) to become heated by the subterranean formation 42 before reopening the first well 44.

[0140] Figure 5 schematically illustrates a geothermal power system 500. The geothermal power system 500 utilizes the geothermal fluid 102. The geothermal fluid 102 is heated, or is maintained at an elevated temperature, by the subterranean formation 42. In an example, the temperature of the geothermal fluid 102 is at or about 150 degrees C or higher, such as 175 degrees C or higher, 200 degrees C or higher, 250 degrees C or higher, or 300 degrees C or higher. The geothermal fluid 102 is maintained at an elevated pressure in the subterranean formation 42. In an example, the pressure of the geothermal fluid 102 in the subterranean formation 42 is at or about 3 MPa or higher, such as 5 MPa or higher, 10 MPa or higher, 20 MPa or higher, 30 MPa or higher, 40 MPa or higher, or 50 MPa or higher. In some embodiments, the geothermal fluid 102 is geopressured. In an example, the geothermal fluid 102 may be a geopressured-geothermal fluid.

[0141] The geothermal power system 500 includes a combination of at least a portion of geothermal power system 200 and at least a portion of geothermal power system 400. The geothermal fluid 102 flows from the subterranean formation 42 into the first well 44, as described above. In some embodiments, the temperature of the geothermal fluid 102 at the wellhead 45 of the first well 44 is at or near the temperature of the geothermal fluid 102 in the subterranean formation 42.PATENTAttorney Docket No.: SGEO / 0020PC

[0142] The geothermal fluid 102 flows from the first well 44 to the turbocharger 210. The geothermal fluid 102 flows into the turbocharger 210 at the first inlet 212, and exits the turbocharger 210 at the first outlet 214. The pressure of the geothermal fluid 102 is reduced as the geothermal fluid 102 transits through the turbocharger 210 from the first inlet 212 to the first outlet 214 along the first fluid path 216. In an example, the pressure of the geothermal fluid 102 at the first outlet 214 is at or about 20 MPa or less, such as 15 MPa or less, 10 MPa or less, 5 MPa or less, 3 MPa or less, 1 MPa or less, 0.5 MPa or less, or 0.2 MPa or less. The temperature of the geothermal fluid 102 at the first inlet 212 is at or near the temperature of the geothermal fluid 102 at the wellhead 45 of the first well 44. The temperature of the geothermal fluid 102 at the first outlet 214 is at or near the temperature of the geothermal fluid 102 at the first inlet 212.

[0143] The geothermal fluid 102 flows from the first outlet 214 of the turbocharger 210 to the heat exchanger 26. In some embodiments, the temperature of the geothermal fluid 102 entering the heat exchanger 26 is similar to the temperature of the geothermal fluid 102 at the first well 44. In an example, the geothermal fluid 102 is at or about 150 degrees C or higher, such as 175 degrees C or higher, 200 degrees C or higher, 250 degrees C or higher, or 300 degrees C or higher when entering the heat exchanger. Heat is transferred from the geothermal fluid 102 to the working fluid 12 as the geothermal fluid 102 flows through the heat exchanger 26. The temperature of the geothermal fluid 102 is lowered to a reduced level as the geothermal fluid 102 flows through the heat exchanger 26. In an example, the temperature of the geothermal fluid 102 upon exiting the heat exchanger 26 is at or about 100 degrees C or less, such as 90 degrees C or less, 80 degrees C or less, 70 degrees C or less, 60 degrees C or less, or 50 degrees C or less.

[0144] In some embodiments, the geothermal fluid 102 flows from the heat exchanger 26 to the one or more pumps 230. In some embodiments, the one or more pumps 230 are omitted. The geothermal fluid 102 flows from the heat exchanger 26 (via the one or more pumps 230, if present) to the turbocharger 210. The geothermal fluid 102 flows into the turbocharger 210 at the second inlet 222, and exits the turbocharger 210 at the second outlet 224. The turbocharger 210 utilizes the pressurePATENTAttorney Docket No.: SGEO / 0020PC of the relatively hotter geothermal fluid 102 at the first inlet 212 to increase the pressure of the relatively colder geothermal fluid 102 that enters the turbocharger 210 at the second inlet 222. The pressure of the geothermal fluid 102 is increased as the geothermal fluid 102 transits through the turbocharger 210 from the second inlet 222 to the second outlet 224 along the second fluid path 226. In an example, the pressure of the geothermal fluid 102 at the second outlet 224 is at or about 3 MPa or higher, such as 5 MPa or higher, 10 MPa or higher, 20 MPa or higher, 30 MPa or higher, 40 MPa or higher, or 50 MPa or higher. In some embodiments, the pressure of the geothermal fluid 102 at the second outlet 224 is less than the pressure of the geothermal fluid 102 at the first inlet 212. The temperature of the geothermal fluid 102 remains at or near the reduced level as the geothermal fluid 102 transits through the turbocharger 210 from the second inlet 222 to the second outlet 224 along the second fluid path 226.

[0145] The geothermal fluid 102 flows from the turbocharger 210 to the turbocharger 410. The geothermal fluid 102 flows into the turbocharger 410 at the first inlet 412, and exits the turbocharger 410 at the first outlet 414. The pressure of the geothermal fluid 102 is reduced as the geothermal fluid 102 transits through the turbocharger 410 from the first inlet 412 to the first outlet 414 along the first fluid path 416. In an example, the pressure of the geothermal fluid 102 at the first outlet 414 is at or about 1 MPa or less, such as 0.5 MPa or less, 0.4 MPa or less, 0.3 MPa or less, or 0.2 MPa or less. The temperature of the geothermal fluid 102 at the first inlet 412 is at or near the temperature of the geothermal fluid 102 at the second outlet 224 of the turbocharger 210. The temperature of the geothermal fluid 102 at the first outlet 414 of the turbocharger 410 is at or near the temperature of the geothermal fluid 102 at the first inlet 412 of the turbocharger 410.

[0146] The turbocharger 410 forms part of the power fluid circuit 440, as described above. The power fluid 442 of the power fluid circuit 440 flows into the turbocharger 410 at the second inlet 422, and exits the turbocharger 410 at the second outlet 424. The turbocharger 410 utilizes the pressure of the geothermal fluid 102 at the first inlet 412 to increase the pressure of the power fluid 442. The pressure of the power fluid 442 is increased as the power fluid 442 transits through the turbocharger 410 from thePATENTAttorney Docket No.: SGEO / 0020PC second inlet 422 to the second outlet 424 along the second fluid path 426. In an example, the pressure of the power fluid 442 at the second outlet 424 is at or about 3 MPa or higher, such as 5 MPa or higher, 10 MPa or higher, 20 MPa or higher, 30 MPa or higher, 40 MPa or higher, or 50 MPa or higher. In some embodiments, the pressure of the power fluid 442 at the second outlet 424 is less than the pressure of the geothermal fluid 102 at the first inlet 412.

[0147] The power fluid 442 flows from the turbocharger 410 to the one or more turbines 444. In some embodiments, the one or more turbines 444 are located at the earth’s surface 40. In some embodiments, the one or more turbines 444 include a plurality of turbines 444 arranged in a series configuration such that the power fluid 442 flows to a first turbine 444 and then to a second turbine 444. In some embodiments, the one or more turbines 444 include a plurality of turbines 444 arranged in a parallel configuration. In an example, a first portion of the power fluid 442 flows to a first turbine 444, and a different second portion of the power fluid 442 flows simultaneously to a second turbine 444. In another example, one of the first or second turbines 444 is offline (such as for maintenance), and the power fluid 442 flows to the other of the first or second turbines 444.

[0148] In some embodiments, the power fluid 442 enters each turbine 444 at a temperature that is substantially equal to the temperature of the power fluid 442 at the second outlet 424 of the turbocharger 410. In an example, the temperature of the power fluid 442 at each turbine 444 is within 10 degrees C, such as within 7 degrees C, within 5 degrees C, or within 2 degrees C, of the temperature of the power fluid 442 at the second outlet 424 of the turbocharger 410. In some embodiments, the power fluid 442 does not flow through a heat exchanger between the second outlet 424 of the turbocharger 410 and the one or more turbines 444.

[0149] Each turbine 444 drives the corresponding shaft 446, which drives the corresponding generator 448 to produce electricity, as described above. The power fluid 442 experiences a drop in pressure as the power fluid 442 drives each turbine 444 to rotate the corresponding shaft 446, and drive the corresponding generator 448 to produce electricity. In an example, the pressure of the power fluid 442 exiting each turbine 444 is at or about 1 MPa or less, such as 0.5 MPa or less, 0.4 MPa or less, 0.3PATENTAttorney Docket No.: SGEO / 0020PCMPa or less, or 0.2 MPa or less. The power fluid 442 flows from each of the one or more turbines 444 to the second inlet 422 of the turbocharger 410.

[0150] In some embodiments, the power fluid 442 enters the second inlet 422 of the turbocharger 410 at a temperature that is substantially equal to the temperature of the power fluid 442 exiting each of the one or more turbines 444. In an example, the temperature of the power fluid 442 at the second inlet 422 of the turbocharger 410 is within 10 degrees C, such as within 7 degrees C, within 5 degrees C, or within 2 degrees C, of the temperature of the power fluid 442 exiting each of the one or more turbines 444. In some embodiments, the power fluid 442 does not flow through a heat exchanger between each of the one or more turbines 444 and the second inlet 422 of the turbocharger 410.

[0151] The geothermal fluid 102 flows from the first outlet 414 of the turbocharger 410 to the one or more pumps 434. The one or more pumps 434 increase a pressure of the geothermal fluid 102, and inject the geothermal fluid 102 into the second well 46. In some embodiments, the geothermal fluid 102 flows from the first outlet 414 of the turbocharger 410 to the reservoir 430 before flowing to the one or more pumps 434.

[0152] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 45 of the first well 44 is maintained at a magnitude such that the one or more fractures 62 remain open while the one or more pumps 434 pump the geothermal fluid 102 into the second well 46. In an example, the flow of the geothermal fluid 102 out of the first well 44 is choked by the valve 52. In another example, the turbocharger 210 is operated such that a back-pressure is exerted on the geothermal fluid 102 at the wellhead 45 of the first well 44.

[0153] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 is maintained at a magnitude such that the one or more fractures 64 remain open. In an example, the one or more pumps 434 are operated to maintain the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 at a magnitude such that the one or more fractures 64 remain open.PATENTAttorney Docket No.: SGEO / 0020PC

[0154] In some embodiments, the one or more fractures 62 intersect with the one or more fractures 64. In some embodiments, the one or more fractures 62 are contiguous with the one or more fractures 64. In some embodiments, the geothermal fluid 102 flows within the subterranean formation 42 from the second well 46 to the first well 44, and is produced again from the first well 44.

[0155] As illustrated, in some embodiments, the geothermal fluid 102 does not flow within the subterranean formation 42 from the second well 46 to the first well 44. In an example, the one or more fractures 62 do not intersect with the one or more fractures 64. In another example, the one or more fractures 62 are not contiguous with the one or more fractures 64. In such embodiments, the geothermal power system 400 is reconfigured to flow the geothermal fluid 102 from the second well 46 to the turbocharger 210, and to flow the returning geothermal fluid 102 from the one or more pumps 434 to the first well 44. In an example, the geothermal power system 500 includes the manifold assembly 150, described above. When the geothermal power system 500 includes the manifold assembly 150, line 162 fluidically couples the production manifold 160 with the turbocharger 210. The manifold assembly 150, first well 44, second well 46, third well (if present), and fourth well (if present) are operated as described above.

[0156] Additionally, or alternatively, the geothermal power system 500 is coupled to the well 70, as described above. In such embodiments, the well 70 is operated as described above when coupled to the geothermal power system 500.

[0157] Additionally, or alternatively, the first well 44 is coupled to the geothermal power system 500 via the flowline assembly 190 (Figure 1 D), such as described above. In such embodiments, the first well 44 is operated as described above when coupled to the geothermal power system 500 via the flowline assembly 190. The geothermal fluid 102 produced from the subterranean formation 42 via the first well 44 flows through line 192 to the turbocharger 210. The geothermal fluid 102 flows from the one or more pumps 434 through line 194 back to the first well 44, and is reinjected into the subterranean formation 42. When geothermal fluid 102 is flowing from the first well 44 to the turbocharger 210, valve 196 in line 192 is open, and valve 198 in line 194 is closed. When geothermal fluid 102 is flowing from the one or more pumpsPATENTAttorney Docket No.: SGEO / 0020PC434 to the first well 44, valve 198 in line 194 is open, and valve 196 in line 192 is closed.

[0158] In some embodiments, the first well 44 and the geothermal power system 500 are operated in a repeating alternating sequence of production of the geothermal fluid 102 from the subterranean formation 42, then reinjection of the geothermal fluid 102 into the subterranean formation 42 (“huff-and-puff”), such as described above. In examples of such embodiments, the geothermal fluid 102 is produced from the subterranean formation 42 via the first well 44, and utilized (as described above) in the geothermal power system 500. The geothermal fluid 102 is then stored in the reservoir 430. Then the flow of the geothermal fluid 102 from the first well 44 is ceased. Valve 196 of the flowline assembly 190 is closed, and valve 198 of the flowline assembly 190 is opened. Then the one or more pumps 434 pump the geothermal fluid 102 from the reservoir 430 back into the first well 44, and inject the geothermal fluid 102 into the subterranean formation 42. Valve 198 of the flowline assembly 190 is closed, and valve 196 of the flowline assembly 190 is opened. Then the sequence is repeated. In some embodiments, a time delay is implemented while the first well 44 is closed-in to allow the geothermal fluid 102 in the subterranean formation 42 (such as in the one or more fractures 62) to become heated by the subterranean formation 42 before reopening the first well 44.

[0159] Figure 6 schematically illustrates a geothermal power system 600. The geothermal power system 600 includes a binary cycle power plant 10B that utilizes the working fluid 12, as described above. Binary cycle power plant 10B is similar to binary cycle power plant 10 described above, except that the working fluid 12 passes through a turbocharger 610 before passing through the heat exchanger 26 during a cycle.

[0160] The geothermal power system 600 utilizes the geothermal fluid 102 described above. In some embodiments, the working fluid 12 in the binary cycle power plant 10B is segregated from the geothermal fluid 102. In some embodiments, the working fluid 12 may include at least a portion of the geothermal fluid 102. In some embodiments, the geothermal fluid 102 may include at least a portion of the working fluid 12.PATENTAttorney Docket No.: SGEO / 0020PC

[0161] The geothermal fluid 102 is heated, or is maintained at an elevated temperature, by the subterranean formation 42. In an example, the temperature of the geothermal fluid 102 is at or about 150 degrees C or higher, such as 175 degrees C or higher, 200 degrees C or higher, 250 degrees C or higher, or 300 degrees C or higher. The geothermal fluid 102 is maintained at an elevated pressure in the subterranean formation 42. In an example, the pressure of the geothermal fluid 102 in the subterranean formation 42 is at or about 3 MPa or higher, such as 5 MPa or higher, 10 MPa or higher, 20 MPa or higher, 30 MPa or higher, 40 MPa or higher, or 50 MPa or higher. In some embodiments, the geothermal fluid 102 is geopressured. In an example, the geothermal fluid 102 may be a geopressured-geothermal fluid.

[0162] The geothermal fluid 102 flows from the subterranean formation 42 into the first well 44. In some embodiments, the geothermal fluid 102 flows from the subterranean formation 42 into the first well 44 via one or more fractures 62 in the subterranean formation 42 at the first well 44. In some embodiments, the temperature of the geothermal fluid 102 at the wellhead 45 of the first well 44 is at or near the temperature of the geothermal fluid 102 in the subterranean formation 42.

[0163] The geothermal fluid 102 flows from the first well 44 to a turbocharger 610. Any of turbocharger 800A, 800B, 800C, or 800D (all described below) may be used as turbocharger 610. In some embodiments, the geothermal power system 600 includes a plurality of turbochargers 610, such as in a parallel hookup configuration.

[0164] The geothermal fluid 102 flows through the turbocharger 610 and then through the heat exchanger 26. The working fluid 12 flows through the turbocharger 610 and then through the heat exchanger 26. The geothermal fluid 102 and the working fluid 12 flow simultaneously through the turbocharger 610 and then through the heat exchanger 26.

[0165] The geothermal fluid 102 flows into the turbocharger 610 at a first inlet 612, and exits the turbocharger 610 at a first outlet 614. The pressure of the geothermal fluid 102 is reduced as the geothermal fluid 102 transits through the turbocharger 610 from the first inlet 612 to the first outlet 614 along a first fluid path 616. In an example, the pressure of the geothermal fluid 102 at the first outlet 314 is at or about 20 MPa orPATENTAttorney Docket No.: SGEO / 0020PC less, such as 15 MPa or less, 10 MPa or less, 5 MPa or less, 3 MPa or less, 1 MPa or less, 0.5 MPa or less, or 0.2 MPa or less. The temperature of the geothermal fluid 102 at the first inlet 612 is at or near the temperature of the geothermal fluid 102 at the wellhead 45 of the first well 44. The temperature of the geothermal fluid 102 at the first outlet 614 is at or near the temperature of the geothermal fluid 102 at the first inlet 612.

[0166] The working fluid 12 flows into the turbocharger 610 at a second inlet 622, and exits the turbocharger 610 at a second outlet 624. The turbocharger 610 utilizes the pressure of the geothermal fluid 102 at the first inlet 612 to increase the pressure of the working fluid 12. The pressure of the working fluid 12 is increased as the working fluid 12 transits through the turbocharger 610 from the second inlet 622 to the second outlet 624 along a second fluid path 626. The second fluid path 626 is separate from the first fluid path 616. In an example, the pressure of the working fluid 12 at the second outlet 624 is at or about 5 MPa or higher, such as 7.5 MPa or higher, 10 MPa or higher, 12.5 MPa or higher, or 15 MPa or higher.

[0167] The geothermal fluid 102 flows from the first outlet 614 of the turbocharger 610 to the heat exchanger 26. In some embodiments, the temperature of the geothermal fluid 102 entering the heat exchanger 26 is similar to the temperature of the geothermal fluid 102 at the first outlet 614, such as at or near the temperature of the geothermal fluid 102 at the first inlet 612 or at the first well 44. In an example, the geothermal fluid 102 is at or about 150 degrees C or higher, such as 175 degrees C or higher, 200 degrees C or higher, 250 degrees C or higher, or 300 degrees C or higher when entering the heat exchanger 26.

[0168] The working fluid 12 flows from the second outlet 624 of the turbocharger 610 to the heat exchanger 26. Heat is transferred from the geothermal fluid 102 to the working fluid 12 as the geothermal fluid 102 and the working fluid 12 flow through the heat exchanger 26. The temperature of the geothermal fluid 102 is lowered to a reduced level as the geothermal fluid 102 flows through the heat exchanger 26. In an example, the temperature of the geothermal fluid 102 upon exiting the heat exchanger 26 is at or about 100 degrees C or less, such as 90 degrees C or less, 80 degrees C or less, 70 degrees C or less, 60 degrees C or less, or 50 degrees C or less. In anPATENTAttorney Docket No.: SGEO / 0020PC example, at the heat exchanger 26, the temperature of the working fluid 12 is increased to 100 degrees C or higher, such as 125 degrees C or higher, 150 degrees C or higher, 175 degrees C or higher, or 200 degrees C or higher.

[0169] The working fluid 12 flows from the heat exchanger 26 to the expander 30. The working fluid 12 loses heat and pressure as the working fluid 12 drives the expander 30 and the associated generator 36 to generate electricity. For example, the pressure of the working fluid 12 exiting the expander 30 may be at or about 5 MPa or lower, such as 4 MPa or lower, 3 MPa or lower, 2 MPa or lower, 1 MPa or lower, or 0.5 MPa or lower. Additionally, the temperature of the working fluid 12 exiting the expander 30 may be at or about 100 degrees C or less, such as 90 degrees C or less, 80 degrees C or less, 70 degrees C or less, 60 degrees C or less, or 50 degrees C or less.

[0170] The working fluid 12 flows from the expander 30 through the recuperator 24 and the condenser 20, as described above. The working fluid 12 flows from the condenser 20 to a pressure booster, such as pressure booster 22 (Figure 1A). In some embodiments, in binary cycle power plant 10B, the pressure booster 22 is replaced by pressure booster 22B. The pressure booster 22B may be any kind of pressure booster, such as a pump (e.g. a single phase pump, a multi-phase pump, a centrifugal pump, or a positive displacement pump), a compressor, or the like. The pressure booster 22B may be sized to provide a smaller pressure boost to the working fluid 12 than would be provided by the pressure booster 22.

[0171] The pressure booster 22B increases the pressure of the working fluid 12, and moves the working fluid 12 through the recuperator 24 to the turbocharger 610. In some embodiments, the turbocharger 610 and the pressure booster 22B provide a substantially equal amount of the boost in pressure to the working fluid 12 after the working fluid 12 exits the condenser 20 prior to entering the expander 30. In some embodiments, the pressure booster 22B provides a majority of the boost in pressure to the working fluid 12 after the working fluid 12 exits the condenser 20 prior to entering the expander 30. In some embodiments, the turbocharger 610 provides a majority of the boost in pressure to the working fluid 12 after the working fluid 12 exits the condenser 20 prior to entering the expander 30. In some embodiments, the pressurePATENTAttorney Docket No.: SGEO / 0020PC booster 22B is omitted, and the turbocharger 610 provides an entirety of the boost in pressure to the working fluid 12 after the working fluid 12 exits the condenser 20 prior to entering the expander 30.

[0172] In some embodiments, at least a portion of the working fluid 12 is diverted from another portion of the working fluid 12 prior to entering the turbocharger 610. The diverted portion of the working fluid 12 passes through a second turbocharger (not shown) that is driven by a pressurized boost fluid, such as a portion of the geothermal fluid 102. A pressure of the diverted portion of the working fluid 12 is increased in the second turbocharger. Any of turbocharger 800A, 800B, 800C, or 800D (all described below) may be used as the second turbocharger.

[0173] The diverted portion of the working fluid 12 with the now increased pressure is then recombined with the remainder of the working fluid 12 before the working fluid 12 enters the turbocharger 610. Such an arrangement may act as a surge dampener to help reduce any pressure fluctuations in the flow rate or pressure of the geothermal fluid 102 that may in turn be reflected in fluctuations in the flow rate or pressure of the working fluid 12 during operation of the turbocharger 610. In this way, the expander 30 receives the working fluid 12 at a flow rate and a pressure that are relatively more stable than would otherwise be the case.

[0174] In some embodiments, the second turbocharger is omitted.

[0175] As described above, the geothermal power system 600 transfers heat energy and pressure energy of the geothermal fluid 102 to the working fluid 12 of the binary cycle power plant 10B. The binary cycle power plant 10B converts the transferred heat energy and pressure energy into electricity.

[0176] Turning back to the flow of the geothermal fluid 102, the geothermal fluid 102 flows from the heat exchanger 26 to one or more pumps 634. Exemplary pumps 634 include single phase pumps, multi-phase pumps, centrifugal pumps, positive displacement pumps, or the like. The one or more pumps 634 increase a pressure of the geothermal fluid 102, and inject the geothermal fluid 102 into the second well 46. The geothermal fluid 102 flows through the second well 46, and enters the one or more fractures 64 in the subterranean formation 42.PATENTAttorney Docket No.: SGEO / 0020PC

[0177] In some embodiments, the geothermal fluid 102 flows from the heat exchanger 26 to a reservoir 632 (such as a pond, a tank, or a subterranean formation different from subterranean formation 42), before flowing to the one or more pumps 634. In some embodiments, the reservoir 632 provides for temporary storage of the geothermal fluid 102 prior to injecting the geothermal fluid 102 into the second well 46. In an example, the geothermal fluid 102 is utilized in the geothermal power system 600 to produce electricity and is stored in reservoir 632 during a period of relatively high demand for electricity, then is injected into the second well 46 during a subsequent period of relatively low demand for electricity. In some embodiments, the reservoir 632 is omitted.

[0178] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 45 of the first well 44 is maintained at a magnitude such that the one or more fractures 62 remain open while flowing the geothermal fluid 102 to the turbocharger 610. In an example, the flow of the geothermal fluid 102 out of the first well 44 is choked by valve 52. In another example, the turbocharger 610 is operated such that a back-pressure is exerted on the geothermal fluid 102 at the wellhead 45 of the first well 44.

[0179] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 is maintained at a magnitude such that the one or more fractures 64 remain open. In an example, the one or more pumps 634 are operated to maintain the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 at a magnitude such that the one or more fractures 64 remain open.

[0180] In some embodiments, the one or more fractures 62 intersect with the one or more fractures 64. In some embodiments, the one or more fractures 62 are contiguous with the one or more fractures 64. In some embodiments, the geothermal fluid 102 flows within the subterranean formation 42 from the second well 46 to the first well 44, and is produced again from the first well 44.

[0181] As illustrated, in some embodiments, the geothermal fluid 102 does not flow within the subterranean formation 42 from the second well 46 to the first well 44. In an example, the one or more fractures 62 do not intersect with the one or morePATENTAttorney Docket No.: SGEO / 0020PC fractures 64. In another example, the one or more fractures 62 are not contiguous with the one or more fractures 64. In such embodiments, the geothermal power system 600 is reconfigured to flow the geothermal fluid 102 from the second well 46 to the turbocharger 610, and to flow the returning geothermal fluid 102 from the one or more pumps 634 to the first well 44. In an example, the geothermal power system 300 includes the manifold assembly 150, described above.

[0182] When the geothermal power system 600 includes the manifold assembly 150, line 162 fluidically couples the production manifold 160 with the turbocharger 610. When the geothermal power system 600 includes the manifold assembly 150, line 172 fluidically couples the one or more pumps 634 to the injection manifold 170. The manifold assembly 150, first well 44, second well 46, third well (if present), and fourth well (if present) are operated as described above.

[0183] Additionally, or alternatively, the geothermal power system 600 is coupled to the well 70, as described above. In such embodiments, the well 70 is operated as described above when coupled to the geothermal power system 600. The geothermal fluid 102 produced from the subterranean formation 42 at the production zone 72 flows up the tubing string 76 to the wellhead 71 , and from the wellhead 71 to the turbocharger 610. The geothermal fluid 102 flows from the one or more pumps 634 into the annulus 80, and into the subterranean formation 42 at the injection zone 74.

[0184] Additionally, or alternatively, the first well 44 is coupled to the geothermal power system 600 via the flowline assembly 190 (Figure 1 D), such as described above. In such embodiments, the first well 44 is operated as described above when coupled to the geothermal power system 600 via the flowline assembly 190. The geothermal fluid 102 produced from the subterranean formation 42 via the first well 44 flows through line 192 to the turbocharger 610. The geothermal fluid 102 flows from the one or more pumps 634 through line 194 back to the first well 44, and is reinjected into the subterranean formation 42. When geothermal fluid 102 is flowing from the first well 44 to the turbocharger 610, valve 196 in line 192 is open, and valve 198 in line 194 is closed. When geothermal fluid 102 is flowing from the one or more pumps 634 to the first well 44, valve 198 in line 194 is open, and valve 196 in line 192 is closed. In some embodiments, the first well 44 and the geothermal power system 600PATENTAttorney Docket No.: SGEO / 0020PC are operated in a repeating alternating sequence of production of the geothermal fluid 102 from the subterranean formation 42, then reinjection of the geothermal fluid 102 into the subterranean formation 42 (“huff-and-puff”), such as described above.

[0185] Figure 7 schematically illustrates a geothermal power system 700. The geothermal power system 700 includes a binary cycle power plant 10C that utilizes the working fluid 12, as described above. Binary cycle power plant 10C is similar to binary cycle power plant 10 described above, except that after passing through the heat exchanger 26, the working fluid 12 passes through a turbocharger 710 before entering the expander 30.

[0186] The geothermal power system 700 utilizes the geothermal fluid 102 described above. In some embodiments, the working fluid 12 in the binary cycle power plant 10C is segregated from the geothermal fluid 102. In some embodiments, the working fluid 12 may include at least a portion of the geothermal fluid 102. In some embodiments, the geothermal fluid 102 may include at least a portion of the working fluid 12.

[0187] The geothermal fluid 102 is heated, or is maintained at an elevated temperature, by the subterranean formation 42. In an example, the temperature of the geothermal fluid 102 is at or about 150 degrees C or higher, such as 175 degrees C or higher, 200 degrees C or higher, 250 degrees C or higher, or 300 degrees C or higher. The geothermal fluid 102 is maintained at an elevated pressure in the subterranean formation 42. In an example, the pressure of the geothermal fluid 102 in the subterranean formation 42 is at or about 3 MPa or higher, such as 5 MPa or higher, 10 MPa or higher, 20 MPa or higher, 30 MPa or higher, 40 MPa or higher, or 50 MPa or higher. In some embodiments, the geothermal fluid 102 is geopressured. In an example, the geothermal fluid 102 may be a geopressured-geothermal fluid.

[0188] The geothermal fluid 102 flows from the subterranean formation 42 into the first well 44. In some embodiments, the geothermal fluid 102 flows from the subterranean formation 42 into the first well 44 via one or more fractures 62 in the subterranean formation 42 at the first well 44. In some embodiments, the temperaturePATENTAttorney Docket No.: SGEO / 0020PC of the geothermal fluid 102 at the wellhead 45 of the first well 44 is at or near the temperature of the geothermal fluid 102 in the subterranean formation 42.

[0189] The geothermal fluid 102 flows from the first well 44 to the heat exchanger 26. In some embodiments, the temperature of the geothermal fluid 102 entering the heat exchanger 26 is similar to the temperature of the geothermal fluid 102 at the first well 44. In an example, the geothermal fluid 102 is at or about 150 degrees C or higher, such as 175 degrees C or higher, 200 degrees C or higher, 250 degrees C or higher, or 300 degrees C or higher when entering the heat exchanger 26.

[0190] The working fluid 12 flows from the recuperator 24 to the heat exchanger 26. Heat is transferred from the geothermal fluid 102 to the working fluid 12 as the geothermal fluid 102 and the working fluid 12 flow through the heat exchanger 26. The temperature of the geothermal fluid 102 is lowered to a reduced level as the geothermal fluid 102 flows through the heat exchanger 26. In an example, the temperature of the geothermal fluid 102 upon exiting the heat exchanger 26 is at or about 100 degrees C or less, such as 90 degrees C or less, 80 degrees C or less, 70 degrees C or less, 60 degrees C or less, or 50 degrees C or less. In an example, at the heat exchanger 26, the temperature of the working fluid 12 is increased to 100 degrees C or higher, such as 125 degrees C or higher, 150 degrees C or higher, 175 degrees C or higher, or 200 degrees C or higher.

[0191] The geothermal fluid 102 flows through the heat exchanger 26 and then through the turbocharger 710. The working fluid 12 flows through the heat exchanger 26 and then through the turbocharger 710. The geothermal fluid 102 and the working fluid 12 flow simultaneously through the heat exchanger 26 and then through the turbocharger 710. Any of turbocharger 800A, 800B, 800C, or 800D (all described below) may be used as turbocharger 710. In some embodiments, the geothermal power system 700 includes a plurality of turbochargers 710, such as in a parallel hookup configuration.

[0192] The geothermal fluid 102 flows into the turbocharger 710 at a first inlet 712, and exits the turbocharger 710 at a first outlet 714. The pressure of the geothermal fluid 102 is reduced as the geothermal fluid 102 transits through the turbocharger 710PATENTAttorney Docket No.: SGEO / 0020PC from the first inlet 712 to the first outlet 714 along a first fluid path 716. In an example, the pressure of the geothermal fluid 102 at the first outlet 714 is at or about 20 MPa or less, such as 15 MPa or less, 10 MPa or less, 5 MPa or less, 3 MPa or less, 1 MPa or less, 0.5 MPa or less, or 0.2 MPa or less. The temperature of the geothermal fluid 102 at the first inlet 712 is at or near the temperature of the geothermal fluid exiting the heat exchanger 26. The temperature of the geothermal fluid 102 at the first outlet 714 is at or near the temperature of the geothermal fluid 102 at the first inlet 712.

[0193] The working fluid 12 flows into the turbocharger 710 at a second inlet 722, and exits the turbocharger 710 at a second outlet 724. The turbocharger 710 utilizes the pressure of the geothermal fluid 102 at the first inlet 712 to increase the pressure of the working fluid 12. The pressure of the working fluid 12 is increased as the working fluid 12 transits through the turbocharger 710 from the second inlet 722 to the second outlet 724 along a second fluid path 726. The second fluid path 726 is separate from the first fluid path 716. In an example, the pressure of the working fluid 12 at the second outlet 724 is at or about 5 MPa or higher, such as 7.5 MPa or higher, 10 MPa or higher, 12.5 MPa or higher, or 15 MPa or higher.

[0194] In some embodiments, the temperature of the working fluid 12 at the second outlet 724 is at or near the temperature of the working fluid 12 at the second inlet 722 of the turbocharger 710. In some embodiments, the temperature of the working fluid 12 at the second outlet 724 is at or near the temperature of the working fluid 12 exiting the heat exchanger 26.

[0195] The working fluid 12 flows from the turbocharger 710 to the expander 30. The working fluid 12 loses heat and pressure as the working fluid 12 drives the expander 30 and the associated generator 36 to generate electricity. For example, the pressure of the working fluid 12 exiting the expander 30 may be at or about 5 MPa or lower, such as 4 MPa or lower, 3 MPa or lower, 2 MPa or lower, 1 MPa or lower, or 0.5 MPa or lower. Additionally, the temperature of the working fluid 12 exiting the expander 30 may be at or about 100 degrees C or less, such as 90 degrees C or less, 80 degrees C or less, 70 degrees C or less, 60 degrees C or less, or 50 degrees C or less.PATENTAttorney Docket No.: SGEO / 0020PC

[0196] The working fluid 12 flows from the expander 30 through the recuperator 24 and the condenser 20, as described above. The working fluid 12 flows from the condenser 20 to a pressure booster, such as pressure booster 22 (Figure 1A). In some embodiments, in binary cycle power plant 10C, the pressure booster 22 is replaced by pressure booster 22C. The pressure booster 22C may be any kind of pressure booster, such as a pump (e.g. a single phase pump, a multi-phase pump, a centrifugal pump, or a positive displacement pump), a compressor, or the like. The pressure booster 22C may be sized to provide a smaller pressure boost to the working fluid 12 than would be provided by the pressure booster 22.

[0197] The pressure booster 22C increases the pressure of the working fluid 12, and moves the working fluid 12 through the recuperator 24 to the heat exchanger 26, where the working fluid 12 is heated, as described above. In some embodiments, the turbocharger 710 and the pressure booster 22C provide a substantially equal amount of the boost in pressure to the working fluid 12 after the working fluid 12 exits the condenser 20 prior to entering the expander 30. In some embodiments, the pressure booster 22C provides a majority of the boost in pressure to the working fluid 12 after the working fluid 12 exits the condenser 20 prior to entering the expander 30. In some embodiments, the turbocharger 710 provides a majority of the boost in pressure to the working fluid 12 after the working fluid 12 exits the condenser 20 prior to entering the expander 30. In some embodiments, the pressure booster 22C is omitted, and the turbocharger 710 provides an entirety of the boost in pressure to the working fluid 12 after the working fluid 12 exits the condenser 20 prior to entering the expander 30.

[0198] In some embodiments, at least a portion of the working fluid 12 is diverted from another portion of the working fluid 12 prior to entering the turbocharger 710. The diverted portion of the working fluid 12 passes through a second turbocharger (not shown) that is driven by a pressurized boost fluid, such as a portion of the geothermal fluid 102. A pressure of the diverted portion of the working fluid 12 is increased in the second turbocharger. Any of turbocharger 800A, 800B, 800C, or 800D (all described below) may be used as the second turbocharger.

[0199] The diverted portion of the working fluid 12 with the now increased pressure is then recombined with the remainder of the working fluid 12 before the working fluidPATENTAttorney Docket No.: SGEO / 0020PC12 enters the turbocharger 710. Such an arrangement may act as a surge dampener to help reduce any pressure fluctuations in the flow rate or pressure of the geothermal fluid 102 that may in turn be reflected in fluctuations in the flow rate or pressure of the working fluid 12 during operation of the turbocharger 710. In this way, the expander 30 receives the working fluid 12 at a flow rate and a pressure that are relatively more stable than would otherwise be the case.

[0200] In some embodiments, the second turbocharger is omitted.

[0201] As described above, the geothermal power system 700 transfers heat energy and pressure energy of the geothermal fluid 102 to the working fluid 12 of the binary cycle power plant 10C. The binary cycle power plant 10C converts the transferred heat energy and pressure energy into electricity.

[0202] Turning back to the flow of the geothermal fluid 102, the geothermal fluid 102 flows from the first outlet 714 of the turbocharger 710 to one or more pumps 734. Exemplary pumps 734 include single phase pumps, multi-phase pumps, centrifugal pumps, positive displacement pumps, or the like. The one or more pumps 734 increase a pressure of the geothermal fluid 102, and inject the geothermal fluid 102 into the second well 46. The geothermal fluid 102 flows through the second well 46, and enters the one or more fractures 64 in the subterranean formation 42.

[0203] In some embodiments, the geothermal fluid 102 flows from the turbocharger 710 to a reservoir 732 (such as a pond, a tank, or a subterranean formation different from subterranean formation 42), before flowing to the one or more pumps 734. In some embodiments, the reservoir 732 provides for temporary storage of the geothermal fluid 102 prior to injecting the geothermal fluid 102 into the second well 46. In an example, the geothermal fluid 102 is utilized in the geothermal power system 700 to produce electricity and is stored in reservoir 732 during a period of relatively high demand for electricity, then is injected into the second well 46 during a subsequent period of relatively low demand for electricity. In some embodiments, the reservoir 732 is omitted.

[0204] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 45 of the first well 44 is maintained at a magnitude such that the one or morePATENTAttorney Docket No.: SGEO / 0020PC fractures 62 remain open while flowing the geothermal fluid 102 to the heat exchanger 26. In an example, the flow of the geothermal fluid 102 out of the first well 44 is choked by valve 52. In another example, the heat exchanger 26 and the turbocharger 710 downstream of the heat exchanger 26 are operated such that a back-pressure is exerted on the geothermal fluid 102 at the wellhead 45 of the first well 44.

[0205] In some embodiments, the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 is maintained at a magnitude such that the one or more fractures 64 remain open. In an example, the one or more pumps 734 are operated to maintain the pressure of the geothermal fluid 102 at the wellhead 47 of the second well 46 at a magnitude such that the one or more fractures 64 remain open.

[0206] In some embodiments, the one or more fractures 62 intersect with the one or more fractures 64. In some embodiments, the one or more fractures 62 are contiguous with the one or more fractures 64. In some embodiments, the geothermal fluid 102 flows within the subterranean formation 42 from the second well 46 to the first well 44, and is produced again from the first well 44.

[0207] As illustrated, in some embodiments, the geothermal fluid 102 does not flow within the subterranean formation 42 from the second well 46 to the first well 44. In an example, the one or more fractures 62 do not intersect with the one or more fractures 64. In another example, the one or more fractures 62 are not contiguous with the one or more fractures 64. In such embodiments, the geothermal power system 700 is reconfigured to flow the geothermal fluid 102 from the second well 46 to the heat exchanger 26, and to flow the returning geothermal fluid 102 from the one or more pumps 734 to the first well 44. In an example, the geothermal power system 700 includes the manifold assembly 150, described above.

[0208] When the geothermal power system 700 includes the manifold assembly 150, line 162 fluidically couples the production manifold 160 with the heat exchanger 26. When the geothermal power system 700 includes the manifold assembly 150, line 172 fluidically couples the one or more pumps 734 to the injection manifold 170. The manifold assembly 150, first well 44, second well 46, third well (if present), and fourth well (if present) are operated as described above.PATENTAttorney Docket No.: SGEO / 0020PC

[0209] Additionally, or alternatively, the geothermal power system 700 is coupled to the well 70, as described above. In such embodiments, the well 70 is operated as described above when coupled to the geothermal power system 700. The geothermal fluid 102 produced from the subterranean formation 42 at the production zone 72 flows up the tubing string 76 to the wellhead 71 , and from the wellhead 71 to the heat exchanger 26. The geothermal fluid 102 flows from the one or more pumps 734 into the annulus 80, and into the subterranean formation 42 at the injection zone 74.

[0210] Additionally, or alternatively, the first well 44 is coupled to the geothermal power system 700 via the flowline assembly 190 (Figure 1 D), such as described above. In such embodiments, the first well 44 is operated as described above when coupled to the geothermal power system 700 via the flowline assembly 190. The geothermal fluid 102 produced from the subterranean formation 42 via the first well 44 flows through line 192 to the heat exchanger 26. The geothermal fluid 102 flows from the one or more pumps 734 through line 194 back to the first well 44, and is reinjected into the subterranean formation 42. When geothermal fluid 102 is flowing from the first well 44 to the heat exchanger 26, valve 196 in line 192 is open, and valve 198 in line 194 is closed. When geothermal fluid 102 is flowing from the one or more pumps 734 to the first well 44, valve 198 in line 194 is open, and valve 196 in line 192 is closed. In some embodiments, the first well 44 and the geothermal power system 700 are operated in a repeating alternating sequence of production of the geothermal fluid 102 from the subterranean formation 42, then reinjection of the geothermal fluid 102 into the subterranean formation 42 (“huff-and-puff”), such as described above.

[0211] It is contemplated that any of the geothermal power systems 100, 200, 300, 400, 500, 600, or 700 may incorporate one or more elements of any other of the geothermal power systems 100, 200, 300, 400, 500, 600, or 700.

[0212] Figures 8A to 8D schematically illustrate embodiments of turbochargers that may be incorporated into any of the geothermal power systems 100, 200, 300, 400, 500, 600, or 700.PATENTAttorney Docket No.: SGEO / 0020PC

[0213] Figure 8A schematically illustrates turbocharger 800A. Turbocharger 800A includes a turbine 810 coupled to a pump 830. In some embodiments, turbocharger 800A is configured as a hydraulic turbocharger.

[0214] A first fluid is conveyed to the turbine 810 via a first input line 812. The first fluid enters the turbine 810 at a first inlet 814, and traverses via a first fluid path 816 to a first outlet 818. While traversing via the first fluid path 816, the first fluid interacts with a turbine impeller 822. In some examples, the turbine impeller 822 includes a plurality of blades or vanes, and the first fluid impinges on the plurality of blades or vanes, causing the turbine impeller 822 to rotate. A pressure of the first fluid at the first inlet 814 is greater than a pressure of the first fluid at the first outlet 818. The first fluid loses kinetic energy along the first fluid path 816 as the first fluid causes the turbine impeller 822 to rotate. The first fluid exits the turbine 810 at the first outlet 818 into a first output line 820.

[0215] In some embodiments, the pump 830 is configured as a centrifugal pump. In some embodiments, the pump 830 is configured as a centrifugal compressor. A second fluid is conveyed to the pump 830 via a second input line 832. The second fluid enters the pump 830 at a second inlet 834, and traverses via a second fluid path 836 to a second outlet 838. The second fluid exits the pump 830 at the second outlet 838 into a second output line 840. While traversing via the second fluid path 836, the second fluid interacts with a pump impeller 842. In some examples, the pump impeller 842 includes a plurality of blades or vanes.

[0216] The turbine impeller 822 is coupled to the pump impeller 842 by an output shaft 824. In the depicted embodiment, the output shaft 824 directly couples the turbine impeller 822 to the pump impeller 842. Rotation of the turbine impeller 822 causes rotation of the output shaft 824 and rotation of the pump impeller 842. In the depicted embodiment, the turbine impeller 822 and the pump impeller 842 rotate at the same speed. Rotation of the pump impeller 842 adds kinetic energy to the second fluid. In some embodiments, a pressure of the second fluid at the second outlet 838 is greater than a pressure of the second fluid at the second inlet 834. In some embodiments, a flow rate of the second fluid at the second outlet 838 is greater than a flow rate of the second fluid at the second inlet 834.PATENTAttorney Docket No.: SGEO / 0020PC

[0217] In some embodiments, the turbocharger 800A includes a bypass 850 that fluidically couples the first input line 812 with the first output line 820. In some examples, at least a portion of the first fluid is flowed through the bypass 850. In other examples, all the first fluid is flowed through the turbine 810, and no first fluid is flowed through the bypass 850. In some embodiments, the flow of first fluid through the bypass 850 is controlled by a control valve 852. In some examples, the control valve 852 regulates the flow of the first fluid through the bypass 850 from zero flow through the bypass 850 to 100% flow through the bypass 850.

[0218] In some embodiments, turbocharger 800A is used in processes in which the first fluid and the second fluid are similar fluids. In some embodiments, turbocharger 800A is used in processes in which the first fluid and the second fluid are not similar fluids.

[0219] Figure 8B schematically illustrates turbocharger 800B. Turbocharger 800B is similar to turbocharger 800A, except that the turbine impeller 822 and the pump impeller 842 can rotate at different speeds. The output shaft 824 of the turbine 810 is coupled to the pump impeller 842 via a gearbox 826. The gearbox 826 is coupled to the pump impeller 842 via an input shaft 844. Rotation of the output shaft 824 causes rotation of gears in the gearbox 826. Rotation of the gears in the gearbox 826 causes rotation of the input shaft 844, and rotation of the pump impeller 842.

[0220] In some embodiments, the turbine impeller 822 rotates faster than the pump impeller 842. In some embodiments, the turbine impeller 822 rotates slower than the pump impeller 842. In some embodiments, turbocharger 800B is used in processes in which the first fluid and the second fluid are similar fluids. In some embodiments, turbocharger 800A is used in processes in which the first fluid and the second fluid are not similar fluids.

[0221] Figure 8C schematically illustrates turbocharger 800C. Turbocharger 800C is similar to turbocharger 800A or 800B, except that an additional rotation drive is provided to the pump impeller 842. A motor 860 is coupled to the pump impeller 842, and provides a motive power to the pump impeller 842 additional to the motive power provided by the turbine impeller 822. The motor 860 drives a motor shaft 862. ThePATENTAttorney Docket No.: SGEO / 0020PC motor shaft 862 is coupled to the pump impeller 842 via a gearbox 864. The gearbox 864 is coupled to the pump impeller 842 via a second input shaft 846. Rotation of the motor shaft 862 by the motor 860 causes rotation of gears in the gearbox 864. Rotation of the gears in the gearbox 864 causes rotation of the second input shaft 846, and rotation of the pump impeller 842.

[0222] In some embodiments, the turbine 810 and the motor 860 are not operated simultaneously to rotate the pump impeller 842. In some embodiments, the turbine 810 and the motor 860 are operated simultaneously to rotate the pump impeller 842. In some embodiments, the turbine 810 provides more power than the motor 860 to rotate the pump impeller 842. In some embodiments, the turbine 810 provides less power than the motor 860 to rotate the pump impeller 842. In some embodiments, the turbine 810 and the motor 860 provide equal amounts of power to rotate the pump impeller 842.

[0223] As illustrated, in some embodiments, the turbine impeller 822 is coupled to the pump impeller 842 via the output shaft 824, gearbox 826, and the input shaft 844. However, in some embodiments, the gearbox 826 is omitted (such as in turbocharger 800A), and the turbine impeller 822 is directly coupled to the pump impeller 842 via the output shaft 824.

[0224] Figure 8D schematically illustrates turbocharger 800D. Turbocharger 800D is similar to turbocharger 800A or 800B, except that an additional rotation drive is provided to the turbine impeller 822, which is then transferred to the pump impeller 842. The motor 860 is coupled to the turbine impeller 822, and provides a motive power to the turbine impeller 822 additional to the motive power provided by the first fluid acting on the turbine impeller 822. The motor 860 drives the motor shaft 862, which is coupled to the turbine impeller 822 via the gearbox 864. The gearbox 864 is coupled to the turbine impeller 822 via an input shaft 828. Rotation of the motor shaft 862 by the motor 860 causes rotation of gears in the gearbox 864. Rotation of the gears in the gearbox 864 causes rotation of the input shaft 828, and rotation of the turbine impeller 822.PATENTAttorney Docket No.: SGEO / 0020PC

[0225] Rotation of the turbine impeller 822 causes rotation of the pump impeller 842, as described above with respect to turbocharger 800A or turbocharger 800B. As illustrated, in some embodiments, the turbine impeller 822 is coupled to the pump impeller 842 via the output shaft 824, gearbox 826, and the input shaft 844. However, in some embodiments, the gearbox 826 is omitted (such as in turbocharger 800A), and the turbine impeller 822 is directly coupled to the pump impeller 842 via the output shaft 824.

[0226] The turbine 810 and the motor 860 are operated simultaneously to rotate the pump impeller 842. In some embodiments, the turbine 810 provides more power than the motor 860 to rotate the pump impeller 842. In some embodiments, the turbine 810 provides less power than the motor 860 to rotate the pump impeller 842. In some embodiments, the turbine 810 and the motor 860 provide equal amounts of power to rotate the pump impeller 842.

[0227] Figure 9 is a flow diagram of a method 900 of operating a geothermal power system. The geothermal power system may be any of geothermal power system 100, 200, or 500.

[0228] Operation 902 includes flowing a first fluid into a first inlet of a first turbocharger. In some embodiments, the first fluid is a geothermal fluid, such as geothermal fluid 102. In some embodiments, the first fluid is produced from a subterranean formation, such as subterranean formation 42. In some embodiments, the first turbocharger is turbocharger 110 or 210.

[0229] Operation 904 includes flowing the first fluid from a first outlet of the first turbocharger to a heat exchanger. In some embodiments, method 900 includes reducing a pressure of the first fluid in the first turbocharger as the first fluid transits from the first inlet to the first outlet. In some embodiments, the heat exchanger is heat exchanger 26. In some embodiments, method 900 includes using heat of the first fluid to increase a temperature of a second fluid at the heat exchanger. In some embodiments, the second fluid is a working fluid, such as working fluid 12. In some embodiments, method 900 includes flowing the second fluid through an expander coupled to a generator, and generating electricity using the generator.PATENTAttorney Docket No.: SGEO / 0020PC

[0230] Operation 906 includes flowing the first fluid from the heat exchanger to a second inlet of the first turbocharger. In some embodiments, operation 906 includes pumping the first fluid from the heat exchanger to a second inlet of the first turbocharger.

[0231] Operation 908 includes discharging the first fluid from a second outlet of the first turbocharger. In some embodiments, operation 908 includes increasing a pressure of the first fluid in the first turbocharger as the first fluid transits from the second inlet to the second outlet.

[0232] In some embodiments, the first fluid transits from the first inlet of the first turbocharger to the first outlet of the first turbocharger in a first fluid path, and transits from the second inlet of the first turbocharger to the second outlet of the first turbocharger in a second fluid path separate from the first fluid path.

[0233] In some embodiments, method 900 includes flowing the first fluid into a first inlet of a second turbocharger (such as turbocharger 410). In some embodiments, flowing the first fluid into a first inlet of a second turbocharger occurs after discharging the first fluid from a second outlet of the first turbocharger. In some embodiments, method 900 includes reducing a pressure of the first fluid in the second turbocharger as the first fluid transits from the first inlet of the second turbocharger to a first outlet of the second turbocharger. In some embodiments, method 900 includes increasing a pressure of a second fluid in the second turbocharger as the second fluid transits from a second inlet of the second turbocharger to a second outlet of the second turbocharger. In some embodiments, the second fluid is a power fluid, such as power fluid 442. In some embodiments, method 900 includes flowing the second fluid through a turbine coupled to a generator, and generating electricity using the generator.

[0234] In some embodiments, method 900 includes producing the first fluid from a subterranean formation into a well, and flowing the first fluid from the well to the first turbocharger. In some embodiments, method 900 includes pumping the first fluid into the well, and injecting the first fluid back into the subterranean formation. In some embodiments, method 900 includes flowing the first fluid from the first turbocharger toPATENTAttorney Docket No.: SGEO / 0020PC a reservoir (such as reservoir 430) prior to pumping the first fluid into the well. In some embodiments, method 900 includes ceasing production of the first fluid from the well prior to pumping the first fluid into the well. In some embodiments, producing the first fluid from the subterranean formation comprises producing the first fluid from the subterranean formation at a first zone of the well, and injecting the first fluid back into the subterranean formation comprises injecting the first fluid into the subterranean formation at a second zone of the well, the second zone different from the first zone.

[0235] In some embodiments, method 900 includes producing the first fluid from a subterranean formation into a first well (such as first well 44), flowing the first fluid from the first well to the first turbocharger, and injecting the first fluid back into the subterranean formation via a second well (such as second well 46). In some embodiments, method 900 includes injecting additional geothermal fluid into the second well, the additional geothermal fluid being sourced from a reservoir (such as reservoir 240). In some embodiments, method 900 includes injecting the additional geothermal fluid into the second well using a charge pump (such as charge pump 242). In some embodiments, method 900 includes injecting the additional geothermal fluid into the second well using the charge pump to establish a selected operating pressure at a wellhead of the second well. The operating pressure at the wellhead of the second well may be selected such that one or more fractures in the subterranean formation coupled to the second well are open.

[0236] It is contemplated that method 900 may include any one or more of the operations or activities described herein.

[0237] Figure 10 is a flow diagram of a method 1000 of operating a geothermal power system, such as geothermal power system 100.

[0238] Operation 1002 includes flowing a first fluid into a first inlet of a turbocharger. In some embodiments, the first fluid is a geothermal fluid, such as geothermal fluid 102. In some embodiments, the first fluid is produced from a subterranean formation, such as subterranean formation 42. In some embodiments, the turbocharger is turbocharger 110.PATENTAttorney Docket No.: SGEO / 0020PC

[0239] Operation 1004 includes flowing the first fluid from a first outlet of the turbocharger to a heat exchanger. In some embodiments, method 1000 includes reducing a pressure of the first fluid in the turbocharger as the first fluid transits from the first inlet to the first outlet. In some embodiments, the heat exchanger is heat exchanger 26. In some embodiments, method 1000 includes using heat of the first fluid to increase a temperature of a second fluid at the heat exchanger. In some embodiments, the second fluid is a working fluid, such as working fluid 12. In some embodiments, method 1000 includes flowing the second fluid through an expander coupled to a generator, and generating electricity using the generator.

[0240] Operation 1006 includes flowing the first fluid from the heat exchanger to a second inlet of the turbocharger. In some embodiments, operation 1006 includes pumping the first fluid from the heat exchanger to the second inlet of the turbocharger.

[0241] Operation 1008 includes flowing the first fluid from a second outlet of the turbocharger to a turbine coupled to a generator. In some embodiments, the turbine is one of the one or more turbines 140. In some embodiments, the generator is generator 148.

[0242] In some embodiments, method 1000 includes increasing a pressure of the first fluid in the turbocharger as the first fluid transits from the second inlet to the second outlet. In some embodiments, the first fluid transits from the first inlet of the turbocharger to the first outlet of the first turbocharger in a first fluid path, and transits from the second inlet of the turbocharger to the second outlet of the turbocharger in a second fluid path separate from the first fluid path.

[0243] Operation 1010 includes generating electricity using the generator.

[0244] In some embodiments, method 1000 includes producing the first fluid from a subterranean formation into a well, and flowing the first fluid from the well to the turbocharger. In some embodiments, method 1000 includes flowing the first fluid from the turbine to a reservoir, such as reservoir 132. In some embodiments, method 1000 includes pumping the first fluid from the reservoir back into the subterranean formation at the well. In some embodiments, the well is configured similarly to first well 44. In some embodiments, the well is configured similarly to well 70.PATENTAttorney Docket No.: SGEO / 0020PC

[0245] In some embodiments, method 1000 includes producing the first fluid from a subterranean formation into a first well (such as first well 44), and flowing the first fluid from the well to the turbocharger. In some embodiments, method 1000 includes flowing the first fluid from the turbine to a second well (such as second well 46). In some embodiments, method 1000 includes injecting the first fluid into the subterranean formation at the second well.

[0246] It is contemplated that method 1000 may include any one or more of the operations or activities described herein.

[0247] Figure 11 is a flow diagram of a method 1100 of operating a geothermal power system, such as geothermal power system 300.

[0248] Operation 1102 includes simultaneously flowing a first fluid and a second fluid, such that the first fluid passes through a turbocharger and then through a heat exchanger, and the second fluid passes through the heat exchanger and then through the turbocharger. In some embodiments, the turbocharger is turbocharger 310. In some embodiments, the heat exchanger is heat exchanger 26.

[0249] In some embodiments, the first fluid is a geothermal fluid, such as geothermal fluid 102. In some embodiments, the first fluid is produced from a subterranean formation, such as subterranean formation 42. In some embodiments, the second fluid is a working fluid, such as working fluid 12.

[0250] Operation 1104 includes transferring heat from the first fluid to the second fluid at the heat exchanger.

[0251] Operation 1106 includes reducing a pressure of the first fluid at the turbocharger by increasing a pressure of the second fluid at the turbocharger. In some embodiments, the first fluid transits from a first inlet of the turbocharger to a first outlet of the turbocharger in a first fluid path, and the second fluid transits from a second inlet of the turbocharger to a second outlet of the turbocharger in a second fluid path separate from the first fluid path.PATENTAttorney Docket No.: SGEO / 0020PC

[0252] Operation 1108 includes flowing the second fluid from the turbocharger to an expander (such as expander 30) coupled to a generator (such as generator 36). Operation 1110 includes operating the expander to reduce the pressure and a temperature of the second fluid. Operation 1112 includes generating electricity using the generator.

[0253] In some embodiments, method 1100 includes producing the first fluid from a subterranean formation into a well (such as first well 44 or well 70), and flowing the first fluid from the well to the turbocharger. In some embodiments, method 1100 includes pumping the first fluid into the well, and injecting the first fluid back into the subterranean formation. In some embodiments, method 1100 includes flowing the first fluid from the turbocharger to a reservoir (such as reservoir 332) prior to pumping the first fluid into the well. In some embodiments, method 1100 includes ceasing production of the first fluid from the well prior to pumping the first fluid into the well.

[0254] In some embodiments, producing the first fluid from the subterranean formation comprises producing the first fluid from the subterranean formation at a first zone of the well, and injecting the first fluid back into the subterranean formation comprises injecting the first fluid into the subterranean formation at a second zone of the well, the second zone different from the first zone.

[0255] In some embodiments, method 1100 includes producing the first fluid from a subterranean formation into a first well (such as first well 44), flowing the first fluid from the first well to the turbocharger, and injecting the first fluid back into the subterranean formation via a second well (such as second well 46).

[0256] In some embodiments, method 1100 may include injecting additional geothermal fluid into the second well, the additional geothermal fluid being sourced from a reservoir (such as reservoir 240). Method 1100 may include injecting the additional geothermal fluid into the second well using a charge pump (such as charge pump 242). Method 1100 may include injecting the additional geothermal fluid into the second well using the charge pump to establish a selected operating pressure at a wellhead of the second well. The operating pressure at the wellhead of the secondPATENTAttorney Docket No.: SGEO / 0020PC well may be selected such that one or more fractures in the subterranean formation coupled to the second well are open.

[0257] It is contemplated that method 1100 may include any one or more of the operations or activities described herein.

[0258] Figure 12 is a flow diagram of a method 1200 of operating a geothermal power system. The geothermal power system may be any of geothermal power system 400 or 500.

[0259] Operation 1202 includes flowing a first fluid into a first inlet of a turbocharger. In some embodiments, the first fluid is a geothermal fluid, such as geothermal fluid 102. In some embodiments, the first fluid is produced from a subterranean formation, such as subterranean formation 42. In some embodiments, the turbocharger is turbocharger 410.

[0260] Operation 1204 includes reducing a pressure of the first fluid in the turbocharger as the first fluid transits from the first inlet of the turbocharger to a first outlet of the turbocharger.

[0261] Operation 1206 includes increasing a pressure of a second fluid in the turbocharger as the second fluid transits from a second inlet of the turbocharger to a second outlet of the turbocharger, the second fluid having a first temperature at the second outlet. In some embodiments, the second fluid is a power fluid, such as power fluid 442. In some embodiments, the first fluid transits from the first inlet of the turbocharger to the first outlet of the turbocharger in a first fluid path, and the second fluid transits from the second inlet of the turbocharger to the second outlet of the turbocharger in a second fluid path separate from the first fluid path.

[0262] Operation 1208 includes flowing the second fluid through a turbine (such as one of the one or more turbines 444) coupled to a generator. In some embodiments, the second fluid enters the turbine at a second temperature substantially equal to the first temperature. In an example, the second temperature is within 10 degrees C, such as within 7 degrees C, within 5 degrees C, or within 2 degrees C, of the firstPATENTAttorney Docket No.: SGEO / 0020PC temperature. In some embodiments, the second fluid does not flow through a heat exchanger between the second outlet of the turbocharger and the turbine.

[0263] Operation 1210 includes generating electricity using the generator.

[0264] Operation 1212 includes flowing the second fluid from the turbine to the second inlet of the turbocharger. In some embodiments, the second fluid exits the turbine at a third temperature, and enters the second inlet of the turbocharger at a fourth temperature substantially equal to the third temperature. In an example, the second temperature is within 10 degrees C, such as within 7 degrees C, within 5 degrees C, or within 2 degrees C, of the third temperature. In some embodiments, the second fluid does not flow through a heat exchanger between the turbine and the second inlet of the turbocharger.

[0265] In some embodiments, method 1200 includes producing the first fluid from a subterranean formation into a well, and flowing the first fluid from the well to the turbocharger. In some embodiments, method 1200 includes pumping the first fluid into the well, and injecting the first fluid back into the subterranean formation. In some embodiments, method 1200 includes flowing the first fluid from the turbocharger to a reservoir (such as reservoir 430) prior to pumping the first fluid into the well. In some embodiments, method 1200 includes ceasing production of the first fluid from the well prior to pumping the first fluid into the well. In some embodiments, producing the first fluid from the subterranean formation comprises producing the first fluid from the subterranean formation at a first zone of the well, and injecting the first fluid back into the subterranean formation comprises injecting the first fluid into the subterranean formation at a second zone of the well, the second zone different from the first zone.

[0266] In some embodiments, method 1200 includes producing the first fluid from a subterranean formation into a first well (such as first well 44), flowing the first fluid from the first well to the turbocharger, and injecting the first fluid back into the subterranean formation via a second well (such as second well 46). In some embodiments, method 1200 includes injecting additional geothermal fluid into the second well, the additional geothermal fluid being sourced from a reservoir (such as reservoir 240). In some embodiments, method 1200 includes injecting the additionalPATENTAttorney Docket No.: SGEO / 0020PC geothermal fluid into the second well using a charge pump (such as charge pump 242). In some embodiments, method 1200 includes injecting the additional geothermal fluid into the second well using the charge pump to establish a selected operating pressure at a wellhead of the second well. The operating pressure at the wellhead of the second well may be selected such that one or more fractures in the subterranean formation coupled to the second well are open.

[0267] It is contemplated that method 1200 may include any one or more of the operations or activities described herein.

[0268] Figure 13 is a flow diagram of a method 1300 of operating a geothermal power system. The geothermal power system may be any of geothermal power system 100, 200, 300, 500, or 600.

[0269] Operation 1302 includes producing a first fluid from a geothermal reservoir. In some embodiments, the first fluid is a geothermal fluid, such as geothermal fluid 102. In some embodiments, the geothermal reservoir is a subterranean formation, such as subterranean formation 42.

[0270] Operation 1304 includes introducing the first fluid into a first turbocharger. In some embodiments, the first turbocharger is any of turbocharger 110, 210, 310, or 610. Operation 1306 includes reducing a pressure of the first fluid in the first turbocharger. Operation 1308 includes conveying the first fluid from the first turbocharger to a heat exchanger. Operation 1310 includes increasing a temperature of a second fluid at the heat exchanger using the first fluid. In some embodiments, the second fluid is a working fluid, such as working fluid 12.

[0271] In some embodiments, method 1300 includes simultaneously flowing the first fluid and the second fluid through the first turbocharger and then through the heat exchanger. In some embodiments, the first fluid transits from a first inlet of the first turbocharger to a first outlet of the first turbocharger in a first fluid path, and the second fluid transits from a second inlet of the first turbocharger to a second outlet of the first turbocharger in a second fluid path separate from the first fluid path.PATENTAttorney Docket No.: SGEO / 0020PC

[0272] In some embodiments, method 1300 includes flowing the second fluid from the heat exchanger to an expander (such as expander 30) coupled to a generator (such as generator 36). In some embodiments, method 1300 includes operating the expander to reduce the pressure and a temperature of the second fluid. In some embodiments, method 1300 includes generating electricity using the generator.

[0273] In some embodiments, method 1300 includes producing the first fluid from a subterranean formation into a well (such as first well 44 or well 70), and flowing the first fluid from the well to the first turbocharger. In some embodiments, method 1300 includes pumping the first fluid into the well, and injecting the first fluid back into the subterranean formation. In some embodiments, method 1300 includes flowing the first fluid from the first turbocharger to a reservoir (such as reservoir 632) prior to pumping the first fluid into the well. In some embodiments, method 1300 includes ceasing production of the first fluid from the well prior to pumping the first fluid into the well.

[0274] In some embodiments, producing the first fluid from the subterranean formation comprises producing the first fluid from the subterranean formation at a first zone of the well, and injecting the first fluid back into the subterranean formation comprises injecting the first fluid into the subterranean formation at a second zone of the well, the second zone different from the first zone.

[0275] In some embodiments, method 1300 includes producing the first fluid from a subterranean formation into a first well (such as first well 44), flowing the first fluid from the first well to the first turbocharger, and injecting the first fluid back into the subterranean formation via a second well (such as second well 46).

[0276] In some embodiments, method 1300 may include injecting additional geothermal fluid into the second well, the additional geothermal fluid being sourced from a reservoir (such as reservoir 240). Method 1300 may include injecting the additional geothermal fluid into the second well using a charge pump (such as charge pump 242). Method 1300 may include injecting the additional geothermal fluid into the second well using the charge pump to establish a selected operating pressure at a wellhead of the second well. The operating pressure at the wellhead of the secondPATENTAttorney Docket No.: SGEO / 0020PC well may be selected such that one or more fractures in the subterranean formation coupled to the second well are open.

[0277] It is contemplated that method 1300 may include any one or more of the operations or activities described herein.

[0278] Aspects of the present disclosure present systems and methods for generating electricity using a geothermal fluid. In some aspects, pressure energy of the geothermal fluid is converted into electricity. In some aspects, heat energy of the geothermal fluid is converted into electricity. In some aspects, a pressure of the geothermal fluid is reduced in a first flow path through a turbocharger, and then increased in a second flow path in the same turbocharger. Benefits of the systems and methods of the present disclosure include more effective use of geothermal resources compared to conventional geothermal power systems.

[0279] In some aspects, a method of operating a geothermal power system includes flowing a first fluid into a first inlet of a first turbocharger, and flowing the first fluid from a first outlet of the first turbocharger to a heat exchanger. The method further includes flowing the first fluid from the heat exchanger to a second inlet of the first turbocharger, and discharging the first fluid from a second outlet of the first turbocharger.

[0280] In some embodiments, the method further includes increasing a pressure of the first fluid in the first turbocharger as the first fluid transits from the second inlet to the second outlet. In some embodiments, the method further includes reducing a pressure of the first fluid in the first turbocharger as the first fluid transits from the first inlet to the first outlet. In some embodiments, the method further includes using heat of the first fluid to increase a temperature of a second fluid at the heat exchanger. In some embodiments, the method further includes flowing the second fluid through an expander coupled to a generator. In some embodiments, the method further includes generating electricity using the generator. In some embodiments, the method further includes flowing the first fluid into a first inlet of a second turbocharger. In some embodiments, the method further includes reducing a pressure of the first fluid in the second turbocharger as the first fluid transits from the first inlet of the secondPATENTAttorney Docket No.: SGEO / 0020PC turbocharger to a first outlet of the second turbocharger. In some embodiments, the method further includes increasing a pressure of a second fluid in the second turbocharger as the second fluid transits from a second inlet of the second turbocharger to a second outlet of the second turbocharger. In some embodiments, the method further includes flowing the second fluid from the second outlet of the second turbocharger to a turbine coupled to a generator. In some embodiments, the method further includes flowing the second fluid through the turbine. In some embodiments, the method further includes generating electricity using the generator.

[0281] In some aspects, a method of operating a geothermal power system includes flowing a first fluid into a first inlet of a turbocharger, and reducing a pressure of the first fluid in the turbocharger as the first fluid transits from the first inlet of the turbocharger to a first outlet of the turbocharger. The method further includes increasing a pressure of a second fluid in the turbocharger as the second fluid transits from a second inlet of the turbocharger to a second outlet of the turbocharger. The second fluid has a first temperature at the second outlet. The method further includes flowing the second fluid through a turbine coupled to a generator. The second fluid enters the turbine at a second temperature substantially equal to the first temperature. The method further includes generating electricity using the generator. The method further includes flowing the second fluid from the turbine to the second inlet of the turbocharger. The second fluid exits the turbine at a third temperature, and enters the second inlet of the turbocharger at a fourth temperature substantially equal to the third temperature.

[0282] In some embodiments, the method further includes producing the first fluid from a subterranean formation into a well, and flowing the first fluid from the well to the turbocharger. In some embodiments, the method further includes pumping the first fluid into the well, and injecting the first fluid back into the subterranean formation. In some embodiments, the method further includes flowing the first fluid from the turbocharger to a reservoir prior to pumping the first fluid into the well. In some embodiments, the method further includes ceasing production of the first fluid from the well prior to pumping the first fluid into the well. In some embodiments, the operation of producing the first fluid from the subterranean formation includes producing the firstPATENTAttorney Docket No.: SGEO / 0020PC fluid from the subterranean formation at a first zone of the well. In some embodiments, the operation of injecting the first fluid back into the subterranean formation includes injecting the first fluid back into the subterranean formation comprises injecting the first fluid into the subterranean formation at the first zone of the well. In some embodiments, the operation of injecting the first fluid back into the subterranean formation includes injecting the first fluid into the subterranean formation at a second zone of the well, the second zone being different from the first zone.

[0283] In some aspects, a geothermal power system includes a heat exchanger fluidically coupled to a first turbocharger. The first turbocharger is configured such that a first fluid enters the first turbocharger at a first inlet, and transits through the first turbocharger in a first fluid path from the first inlet to a first outlet. The heat exchanger receives the first fluid from the first outlet of the first turbocharger, and the first turbocharger receives the first fluid from the heat exchanger at a second inlet of the turbocharger. The first turbocharger is further configured such that the first fluid transits through the first turbocharger in a second fluid path from the second inlet to a second outlet. The second fluid path is separate from the first fluid path.

[0284] In some embodiments, the geothermal power system further includes a binary cycle power plant configured to operate with a second fluid. In some embodiments, the binary cycle power plant includes the heat exchanger, an expander fluidically coupled to the heat exchanger, and a generator coupled to the expander. In some embodiments, the geothermal power system further includes a second turbocharger, wherein a first inlet of the second turbocharger is fluidically coupled to the second outlet of the first turbocharger. In some embodiments, the first fluid transits through the second turbocharger in a third fluid path from the first inlet of the second turbocharger to a first outlet of the second turbocharger. In some embodiments, the geothermal power system further includes a fluid circuit. In some embodiments, the fluid circuit includes the second turbocharger, a turbine fluidically coupled to the second turbocharger, and a generator coupled to the turbine. In some embodiments, the turbine is fluidically coupled to the second turbocharger at a second inlet of the second turbocharger and at a second outlet of the second turbocharger. In some embodiments, a third fluid transits through the second turbocharger in a fourth fluidPATENTAttorney Docket No.: SGEO / 0020PC path from the second inlet of the second turbocharger to the second outlet of the second turbocharger, the fourth fluid path separate from the third fluid path.

[0285] In some aspects, a method of operating a geothermal power system includes flowing a first fluid into a first inlet of a turbocharger, and flowing the first fluid from a first outlet of the turbocharger to a heat exchanger. The method further includes flowing the first fluid from the heat exchanger to a second inlet of the turbocharger, flowing the first fluid from a second outlet of the turbocharger to a turbine coupled to a generator, and generating electricity using the generator.

[0286] In some embodiments, the method further includes increasing a pressure of the first fluid in the first turbocharger as the first fluid transits from the second inlet to the second outlet. In some embodiments, the method further includes reducing a pressure of the first fluid in the first turbocharger as the first fluid transits from the first inlet to the first outlet. In some embodiments, the method further includes increasing a temperature of a second fluid at the heat exchanger using heat of the first fluid. In some embodiments, the method further includes flowing the second fluid through an expander coupled to a generator. In some embodiments, the method further includes generating electricity using the generator. In some embodiments, the method further includes producing the first fluid from a subterranean formation into a well. In some embodiments, the method further includes flowing the first fluid from the well to the turbocharger. In some embodiments, the method further includes flowing the first fluid from the turbine to a reservoir. In some embodiments, the method further includes pumping the first fluid from the reservoir back into the subterranean formation at the well. In some embodiments, the method further includes producing the first fluid from a subterranean formation into a first well. In some embodiments, the method further includes flowing the first fluid from the first well to the turbocharger. In some embodiments, the method further includes flowing the first fluid from the turbine to a second well. In some embodiments, the method further includes injecting the first fluid into the subterranean formation at the second well.

[0287] In some aspects, a method of operating a geothermal power system includes simultaneously flowing a first fluid and a second fluid such that the first fluid passes through a turbocharger and then through a heat exchanger, and the secondPATENTAttorney Docket No.: SGEO / 0020PC fluid passes through the heat exchanger and then through the turbocharger. The method further includes transferring heat from the first fluid to the second fluid at the heat exchanger, and reducing a pressure of the first fluid at the turbocharger by increasing a pressure of the second fluid at the turbocharger. The method further includes flowing the second fluid from the turbocharger to an expander coupled to a generator, operating the expander to reduce the pressure and a temperature of the second fluid, and generating electricity using the generator.

[0288] In some embodiments, the method further includes producing the first fluid from a subterranean formation into a first well, and flowing the first fluid from the first well to the turbocharger. In some embodiments, the method further includes flowing the first fluid from the heat exchanger into a second well, and injecting the first fluid back into the subterranean formation. In some embodiments, the method further includes pumping the first fluid into the first well, and injecting the first fluid back into the subterranean formation. In some embodiments, the method further includes flowing the first fluid from the heat exchanger to a reservoir prior to pumping the first fluid into the first well. In some embodiments, the method further includes ceasing production of the first fluid from the first well prior to pumping the first fluid into the first well.

[0289] In some aspects, a geothermal power system includes a heat exchanger fluidically coupled to a turbocharger. The turbocharger is configured such that a first fluid enters the turbocharger at a first inlet, and transits through the turbocharger in a first fluid path from the first inlet to a first outlet. The heat exchanger receives the first fluid from the first outlet of the turbocharger, and the turbocharger receives the first fluid from the heat exchanger at a second inlet of the turbocharger. The turbocharger is further configured such that the first fluid transits through the turbocharger in a second fluid path from the second inlet to a second outlet. The second fluid path is separate from the first fluid path. The geothermal power system further includes a turbine fluidically coupled to the second outlet of the turbocharger, and a first generator coupled to the turbine.

[0290] In some embodiments, the geothermal power system further includes a binary cycle power plant configured to operate with a second fluid. In somePATENTAttorney Docket No.: SGEO / 0020PC embodiments, the binary cycle power plant further includes the heat exchanger, an expander fluidically coupled to the heat exchanger, and a second generator coupled to the expander. In some embodiments, the turbine receives the first fluid from the second outlet of the turbocharger. In some embodiments, the geothermal power system further includes a reservoir fluidically coupled to an outlet of the turbine. In some embodiments, the reservoir includes one of a pond, a tank, or a subterranean formation. In some embodiments, the geothermal power system further includes a pump configured to inject the first fluid into a well. In some embodiments, the pump is downstream of the turbine. In some embodiments, the well provides the first fluid to the turbocharger.

[0291] In some aspects, a method of operating a geothermal power system includes producing a first fluid from a geothermal reservoir, and introducing the first fluid into a first turbocharger. The method includes reducing a pressure of the first fluid in the first turbocharger. The method includes conveying the first fluid from the first turbocharger to a heat exchanger, and increasing a temperature of a second fluid at the heat exchanger using the first fluid.

[0292] In some embodiments, the method further includes conveying the first fluid from the heat exchanger to a pump, and injecting the first fluid into the introducing the second fluid into the first turbocharger, and increasing a pressure of the second fluid in the first turbocharger. In some embodiments, the second fluid is conveyed from an outlet of the first turbocharger to an inlet of the heat exchanger. In some embodiments, the method further includes conveying the second fluid to a power generation unit. In some embodiments, the power generation unit comprises an expander coupled to a generator. In some embodiments, the second fluid is conveyed from the turbocharger to the heat exchanger and then to the power generation unit. In some embodiments, the method further includes conveying at least a portion of the second fluid from the expander to a second turbocharger. In some embodiments, the method further includes increasing a pressure of the portion of the second fluid in the second turbocharger. In some embodiments, the method further includes conveying the portion of the second fluid from the second turbocharger to the first turbocharger.PATENTAttorney Docket No.: SGEO / 0020PC

[0293] In some aspects, a geothermal power system includes a first turbocharger configured to receive a first fluid produced from a geothermal reservoir. The geothermal power system further includes a heat exchanger flu idical ly coupled to the first turbocharger, and configured to receive the first fluid from the first turbocharger. The geothermal power system further includes a pump fluidically coupled to the heat exchanger, and configured to receive the first fluid from the heat exchanger.

[0294] In some embodiments, the pump is configured to inject the first fluid into a geothermal reservoir. In some embodiments, the heat exchanger is configured to receive a second fluid. In some embodiments, the heat exchanger is configured to transfer heat from the first fluid to the second fluid. In some embodiments, the heat exchanger is configured to receive the second fluid from the first turbocharger. In some embodiments, the geothermal power system further includes a power generation unit fluidically coupled to the heat exchanger. In some embodiments, the power generation unit comprises an expander coupled to a generator. In some embodiments, the expander is configured to receive the second fluid from the heat exchanger. In some embodiments, the geothermal power system further includes a second turbocharger configured to receive at least a portion of the second fluid from the expander. In some embodiments, the second turbocharger is configured to convey the portion of the second fluid to the first turbocharger.

[0295] In some aspects, a geothermal power system includes a heat exchanger configured to receive a first fluid produced from a geothermal reservoir. The geothermal power system further includes a first turbocharger fluidically coupled to the heat exchanger, and configured to receive the first fluid from the heat exchanger. The geothermal power system further includes a pump fluidically coupled to the first turbocharger, and configured to receive the first fluid from the first turbocharger.

[0296] In some embodiments, the pump is configured to inject the first fluid into a geothermal reservoir. In some embodiments, the heat exchanger is configured to receive a second fluid. In some embodiments, the heat exchanger is configured to transfer heat from the first fluid to the second fluid. In some embodiments, the first turbocharger is configured to receive the second fluid from the heat exchanger. In some embodiments, the geothermal power system further includes a powerPATENTAttorney Docket No.: SGEO / 0020PC generation unit fluidically coupled to the first turbocharger. In some embodiments, the power generation unit comprises an expander coupled to a generator. In some embodiments, the expander is configured to receive the second fluid from the first turbocharger. In some embodiments, the geothermal power system further includes a second turbocharger configured to receive at least a portion of the second fluid from the expander. In some embodiments, the second turbocharger is configured to convey the portion of the second fluid to the first turbocharger.

[0297] It is contemplated that any one or more elements or features of any one disclosed embodiment may be beneficially incorporated in any one or more other non- mutually exclusive embodiments. While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

PATENTAttorney Docket No.: SGEO / 0020PCWhat is claimed is:1 . A method of operating a geothermal power system, comprising: flowing a first fluid into a first inlet of a first turbocharger; flowing the first fluid from a first outlet of the first turbocharger to a heat exchanger; flowing the first fluid from the heat exchanger to a second inlet of the first turbocharger; and discharging the first fluid from a second outlet of the first turbocharger.

2. The method of claim 1 , further comprising increasing a pressure of the first fluid in the first turbocharger as the first fluid transits from the second inlet to the second outlet.

3. The method of claim 1 , further comprising reducing a pressure of the first fluid in the first turbocharger as the first fluid transits from the first inlet to the first outlet.

4. The method of claim 1 , further comprising using heat of the first fluid to increase a temperature of a second fluid at the heat exchanger.

5. The method of claim 4, further comprising: flowing the second fluid through an expander coupled to a generator; and generating electricity using the generator.

6. The method of claim 1 , further comprising: flowing the first fluid into a first inlet of a second turbocharger; reducing a pressure of the first fluid in the second turbocharger as the first fluid transits from the first inlet of the second turbocharger to a first outlet of the second turbocharger; and increasing a pressure of a second fluid in the second turbocharger as the second fluid transits from a second inlet of the second turbocharger to a second outlet of the second turbocharger.PATENTAttorney Docket No.: SGEO / 0020PC7. The method of claim 6, further comprising flowing the second fluid from the second outlet of the second turbocharger to a turbine coupled to a generator.

8. The method of claim 7, further comprising: flowing the second fluid through the turbine; and generating electricity using the generator.

9. A method of operating a geothermal power system, comprising: simultaneously flowing a first fluid and a second fluid, wherein: the first fluid passes through a turbocharger and then through a heat exchanger; and the second fluid passes through the heat exchanger and then through the turbocharger; transferring heat from the first fluid to the second fluid at the heat exchanger; reducing a pressure of the first fluid at the turbocharger by increasing a pressure of the second fluid at the turbocharger; flowing the second fluid from the turbocharger to an expander coupled to a generator; operating the expander to reduce the pressure and a temperature of the second fluid; and generating electricity using the generator.

10. The method of claim 9, further comprising producing the first fluid from a subterranean formation into a first well, and flowing the first fluid from the first well to the turbocharger.11 . The method of claim 10, further comprising flowing the first fluid from the heat exchanger into a second well, and injecting the first fluid back into the subterranean formation.PATENTAttorney Docket No.: SGEO / 0020PC12. The method of claim 10, further comprising pumping the first fluid into the first well, and injecting the first fluid back into the subterranean formation.

13. The method of claim 12, further comprising flowing the first fluid from the heat exchanger to a reservoir prior to pumping the first fluid into the first well.

14. The method of claim 12, further comprising ceasing production of the first fluid from the first well prior to pumping the first fluid into the first well.

15. A method of operating a geothermal power system, comprising: flowing a first fluid into a first inlet of a turbocharger; reducing a pressure of the first fluid in the turbocharger as the first fluid transits from the first inlet of the turbocharger to a first outlet of the turbocharger; increasing a pressure of a second fluid in the turbocharger as the second fluid transits from a second inlet of the turbocharger to a second outlet of the turbocharger, the second fluid having a first temperature at the second outlet; flowing the second fluid through a turbine coupled to a generator, wherein the second fluid enters the turbine at a second temperature substantially equal to the first temperature; generating electricity using the generator; and flowing the second fluid from the turbine to the second inlet of the turbocharger, wherein the second fluid exits the turbine at a third temperature, and enters the second inlet of the turbocharger at a fourth temperature substantially equal to the third temperature.

16. The method of claim 15, further comprising producing the first fluid from a subterranean formation into a well, and flowing the first fluid from the well to the turbocharger.

17. The method of claim 16, further comprising pumping the first fluid into the well, and injecting the first fluid back into the subterranean formation.PATENTAttorney Docket No.: SGEO / 0020PC18. The method of claim 17, further comprising flowing the first fluid from the turbocharger to a reservoir prior to pumping the first fluid into the well.

19. The method of claim 17, further comprising ceasing production of the first fluid from the well prior to pumping the first fluid into the well.

20. The method of claim 17, wherein: producing the first fluid from the subterranean formation comprises producing the first fluid from the subterranean formation at a first zone of the well; and injecting the first fluid back into the subterranean formation comprises injecting the first fluid into the subterranean formation at a second zone of the well, the second zone different from the first zone.

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