Control device, geothermal utilization system, control method, and program

Abstract

The control device is provided with: a return water temperature acquisition unit for acquiring the temperature of return water to a return water well of a geothermal energy utilization system provided with heat source well equipment, a geothermal energy utilization circuit, and auxiliary heat supply equipment; the heat source well equipment is provided with a pumping well, a return well, well-side piping extending from the pumping well to the return well, and a heat exchanger provided midway in the well-side piping, the geothermal utilization circuit is provided between the heat exchanger and the machine, and the auxiliary heat supply equipment is provided in the machine in parallel with the geothermal utilization circuit and is provided with a heat source machine; a flow rate control unit that controls the flow rate of the refrigerant flowing from the terrestrial heat utilization circuit to the machine on the basis of the return water temperature; and a heat source machine control unit that controls the start and stop of the heat source machine on the basis of the return water temperature.

Description

Technical Field

[0001] This disclosure relates to control devices, geothermal utilization systems, control methods, and procedures.

[0002] This application is based on priority of Japanese Patent Application No. 2023-162956, filed in Japan on September 26, 2023, the contents of which are incorporated herein by reference. Background Technology

[0003] In recent years, geothermal utilization systems that utilize the heat stored underground have been proposed.

[0004] As a related technology, for example, Patent Document 1 discloses a geothermal utilization system that stores the cold, hot or warm heat discharged from an air conditioning system underground.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent No. 7179905 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] The geothermal utilization system disclosed in Patent Document 1 adjusts the water injection flow rate from the pumping well to the return well based on the set temperature of the groundwater returning to the return well.

[0010] However, for example, in cases where machines such as air conditioning systems require a large heat load, the return water temperature cannot always be adjusted in the geothermal utilization system disclosed in Patent Document 1.

[0011] Therefore, the temperature of the return water can sometimes affect the underground environment.

[0012] This disclosure provides control devices, geothermal utilization systems, control methods, and procedures that are unlikely to have an impact on the underground environment.

[0013] Methods for solving problems

[0014] The control device disclosed herein comprises: a return water temperature acquisition unit for acquiring the return water temperature of a geothermal utilization system to a return water well, the geothermal utilization system comprising a heat source well device, a geothermal utilization circuit, and an auxiliary heat supply device, the heat source well device comprising a pumping well, the return water well, a well-side piping extending from the pumping well to the return water well, and a heat exchanger disposed in the middle of the well-side piping, the geothermal utilization circuit being disposed between the heat exchanger and a machine, the auxiliary heat supply device being disposed in parallel with the geothermal utilization circuit in the machine and comprising a heat source machine; a flow control unit for controlling the flow rate of refrigerant flowing from the geothermal utilization circuit to the machine based on the return water temperature; and a heat source machine control unit for controlling the start and stop of the heat source machine based on the return water temperature.

[0015] The control device disclosed herein includes: a return water temperature acquisition unit for acquiring the return water temperature of a geothermal utilization system to a return water well, the geothermal utilization system including a heat source well device and a geothermal utilization circuit, the heat source well device including a pumping well, the return water well, a well-side piping extending from the pumping well to the return water well, and a heat exchanger disposed in the middle of the well-side piping, the geothermal utilization circuit being disposed between the heat exchanger and a machine; and a flow control unit for controlling the flow rate of refrigerant flowing from the geothermal utilization circuit to the machine based on the return water temperature, the control device further including: a pumping side water level acquisition unit for acquiring a pumping side water level, which is the water level of the pumping well; and a pumping flow rate control unit for controlling the pumping flow rate from the pumping well based on the pumping side water level.

[0016] The control device disclosed herein includes: a return water temperature acquisition unit for acquiring the return water temperature of a geothermal utilization system to a return water well, the geothermal utilization system including a heat source well device and a geothermal utilization circuit, the heat source well device including a pumping well, the return water well, a well-side piping extending from the pumping well to the return water well, and a heat exchanger disposed in the middle of the well-side piping, the geothermal utilization circuit being disposed between the heat exchanger and a machine; and a flow control unit for controlling the flow rate of refrigerant flowing from the geothermal utilization circuit to the machine based on the return water temperature, the control device further including: a return water side water level acquisition unit for acquiring the return water side water level as the water level of the return water well; and a return water flow control unit for controlling the return water flow rate to the return water well based on the return water side water level.

[0017] The geothermal utilization system disclosed herein includes the control device, the heat source well equipment, and the geothermal utilization circuit.

[0018] The control method disclosed herein performs the following processing: obtaining the return water temperature of a geothermal utilization system to a return water well, the geothermal utilization system comprising a heat source well device, a geothermal utilization loop, and an auxiliary heat supply device, the heat source well device comprising a pumping well, the return water well, a well-side piping extending from the pumping well to the return water well, and a heat exchanger disposed in the middle of the well-side piping, the geothermal utilization loop being disposed between the heat exchanger and a machine, the auxiliary heat supply device being disposed in parallel with the geothermal utilization loop at the machine and comprising a heat source unit; controlling the flow rate of refrigerant flowing from the geothermal utilization loop to the machine based on the return water temperature; and controlling the start and stop of the heat source unit based on the return water temperature.

[0019] The control method disclosed herein performs the following processing: obtaining the return water temperature of a geothermal utilization system to a return water well, the geothermal utilization system comprising a heat source well device and a geothermal utilization circuit, the heat source well device comprising a pumping well, the return water well, a well-side piping extending from the pumping well to the return water well, and a heat exchanger disposed in the middle of the well-side piping, the geothermal utilization circuit being disposed between the heat exchanger and a machine; controlling the flow rate of refrigerant flowing from the geothermal utilization circuit to the machine based on the return water temperature; obtaining the pumping-side water level, which is the water level of the pumping well; and controlling the pumping flow rate from the pumping well based on the pumping-side water level.

[0020] The control method disclosed herein performs the following processing: obtaining the return water temperature of a geothermal utilization system to a return water well, the geothermal utilization system comprising a heat source well device and a geothermal utilization circuit, the heat source well device comprising a pumping well, the return water well, a well-side piping extending from the pumping well to the return water well, and a heat exchanger disposed in the middle of the well-side piping, the geothermal utilization circuit being disposed between the heat exchanger and the machine; controlling the flow rate of refrigerant flowing from the geothermal utilization circuit to the machine based on the return water temperature; obtaining the return water side water level as the water level of the return water well; and controlling the return water flow rate to the return water well based on the return water side water level.

[0021] The program disclosed herein enables a computer to perform the following processes: acquiring the return water temperature of a geothermal utilization system to a return water well, the geothermal utilization system comprising a heat source well device, a geothermal utilization loop, and an auxiliary heat supply device, the heat source well device comprising a pumping well, the return water well, wellside piping extending from the pumping well to the return water well, and a heat exchanger disposed in the middle of the wellside piping, the geothermal utilization loop being disposed between the heat exchanger and a machine, the auxiliary heat supply device being disposed in parallel with the geothermal utilization loop at the machine and comprising a heat source unit; controlling the flow rate of refrigerant flowing from the geothermal utilization loop to the machine based on the return water temperature; and controlling the start and stop of the heat source unit based on the return water temperature.

[0022] The program disclosed herein enables a computer to perform the following processes: acquiring the return water temperature of a geothermal utilization system to a return water well, the geothermal utilization system comprising a heat source well device and a geothermal utilization loop, the heat source well device comprising a pumping well, the return water well, wellside piping extending from the pumping well to the return water well, and a heat exchanger disposed midway along the wellside piping, the geothermal utilization loop being disposed between the heat exchanger and a machine; controlling the flow rate of refrigerant flowing from the geothermal utilization loop to the machine based on the return water temperature; acquiring the pumping side water level, which is the water level of the pumping well; and controlling the pumping flow rate from the pumping well based on the pumping side water level.

[0023] The program disclosed herein enables a computer to perform the following processes: acquiring the return water temperature of a geothermal utilization system to a return water well, the geothermal utilization system comprising a heat source well device and a geothermal utilization circuit, the heat source well device comprising a pumping well, the return water well, wellside piping extending from the pumping well to the return water well, and a heat exchanger disposed midway along the wellside piping, the geothermal utilization circuit being disposed between the heat exchanger and a machine; controlling the flow rate of refrigerant flowing from the geothermal utilization circuit to the machine based on the return water temperature; acquiring the return water side level as the water level of the return water well; and controlling the return water flow rate to the return water well based on the return water side level.

[0024] Invention Effects

[0025] The control device, geothermal utilization system, control method, and procedure disclosed herein are unlikely to have an impact on the underground environment. Attached Figure Description

[0026] Figure 1 This is a system diagram of a geothermal utilization system according to an embodiment of this disclosure.

[0027] Figure 2 This is a configuration diagram illustrating an example of the installation state of a water level gauge under the natural water level of a geothermal utilization system according to an embodiment of the present disclosure.

[0028] Figure 3 This is a configuration diagram illustrating an example of the installation state of the water level gauge during pumping and return water in a geothermal utilization system according to an embodiment of the present disclosure.

[0029] Figure 4 This is a detailed system diagram of the flow path adjustment device according to an embodiment of the present disclosure.

[0030] Figure 5 This is a block diagram of a control device according to an embodiment of the present disclosure.

[0031] Figure 6 This is a flowchart of a method for controlling the return water temperature according to an embodiment of the present disclosure.

[0032] Figure 7 This is a flowchart of a method for controlling the return water temperature according to an embodiment of the present disclosure.

[0033] Figure 8 This is a flowchart of a method for controlling the water level on the pumping side according to an embodiment of this disclosure.

[0034] Figure 9 This is a flowchart of a method for controlling the water level on the return water side according to an embodiment of this disclosure.

[0035] Figure 10 This is a diagram illustrating an example of the concept of load heat sharing in the heat source well equipment and auxiliary heat supply equipment according to embodiments of the present disclosure.

[0036] Figure 11 This is an explanatory diagram illustrating the function of an example of the hysteresis set in the start-up and stop temperatures of the heat source machine according to an embodiment of this disclosure.

[0037] Figure 12 This is an explanatory diagram illustrating the function of an example of the hysteresis setting in the start-up and stop-down water levels of the heat source machine according to an embodiment of this disclosure. Detailed Implementation

[0038] Hereinafter, embodiments of the present disclosure will be described using the accompanying drawings. In all the drawings, the same or equivalent components are labeled with the same reference numerals and common descriptions are omitted.

[0039] <Implementation Method>

[0040] Reference Figures 1 to 12 The implementation methods of the geothermal utilization system disclosed herein will be described.

[0041] (Composition of a geothermal utilization system)

[0042] like Figure 1 As shown, the geothermal utilization system 1 includes a heat source well device 10, a geothermal utilization circuit 20, an auxiliary heat supply device 30, and a control device 50.

[0043] The heat source well equipment 10, the geothermal utilization circuit 20, and the machine AA are connected in series in a manner that enables them to receive heat.

[0044] The auxiliary heat supply equipment 30 and the machine AA are connected in parallel with the heat source well equipment 10 and the geothermal utilization circuit 20 in a manner that can receive heat.

[0045] When cooling is used in machine AA (e.g., air conditioning load) (hereinafter referred to as "cooling operation"), the geothermal utilization system 1 uses the cold and heat stored in the heat source well equipment 10 as cold water for cooling, and at the same time stores the warm waste heat from machine AA as warm water in the heat source well equipment 10.

[0046] When the machine AA is used for heating (hereinafter referred to as "heating operation"), the geothermal utilization system 1 uses the heat stored in the heat source well equipment 10 as warm water for heating, and at the same time stores the cold and hot waste heat from the machine AA as cold water in the heat source well equipment 10.

[0047] For example, the geothermal utilization system 1 can also be a system that uses the waste heat (warm water) from summer cooling to winter heating by switching the pumping well and return well according to each season, and uses the waste heat (cold water) from winter heating to summer cooling.

[0048] (Composition of heat source well equipment)

[0049] The heat source well equipment 10 includes a warm water well 11, a cold water well 12, well-side piping 13, and a heat exchanger 14.

[0050] The heat source well equipment 10 is also equipped with a water thermometer 15 and a water level gauge 16 on the side of each of the warm water well 11 and the cold water well 12.

[0051] In order for the heat storage to be utilized by the machine AA, the heat source well equipment 10 draws groundwater from one of the warm water well 11 and the cold water well 12 to the surface, performs heat exchange on the surface for heat utilization, and injects it into the other of the warm water well 11 and the cold water well 12.

[0052] That is to say, the heat storage utilization mode of the heat source well equipment 10 has a cold and hot utilization mode and a warm and hot utilization mode. The cold and hot utilization mode is the mode of drawing groundwater from the cold water well 12 and injecting it into the warm water well 11 during the cooling operation. The warm and hot utilization mode is the mode of drawing groundwater from the warm water well 11 and injecting it into the cold water well 12 during the heating operation.

[0053] In the case of cold and hot utilization mode, groundwater is drawn from the aquifer LY via cold water well 12, so cold water well 12 functions as a pumping well.

[0054] On the other hand, in the case of hot and cold utilization mode, the extracted groundwater is returned to the aquifer LY via the warm water well 11, so the warm water well 11 functions as a return water well.

[0055] In the case of the heat utilization mode, groundwater is drawn from the aquifer LY via the warm water well 11, so the warm water well 11 functions as a pumping well.

[0056] On the other hand, in the case of warm and hot utilization mode, the extracted groundwater is returned to the aquifer LY via cold water well 12, so cold water well 12 functions as a return water well.

[0057] (The composition of warm water wells and cold water wells)

[0058] Warm water well 11 and cold water well 12 extend from the ground into the aquifer LY.

[0059] The warm water well 11 and the cold water well 12 are configured to each have a shell with a screen, etc., and to draw groundwater from the aquifer LY into the interior of the warm water well 11 and the cold water well 12, or to return groundwater from the interior of the warm water well 11 and the cold water well 12 to the aquifer LY.

[0060] During the steady-state operation of the geothermal utilization system 1, warm water is stored in the aquifer LY surrounding the warm water well 11, and cold water is stored in the aquifer LY surrounding the cold water well 12.

[0061] The warm water well 11 and the cold water well 12 are set at a distance that fully separates them from each other to the extent that the accumulated warm water and cold water do not mix.

[0062] (Composition of wellside piping)

[0063] The wellside piping 13 extends from the warm water well 11 to the cold water well 12.

[0064] The wellside piping 13 connects the warm water well 11 to the cold water well 12.

[0065] like Figure 1 As shown, the first end 131, which is one end of the well-side piping 13, extends into the interior of the warm water well 11 and is immersed in the groundwater inside the warm water well 11.

[0066] The second end 132, which is the other end of the well-side piping 13, extends into the interior of the cold water well 12 and is soaked in groundwater inside the cold water well 12.

[0067] A submersible pump PP, a water injection valve VA, and a check valve VB are respectively provided at the first end 131 and the second end 132, which are configured to pump water from each well into the wellside piping 13, or inject water from the wellside piping 13 into each well.

[0068] The submersible pump PP can change its output through inverter control according to the instructions from the control device 50.

[0069] (Composition of a heat exchanger)

[0070] The heat exchanger 14 is located in the middle of the wellside piping 13.

[0071] The heat exchanger 14 performs heat exchange between the water in the wellside piping 13 and the heat medium on the geothermal utilization circuit 20 side.

[0072] During cooling operation (in the case of cold and heat utilization mode), the heat exchanger 14 exchanges heat between cold water, which is groundwater drawn from the cold water well 12 and flowing in the well-side piping 13, and the heat medium on the geothermal utilization circuit 20 side. The heat or cold obtained by the heat medium on the geothermal utilization circuit 20 side is utilized by the machine AA via the geothermal utilization circuit 20. On the other hand, warm water, which is groundwater that has undergone heat exchange, flows from the heat exchanger 14 into the well-side piping 13 and is injected into the warm water well 11. Through this injection, warm water heat storage is carried out in the warm water well 11.

[0073] During heating operation (in the case of warm water utilization mode), heat exchanger 14 exchanges heat between warm water, which is groundwater drawn from warm water well 11 and flowing in well-side piping 13, and the heat medium on the geothermal utilization circuit 20 side. The heat obtained by the heat medium on the geothermal utilization circuit 20 side is utilized by machine AA via the geothermal utilization circuit 20. On the other hand, cold water, which is groundwater that has undergone heat exchange, flows from heat exchanger 14 into well-side piping 13 and is injected into cold water well 12. Through this injection, cold water heat storage is performed in cold water well 12.

[0074] Here, "cold water" refers to water with a temperature lower than the initial underground temperature of the groundwater in aquifer LY. On the other hand, "warm water" refers to water with a temperature higher than the aforementioned initial underground temperature. For example, the initial underground temperature of the groundwater in aquifer LY is 18°C.

[0075] (Composition of a water thermometer)

[0076] The water thermometer 15 on the side of the cold water well 12 is located midway along the well-side piping 13 from the cold water well 12 toward the heat exchanger 14. For example, the water thermometer 15 on the side of the cold water well 12 can also be located on the ground surface directly above the cold water well 12.

[0077] The water thermometer 15 on the side of the cold water well 12 measures the temperature of the water flowing in the wellside piping 13 on the side of the cold water well 12 and outputs the measurement result to the control device 50.

[0078] The water thermometer 15 on the side of the warm water well 11 is located midway along the well-side piping 13 from the heat exchanger 14 toward the warm water well 11. For example, the water thermometer 15 on the side of the warm water well 11 can also be located on the ground surface directly above the warm water well 11.

[0079] The thermometer 15 on the side of the warm water well 11 measures the temperature of the water flowing in the wellside piping 13 on the side of the warm water well 11 and outputs the measurement result to the control device 50.

[0080] During cooling operation (in the case of cold and heat utilization mode), the water thermometer 15 on the side of the cold water well 12 functions as a water thermometer to measure the pumping temperature from the pumping well.

[0081] At this time, the water thermometer 15 on the side of the cold water well 12 will use the measurement result as the output control device 50 for the pumping temperature.

[0082] On the other hand, during the cooling operation, the water thermometer 15 on the side of the warm water well 11 functions as a water thermometer to measure the temperature of the return water to the return water well.

[0083] At this time, the water thermometer 15 on the side of the warm water well 11 outputs the measurement result as the return water temperature to the control device 50.

[0084] During heating operation (in the case of heat utilization mode), the water thermometer 15 on the side of the warm water well 11 functions as a water thermometer to measure the temperature of the pumped water from the pumping well.

[0085] At this time, the water thermometer 15 on the side of the warm water well 11 outputs the measurement result as the pumping temperature to the control device 50.

[0086] On the other hand, during heating operation, the water thermometer 15 on the cold water well 12 side functions as a water thermometer to measure the temperature of the return water to the return water well.

[0087] At this time, the water thermometer 15 on the side of the cold water well 12 outputs the measurement result as the return water temperature to the control device 50.

[0088] (Composition of a water level gauge)

[0089] The water level gauge 16 on the side of the cold water well 12 is installed inside the cold water well 12.

[0090] The water level gauge 16 on the side of the cold water well 12 measures the water level in the cold water well 12 and outputs the measurement result to the control device 50.

[0091] The water level gauge 16 is installed inside the warm water well 11.

[0092] The water level gauge 16 on the side of the warm water well 11 measures the water level in the warm water well 11 and outputs the measurement result to the control device 50.

[0093] During cooling operation (in the case of cold and heat utilization mode), the water level gauge 16 on the side of the cold water well 12 functions as a water level gauge for measuring the water level of the pumping well, i.e., the water level on the pumping side.

[0094] At this time, the water level gauge 16 on the side of the cold water well 12 outputs the measurement result as the water level on the pumping side to the control device 50.

[0095] On the other hand, during the cooling operation, the water level gauge 16 on the side of the warm water well 11 functions as a water level gauge for measuring the water level of the return water well, i.e., the water level on the return water side.

[0096] At this time, the water level gauge 16 on the side of the warm water well 11 outputs the measurement result as the water level on the return water side to the control device 50.

[0097] During heating operation (in the case of warm water utilization mode), the water level gauge 16 on the side of the warm water well 11 functions as a water level gauge for measuring the water level of the pumping well, i.e., the water level on the pumping side.

[0098] At this time, the water level gauge 16 on the side of the warm water well 11 outputs the measurement result as the water level on the pumping side to the control device 50.

[0099] On the other hand, during heating operation, the water level gauge 16 on the side of the cold water well 12 functions as a water level gauge for measuring the water level of the return water well, i.e., the water level on the return water side.

[0100] At this time, the water level gauge 16 on the side of the cold water well 12 outputs the measurement result as the water level on the return water side to the control device 50.

[0101] For example, each water level gauge 16 measures the distance from the water surface to the position where the water level gauge 16 is set as the water level.

[0102] For example, each water level gauge 16 can also be set to measure at the natural water level. Figure 2 The water level shown.

[0103] For example, each water level gauge 16 can also be set to measure water during pumping and return. Figure 3 The water level shown.

[0104] (The structure of a geothermal utilization loop)

[0105] The geothermal utilization circuit 20 is located between the heat exchanger 14 and the machine AA.

[0106] The geothermal utilization circuit 20, according to the instructions of the control device 50, mediates and controls the heat reception between the heat exchanger 14 and the machine AA.

[0107] For example, the geothermal utilization circuit 20 may also include a heat pump 21, a flow adjustment device 22, and a main piping 23.

[0108] (Components of a heat pump)

[0109] The heat pump 21 is equipped with a condenser, evaporator, compressor, etc.

[0110] For example, heat pump 21 is a turbine heat pump.

[0111] The heat pump 21 is located between the heat exchanger 14 and the flow adjustment device 22.

[0112] The heat pump 21 cools or heats the heat medium after it has exchanged heat with the water in the wellside piping 13 through the heat exchanger 14. Thus, the heat pump 21 supplies the stored cold or hot heat obtained from the water in the wellside piping 13 to the machine AA, and on the other hand, recovers the hot or cold waste heat discharged from the machine AA and stores it in the water in the wellside piping 13 through the heat exchanger 14.

[0113] During cooling operation (in the case of heat and cold utilization mode), the heat pump 21 supplies the stored heat and cold obtained from the wellside piping 13 to the machine AA via the heat exchanger 14 and via the heat medium flowing between the heat exchanger 14 and the machine AA. On the other hand, the heat pump 21 stores the warm waste heat discharged from the machine AA in the water within the wellside piping 13 via the heat medium flowing between the machine AA and the heat exchanger 14.

[0114] During heating operation (in the case of heat utilization mode), the heat pump 21 supplies the stored heat from the wellside piping 13 to the machine AA via the heat exchanger 14 and via the heat medium flowing between the heat exchanger 14 and the machine AA. On the other hand, the heat pump 21 stores the cold and hot waste heat discharged from the machine AA in the water within the wellside piping 13 via the heat medium flowing between the machine AA and the heat exchanger 14.

[0115] (Composition of the flow adjustment device)

[0116] The flow rate adjustment device 22 adjusts the flow rate FL of the heat medium flowing from the geothermal utilization circuit 20 to the machine AA.

[0117] like Figure 4 As shown, for example, the flow rate regulating device 22 may also include a bypass valve 223 for adjusting the flow rate FL via a bypass. Furthermore, the flow rate regulating device 22 may also include a pump 221 and an electric valve 222 midway through the path connecting the heat pump 21 and the main piping 23 for adjusting the flow rate FL.

[0118] (Composition of main piping)

[0119] The main piping 23 extends from the flow adjustment device 22 to the machine AA.

[0120] The main piping 23 connects the flow regulating device 22 and the machine AA in such a way that the heat medium can circulate between the flow regulating device 22 and the machine AA.

[0121] (Composition of auxiliary heat supply equipment)

[0122] Auxiliary heat supply equipment 30 and auxiliary heat source well equipment 10 provide at least one of the warm and cold heat supply to machine AA.

[0123] When refrigeration is used in machine AA, auxiliary heat supply equipment 30 supplies cold and heat to machine AA and recovers warm and hot waste heat from machine AA.

[0124] When heating is used in machine AA, auxiliary heat supply equipment 30 supplies heat to machine AA and recovers cold and hot waste heat from machine AA.

[0125] The auxiliary heat supply equipment 30 has multiple heat source units 31 and auxiliary piping 32.

[0126] Each heat source 31 supplements the machine AA with at least one of the cold or hot and warm heat supplied.

[0127] For example, multiple heat source units 31 include turbine chillers, air-cooled heat pumps, absorption chillers, etc.

[0128] Auxiliary piping 32 extends from multiple heat source units 31 to machine AA.

[0129] The auxiliary piping 32 connects multiple heat source machines 31 and machine AA in a manner in which the heat medium can circulate between multiple heat source machines 31 and machine AA.

[0130] For example, the auxiliary heat supply equipment 30 may also have an auxiliary flow adjustment device 33 in the middle of the auxiliary piping 32. In this case, the auxiliary flow adjustment device 33 has the same bypass valve, pump and electric valve as the flow adjustment device 22, and the auxiliary flow adjustment device 33 adjusts the flow rate of the refrigerant flowing between the auxiliary heat supply equipment 30 and the machine AA according to the instructions of the control device 50.

[0131] (Composition of the control device)

[0132] like Figure 5 As shown, the control device 50 includes a return water temperature acquisition unit 511 and a flow control unit 512.

[0133] For example, the control device 50 may also functionally include a heat source control unit 513, a pumping side water level acquisition unit 514, a pumping flow control unit 515, a return water side water level acquisition unit 516, and a return water flow control unit 517.

[0134] The control device 50 has a CPU (Central Processing Unit) 51, a memory 52, a communication interface 53, and a recording medium 54 as its hardware components.

[0135] The CPU51 is a processor that performs various functions by following pre-prepared programs. The functions of the CPU51 will be described later.

[0136] The memory 52 has the storage area required for the operation of the CPU 51.

[0137] The communication interface 53 is a connection interface for communicatively connecting with other devices via a communication line or the like, and is configured to send instructions or responses to other devices or receive instructions or responses from other devices.

[0138] The recording medium 54 is a local recording medium located inside the housing of the control device 50, and is a high-capacity storage device such as HDD (Hard Disk Drive) or SSD (Solid State Drive).

[0139] Next, the function of the CPU 51 of the control device 50 will be explained.

[0140] CPU 51 performs the functions of return water temperature acquisition unit 511 and flow control unit 512 as described above by operating according to a pre-prepared program.

[0141] Furthermore, the CPU 51 can also perform the functions described above as the heat source control unit 513, the pumping side water level acquisition unit 514, the pumping flow control unit 515, the return water side water level acquisition unit 516, and the return water flow control unit 517 by operating according to a pre-prepared program.

[0142] The return water temperature acquisition unit 511 acquires the measurement results of the water thermometer 15 on the side of the cold water well 12 or the water thermometer 15 on the side of the warm water well 11 as the return water temperature to the return water well.

[0143] The pumping side water level acquisition unit 514 acquires the measurement results of the water level gauge 16 on the side of the warm water well 11 or the water level gauge 16 on the side of the cold water well 12 as the pumping side water level.

[0144] The return water level acquisition unit 516 acquires the measurement results of the water level gauge 16 on the side of the cold water well 12 or the water level gauge 16 on the side of the warm water well 11 as the return water level.

[0145] The flow control unit 512 controls the flow adjustment device 22 based on the obtained return water temperature, thereby controlling the flow rate FL.

[0146] For example, the flow control unit 512 controls the flow adjustment device 22 based on the obtained pumping side water level, thereby controlling the flow rate FL.

[0147] For example, the flow control unit 512 controls the flow adjustment device 22 based on the obtained return water level, thereby controlling the flow rate FL.

[0148] For example, the flow control unit 512 can also control the auxiliary flow adjustment device 33 based on the obtained return water temperature, thereby adjusting the flow rate of the refrigerant flowing between the auxiliary heat supply equipment 30 and the machine AA.

[0149] For example, the flow control unit 512 can also control the auxiliary flow adjustment device 33 based on the obtained pumping side water level, thereby adjusting the flow rate of the refrigerant flowing between the auxiliary heat supply equipment 30 and the machine AA.

[0150] For example, the flow control unit 512 can also control the auxiliary flow adjustment device 33 based on the obtained return water level, thereby adjusting the flow rate of the refrigerant flowing between the auxiliary heat supply equipment 30 and the machine AA.

[0151] The heat source control unit 513 can also control the start and stop of each heat source unit 31 based on the obtained return water temperature.

[0152] For example, the heat source control unit 513 can also control the start and stop of each heat source unit 31 based on the obtained water level on the pumping side.

[0153] For example, the heat source control unit 513 can also control the start and stop of each heat source unit 31 based on the obtained return water level.

[0154] For example, the heat source control unit 513 can also perform increase or decrease segment control of multiple heat sources 31.

[0155] The pumping flow control unit 515 controls the pumping flow rate from the pumping well based on the obtained pumping side water level.

[0156] The return water flow control unit 517 controls the return water flow to the return water well based on the obtained return water level.

[0157] (The operation of the control device)

[0158] An example of the operation of the control device 50 in this embodiment will be described.

[0159] The operation of the control device 50 is equivalent to the implementation of the control method.

[0160] Control device 50 implementation Figures 6 to 9 The steps shown.

[0161] (Action for controlling return water temperature)

[0162] First, the operation of the return water temperature control will be explained.

[0163] When geothermal utilization system 1 is started, such as Figure 6As shown, when the control device 50 determines whether the machine AA is in cooling operation (ST00).

[0164] (Return water temperature control during refrigeration operation)

[0165] In ST00, when it is determined that the system is in cooling operation (ST00: Yes), the return water temperature acquisition unit 511 acquires the measurement result of the water thermometer 15 on the warm water well 11 side as the return water temperature, and determines whether the acquired return water temperature is higher than the first start-up temperature (e.g., 24°C) at which the heat source unit 31 should be started (ST01). For example, the first start-up temperature is a preset value.

[0166] In ST01, if it is determined that the obtained return water temperature is higher than the first start-up temperature (ST01: Yes), the heat source control unit 513 determines whether there is a heat source 31 (other heat source) that can be started among the multiple heat source units 31 (ST02).

[0167] In ST02, if it is determined that there is a startable heat source 31 (ST02: Yes), the heat source control unit 513 starts the startable heat source 31 (ST03), and the control device 50 returns to the execution of ST01.

[0168] For example, in ST03, the heat source control unit 513 first starts one (configurable and changeable) heat source 31 that can be started. If multiple heat source 31s can be started, the heat source control unit 513 can perform increase / decrease segment control by repeatedly performing ST01 to ST03. At this time, the heat source control unit 513 can also observe the heat or flow rate supplied to machine AA and perform increase / decrease segment control accordingly.

[0169] On the other hand, the flow control unit 512 controls the flow rate FL in a manner that makes the return water temperature of the heat source well equipment 10 within a preset allowable value (below the preset upper limit value) to suppress the load on the heat source well equipment 10.

[0170] In ST02, if it is determined that there is no heat source unit 31 that can be started (ST02: No), the control device 50 determines whether the protection of the aquifer LY should take precedence over ensuring the air conditioning capacity of the machine AA (ST04). For example, the control device 50 may also determine whether the protection of the aquifer LY should take precedence over ensuring the air conditioning capacity of the machine AA according to the policy input by the user or others.

[0171] In ST04, if it is determined that the protection of the aquifer LY should be prioritized (ST04: Yes), the flow control unit 512 controls the flow rate FL (ST05), and the control device 50 returns to the implementation of ST01.

[0172] For example, in ST05, the flow control unit 512 can also control the flow rate FL by opening the bypass valve 223. Through this control, the load can be reduced by bypassing, and the return water temperature can be controlled.

[0173] Furthermore, in ST05, the flow control unit 512 can also control the auxiliary flow adjustment device 33 to increase the flow rate of the hot medium (hot or cold medium) flowing between the auxiliary heat supply equipment 30 and the machine AA.

[0174] In ST04, if it is determined that the air conditioning capacity of machine AA should be ensured (ST04: No), control device 50 stops the heat supply from geothermal utilization system 1 to machine AA (ST06). Afterwards, the user and others investigate using other systems that can replace geothermal utilization system 1 and ensure the air conditioning capacity of machine AA.

[0175] In ST01, if it is determined that the obtained return water temperature is not higher than the first start-up temperature (ST01: No), the return water temperature acquisition unit 511 determines whether the obtained return water temperature is lower than the first stop temperature (e.g., 20°C) at which the heat source unit 31 should be stopped (ST07). For example, the first stop temperature is a preset value.

[0176] Here, when the geothermal utilization system 1 is cooling the machine AA, in order to have a lag between the start-up and stop conditions of the heat source machine 31, the first stop temperature is set to be lower than the first start-up temperature.

[0177] In ST07, if it is not determined that the obtained return water temperature is lower than the first stop temperature (ST07: No), the control device 50 returns to the implementation of ST01.

[0178] In ST07, if it is determined that the obtained return water temperature is lower than the first stop temperature (ST07: Yes), the heat source machine control unit 513 determines whether there is a heat source machine 31 that is started (other than the heat source machines included in the heat source well equipment 10) among the multiple heat source machines 31 (ST08).

[0179] In ST08, if it is determined that a heat source 31 is in operation (ST08: Yes), the heat source control unit 513 stops the heat source 31 in operation (ST09), and the control device 50 returns to the execution of ST01.

[0180] In ST08, if it is determined that there is no heat source machine 31 in operation (ST08: No), the control device 50 returns to the implementation of ST01.

[0181] In ST00, if it is not determined that the machine is in cooling operation (ST00: No), the control device 50 determines whether the machine AA is in heating operation (ST10).

[0182] In ST10, if it is not determined that the device is in heating operation (ST10: No), the control device 50 causes the heat source well equipment 10 to perform cold and heat storage operation or heat storage operation as other control (ST11).

[0183] (Return water temperature control during heating operation)

[0184] In ST10, if the system is determined to be in heating operation (ST10: Yes), as follows: Figure 7 As shown, the return water temperature acquisition unit 511 acquires the measurement result of the water thermometer 15 on the cold water well 12 side as the return water temperature, and determines whether the acquired return water temperature is lower than the second start-up temperature (e.g., 8°C) at which the heat source machine 31 should be started (ST21). For example, the second start-up temperature is a preset value.

[0185] In ST21, if it is determined that the obtained return water temperature is lower than the second start-up temperature (ST21: Yes), the heat source control unit 513 determines whether there is a heat source 31 that can be started (other heat source) among the multiple heat source units 31 (ST22).

[0186] In ST22, if it is determined that there is a startable heat source 31 (ST22: Yes), the heat source control unit 513 starts the startable heat source 31 (ST23), and the control device 50 returns to the execution of ST21.

[0187] For example, in ST23, the heat source control unit 513 first starts one (configurable and changeable) heat source 31 that can be started. If multiple heat source 31s can be started, the heat source control unit 513 can perform increase / decrease segment control by repeatedly performing ST21 to ST23. At this time, the heat source control unit 513 can also observe the heat or flow rate supplied to machine AA and perform increase / decrease segment control accordingly.

[0188] On the other hand, the flow control unit 512 controls the flow rate FL in a manner that makes the return water temperature of the heat source well equipment 10 within a preset allowable value (above the preset lower limit value) to suppress the load on the heat source well equipment 10.

[0189] In ST22, if it is determined that there is no heat source unit 31 that can be started (ST22: No), the control device 50 determines whether the protection of the aquifer LY should take precedence over ensuring the air conditioning capacity of the machine AA (ST24). For example, the control device 50 may also determine whether the protection of the aquifer LY should take precedence over ensuring the air conditioning capacity of the machine AA according to the policy input by the user or others.

[0190] In ST24, if it is determined that the protection of the aquifer LY should be prioritized (ST24: Yes), the flow control unit 512 controls the flow rate FL (ST25), and the control device 50 returns to the implementation of ST21.

[0191] For example, in ST25, the flow control unit 512 can also control the flow rate FL by opening the bypass valve 223. Through this control, the load can be reduced by bypassing, and the return water temperature can be controlled.

[0192] Furthermore, in ST25, the flow control unit 512 can also control the auxiliary flow adjustment device 33 to increase the flow rate of the heat medium (warm medium) flowing between the auxiliary heat supply equipment 30 and the machine AA.

[0193] In ST24, if it is determined that the air conditioning capacity of machine AA should be ensured (ST24: No), control device 50 stops the heat supply from geothermal utilization system 1 to machine AA (ST26). Afterwards, the user and others investigate using other systems that can replace geothermal utilization system 1 and ensure the air conditioning capacity of machine AA.

[0194] In ST21, if it is determined that the obtained return water temperature is not lower than the second start-up temperature (ST21: No), the return water temperature acquisition unit 511 determines whether the obtained return water temperature is higher than the second stop temperature (e.g., 12°C) at which the heat source unit 31 should be stopped (ST27). For example, the second stop temperature is a preset value.

[0195] Here, when the geothermal utilization system 1 is heating the machine AA, in order to have a lag between the start-up and stop conditions of the heat source machine 31, the second stop temperature is set to be higher than the second start-up temperature.

[0196] In ST27, if it is not determined that the obtained return water temperature is higher than the second stop temperature (ST27: No), the control device 50 returns to the implementation of ST21.

[0197] In ST27, if it is determined that the obtained return water temperature is higher than the second stop temperature (ST27: Yes), the heat source machine control unit 513 determines whether there is a heat source machine 31 that is started (other than the heat source machines included in the heat source well equipment 10) among the multiple heat source machines 31 (ST28).

[0198] In ST28, if it is determined that a heat source 31 is in operation (ST28: Yes), the heat source control unit 513 stops the heat source 31 in operation (ST29), and the control device 50 returns to the execution of ST21.

[0199] In ST28, if it is determined that there is no heat source machine 31 in operation (ST28: No), the control device 50 returns to the implementation of ST21.

[0200] (The action of controlling the water level in the pumping well)

[0201] The actions for controlling the water level in the pumping well are explained.

[0202] When geothermal utilization system 1 is started, such as Figure 8 As shown, the pumping side water level acquisition unit 514 acquires the measurement result of the water level gauge 16 on the pumping well side as the pumping side water level, and determines whether the acquired pumping side water level is higher than the first limit water level (e.g., 3m) (ST41). For example, the first limit water level is a preset value.

[0203] Here, the first limiting water level is the water level at which the pumping flow should be limited and the heat source machine 31 should be started if the water level is below this level.

[0204] It should be noted that in this water level control during refrigeration operation, the pumping well is the cold water well 12, and the return water well is the warm water well 11.

[0205] On the other hand, in the water level control during heating operation, the pumping well is a warm water well 11, and the return water well is a cold water well 12.

[0206] In ST41, if it is determined that the obtained pumping side water level is not higher than the first limit water level (determined to be below the first limit water level) (ST41: No), the heat source machine control unit 513 determines whether there is a heat source machine 31 that can be started (other heat source machines) among the multiple heat source machines 31 (ST42).

[0207] In ST42, if it is determined that there is a startable heat source 31 (ST42: Yes), the heat source control unit 513 starts the startable heat source 31 (ST43), and the control device 50 returns to the execution of ST41.

[0208] For example, in ST43, the heat source control unit 513 first starts one (configurable and changeable) heat source unit 31 that can be started. If multiple heat source units 31 can be started, the heat source control unit 513 can perform increase / decrease segment control by repeatedly performing ST41 to ST43. At this time, the heat source control unit 513 can also observe the heat or flow rate supplied to machine AA and perform increase / decrease segment control accordingly.

[0209] In addition, in ST43, the pumping flow control unit 515 can also limit or stop the operation of the submersible pump PP on the pumping well side to control the pumping flow from the pumping well.

[0210] On the other hand, the flow control unit 512 can also control the flow adjustment device 22 to reduce the flow rate FL and suppress the load on the heat source well equipment 10 by ensuring that the return water temperature of the heat source well equipment 10 is within the allowable value. Moreover, the flow control unit 512 can also control the auxiliary flow adjustment device 33 to increase the flow rate of the heat medium flowing between the auxiliary heat supply equipment 30 and the machine AA.

[0211] In ST41, if it is determined that the obtained pumping side water level is higher than the first limiting water level (ST41: Yes), it is determined whether the obtained pumping side water level is lower than the first release water level (e.g., 10m) (ST44). For example, the first release water level is a preset value.

[0212] Here, the first release water level is the water level at which the flow restriction on pumping should be lifted and the heat source machine 31 should be stopped when the water level is above this level.

[0213] In addition, in order to create a lag between the start-up and stop conditions of the heat source machine 31, the first release water level is set to be higher than the first limit water level.

[0214] In ST44, if it is determined that the obtained pumping water level is lower than the first release water level (ST44: Yes), the pumping restriction should not be released, and the control device 50 returns to the implementation of ST41.

[0215] In ST44, if it is not determined that the obtained pumping water level is lower than the first release water level (determined to be above the first release water level) (ST44: No), it is assumed that there is a possibility that the pumping restriction can be lifted, and the heat source machine control unit 513 determines whether there is a heat source machine 31 (other than the heat source machine included in the heat source well equipment 10) that is running (ST45).

[0216] In ST45, if it is determined that a heat source machine 31 is in operation (ST45: Yes), the heat source machine control unit 513 stops the heat source machine 31 in operation (ST46), and the control device 50 returns to the execution of ST41. At this time, the pumping flow control unit 515 can also control the flow by releasing the restriction imposed on the capacity of the submersible pump PP on the pumping well side or starting the operation of the submersible pump PP on the pumping well side to increase the pumping flow from the pumping well.

[0217] On the other hand, the flow control unit 512 can also control the flow adjustment device 22 to increase the flow rate FL, and control the auxiliary flow adjustment device 33 to reduce the flow rate of the heat medium flowing between the auxiliary heat supply device 30 and the machine AA.

[0218] In ST45, if it is determined that there is no heat source machine 31 in operation (ST45: No), the control device 50 returns to the implementation of ST41.

[0219] In ST42, if it is determined that there is no heat source machine 31 that can be started (ST42: No), the control device 50 stops the heat supply from the geothermal utilization system 1 to the machine AA (ST47). Afterwards, the users and others study the maintenance of various devices on the pumping well side, such as removing the blockage of the screen of the pumping well.

[0220] (The action of controlling the water level in the return water well)

[0221] The procedure for controlling the water level in the return water well is explained.

[0222] When geothermal utilization system 1 is started, such as Figure 9 As shown, the return water level acquisition unit 516 acquires the measurement result of the water level gauge 16 on the return water well side as the return water level, and determines whether the acquired return water level is lower than the second limit water level (e.g., 25m) (ST61). For example, the second limit water level is a preset value.

[0223] Here, the second limiting water level is the water level at which the flow of return water should be restricted and the heat source machine 31 should be activated when the water level is above this level.

[0224] It should be noted that in this water level control during refrigeration operation, the return water well is the warm water well 11, and the pumping water well is the cold water well 12.

[0225] On the other hand, in the water level control during heating operation, the return water well is the cold water well 12, and the pumping water well is the warm water well 11.

[0226] In ST61, if it is determined that the obtained return water level is not lower than the second limit water level (determined to be above the second limit water level) (ST61: No), the heat source control unit 513 determines whether there is a heat source 31 that can be started (other heat source) among the multiple heat source units 31 (ST62).

[0227] In ST62, if it is determined that there is a startable heat source 31 (ST62: Yes), the heat source control unit 513 starts the startable heat source 31 (ST63), and the control device 50 returns to the execution of ST61.

[0228] For example, in ST63, the heat source control unit 513 first starts one (configurable and changeable) heat source 31 that can be started. If multiple heat source 31s can be started, the heat source control unit 513 can perform increase / decrease segment control by repeatedly performing ST61 to ST63. At this time, the heat source control unit 513 can also observe the heat or flow rate supplied to machine AA and perform increase / decrease segment control accordingly.

[0229] In addition, in ST63, the return water flow control unit 517 can also limit or stop the operation of the submersible pump PP on the pumping well side to control the return water flow to the return water well.

[0230] On the other hand, the flow control unit 512 can also control the flow adjustment device 22 to reduce the flow rate FL and suppress the load on the heat source well equipment 10 by ensuring that the return water temperature of the heat source well equipment 10 is within the allowable value. Moreover, the flow control unit 512 can also control the auxiliary flow adjustment device 33 to increase the flow rate of the heat medium flowing between the auxiliary heat supply equipment 30 and the machine AA.

[0231] In ST61, if it is determined that the obtained return water level is lower than the second limit water level (ST61: Yes), it is determined whether the obtained return water level is higher than the second release water level (e.g., 21m) (ST64). For example, the second release water level is a preset value.

[0232] Here, the second release water level is the water level at which the flow restriction on the return water should be lifted and the heat source machine 31 should be stopped if it falls below this water level.

[0233] In addition, in order to create a lag between the start-up and stop conditions of the heat source machine 31, the second release water level is set to be lower than the second limit water level.

[0234] In ST64, if it is determined that the obtained return water level is higher than the second release water level (ST64: Yes), the return water restriction should not be released yet, and the control device 50 returns to the implementation of ST61.

[0235] In ST64, if it is not determined that the obtained return water level is higher than the second release water level (determined to be below the second release water level) (ST64: No), it is assumed that there is a possibility that the return water restriction can be lifted, and the heat source machine control unit 513 determines whether there is a heat source machine 31 (other than the heat source machine included in the heat source well equipment 10) that is running (ST65).

[0236] In ST65, if it is determined that a heat source machine 31 is in operation (ST65: Yes), the heat source machine control unit 513 stops the heat source machine 31 in operation (ST66), and the control device 50 returns to the execution of ST61. At this time, the return water flow control unit 517 can also control the flow by increasing the return water flow to the return water well by releasing the restriction imposed on the capacity of the submersible pump PP on the pumping well side or by starting the operation of the submersible pump PP on the pumping well side.

[0237] On the other hand, the flow control unit 512 can also control the flow adjustment device 22 to increase the flow rate FL, and control the auxiliary flow adjustment device 33 to reduce the flow rate of the heat medium flowing between the auxiliary heat supply device 30 and the machine AA.

[0238] In ST65, if it is determined that there is no heat source machine 31 in operation (ST65: No), the control device 50 returns to the implementation of ST61.

[0239] In ST62, if it is determined that there is no heat source machine 31 that can be started (ST62: No), the control device 50 stops the heat supply from the geothermal utilization system 1 to the machine AA (ST67). Afterwards, the users and others study the maintenance of various devices on the return water well side, such as removing the blockage of the filter screen of the return water well.

[0240] (Function and Effect)

[0241] According to this embodiment, the control device 50 controls the flow rate FL based on the return water temperature.

[0242] Therefore, when the load heat required by machine AA is large, the control device 50 can limit the heat discharge from machine AA to heat source well equipment 10.

[0243] Therefore, regardless of the heat load required by machine AA, control device 50 can adjust the temperature of groundwater to a temperature that is unlikely to affect the underground environment and return it to the return well.

[0244] Therefore, the control device 50 is unlikely to have an impact on the underground environment.

[0245] As a comparative example, in the geothermal utilization system disclosed in Patent Document 1, the return water temperature is controlled by controlling the flow rate from the pumping well to the return water well. In such a comparative example of geothermal utilization system, given the same amount of heat discharged from the machine to the aquifer, the temperature difference between the pumping temperature and the injection temperature is determined by the pumping temperature and the set return water temperature; therefore, only the flow rate is a variable value.

[0246] Therefore, in the comparative example geothermal utilization system, the pumping rate has an upper limit depending on the well performance. Thus, even if the pumping rate is maximized, the return water temperature will eventually exceed the upper limit (lower limit) when the heat load required by the machine is large.

[0247] Furthermore, in the comparative example geothermal utilization system, at the end of summer and winter, the heat accumulated in the previous seasons is consumed, and the groundwater temperature approaches the initial groundwater temperature, reducing the usable temperature difference. Therefore, when the equipment is under high load, the return water temperature is prone to exceeding the upper limit (lower limit).

[0248] On the other hand, in geothermal utilization systems, the return water temperature is ideally set to a temperature that does not easily cause changes in the water quality of the aquifer. For example, the return water temperature is ideally set to a temperature that does not easily cause changes in the microbial community structure.

[0249] However, in the comparative example geothermal utilization system, the return water temperature sometimes exceeds the upper limit (lower limit), which can easily cause changes in the water quality of the aquifer.

[0250] In contrast, as described above, the control device 50 controls the flow rate FL based on the return water temperature. Therefore, regardless of the load heat required by the machine AA, the control device 50 can adjust the temperature of the groundwater to a temperature that is not likely to affect the underground environment and return it to the return water well.

[0251] Therefore, the control device 50 is unlikely to cause changes in the water quality of the aquifer.

[0252] According to this embodiment, the control device 50 controls the start and stop of the heat source machine 31 based on the return water temperature, so that the heat source machine 31 can be started and stopped according to the load heat required by the machine AA.

[0253] Therefore, when the load heat required by machine AA is large, the control device 50 can enable the heat source well equipment 10 and the auxiliary heat supply equipment 30 to share the load heat required by machine AA.

[0254] Therefore, regardless of the heat load required by machine AA, control device 50 can adjust the temperature of groundwater to a temperature that is unlikely to affect the underground environment and return it to the return well.

[0255] Therefore, the control device 50 is unlikely to have an impact on the underground environment.

[0256] For example, control device 50 controls the start and stop of heat source unit 31 based on return water temperature, thereby... Figure 10 As shown, the heat source well equipment 10 and the auxiliary heat supply equipment 30 can share the load heat required by the machine AA.

[0257] Therefore, the control device 50 basically uses the high-efficiency heat source well equipment 10 to start the heat source machine 31, which is separate from the heat source well equipment 10, to distribute the load even when the pumping volume is maximized and the return water temperature still exceeds the upper limit. This allows the heat discharged to the aquifer LY to be controlled (limited).

[0258] Therefore, as described above, the control device 50 controls the start and stop of the heat source machine 31 based on the return water temperature. Thus, regardless of the load heat required by the machine AA, the control device 50 can adjust the temperature of the groundwater to a temperature that is not likely to affect the underground environment and return it to the return water well.

[0259] Therefore, the control device 50 is unlikely to cause changes in the water quality of the aquifer.

[0260] According to this embodiment, when the geothermal utilization system 1 is cooling the machine AA, the first stop temperature at which the heat source machine 31 should be stopped is lower than the first start temperature at which the heat source machine 31 should be started. Therefore, the control device 50 can make the start-up conditions and stop conditions of the heat source machine 31 lag.

[0261] For example, such as Figure 11 As shown, the control device 50 can make the start-up and stop conditions of the heat source machine 31 have a lag.

[0262] Thus, the control device 50 can, for example, suppress the oscillating action of the heat source machine 31 during startup and shutdown.

[0263] Therefore, the control device 50 can stabilize the operation of the heat source machine 31.

[0264] According to this embodiment, when the geothermal utilization system 1 is operating the machine AA for heating, the second stop temperature at which the heat source machine 31 should be stopped is higher than the second start temperature at which the heat source machine 31 should be started. Therefore, the control device 50 can make the start-up conditions and stop conditions of the heat source machine 31 lag.

[0265] Thus, the control device 50 can, for example, suppress the oscillating action of the heat source machine 31 during startup and shutdown.

[0266] Therefore, the control device 50 can stabilize the operation of the heat source machine 31.

[0267] According to this embodiment, the heat source control unit 513 can start a number of heat source machines 31 corresponding to the load heat shared by the auxiliary heat supply equipment in the load heat required by machine AA by performing increase / decrease segment control.

[0268] Therefore, the control device 50 can effectively utilize multiple heat sources 31.

[0269] According to this embodiment, the pumping flow control unit 515 controls the pumping flow based on the water level on the pumping side.

[0270] Thus, the control device 50 can, for example, limit water level fluctuations in the pumping well caused by factors such as clogging of the screen.

[0271] Therefore, the control device 50 can, for example, suppress malfunctions in the pumping well caused by the dry running of the submersible pump PP, and the development of blockages in the pumping well.

[0272] Therefore, the control device 50 can be used for a long time in the geothermal utilization system 1.

[0273] According to this embodiment, the heat source control unit 513 controls the start and stop of the heat source 31 based on the water level on the pumping side.

[0274] Therefore, the control device 50 can determine the load heat required by the pumping side water level auxiliary machine AA.

[0275] Therefore, even if the heat source well equipment 10 alone cannot bear the load heat required by the machine AA in order to maintain the water level on the pumping side, the control device 50 can enable the heat source well equipment 10 and the auxiliary heat supply equipment 30 to share the load heat required by the machine AA.

[0276] Therefore, the control device 50 can control the geothermal utilization system 1 in a manner that can supply the load heat required by the machine AA.

[0277] As a comparative example, in the geothermal utilization system disclosed in Patent Document 1, if the pumping rate exceeds the performance of the heat source well, the water level on the pumping side will drop more significantly, and sometimes blockages may occur due to the dry running of the submersible pump PP and the increased flow velocity through the screen on the pumping side.

[0278] For example, when constructing a heat source well, the upper limit of the pumping volume is determined through pumping tests, but due to years of deterioration such as screen blockage, the water level can sometimes fluctuate more even with the same pumping volume. Therefore, it is desirable to limit the pumping volume based on the water level and to make effective use of other heat sources.

[0279] On the other hand, for example, by basically using the high-efficiency heat source well equipment 10, if the water level on the pumping side drops below a set value, the control device 50 can control the pumping flow rate and start the heat source machine 31, which is separate from the heat source well equipment 10, to distribute the load.

[0280] Therefore, according to the control device 50, the pumping volume can be limited and other heat sources can be effectively utilized based on the water level on the pumping side.

[0281] According to this embodiment, the first release water level at which the flow restriction of the pumping should be lifted and the heat source machine 31 should be stopped is higher than the first restriction water level at which the flow restriction of the pumping should be lifted and the heat source machine 31 should be started. Therefore, the control device 50 can make the start-up condition and the stop condition of the heat source machine 31 have a lag.

[0282] For example, such as Figure 12 As shown, the control device 50 can make the start-up and stop conditions of the heat source machine 31 have a lag.

[0283] Thus, the control device 50 can, for example, suppress the oscillating action of the heat source machine 31 during startup and shutdown.

[0284] Therefore, the control device 50 can stabilize the operation of the heat source machine 31.

[0285] According to this embodiment, the pumping flow control unit 515 controls the return water flow based on the return water level.

[0286] Thus, the control device 50 can, for example, limit water level fluctuations in the return water well caused by factors such as clogging of the screen in the return water well.

[0287] Therefore, the control device 50 can, for example, suppress the development of blockage in the return water well.

[0288] Therefore, the control device 50 can be used for a long time in the geothermal utilization system 1.

[0289] According to this embodiment, the heat source control unit 513 controls the start and stop of the heat source 31 based on the return water level.

[0290] Therefore, the control device 50 can adjust the load heat required by the auxiliary machine AA based on the return water level.

[0291] Therefore, even if the heat source well equipment 10 alone cannot bear the load heat required by the machine AA in order to maintain the return water level, the control device 50 can enable the heat source well equipment 10 and the auxiliary heat supply equipment 30 to share the load heat required by the machine AA.

[0292] Therefore, the control device 50 can control the geothermal utilization system 1 in a manner that can supply the load heat required by the machine AA.

[0293] As a comparative example, in the geothermal utilization system disclosed in Patent Document 1, if water is injected at a return water volume exceeding the performance of the heat source well, the water level in the return water well will rise significantly, and sometimes blockages may occur due to the increased flow velocity through the screen in the return water well.

[0294] For example, when constructing a heat source well, the upper limit of the return water volume is determined through return water tests, but due to years of deterioration such as screen blockage, the water level can sometimes fluctuate more even for the same return water volume. Therefore, it is desirable to limit the return water volume based on the water level and to make effective use of other heat sources.

[0295] On the other hand, for example, by basically using a high-efficiency heat source well equipment 10, if the water level in the return water well rises above a set value, the control device 50 can control the return water flow and start the heat source machine 31, which is separate from the heat source well equipment 10, to distribute the load.

[0296] Therefore, according to the control device 50, the amount of return water can be limited and other heat sources can be effectively utilized based on the water level on the return water side.

[0297] According to this embodiment, the second release water level at which the flow restriction of the return water should be lifted and the heat source machine 31 should be stopped is lower than the second restriction water level at which the flow restriction of the return water should be lifted and the heat source machine 31 should be started. Therefore, the control device 50 can make the start-up condition and the stop condition of the heat source machine 31 have a lag.

[0298] Thus, the control device 50 can, for example, suppress the oscillating action of the heat source machine 31 during startup and shutdown.

[0299] Therefore, the control device 50 can stabilize the operation of the heat source machine 31.

[0300] According to this embodiment, the control device 50 is combined with the heat source well equipment 10 and the auxiliary heat supply equipment 30.

[0301] Therefore, the heat source well equipment 10 is a device that uses the aquifer LY as a natural heat storage tank. Since it utilizes nature, unpredictable situations may occur. According to the control device 50, the auxiliary heat supply equipment 30 becomes a backup for the heat source well equipment 10.

[0302] According to the control device 50 of this embodiment, automatic control of return water temperature management is easy to perform, thus user-side management becomes easy, and a universal system that can easily utilize geothermal energy can be built.

[0303] <Variation Example>

[0304] In one example of the above implementation, the control device 50 controls both the flow rate FL and the start and stop of the heat source machine 31 based on the return water temperature, but as long as the return water temperature can be controlled, the control can be performed arbitrarily.

[0305] As a variation, as long as the control device 50 can control the return water temperature, it can also control at least one of the following: the flow rate FL and the start and stop of the heat source unit 31, based on the return water temperature. In this case, the geothermal utilization system 1 can also include at least one of the following configurations: the flow rate adjustment device 22 and the auxiliary heat supply equipment 30.

[0306] In one example of the above-described implementation, the auxiliary heat supply device 30 includes a plurality of heat source machines 31, but any device may be included as long as it can assist the heat source well device 10 in supplying at least one of the warm or cold heat to the machine AA.

[0307] As a variation, the auxiliary heat supply equipment 30 may also have one heat source unit 31 instead of multiple heat source units 31.

[0308] As another variation, the auxiliary heat supply equipment 30 may replace multiple heat source units 31 or have a cooling tower on the basis of multiple heat source units 31.

[0309] In one example of the above-described implementation, the auxiliary heat supply device 30 includes a plurality of heat source machines 31, but any device may be included as long as it can assist the heat source well device 10 in supplying at least one of the warm or cold heat to the machine AA.

[0310] As a variation, the auxiliary heat supply equipment 30 may also have one heat source unit 31 instead of multiple heat source units 31.

[0311] As another variation, the auxiliary heat supply equipment 30 may replace multiple heat source units 31 or have a cooling tower on the basis of multiple heat source units 31.

[0312] In one example of the above-described implementation, the geothermal utilization circuit 20 includes a heat pump 21, but it can be configured arbitrarily as long as the mediation and control of heat reception between the heat exchanger 14 and the machine AA can be performed.

[0313] As a variation, the geothermal utilization circuit 20 may also include a flow adjustment device 22 and a main piping 23, but without a heat pump 21. In this case, the flow adjustment device 22 can also adjust the flow rate of the heat medium flowing directly from the machine AA side of the heat exchanger 14 to the machine AA.

[0314] In one example of the above implementation method, an upper limit (lower limit) of the return water temperature is preset, but it can be set arbitrarily as long as it can be controlled to a return water temperature that does not easily affect the underground environment.

[0315] As a variation, the upper limit (lower limit) of the return water temperature depends on the initial groundwater temperature of the area where the geothermal utilization system 1 is installed. Therefore, in the control device 50, the upper limit (lower limit) of the return water temperature is not particularly limited and can be updated to a value that can be set appropriately.

[0316] In one example of the above implementation, the flow control unit 512 controls the bypass valve 223, but arbitrary control can also be performed as long as the flow rate FL can be controlled.

[0317] As a variation, the flow control unit 512 can also control the flow rate FL by performing inverter control of the pump 221 and opening control of the electric valve 222, based on or replacing the control of the bypass valve 223.

[0318] Furthermore, the flow control unit 512 can also control the opening degree of the bypass valve of the auxiliary flow adjustment device 33, the inverter control of the pump of the auxiliary flow adjustment device 33, and the opening degree of the electric valve of the auxiliary flow adjustment device 33 in the same way as the control of the flow adjustment device 22, so as to adjust the flow rate of the medium flowing from the auxiliary heat supply equipment 30 to the machine AA.

[0319] It should be noted that in the above embodiments, programs for implementing various functions of the control device 50 are recorded on a computer-readable recording medium. The programs recorded on this recording medium are read into the computer system and executed, thereby performing various processes. Here, the various processing procedures of the CPU 51 of the computer system are stored in the form of a program on the computer-readable recording medium. The computer reads and executes this program, thereby performing the aforementioned various processes. Furthermore, a computer-readable recording medium refers to a magnetic disk, optical disk, CD-ROM (Compact Disc Read-Only Memory), DVD-ROM (Digital Video Disc Read Only Memory), semiconductor memory, etc. Alternatively, the computer program can be transmitted to a computer via a communication line, etc., and the computer receiving the transmission can execute the program.

[0320] <Other Implementation Methods>

[0321] The embodiments of this disclosure have been described above, but these embodiments are shown as examples and are not intended to limit the scope of this disclosure. This disclosure can be implemented in various other ways, and various omissions, substitutions, and modifications can be made without departing from the spirit of this disclosure. This disclosure and its variations are included within the scope and spirit of this disclosure, as well as within the scope of this disclosure and its equivalents.

[0322] <Postscript>

[0323] For example, the control device 50, geothermal utilization system 1, control method and program described in the above-described implementation method are as follows.

[0324] (1) The control device 50 of the first scheme includes: a return water temperature acquisition unit 511, which acquires the return water temperature of the geothermal utilization system 1 to the return water well (warm water well 11 or cold water well 12), the geothermal utilization system 1 includes a heat source well device 10 and a geothermal utilization circuit 20, the heat source well device 10 includes a pumping well (cold water well 12 or warm water well 11), the return water well (warm water well 11 or cold water well 12), a well-side pipe 13 extending from the pumping well (cold water well 12 or warm water well 11) to the return water well (warm water well 11 or cold water well 12), and a heat exchanger 14 located in the middle of the well-side pipe 13, the geothermal utilization circuit 20 being located between the heat exchanger 14 and the machine AA; and a flow control unit 512, which controls the flow rate FL of the refrigerant flowing from the geothermal utilization circuit 20 to the machine AA based on the return water temperature.

[0325] According to this scheme, the control device 50 controls the flow rate FL based on the return water temperature.

[0326] Therefore, when the load heat required by machine AA is large, the control device 50 can limit the heat discharge from machine AA to heat source well equipment 10.

[0327] Therefore, regardless of the heat load required by machine AA, control device 50 can adjust the temperature of groundwater to a temperature that is not likely to affect the underground environment and return it to the return well (warm water well 11 or cold water well 12).

[0328] Therefore, the control device 50 is unlikely to have an impact on the underground environment.

[0329] (2) The control device 50 of the second scheme is the control device 50 of (1), wherein the control device 50 further includes an auxiliary heat supply device 30, the auxiliary heat supply device 30 is connected in parallel with the geothermal utilization circuit 20 in the machine AA and includes a heat source machine 31, the control device 50 further includes a heat source machine control unit 513, the heat source machine control unit 310 controls the start and stop of the heat source machine 31 based on the return water temperature.

[0330] According to this scheme, the control device 50 can start and stop the heat source machine 31 according to the load heat required by the machine AA.

[0331] Therefore, when the load heat required by machine AA is large, the control device 50 can enable the heat source well equipment 10 and the auxiliary heat supply equipment 30 to share the load heat required by machine AA.

[0332] Therefore, regardless of the heat load required by machine AA, control device 50 can adjust the temperature of groundwater to a temperature that is not likely to affect the underground environment and return it to the return well (warm water well 11 or cold water well 12).

[0333] Therefore, the control device 50 is unlikely to have an impact on the underground environment.

[0334] (3) The control device 50 of the third scheme is the control device 50 of (2), wherein when the geothermal utilization system 1 performs cooling operation on the machine AA, the first stop temperature at which the stop should be performed is lower than the first start temperature at which the start should be performed.

[0335] According to this scheme, the control device 50 can make the start-up and stop conditions of the heat source machine 31 have a lag.

[0336] Thus, the control device 50 can, for example, suppress the oscillating action of the heat source machine 31 during startup and shutdown.

[0337] Therefore, the control device 50 can stabilize the operation of the heat source machine 31.

[0338] (4) The control device 50 of the fourth scheme is the control device 50 of (2) or (3), wherein when the geothermal utilization system heats the machine AA, the second stop temperature at which the stop should be performed is higher than the second start temperature at which the start should be performed.

[0339] According to this scheme, the start-up and stop conditions of machine AA can be made to have a lag.

[0340] Thus, the control device 50 can, for example, suppress the oscillating motion of the machine AA during startup and shutdown.

[0341] Therefore, the control device 50 can stabilize the operation of the heat source machine 31.

[0342] (5) The control device 50 of the fifth scheme is any one of (2) to (4), wherein the heat source machine 31 has multiple heat source machines 31, and the heat source machine control unit 513 performs the increase and decrease segment control of the multiple heat source machines 31.

[0343] According to this scheme, the control device 50 can start a number of heat source machines 31 corresponding to the load heat shared by the auxiliary heat supply equipment 30 in the load heat required by machine AA.

[0344] Therefore, the control device 50 can effectively utilize multiple heat source units 31.

[0345] (6) The control device 50 of the sixth scheme is the control device 50 of (1), wherein the control device 50 further comprises: a pumping side water level acquisition unit 514, which acquires the pumping side water level as the water level of the pumping well (cold water well 12 or warm water well 11); and a pumping flow control unit 515, which controls the pumping flow from the pumping well (cold water well 12 or warm water well 11) based on the pumping side water level.

[0346] According to this scheme, the control device 50 controls the pumping flow rate based on the water level on the pumping side.

[0347] Thus, the control device 50 can, for example, limit the water level fluctuation of the pumping well (cold water well 12 or warm water well 11) caused by the clogging of the screen of the pumping well (cold water well 12 or warm water well 11).

[0348] Therefore, the control device 50 can, for example, suppress malfunctions in the pumping well (cold water well 12 or warm water well 11) caused by the dry running of the submersible pump PP, and the development of blockages in the pumping well (cold water well 12 or warm water well 11).

[0349] Therefore, the control device 50 can be used for a long time in the geothermal utilization system 1.

[0350] (7) The control device 50 of the seventh scheme is the control device 50 of (6), wherein the geothermal utilization system also includes an auxiliary heat supply device 30, the auxiliary heat supply device 30 is connected in parallel with the geothermal utilization circuit 20 in the machine and includes a heat source machine 31, the control device 50 also includes a heat source machine control unit 513, the heat source machine control unit 513 controls the start and stop of the heat source machine 31 based on the water level on the pumping side.

[0351] According to this scheme, the control device 50 can be based on the load heat required by the pumping side water level auxiliary machine AA.

[0352] Therefore, even if the heat source well equipment 10 alone cannot bear the load heat required by the machine AA in order to maintain the water level on the pumping side, the control device 50 can enable the heat source well equipment 10 and the auxiliary heat supply equipment 30 to share the load heat required by the machine AA.

[0353] Therefore, the control device 50 can control the geothermal utilization system 1 in a manner that can supply the load heat required by the machine AA.

[0354] (8) The control device 50 of the eighth scheme is the control device 50 of (1), wherein the control device 50 further comprises: a return water side water level acquisition unit 516, which acquires the return water side water level as the water level of the return water well (warm water well 11 or cold water well 12); and a return water flow control unit 517, which controls the return water flow to the return water well (warm water well 11 or cold water well 12) based on the return water side water level.

[0355] According to this scheme, the pumping flow control unit 515 controls the return water flow based on the return water level.

[0356] Thus, the control device 50 can, for example, limit the water level fluctuation of the return water well (warm water well 11 or cold water well 12) caused by factors such as blockage of the screen of the return water well (warm water well 11 or cold water well 12).

[0357] Therefore, the control device 50 can, for example, suppress the development of blockage in the return water well (warm water well 11 or cold water well 12).

[0358] Therefore, the control device 50 can be used for a long time in the geothermal utilization system 1.

[0359] (9) The control device 50 of the ninth scheme is the control device 50 of (8), wherein the geothermal utilization system 1 further includes an auxiliary heat supply device 30, the auxiliary heat supply device 30 is connected in parallel with the geothermal utilization circuit 20 in the machine AA and includes a heat source machine 31, the control device 50 further includes a heat source machine control unit 513, the heat source machine control unit 513 controls the start and stop of the heat source machine 31 based on the return water level.

[0360] According to this scheme, the control device 50 can assist the machine AA with the required load heat based on the return water level.

[0361] Therefore, even if the heat source well equipment 10 alone cannot bear the load heat required by the machine AA in order to maintain the return water level, the control device 50 can enable the heat source well equipment 10 and the auxiliary heat supply equipment 30 to share the load heat required by the machine AA.

[0362] Therefore, the control device 50 can control the geothermal utilization system 1 in a manner that can supply the load heat required by the machine AA.

[0363] (10) The control device 50 of the tenth embodiment includes: a return water temperature acquisition unit 511, which acquires the return water temperature of the geothermal utilization system 1 to the return water well (warm water well 11 or cold water well 12). The geothermal utilization system 1 includes a heat source well device 10, a geothermal utilization circuit 20, and an auxiliary heat supply device 30. The heat source well device 10 includes a pumping well (cold water well 12 or warm water well 11), the return water well (warm water well 11 or cold water well 12), and a pumping well (cold water well 12 or cold water well 12). The well-side piping 13 extends from the warm water well 11 to the return water well (warm water well 11 or cold water well 12) and a heat exchanger 14 is located in the middle of the well-side piping 13. The geothermal utilization circuit 20 is located between the heat exchanger 14 and the machine AA. The auxiliary heat supply equipment 30 is connected in parallel with the geothermal utilization circuit 20 in the machine and has a heat source machine 31; and a heat source machine control unit 513, which controls the start and stop of the heat source machine 31 based on the return water temperature.

[0364] According to this scheme, the control device 50 can start and stop the heat source machine 31 according to the load heat required by the machine AA.

[0365] Therefore, when the load heat required by machine AA is large, the control device 50 can enable the heat source well equipment 10 and the auxiliary heat supply equipment 30 to share the load heat required by machine AA.

[0366] Therefore, regardless of the heat load required by machine AA, control device 50 can adjust the temperature of groundwater to a temperature that is not likely to affect the underground environment and return it to the return well (warm water well 11 or cold water well 12).

[0367] Therefore, the control device 50 is unlikely to have an impact on the underground environment.

[0368] (11) The geothermal utilization system 1 of the eleventh scheme comprises: a control device 50 as described in any one of (1) to (10); the heat source well equipment 10; and the geothermal utilization circuit 20.

[0369] According to this scheme, the flow rate FL of the geothermal utilization system 1 is controlled based on the return water temperature.

[0370] Therefore, when the load heat required by the machine AA is large, the geothermal utilization system 1 can limit the heat discharge from the machine AA to the heat source well equipment 10.

[0371] Therefore, regardless of the heat load required by machine AA, geothermal utilization system 1 can adjust the temperature of groundwater to a temperature that is not likely to affect the underground environment and return it to the return water well (warm water well 11 or cold water well 12).

[0372] Therefore, geothermal utilization system 1 is unlikely to have an impact on the underground environment.

[0373] (12) The control method of the twelfth scheme performs the following processing: obtaining the return water temperature of the geothermal utilization system 1 to the return water well (warm water well 11 or cold water well 12), the geothermal utilization system 1 having a heat source well device 10 and a geothermal utilization circuit 20, the heat source well device 10 having a pumping well (cold water well 12 or warm water well 11), the return water well (warm water well 11 or cold water well 12), a well-side pipe 13 extending from the pumping well (cold water well 12 or warm water well 11) to the return water well (warm water well 11 or cold water well 12), and a heat exchanger 14 located in the middle of the well-side pipe 13, the geothermal utilization circuit 20 being located between the heat exchanger 14 and the machine AA; and controlling the flow rate FL of the refrigerant flowing from the geothermal utilization circuit 20 to the machine AA based on the return water temperature.

[0374] According to this scheme, the control method is based on controlling the flow rate FL according to the return water temperature.

[0375] Therefore, the control method can limit the heat dissipation from machine AA to heat source well equipment 10 when the load heat required by machine AA is large.

[0376] Therefore, regardless of the heat load required by machine AA, the control method can adjust the temperature of the groundwater to a temperature that is not likely to affect the underground environment and return it to the return well (warm water well 11 or cold water well 12).

[0377] Therefore, the control methods are unlikely to have an impact on the underground environment.

[0378] (13) The control method of the thirteenth scheme performs the following processing: obtaining the return water temperature of the geothermal utilization system 1 to the return water well (warm water well 11 or cold water well 12), the geothermal utilization system 1 having a heat source well device 10, a geothermal utilization circuit 20 and an auxiliary heat supply device 30, the heat source well device 10 having a pumping well (cold water well 12 or warm water well 11), the return water well (warm water well 11 or cold water well 12), a well-side pipe 13 extending from the pumping well (cold water well 12 or warm water well 11) to the return water well (warm water well 11 or cold water well 12) and a heat exchanger 14 located in the middle of the well-side pipe 13, the geothermal utilization circuit 20 being located between the heat exchanger 14 and the machine AA, the auxiliary heat supply device 30 being located in parallel with the geothermal utilization circuit 20 in the machine AA and having a heat source machine 31; and controlling the start and stop of the heat source machine 31 based on the return water temperature.

[0379] According to this scheme, the control method can start and stop the heat source machine 31 according to the load heat required by machine AA.

[0380] Therefore, when the load heat required by machine AA is large, the control method can enable the heat source well equipment 10 and the auxiliary heat supply equipment 30 to share the load heat required by machine AA.

[0381] Therefore, regardless of the heat load required by machine AA, the control method can adjust the temperature of the groundwater to a temperature that is not likely to affect the underground environment and return it to the return well (warm water well 11 or cold water well 12).

[0382] Therefore, the control methods are unlikely to have an impact on the underground environment.

[0383] (14) The procedure of the fourteenth scheme causes the computer to perform the following processing: obtain the return water temperature of the geothermal utilization system 1 to the return water well (warm water well 11 or cold water well 12), the geothermal utilization system 1 having a heat source well device 10 and a geothermal utilization circuit 20, the heat source well device 10 having a pumping well (cold water well 12 or warm water well 11), the return water well (warm water well 11 or cold water well 12), a well-side piping 13 extending from the pumping well (cold water well 12 or warm water well 11) to the return water well (warm water well 11 or cold water well 12), and a heat exchanger 14 located in the middle of the well-side piping 13, the geothermal utilization circuit 20 being located between the heat exchanger 14 and the machine AA; and based on the return water temperature, control the flow rate FL of the refrigerant flowing from the geothermal utilization circuit 20 to the machine AA.

[0384] According to this scheme, the program controls the flow rate FL based on the return water temperature.

[0385] Therefore, when the load heat required by machine AA is large, the program can limit the heat discharge from machine AA to heat source well equipment 10.

[0386] Therefore, regardless of the heat load required by machine AA, the program can adjust the temperature of the groundwater to a temperature that is not likely to affect the underground environment and return it to the return well (warm water well 11 or cold water well 12).

[0387] Therefore, the procedure is unlikely to have an impact on the underground environment.

[0388] (15) The program of the fifteenth scheme causes the computer to perform the following processing: obtain the return water temperature of the geothermal utilization system 1 to the return water well (warm water well 11 or cold water well 12), the geothermal utilization system 1 having a heat source well device 10, a geothermal utilization circuit 20 and an auxiliary heat supply device 30, the heat source well device 10 having a pumping well (cold water well 12 or warm water well 11), the return water well (warm water well 11 or cold water well 12), a well-side piping 13 extending from the pumping well (cold water well 12 or warm water well 11) to the return water well (warm water well 11 or cold water well 12) and a heat exchanger 14 located in the middle of the well-side piping 13, the geothermal utilization circuit 20 being located between the heat exchanger 14 and the machine AA, the auxiliary heat supply device 30 being located in parallel with the geothermal utilization circuit 20 in the machine AA and having a heat source machine 31; and control the start and stop of the heat source machine based on the return water temperature.

[0389] According to this scheme, the program can start and stop the heat source machine 31 based on the load heat required by machine AA.

[0390] Therefore, when the load heat required by machine AA is large, the program can enable the heat source well equipment 10 and the auxiliary heat supply equipment 30 to share the load heat required by machine AA.

[0391] Therefore, regardless of the heat load required by machine AA, the program can adjust the temperature of the groundwater to a temperature that is not likely to affect the underground environment and return it to the return well (warm water well 11 or cold water well 12).

[0392] Therefore, the procedure is unlikely to have an impact on the underground environment.

[0393] Industrial availability

[0394] The control device, geothermal utilization system, control method, and procedure disclosed herein are unlikely to have an impact on the underground environment.

[0395] Explanation of reference numerals in the attached figures

[0396] 1: Geothermal utilization system;

[0397] 10: Heat source well equipment;

[0398] 11: Warm water well (return water well or pumping well);

[0399] 12: Cold water well (pumping well or return water well);

[0400] 13: Well side piping;

[0401] 14: Heat exchanger;

[0402] 15: Water thermometer;

[0403] 16: Water level gauge;

[0404] 20: Geothermal utilization loop;

[0405] 21: Heat pump;

[0406] 22: Flow adjustment device;

[0407] 23: Main piping;

[0408] 30: Auxiliary heat supply equipment;

[0409] 31: Heat source machine;

[0410] 32: Auxiliary piping;

[0411] 33: Auxiliary flow adjustment device;

[0412] 50: Control device;

[0413] 51: CPU;

[0414] 52: Memory;

[0415] 53: Communication interface;

[0416] 54: Recording medium;

[0417] 131: First end;

[0418] 132: Second end;

[0419] 221: Pump;

[0420] 222: Electric valve;

[0421] 223: Bypass valve;

[0422] 511: Return water temperature acquisition unit;

[0423] 512: Flow Control Department;

[0424] 513: Heat source control unit;

[0425] 514: Pumping side water level acquisition unit;

[0426] 515: Pumping flow control unit;

[0427] 516: Water level acquisition unit on the return water side;

[0428] 517: Return water flow control unit;

[0429] AA: Machine;

[0430] FL: Flow rate;

[0431] LY: Aquifer;

[0432] PP: Submersible pump;

[0433] VA: Water injection valve;

[0434] VB: Check valve.

Claims

1. A control device, the control device comprising: The return water temperature acquisition unit acquires the return water temperature of the geothermal utilization system to the return water well. The geothermal utilization system includes a heat source well device, a geothermal utilization circuit, and an auxiliary heat supply device. The heat source well device includes a pumping well, the return water well, a well-side piping extending from the pumping well to the return water well, and a heat exchanger located in the middle of the well-side piping. The geothermal utilization circuit is located between the heat exchanger and the machine. The auxiliary heat supply device is connected in parallel with the geothermal utilization circuit to the machine and includes a heat source unit. The flow control unit, based on the return water temperature, controls the flow rate of refrigerant from the geothermal utilization circuit to the machine; and The heat source control unit controls the start and stop of the heat source machine based on the return water temperature.

2. The control device according to claim 1, wherein, When the geothermal utilization system is operating the machine for cooling, the first stop temperature at which the machine should be stopped is lower than the first start temperature at which the machine should be started.

3. The control device according to claim 1, wherein, When the geothermal utilization system is operating the machine for heating, the second stop temperature at which the machine should be stopped is higher than the second start temperature at which the machine should be started.

4. The control device according to claim 1, wherein, The heat source unit has multiple heat source units. The heat source control unit performs the increase / decrease control of the multiple heat source units.

5. A control device, the control device comprising: A return water temperature acquisition unit acquires the return water temperature of the geothermal utilization system to the return water well. The geothermal utilization system includes a heat source well and a geothermal utilization circuit. The heat source well includes a pumping well, the return water well, well-side piping extending from the pumping well to the return water well, and a heat exchanger located midway along the well-side piping. The geothermal utilization circuit is located between the heat exchanger and the machine. The flow control unit, based on the return water temperature, controls the flow rate of refrigerant from the geothermal utilization circuit to the machine. The control device also includes: The pumping-side water level acquisition unit acquires the pumping-side water level, which is the water level of the pumping well; and The pumping flow control unit controls the pumping flow rate from the pumping well based on the water level on the pumping side.

6. The control device according to claim 5, wherein, The geothermal utilization system also includes auxiliary heat supply equipment, which is installed in parallel with the geothermal utilization circuit in the machine and includes a heat source unit. The control device also includes a heat source machine control unit, which controls the start and stop of the heat source machine based on the water level on the pumping side.

7. A control device, the control device comprising: A return water temperature acquisition unit acquires the return water temperature of the geothermal utilization system to the return water well. The geothermal utilization system includes a heat source well and a geothermal utilization circuit. The heat source well includes a pumping well, the return water well, well-side piping extending from the pumping well to the return water well, and a heat exchanger located midway along the well-side piping. The geothermal utilization circuit is located between the heat exchanger and the machine. The flow control unit, based on the return water temperature, controls the flow rate of refrigerant from the geothermal utilization circuit to the machine. The control device also includes: The return water level acquisition unit acquires the return water level, which is the water level of the return water well; and The return water flow control unit controls the return water flow rate to the return water well based on the water level on the return water side.

8. The control device according to claim 7, wherein, The geothermal utilization system also includes auxiliary heat supply equipment, which is installed in parallel with the geothermal utilization circuit in the machine and includes a heat source unit. The control device also includes a heat source machine control unit, which controls the start and stop of the heat source machine based on the return water level.

9. A geothermal utilization system, the geothermal utilization system comprising: The control device as described in any one of claims 1 to 8; The heat source well equipment; and The geothermal utilization circuit.

10. A control method, wherein the control method performs the following processing: The system obtains the return water temperature of the return water well of the geothermal utilization system. The geothermal utilization system includes a heat source well device, a geothermal utilization circuit, and an auxiliary heat supply device. The heat source well device includes a pumping well, the return water well, a well-side piping extending from the pumping well to the return water well, and a heat exchanger located in the middle of the well-side piping. The geothermal utilization circuit is located between the heat exchanger and the machine. The auxiliary heat supply device is located in parallel with the geothermal utilization circuit in the machine and includes a heat source unit. Based on the return water temperature, the flow rate of refrigerant from the geothermal utilization circuit to the machine is controlled; and The start and stop of the heat source machine are controlled based on the return water temperature.

11. A control method, wherein the control method performs the following processing: The temperature of the return water from the return water well of the geothermal utilization system is obtained. The geothermal utilization system includes a heat source well device and a geothermal utilization circuit. The heat source well device includes a pumping well, the return water well, a well-side piping extending from the pumping well to the return water well, and a heat exchanger located in the middle of the well-side piping. The geothermal utilization circuit is located between the heat exchanger and the machine. Based on the return water temperature, the flow rate of refrigerant from the geothermal utilization circuit to the machine is controlled; Obtain the pumping-side water level, which is the water level of the pumping well; and The pumping flow rate from the pumping well is controlled based on the water level on the pumping side.

12. A control method, wherein the control method performs the following processing: The temperature of the return water from the return water well of the geothermal utilization system is obtained. The geothermal utilization system includes a heat source well device and a geothermal utilization circuit. The heat source well device includes a pumping well, the return water well, a well-side piping extending from the pumping well to the return water well, and a heat exchanger located in the middle of the well-side piping. The geothermal utilization circuit is located between the heat exchanger and the machine. Based on the return water temperature, the flow rate of refrigerant from the geothermal utilization circuit to the machine is controlled; Obtain the return water level on the return water side, which serves as the water level of the return water well; and The return water flow rate to the return water well is controlled based on the return water level on the return water side.

13. A program that causes a computer to perform the following processes: The system obtains the return water temperature of the return water well of the geothermal utilization system. The geothermal utilization system includes a heat source well device, a geothermal utilization circuit, and an auxiliary heat supply device. The heat source well device includes a pumping well, the return water well, a well-side piping extending from the pumping well to the return water well, and a heat exchanger located in the middle of the well-side piping. The geothermal utilization circuit is located between the heat exchanger and the machine. The auxiliary heat supply device is located in parallel with the geothermal utilization circuit in the machine and includes a heat source unit. Based on the return water temperature, the flow rate of refrigerant from the geothermal utilization circuit to the machine is controlled; and The start and stop of the heat source machine are controlled based on the return water temperature.

14. A program that causes a computer to perform the following processes: The temperature of the return water from the return water well of the geothermal utilization system is obtained. The geothermal utilization system includes a heat source well device and a geothermal utilization circuit. The heat source well device includes a pumping well, the return water well, a well-side piping extending from the pumping well to the return water well, and a heat exchanger located in the middle of the well-side piping. The geothermal utilization circuit is located between the heat exchanger and the machine. Based on the return water temperature, the flow rate of refrigerant from the geothermal utilization circuit to the machine is controlled; Obtain the pumping-side water level, which is the water level of the pumping well; and The pumping flow rate from the pumping well is controlled based on the water level on the pumping side.

15. A program that causes a computer to perform the following processes: The temperature of the return water from the return water well of the geothermal utilization system is obtained. The geothermal utilization system includes a heat source well device and a geothermal utilization circuit. The heat source well device includes a pumping well, the return water well, a well-side piping extending from the pumping well to the return water well, and a heat exchanger located in the middle of the well-side piping. The geothermal utilization circuit is located between the heat exchanger and the machine. Based on the return water temperature, the flow rate of refrigerant from the geothermal utilization circuit to the machine is controlled; Obtain the return water level on the return water side, which serves as the water level of the return water well; and The return water flow rate to the return water well is controlled based on the return water level on the return water side.

Images