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

Abstract

A control device is provided with: a first mode control unit for controlling a geothermal energy utilization system, which is provided with a heat source well facility including a warm water well and a cold water well, and a heat storage assistance facility including a waste heat recovery mechanism, a cooling tower, or an air-cooled heat pump, in a first mode in which cold energy stored in the cold water well is supplied to a machine; heat energy obtained from the machine is accumulated in the warm water well; and a second mode control unit that, instead of the first mode, controls the geothermal energy utilization system in a second mode in which cold energy accumulated in the cold water well is supplied to the heat storage assistance equipment and heat energy obtained from the heat storage assistance equipment is accumulated in the warm water well.

Description

Technical Field

[0001] The present disclosure relates to a control device, a geothermal utilization system, a control method, and a program.

[0002] This application claims priority based on Japanese Patent Application No. 2022-184746 filed in Japan on November 18, 2022, and incorporates its content herein. Background Art

[0003] In recent years, a geothermal utilization system that utilizes heat stored underground has been proposed.

[0004] As a related technology, for example, in Patent Document 1, a geothermal utilization system that stores heat discharged from a building underground is disclosed.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2018-071949 Summary of the Invention

[0008] Problems to be Solved by the Invention

[0009] The geothermal utilization system disclosed in Patent Document 1 uses the thermal energy stored in the heat storage tank as a heat source for heating a building and a heat source for hot water, and uses the cold energy stored in another heat storage tank as a heat source for cooling the building.

[0010] However, for example, in cold regions and the like, when the thermal energy stored during the summer is small, the thermal energy stored during the winter may sometimes be insufficient.

[0011] An object of the present disclosure is to provide a control device, a geothermal utilization system, a control method, and a program in which the stored thermal energy is less likely to be insufficient.

[0012] Solutions to the Problems

[0013] To solve the above problems, the control device of the present disclosure includes: a first mode control unit that controls a geothermal utilization system in a first mode, the geothermal utilization system including a heat source well device including a warm water well and a cold water well, and a heat storage auxiliary device including a waste heat recovery mechanism, a cooling tower, or an air-cooled heat pump, and in the first mode, supplying the cold energy stored in the cold water well to a machine and storing the thermal energy obtained from the machine in the warm water well; and a second mode control unit that controls the geothermal utilization system in a second mode instead of the first mode, and in the second mode, supplying the cold energy stored in the cold water well to the heat storage auxiliary device and storing the thermal energy obtained from the heat storage auxiliary device in the warm water well.

[0014] The geothermal utilization system of the present disclosure includes the control device, the heat source well equipment, and the heat storage auxiliary equipment.

[0015] The control method of the present disclosure, wherein the geothermal utilization system is controlled in a first mode. The geothermal utilization system includes heat source well equipment including a warm water well and a cold water well, and a heat storage auxiliary equipment including a waste heat recovery mechanism, a cooling tower, or an air-cooled heat pump. In the first mode, the cold energy stored in the cold water well is supplied to a machine, and the heat energy obtained from the machine is stored in the warm water well; and the geothermal utilization system is controlled in a second mode instead of the first mode. In the second mode, the cold energy stored in the cold water well is supplied to the heat storage auxiliary equipment, and the heat energy obtained from the heat storage auxiliary equipment is stored in the warm water well.

[0016] The program of the present disclosure causes a computer to perform the following control: controlling the geothermal utilization system in a first mode. The geothermal utilization system includes heat source well equipment including a warm water well and a cold water well, and a heat storage auxiliary equipment including a waste heat recovery mechanism, a cooling tower, or an air-cooled heat pump. In the first mode, the cold energy stored in the cold water well is supplied to a machine, and the heat energy obtained from the machine is stored in the warm water well; and controlling the geothermal utilization system in a second mode instead of the first mode. In the second mode, the cold energy stored in the cold water well is supplied to the heat storage auxiliary equipment, and the heat energy obtained from the heat storage auxiliary equipment is stored in the warm water well.

[0017] Advantages of the Invention

[0018] According to the control device, the geothermal utilization system, the control method, and the program of the present disclosure, the stored heat energy is not likely to be insufficient. Brief Description of the Drawings

[0019] Figure 1 It is a schematic diagram of the geothermal utilization system according to an embodiment of the present disclosure.

[0020] Figure 2 It is a system diagram of the geothermal utilization system according to an embodiment of the present disclosure.

[0021] Figure 3 It is a block diagram of the control device according to an embodiment of the present disclosure.

[0022] Figure 4 It is a flowchart of the control method according to an embodiment of the present disclosure.

[0023] Figure 5 It is a diagram showing the operation of the first mode of the geothermal utilization system according to an embodiment of the present disclosure.

[0024] Figure 6This is a diagram showing the operation of the second mode (waste heat utilization mode) of the geothermal utilization system according to an embodiment of the present disclosure.

[0025] Figure 7 This is a diagram showing the operation of the second mode (cooling tower utilization mode) of the geothermal utilization system according to an embodiment of the present disclosure.

[0026] Figure 8 This is a diagram showing the operation of the second mode (air-cooled heat pump utilization mode) of the geothermal utilization system according to an embodiment of the present disclosure.

[0027] Figure 9 This is a diagram showing the operation of the third mode of the geothermal utilization system according to an embodiment of the present disclosure.

[0028] Figure 10 This is a diagram showing the operation of a modified example of the second mode (cooling tower utilization mode) of the geothermal utilization system according to an embodiment of the present disclosure.

[0029] Figure 11 This is a diagram showing the operation of a modified example of the second mode (air-cooled heat pump utilization mode) of the geothermal utilization system according to an embodiment of the present disclosure. Detailed Embodiments

[0030] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In all the drawings, the same or corresponding components are denoted by the same reference numerals and common descriptions are omitted.

[0031] <Embodiment>

[0032] Refer to Figures 1 to 9 An embodiment of the geothermal utilization system of the present disclosure will be described.

[0033] (Configuration of Geothermal Utilization System)

[0034] As Figure 1 and Figure 2 shown, the geothermal utilization system 1 includes a heat source well device 10, a heat storage auxiliary device 20, a heat pump 30, a heat exchanger 40, and a control device 50.

[0035] When heating is utilized in the machine AA (e.g., air conditioning load), the geothermal utilization system 1 uses the thermal energy stored as warm water in the heat source well device 10 for heating, and at the same time stores the cold energy waste heat from the machine AA as cold water in the heat source well device 10.

[0036] When cooling is utilized in the machine AA, the geothermal utilization system 1 uses the cold energy stored as cold water in the heat source well device 10 for cooling, and at the same time stores the thermal energy waste heat from the machine AA as warm water in the heat source well device 10.

[0037] (Configuration of Heat Source Well Device)

[0038] The heat source well device 10 includes a warm water well 11, a cold water well 12, and a pipe 13.

[0039] The warm water well 11 and the cold water well 12 extend from the ground into the aquifer LY respectively. The warm water well 11 and the cold water well 12 each include a casing with a screen and the like, and are configured to take in the groundwater in the aquifer LY, or return the groundwater from the inside of the warm water well 11 and the cold water well 12 to the aquifer LY.

[0040] During the steady-state operation of the geothermal utilization system 1, warm water is stored in the aquifer LY around the warm water well 11, and cold water is stored in the aquifer LY around the cold water well 12.

[0041] The warm water well 11 and the cold water well 12 are arranged at a distance sufficient to separate the stored warm water and cold water from mixing with each other.

[0042] In the geothermal utilization system 1, the heat source well device 10 pumps groundwater from one of the warm water well 11 and the cold water well 12 to the ground, performs heat exchange on the ground for heat utilization and auxiliary heat storage, and injects it into the other of the warm water well 11 and the cold water well 12. That is, the heat source well device 10 has two operating modes: an operating mode in which groundwater is pumped from the warm water well 11 and injected into the cold water well 12, and an operating mode in which groundwater is pumped from the cold water well 12 and injected into the warm water well 11.

[0043] The pipe 13 connects the warm water well 11 and the cold water well 12.

[0044] As Figure 1 shown, the first end 131, which is one end of the pipe 13, extends into the warm water well 11 and is immersed in the groundwater inside the warm water well 11.

[0045] The second end 132, which is the other end of the pipe 13, extends into the cold water well 12 and is immersed in the groundwater inside the cold water well 12.

[0046] A pump PP, an injection valve VA, a check valve VB, etc. are respectively provided at the first end 131 and the second end 132, and are configured to be able to pump water from each well into the pipe 13, or inject water from the pipe 13 into each well.

[0047] The pump PP can change the output by inverter control according to an instruction from the control device 50.

[0048] As Figure 2 shown, the heat source well device 10 further includes a rectifying section 14, an injection thermometer 15, and an adjusting valve 16.

[0049] The rectifying section 14 is provided between the warm water well 11 and the cold water well 12 and the heat exchanger 40.

[0050] The rectifying section 14 is connected to the pipe 13 in the middle of the pipe 13 by a connection circuit including check valves CV1 to CV4. The rectifying section 14 rectifies the flow of water so that the water in the pipe 13 flows toward the heat exchanger 40. Therefore, the water in the pipe 13 flows toward the heat exchanger 40 regardless of whether it is drawn from either the hot water well 11 or the cold water well 12. Here, Figure 2 Each of the illustrated check valves CV1 to CV4 allows water to flow in the arrow direction and does not allow water to flow in the opposite direction of the arrow.

[0051] The water injection thermometer 15 is provided in the middle of the pipe 13 leading from the heat exchanger 40 to the rectifying section 14, that is, in the pipe 13 where the supply water flows from the heat exchanger 40 to the rectifying section 14.

[0052] The water injection thermometer 15 measures the temperature of the water flowing from the heat exchanger 40 to the rectifying section 14 and outputs the measurement result to the control device 50.

[0053] The regulating valve 16 is provided in the middle of the pipe 13 leading from the rectifying section 14 to the heat exchanger 40 and in the pipe 13 where the supply water flows from the rectifying section 14 to the heat exchanger 40.

[0054] The regulating valve 16 adjusts the flow rate of the water flowing from the rectifying section 14 to the heat exchanger 40 in response to an instruction from the control device 50, and controls the water injection amount into each well of the hot water well 11 and the cold water well 12.

[0055] (Configuration of the heat exchanger)

[0056] The heat exchanger 40 exchanges heat between the water in the pipe 13 and the media on the heat pump 30 side and the heat storage auxiliary equipment 20 side.

[0057] Specifically, the heat exchanger 40 exchanges heat between the groundwater drawn from the hot water well 11 as the water in the pipe 13 and flowing in the pipe 13 and the media on the heat pump 30 side and the heat storage auxiliary equipment 20 side. The groundwater after heat exchange flows into the pipe 13 from the heat exchanger 40 and is injected into the cold water well 12.

[0058] Conversely, the heat exchanger 40 exchanges heat between the groundwater drawn from the cold water well 12 as the water in the pipe 13 and flowing in the pipe 13 and the media on the heat pump 30 side and the heat storage auxiliary equipment 20 side. The groundwater after heat exchange flows into the pipe 13 from the heat exchanger 40 and is injected into the hot water well 11.

[0059] The heat exchanger 40 is provided in the middle of the pipe 13 extending on the ground.

[0060] When the water after passing through the heat exchanger 40 is hot water, hot water heat storage is performed in the hot water well 11.

[0061] When the water after passing through the heat exchanger 40 is cold water, cold water heat storage is performed in the cold water well 12.

[0062] Herein, "warm water" refers to water having a temperature higher than the initial underground temperature of the groundwater in the aquifer LY, and "cold water" refers to water having a temperature lower than the initial underground temperature of the groundwater in the aquifer LY. For example, the initial underground temperature of the groundwater in the aquifer LY is 18°C.

[0063] (Configuration of the heat pump)

[0064] The heat pump 30 includes a condenser, an evaporator, a compressor, etc., and is provided between the machine AA and the pipe 13 via the heat exchanger 40.

[0065] The heat pump 30 cools or heats the medium after heat exchange with the water in the pipe 13 through the heat exchanger 40. Thus, the heat pump 30 uses the thermal energy or cold energy obtained from the water in the pipe 13 for the machine AA, and on the other hand, accumulates the waste heat of thermal energy or cold energy discharged from the machine AA in the water in the pipe 13 via the heat exchanger 40.

[0066] In the present embodiment, a turbo heat pump is used as the heat pump 30.

[0067] The geothermal utilization system 1 further includes a plurality of switching valves 61 and a pump 62 to control the flow of the medium flowing between the heat pump 30 and the heat exchanger 40.

[0068] The plurality of switching valves 61 and the pump 62 are provided between the heat pump 30 and the heat exchanger 40.

[0069] The geothermal utilization system 1 further includes a pump 70 between the heat pump 30 and the machine AA to cause the medium to flow between the heat pump 30 and the machine AA.

[0070] (Configuration of the heat storage auxiliary device)

[0071] The heat storage auxiliary device 20 heats the cold water in the pipe 13 through the medium in the heat exchanger 40 to assist the heat storage in the warm water well 11.

[0072] In the present embodiment, the heat storage auxiliary device 20 includes a waste heat recovery mechanism 201, a cooling tower 202, and an air-cooled heat pump 203.

[0073] The waste heat recovery mechanism 201 recovers the waste heat generated in each process of the factory where the machine AA is provided and heats the medium of the heat storage auxiliary device 20.

[0074] The waste heat recovered by the waste heat recovery mechanism 201 is used for auxiliary heat storage in the warm water well 11.

[0075] The cooling tower 202 utilizes the heat of vaporization when water is vaporized by contacting the atmosphere, and has the normal function of cooling the medium of the heat storage auxiliary device 20. In this embodiment, it also has the function of a heating tower. That is, the cooling tower 202 can cool the medium of the heat storage auxiliary device 20 during, for example, winter when the temperature of the atmosphere is low, but can heat the medium of the heat storage auxiliary device 20 during, for example, summer when the temperature of the atmosphere is high.

[0076] Therefore, the cooling tower 202 can be used not only as a device for auxiliary cold storage to the cold water well 12, but also as a device for auxiliary heat storage to the warm water well 11. For example, the cooling tower 202 can also be configured to heat the medium of the heat storage auxiliary device 20 when the external air temperature is higher than the set water injection temperature.

[0077] The air-cooled heat pump 203 includes a condenser, an evaporator, a compressor, etc., and heats the medium of the heat storage auxiliary device 20.

[0078] The air-cooled heat pump 203 can perform heating operation throughout the year.

[0079] The heat after heating the medium by the air-cooled heat pump 203 is used for auxiliary heat storage to the warm water well 11. On the other hand, the heat after heating the medium by the air-cooled heat pump 203 is also used for heating in the machine AA.

[0080] The heat storage auxiliary device 20 further includes a plurality of switching valves 204, a pump 205, a heat exchanger 206, and an outlet thermometer 207.

[0081] The primary side of the heat exchanger 206 is connected to the heat exchanger 40 via the pump 62 such that the medium flows between the primary side and the heat exchanger 40.

[0082] In response to the instruction of the control device 50, the heat storage auxiliary device 20 switches the plurality of switching valves 204. Thus, it can switch between a circuit for allowing the medium to flow between the heat exchanger 206 and the cooling tower 202 and a circuit for allowing the medium to flow between the heat exchanger 206 and the waste heat recovery mechanism 201.

[0083] Thereby, in the heat storage auxiliary device 20, the secondary side of the heat exchanger 206 can be connected to the cooling tower 202 or the waste heat recovery mechanism 201 such that the medium flows between the secondary side of the heat exchanger 206 and the cooling tower 202 or the waste heat recovery mechanism 201.

[0084] Therefore, the heat storage auxiliary device 20 can switch between the action of storing the heat obtained from the cooling tower 202 in the water in the pipe 13 via the heat exchanger 40 and the action of storing the heat obtained from the waste heat recovery mechanism 201 in the water in the pipe 13.

[0085] The outlet thermometer 207 is provided at the outlet of the medium on the primary side of the heat exchanger 206 that travels to the heat exchanger 40.

[0086] The heat storage auxiliary device 20 further includes a plurality of switching valves 208.

[0087] The air-cooled heat pump 203 is connected to the heat exchanger 40 via a plurality of switching valves 208 and a pump 62.

[0088] In response to an instruction from the control device 50, the heat storage auxiliary device 20 can switch the plurality of switching valves 208. Thus, the heat storage auxiliary device 20 can switch between an operation of connecting to the heat exchanger 40 via the pump 62 in such a manner that the medium flows between the air-cooled heat pump 203 and the heat exchanger 40 and an operation of disconnecting from the heat exchanger 40 in such a manner that the medium does not flow between the air-cooled heat pump 203 and the heat exchanger 40.

[0089] The geothermal utilization system 1 further includes a plurality of switching valves 80 between the air-cooled heat pump 203 and the machine AA. Thus, the geothermal utilization system 1 can switch between an operation of connecting the air-cooled heat pump 203 to the machine AA in such a manner that the medium flows between the air-cooled heat pump 203 and the machine AA and an operation of disconnecting the connection between the air-cooled heat pump 203 and the machine AA in such a manner that the medium does not flow between the air-cooled heat pump 203 and the machine AA.

[0090] (Configuration of the control device)

[0091] As Figure 3 shown, the control device 50 functionally includes a first mode control unit 511, a second mode control unit 512, a third mode control unit 513, an outlet temperature control unit 514, and a water injection temperature control unit 515.

[0092] The control device 50 includes a CPU (Central Processing Unit), a memory 52, a communication interface 53, and a recording medium 54 as a hardware configuration.

[0093] The CPU 51 is a processor that functions by operating according to a pre-prepared program. The functions of the CPU 51 will be described later.

[0094] The memory 52 has a storage area required for the operation of the CPU 51.

[0095] The communication interface 53 is a connection interface for communicably connecting to other devices via a communication line or the like, and is configured to be able to send instructions to other devices or receive responses from other devices.

[0096] The recording medium 54 is a local recording medium provided in the housing of the control device 50 and is a large-capacity storage device such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive).

[0097] Next, the functions of the CPU 51 of the control device 50 will be described.

[0098] The CPU 51 functions as the first mode control unit 511, the second mode control unit 512, the third mode control unit 513, the outlet temperature control unit 514, and the water injection temperature control unit 515 as described above by operating according to a pre-prepared program.

[0099] The first mode control unit 511 controls the geothermal utilization system 1 in the first mode.

[0100] The first mode is a mode mainly implemented during summer, in which the cold energy stored in the cold water well 12 is supplied to the machine AA, and the thermal energy obtained from the machine AA is stored in the warm water well 11.

[0101] The second mode control unit 512 controls the geothermal utilization system 1 in the second mode instead of the first mode.

[0102] The second mode is a mode in which the cold energy stored in the cold water well 12 is supplied to the heat storage auxiliary device 20, and the thermal energy obtained from the heat storage auxiliary device 20 is stored in the warm water well 11.

[0103] For example, the second mode control unit 512 controls the geothermal utilization system 1 in the second mode during summer.

[0104] The third mode control unit 513 controls the geothermal utilization system 1 in the third mode.

[0105] The third mode is a mode mainly implemented during winter, in which the thermal energy stored in the warm water well 11 is supplied to the machine AA, and the cold energy obtained from the machine AA is stored in the cold water well 12.

[0106] The outlet temperature control unit 514 controls the geothermal utilization system 1 so that the temperature of the medium measured by the outlet thermometer 207 as the temperature of the medium at the outlet of the heat storage auxiliary device 20 is constant.

[0107] The water injection temperature control unit 515 controls the geothermal utilization system 1 so that the water injection temperature measured by the water injection thermometer 15 as the water injection temperature into the warm water well 11 or the cold water well 12 is constant.

[0108] (Operation of the control device)

[0109] The operation of the control device 50 of the present embodiment will be described.

[0110] The operation of the control device 50 corresponds to an embodiment of the control method.

[0111] The control device 50 executes Figure 4 each of the steps shown.

[0112] First, the first mode control unit 511 controls the geothermal utilization system 1 in the first mode (ST01: first mode control step).

[0113] The first mode is mainly executed during summer.

[0114] The first mode is the operation when machine AA uses refrigeration.

[0115] In the first mode, the first mode control unit 511 sends an instruction to the pump PP of the cold water well 12 to make it work, and sends an instruction to the injection valve VA of the warm water well 11 to open it. Moreover, in the first mode, the first mode control unit 511 switches the switching valves 61, 204, and 208 so that the medium flows to machine AA and does not flow to the heat storage auxiliary device 20.

[0116] Thereby, as Figure 5 shown, the geothermal utilization system 1 pumps the cold water stored in the cold water well 12 into the pipe 13 and supplies it to the heat exchanger 40, thereby cooling the medium on the heat pump 30 side. The cooled medium functions as a refrigerant for refrigeration in machine AA.

[0117] On the other hand, the cold water after being supplied to the heat exchanger 40 becomes warm water by cooling the medium on the heat pump 30 side, passes through the pipe 13 toward the warm water well 11 and is discharged, and injects water into the warm water well 11. Thereby, warm water is stored in the warm water well 11.

[0118] Moreover, the injection temperature control unit 515 performs inverter control of the pump PP of the cold water well 12, control of the adjustment valve 16, etc. so that the injection temperature into the warm water well 11 is constant.

[0119] Following the execution of ST01, the second mode control unit 512 controls the geothermal utilization system 1 in the second mode instead of the first mode (ST02: second mode control step).

[0120] For example, the second mode is executed during summer. At this time, the second mode control unit 512 detects that it is during summer by obtaining the date, month, year, average temperature of the external air, operator input, etc., and controls the geothermal utilization system 1 in the second mode during summer.

[0121] The second mode is a mode used when it is predicted that there will be a shortage of warm water during winter, such as in cold regions. For example, it is an operation for preparing for winter by heating the cold water pumped out from the cold water well 12 by the heat storage auxiliary device 20 during summer, and thus storing warm water in the warm water well 11 differently from the first mode.

[0122] In the second mode, the second mode control unit 512 sends an instruction to the pump PP of the cold water well 12 to operate, and sends an instruction to the water injection valve VA of the warm water well 11 to open. Moreover, in the second mode, the second mode control unit 512 sends instructions to the switching valves 61, 204, 208 so that the medium flows to the heat storage auxiliary device 20 and does not flow to the machine AA.

[0123] Thereby, the geothermal utilization system 1 pumps the cold water stored in the cold water well 12 into the pipe 13 and supplies it to the heat exchanger 40. On the other hand, as Figures 6 to 8 shown, the medium heated by the heat storage auxiliary device 20 is supplied to the heat storage auxiliary device 20 side of the heat exchanger 40, and the cold water supplied from the cold water well 12 to the heat exchanger 40 is heated to become warm water. The heated warm water passes through the pipe 13 and is discharged toward the warm water well 11, and the warm water well 11 is filled with water. Thereby, in addition to the warm water stored in the first mode, warm water is also stored in the warm water well 11.

[0124] In the implementation of ST02, the outlet temperature control unit 514 controls the geothermal utilization system 1 so that the temperature of the medium at the outlet of the heat storage auxiliary device 20 is constant, and the water injection temperature control unit 515 controls the geothermal utilization system 1 so that the water injection temperature into the warm water well 11 is constant.

[0125] In the implementation of ST02, the control device 50 automatically switches the operation mode of the geothermal utilization system 1 to any one of the following waste heat utilization mode, cooling tower utilization mode, and air-cooled heat pump utilization mode in consideration of the cooling and heating load in the machine AA and the external air temperature, etc.

[0126] <Waste heat utilization mode>

[0127] In the case where there is waste heat generated in each process in the factory where the machine AA is installed, as the waste heat utilization mode, the control device 50 uses the waste heat and operates the geothermal utilization system 1 in a mode of storing heat in the warm water well 11.

[0128] In the waste heat utilization mode, the water injection temperature control unit 515 performs inverter control of the pump PP of the cold water well 12 so that the water injection temperature into the warm water well 11 is constant, and at the same time performs bypass control so that the heat obtained by the waste heat recovery mechanism 201 can be stored in the water in the pipe 13. Specifically, as Figure 6As shown in the figure, the water injection temperature control unit 515 performs bypass control to send an instruction to the switching valve 204 in such a way that the medium flows between the waste heat recovery mechanism 201 and the heat exchanger 206, and at the same time performs inverter control of the pump 205 and control of the regulating valve 16 in such a way that the temperature of the medium at the outlet of the heat storage auxiliary device 20 is constant.

[0129] <Cooling tower utilization mode>

[0130] In the case where waste heat generated in each process in a factory where machine AA is not installed or the waste heat is insufficient, as the cooling tower utilization mode, the control device 50 operates the cooling tower 202 to make the geothermal utilization system 1 operate in a mode of storing heat in the warm water well 11. The operating condition of this mode is when the external air wet-bulb temperature is higher than the set water injection temperature.

[0131] In the cooling tower utilization mode, the water injection temperature control unit 515 performs inverter control of the pump PP in the cold water well 12 in such a way that the water injection temperature into the warm water well 11 is constant, and at the same time performs bypass control in such a way that the heat obtained from the cooling tower 202 can be stored in the water in the pipe 13.

[0132] Specifically, as Figure 7 shown, the water injection temperature control unit 515 performs bypass control to send an instruction to the switching valve 204 in such a way that the medium flows between the cooling tower 202 and the heat exchanger 206, and at the same time performs inverter control of the pump 205 and control of the regulating valve 16 in such a way that the temperature of the medium at the outlet of the heat storage auxiliary device 20 is constant.

[0133] <Air-cooled heat pump utilization mode>

[0134] When there is insufficient warm water for heating during winter by only using the waste heat utilization mode and the cooling tower utilization mode, as the air-cooled heat pump utilization mode, the control device 50 operates the air-cooled heat pump 203 to make the geothermal utilization system 1 operate in a mode of storing heat in the warm water well 11. At this time, as Figure 8 shown, the water injection temperature control unit 515 sends an instruction to the switching valve 208 in such a way that the medium flows between the air-cooled heat pump 203 and the heat exchanger 40.

[0135] The feature of this mode is that the required warm water heat storage can be carried out at any time, and heating operation is performed during summer. Therefore, the COP (Coefficient Of Performance) of the air-cooled heat pump 203 is high, and the COP of the entire system can be improved.

[0136] After the implementation of ST02 is completed, ST01 is implemented again. After that, for example, during the entire summer period, ST01 and ST02 are repeatedly carried out.

[0137] Subsequent to the implementation of ST01 and ST02, the third mode control unit 513 controls the geothermal utilization system 1 in the third mode (third mode control step: ST03).

[0138] The third mode is mainly implemented during winter.

[0139] The third mode is the operation of machine AA during heating.

[0140] In the third mode, the third mode control unit 513 sends an instruction to the pump PP of the warm water well 11 to make it operate, and sends an instruction to the water injection valve VA of the cold water well 12 to open it. Moreover, in the third mode, the third mode control unit 513 sends instructions to the switching valves 61, 204, and 208 so that the medium flows to machine AA and does not flow to the heat storage auxiliary device 20.

[0141] Thus, as Figure 9 shown, the geothermal utilization system 1 pumps the warm water stored in the warm water well 11 into the pipe 13 and supplies it to the heat exchanger 40, thereby heating the medium on the heat pump 30 side. The heated medium functions as a heat medium for heating in machine AA. On the other hand, the warm water supplied to the heat exchanger 40 becomes cold water by heating the medium on the heat pump 30 side, passes through the pipe 13 toward the cold water well 12 and is discharged, and water is injected into the cold water well 12. Thus, cold water is stored in the cold water well 12.

[0142] In ST03, the water injection temperature control unit 515 performs Inverter control of the pump PP of the warm water well 11, control of the adjustment valve 16, etc. so that the water injection temperature into the cold water well 12 is constant.

[0143] In the third mode, when the warm water stored in the warm water well 11 is insufficient, the geothermal utilization system 1 connects the air-cooled heat pump 203 to machine AA by switching multiple switching valves 80 so that the medium flows between machine AA and the air-cooled heat pump 203, and utilizes the air-cooled heat pump 203 during the heating of machine AA.

[0144] (Function and effect)

[0145] According to this embodiment, in addition to being able to store the thermal energy obtained from machine AA in the warm water well 11, the control device 50 can also store the thermal energy obtained from the heat storage auxiliary device 20 in the warm water well 11.

[0146] Therefore, the stored thermal energy is not easily insufficient.

[0147] In addition, according to this embodiment, the waste heat recovery mechanism 201 recovers the waste heat of the factory, so the waste heat can be effectively utilized.

[0148] Therefore, the environmental burden is reduced.

[0149] In addition, according to the present embodiment, the control device 50 can control the temperature of the medium at the outlet of the heat storage auxiliary device 20 to be constant.

[0150] Therefore, the heat storage auxiliary device 20 can stably assist in heat storage in the warm water well 11.

[0151] In addition, according to the present embodiment, the control device 50 can control the injection water temperature into the warm water well 11 to be constant, so that the temperature of the warm water well 11 can be maintained constant.

[0152] In addition, according to the present embodiment, the control device 50 is controlled in the second mode during summer, whereby the thermal energy obtained from the heat storage auxiliary device 20 can be stored in the warm water well 11 during summer.

[0153] Therefore, the geothermal utilization system 1 can easily store thermal energy even in cold regions and can continuously utilize geothermal energy.

[0154] Generally, in a geothermal utilization system using an aquifer, in long-term operation, it is necessary to maintain the annual heat balance and the pumping / return water volume balance.

[0155] If geothermal energy is simply utilized without considering the difference in air-conditioning loads (heat) between summer and winter, it will lead to an imbalance in heat or volume between cold water and warm water.

[0156] Therefore, due to the continuous expansion of the heat storage blocks for cooling waste heat or heating waste heat, efficient geothermal utilization cannot be carried out, and it may also have an adverse impact on the underground environment.

[0157] For example, in the case of western Japan where the cooling load during summer is larger than the heating load during winter, in addition to the normal operation during winter, heat and mass balance can be maintained by cold storage using a chiller and a cooling tower.

[0158] However, in the case of eastern Japan where the heating load during winter is larger than the cooling load during summer, there is too much cold energy storage, so it is necessary to store warm water heat during summer.

[0159] Thus, if a scheme for storing warm water heat during summer is not studied, it may be difficult to introduce a geothermal utilization system in cold regions.

[0160] As a comparative example, there is an example of using a geothermal utilization system in the Netherlands in accordance with the cooling load, but in cold regions such as Hokkaido, the geothermal utilization system cannot be utilized in regions with a small cooling load during summer.

[0161] Therefore, the control device 50 according to the present embodiment can store the thermal energy obtained from the heat storage auxiliary device 20 in the warm water well 11 during summer, so it is easy to introduce the geothermal utilization system 1 into cold regions.

[0162] In addition, according to the present embodiment, heat exchange is performed between the water in the pipe 13 and the media on the machine AA side and the heat storage auxiliary device 20 side. Therefore, it is easy to perform heat reception between the heat source well device 10 and the machine AA, and between the heat source well device 10 and the heat storage auxiliary device 20.

[0163] In addition, according to the present embodiment, the heat storage auxiliary device 20 includes a cooling tower 202. Therefore, natural energy can be effectively utilized, energy conservation can be achieved, and carbon neutrality can be contributed to.

[0164] In addition, according to the present embodiment, the heat storage auxiliary device 20 includes a waste heat recovery mechanism 201, a cooling tower 202, and an air-cooled heat pump 203. Therefore, a system can be constructed according to the user's usage.

[0165] <Modification Example>

[0166] In the above embodiment, the second mode control unit 512 controls the geothermal utilization system 1 in the second mode during summer, but any control method can be used as long as the thermal energy obtained from the heat storage auxiliary device 20 can be stored in the warm water well 11.

[0167] As a first modification example, the second mode control unit 512 can control the geothermal utilization system 1 in the second mode not only during summer but also during spring, autumn, or winter other than summer.

[0168] As a second modification example, the second mode control unit 512 can also control the geothermal utilization system 1 in the second mode regardless of the season.

[0169] As a third modification example, the second mode control unit 512 can also perform control in the second mode when the external air temperature is higher than the set injection temperature.

[0170] In the above embodiment, the heat storage auxiliary device 20 includes a waste heat recovery mechanism 201, a cooling tower 202, and an air-cooled heat pump 203, but any configuration can be used as long as it can assist in heat storage in the warm water well 11.

[0171] As a modification example, the heat storage auxiliary device 20 can also include a waste heat recovery mechanism 201 and a cooling tower 202 without including an air-cooled heat pump 203.

[0172] As another modification example, the heat storage auxiliary device 20 can also include at least one of a waste heat recovery mechanism 201, a cooling tower 202, and an air-cooled heat pump 203.

[0173] In the above-described embodiment, in the cooling tower utilization mode of ST02, the heat storage auxiliary device 20 only utilizes the cooling tower 202 among the waste heat recovery mechanism 201, the cooling tower 202, and the air-cooled heat pump 203. However, as long as it can assist in heat storage in the hot water well 11, it can be utilized in any way. As a modification example, in the cooling tower utilization mode, the heat storage auxiliary device 20 may also utilize the waste heat recovery mechanism 201 and the cooling tower 202 simultaneously. For example, the water injection temperature control unit 515 may also be as Figure 10 shown to perform bypass control in such a manner that the medium flows between the cooling tower 202 and the heat exchanger 206, and between the waste heat recovery mechanism 201 and the heat exchanger 206. Thus, the heat storage auxiliary device 20 can utilize the waste heat recovery mechanism 201 and the cooling tower 202 in parallel and simultaneously.

[0174] In the above-described embodiment, in the air-cooled heat pump utilization mode of ST02, only the air-cooled heat pump 203 among the waste heat recovery mechanism 201, the cooling tower 202, and the air-cooled heat pump 203 is utilized. However, as long as it can assist in heat storage in the hot water well 11, it can be utilized in any way. As a modification example, in the air-cooled heat pump utilization mode, the heat storage auxiliary device 20 may also utilize the waste heat recovery mechanism 201, the cooling tower 202, and the air-cooled heat pump 203 simultaneously. For example, the control device 50 may also be as Figure 11 shown to perform bypass control in such a manner that the medium flows between the air-cooled heat pump 203 and the heat exchanger 40, between the cooling tower 202 and the heat exchanger 206, and between the waste heat recovery mechanism 201 and the heat exchanger 206. Thus, the heat storage auxiliary device 20 can utilize the waste heat recovery mechanism 201, the cooling tower 202, and the air-cooled heat pump 203 in parallel and simultaneously.

[0175] It should be noted that in the above-described embodiments, programs for implementing various functions of the control device 50 are recorded on a computer-readable recording medium, and the programs recorded on this recording medium are read into a computer system and executed, thereby performing various processes. Here, the processes of the CPU 51 of the computer system are stored in the form of programs on a computer-readable recording medium, and the computer reads and executes this program, thereby performing the above-described various processes. In addition, the computer-readable recording medium refers to a magnetic disk, an optical disk, a CD-ROM (Compact Disc Read-Only Memory), a DVD-ROM (Digital Video Disc-Read Only Memory), a semiconductor memory, etc. In addition, this computer program may also be transmitted to a computer via a communication line or the like, and the computer that receives this transmission executes this program.

[0176] <Other Embodiments>

[0177] As described above, the embodiments of the present disclosure have been described, but these embodiments are presented as examples and are not intended to limit the scope of the present disclosure. These embodiments can be implemented in various other ways, and various omissions, substitutions, and changes can be made without departing from the gist of the present disclosure. These embodiments and their modifications are included in the scope and gist of the present disclosure, and similarly, they are also included in the scope of the present disclosure and its equivalent scope.

[0178] <Supplementary Note>

[0179] For example, the control device 50, the geothermal utilization system 1, the control method, and the program described in the above embodiments are understood as follows.

[0180] (1) The control device 50 of the first aspect includes: a first mode control unit 511 that controls the geothermal utilization system 1 in a first mode. The geothermal utilization system 1 includes a heat source well device 10 including a warm water well 11 and a cold water well 12, and a heat storage auxiliary device 20 including a waste heat recovery mechanism 201, a cooling tower 202, or an air-cooled heat pump 203. In the first mode, the cold energy stored in the cold water well 12 is supplied to the machine AA, and the thermal energy obtained from the machine AA is stored in the warm water well 11; and a second mode control unit 512 that controls the geothermal utilization system 1 in a second mode instead of the first mode. In the second mode, the cold energy stored in the cold water well 12 is supplied to the heat storage auxiliary device 20, and the thermal energy obtained from the heat storage auxiliary device 20 is stored in the warm water well 11.

[0181] According to this aspect, the control device 50 can store not only the thermal energy obtained from the machine AA in the warm water well 11 but also the thermal energy obtained from the heat storage auxiliary device 20 in the warm water well 11.

[0182] Therefore, the stored thermal energy is less likely to be insufficient.

[0183] (2) The control device 50 of the second aspect is the control device 50 of (1), wherein the waste heat recovery mechanism 201 recovers the waste heat of the factory.

[0184] According to this aspect, the waste heat recovery mechanism 201 can effectively utilize the waste heat.

[0185] Therefore, the environmental burden is reduced.

[0186] (3) The control device 50 of the third aspect is the control device 50 of (1) or (2), wherein the control device 50 further includes an outlet temperature control unit 514 that controls the geothermal utilization system 1 so that the temperature of the medium at the outlet of the heat storage auxiliary device 20 is constant.

[0187] According to this solution, the control device 50 can control the temperature of the medium at the outlet of the heat storage auxiliary device 20 to be constant.

[0188] Therefore, the heat storage auxiliary device 20 can stably assist in heat storage in the warm water well 11.

[0189] (4) The control device 50 of the fourth solution is any one of the control devices 50 in (1) to (3), wherein the control device 50 further includes a water injection temperature control unit 515, and the water injection temperature control unit 515 controls the geothermal utilization system 1 in such a way that the water injection temperature into the warm water well 11 is constant.

[0190] According to this solution, the control device 50 can control the water injection temperature into the warm water well 11 to be constant, so that the temperature of the warm water well 11 can be kept constant.

[0191] (5) The control device 50 of the fifth solution is any one of the control devices 50 in (1) to (4), wherein the second mode control unit 512 controls the geothermal utilization system in the second mode during summer.

[0192] According to this solution, the control device 50 can store the heat energy obtained from the heat storage auxiliary device 20 in the warm water well 11 during summer.

[0193] Therefore, the geothermal utilization system 1 can easily store heat energy even in cold regions and can continuously utilize geothermal energy.

[0194] (6) The control device 50 of the sixth solution is any one of the control devices 50 in (1) to (5), wherein the heat source well device 10 further includes: a pipe 13 connecting the warm water well 11 and the cold water well 12; and a heat exchanger 40 that exchanges heat between the water in the pipe 13 and the media on the machine AA side and the heat storage auxiliary device 20 side.

[0195] According to this solution, heat exchange is performed between the water in the pipe 13 and the media on the machine AA side and the heat storage auxiliary device 20 side. Therefore, it is easy to perform heat reception between the heat source well device 10 and the machine AA, and between the heat source well device 10 and the heat storage auxiliary device 20.

[0196] (7) The geothermal utilization system 1 of the seventh solution includes: any one of the control devices 50 in (1) to (6); the heat source well device 10; and the heat storage auxiliary device 20.

[0197] According to this solution, the geothermal utilization system 1 can not only store the heat energy obtained from the machine AA in the warm water well 11, but also store the heat energy obtained from the heat storage auxiliary device 20 in the warm water well 11.

[0198] Therefore, the stored heat energy is not likely to be insufficient.

[0199] (8) Control method of the eighth solution, wherein the geothermal utilization system 1 is controlled in a first mode. The geothermal utilization system 1 includes a heat source well device 10 including a warm water well 11 and a cold water well 12, and a heat storage auxiliary device 20 including a waste heat recovery mechanism 201, a cooling tower 202, or an air-cooled heat pump 203. In the first mode, the cold energy stored in the cold water well 12 is supplied to the machine AA, and the heat energy obtained from the machine AA is stored in the warm water well 11. The geothermal utilization system 1 is controlled in a second mode instead of the first mode. In the second mode, the cold energy stored in the cold water well 12 is supplied to the heat storage auxiliary device 20, and the heat energy obtained from the heat storage auxiliary device 20 is stored in the warm water well 11.

[0200] According to this solution, the control method can not only store the heat energy obtained from the machine AA in the warm water well 11, but also store the heat energy obtained from the heat storage auxiliary device 20 in the warm water well 11.

[0201] Therefore, the stored heat energy is not easily insufficient.

[0202] (9) The program of the ninth solution causes a computer to perform the following control: controlling the geothermal utilization system 1 in a first mode. The geothermal utilization system 1 includes a heat source well device 10 including a warm water well 11 and a cold water well 12, and a heat storage auxiliary device 20 including a waste heat recovery mechanism 201, a cooling tower 202, or an air-cooled heat pump 203. In the first mode, the cold energy stored in the cold water well 12 is supplied to the machine AA, and the heat energy obtained from the machine AA is stored in the warm water well 11. The geothermal utilization system 1 is controlled in a second mode instead of the first mode. In the second mode, the cold energy stored in the cold water well 12 is supplied to the heat storage auxiliary device 20, and the heat energy obtained from the heat storage auxiliary device 20 is stored in the warm water well 11.

[0203] According to this solution, the program can not only store the heat energy obtained from the machine AA in the warm water well 11, but also store the heat energy obtained from the heat storage auxiliary device 20 in the warm water well 11.

[0204] Therefore, the stored heat energy is not easily insufficient.

[0205] Industrial availability

[0206] According to one of the above solutions, the stored heat energy is not easily insufficient.

[0207] Explanation of reference numerals

[0208] 1: Geothermal utilization system;

[0209] 11: Warm water well;

[0210] 12: Cold water well;

[0211] 13: Pipe;

[0212] 14: Rectifying section;

[0213] 15: Injection thermometer;

[0214] 16: Control valve;

[0215] 20: Heat storage auxiliary device;

[0216] 30: Heat pump;

[0217] 40: Heat exchanger;

[0218] 50: Control device;

[0219] 51: CPU;

[0220] 52: Memory;

[0221] 53: Communication interface;

[0222] 54: Recording medium;

[0223] 61: Switching valve;

[0224] 62: Pump;

[0225] 70: Pump;

[0226] 80: Switching valve;

[0227] 131: First end;

[0228] 132: Second end;

[0229] 201: Waste heat recovery mechanism;

[0230] 202: Cooling tower;

[0231] 203: Air-cooled heat pump;

[0232] 204: Switching valve;

[0233] 205: Pump;

[0234] 206: Heat exchanger;

[0235] 207: Outlet thermometer;

[0236] 208: Switching valve;

[0237] 511: First mode control section;

[0238] 512: Second mode control section;

[0239] 513: Third mode control unit;

[0240] 514: Outlet temperature control unit;

[0241] 515: Water injection temperature control unit;

[0242] AA: Machine;

[0243] CV1: Check valve;

[0244] CV2: Check valve;

[0245] CV3: Check valve;

[0246] CV4: Check valve;

[0247] LY: Aquifer;

[0248] PP: Pump;

[0249] VA: Water injection valve;

[0250] VB: Check valve.

Claims

1. A control device, the control device comprising: A first mode control unit that controls a geothermal utilization system in a first mode. The geothermal utilization system includes a heat source well device including a warm water well and a cold water well, and a heat storage auxiliary device including a waste heat recovery mechanism, a cooling tower, or an air-cooled heat pump. In the first mode, the cold energy stored in the cold water well is supplied to a machine, and the heat energy obtained from the machine is stored in the warm water well; and A second mode control unit that controls the geothermal utilization system in a second mode instead of the first mode. In the second mode, the cold energy stored in the cold water well is supplied to the heat storage auxiliary device, and the heat energy obtained from the heat storage auxiliary device is stored in the warm water well.

2. The control device according to claim 1, wherein The waste heat recovery mechanism recovers waste heat from a factory.

3. The control device according to claim 1 or 2, wherein The control device further includes an outlet temperature control unit that controls the geothermal utilization system in such a manner that the temperature of the medium at the outlet of the heat storage auxiliary device is constant.

4. The control device according to claim 1 or 2, wherein The control device further includes a water injection temperature control unit that controls the geothermal utilization system in such a manner that the water injection temperature into the warm water well is constant.

5. The control device according to claim 1 or 2, wherein The second mode control unit controls the geothermal utilization system in the second mode during summer.

6. The control device according to claim 1 or 2, wherein The heat source well device further includes: Pipes that connect the warm water well and the cold water well; and A heat exchanger that performs heat exchange between the water in the pipes and the media on the machine side and the heat storage auxiliary device side.

7. A geothermal utilization system, the geothermal utilization system comprising: The control device according to claim 1 or 2; The heat source well device; and The heat storage auxiliary device.

8. A control method, wherein A geothermal utilization system is controlled in a first mode. The geothermal utilization system includes a heat source well device including a warm water well and a cold water well, and a heat storage auxiliary device including a waste heat recovery mechanism, a cooling tower, or an air-cooled heat pump. In the first mode, the cold energy stored in the cold water well is supplied to a machine, and the heat energy obtained from the machine is stored in the warm water well, The geothermal utilization system is controlled in a second mode instead of the first mode. In the second mode, the cold energy stored in the cold water well is supplied to the heat storage auxiliary device, and the heat energy obtained from the heat storage auxiliary device is stored in the warm water well.

9. A program that causes a computer to execute the following control: A geothermal utilization system is controlled in a first mode. The geothermal utilization system includes a heat source well device including a warm water well and a cold water well, and a heat storage auxiliary device including a waste heat recovery mechanism, a cooling tower, or an air-cooled heat pump. In the first mode, the cold energy stored in the cold water well is supplied to a machine, and the heat energy obtained from the machine is stored in the warm water well, Control the geothermal utilization system by replacing the first mode with a second mode. In the second mode, supply the cold energy stored in the cold water well to the heat storage auxiliary device, and store the heat energy obtained from the heat storage auxiliary device in the warm water well.

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