JP2021004700A - Underground heat utilization system, control device, control method, and program - Google Patents

Abstract

To provide an underground heat utilization system, a control device, a control method, and a program that can restrain fluctuations in a flow rate of water supplied to a heat exchanger.SOLUTION: An underground heat utilization system 10 comprises: a cushion tank 20 connected to a hot water well WLH and a cold water well WLC; a heat exchanger 30 connected to the cushion tank 20, and exchanging heat with a heat medium of a heat source machine R; a hot water pump 40; a cold water pump 50; a load pipe 60L; a load flowmeter 70L; and a control device 80. The control device 80 comprises a load flow rate acquisition unit for acquiring a load flow rate FL, a first determination unit for determining a first command C1 on the basis of the load flow rate FL, and a first command unit for sending the first command C1 to the hot water pump 40 or the cold water pump 50.SELECTED DRAWING: Figure 1

Description

The present invention relates to geothermal heat utilization systems, control devices, control methods, and programs.

In recent years, a geothermal heat utilization system has been proposed in which groundwater in an aquifer is pumped up from a well and used as a heat source or a cold heat source.

As a technique related to this, for example, Patent Document 1 discloses a geothermal heat utilization system in which the heat of water taken from an aquifer is used via a heat exchanger to recirculate the aquifer. ing.

Japanese Unexamined Patent Publication No. 09-280689

However, in the case of a geothermal heat utilization system as in Patent Document 1, the flow rate of water supplied to the heat exchanger may fluctuate depending on the water intake status, the water distribution status to the heat exchanger, and the like.

The present invention is a geothermal heat utilization system, a control device, a control method, and a program capable of suppressing fluctuations in the flow rate of water supplied to a heat exchanger.

The first aspect is based on a cushion tank connected to a hot water well and a cold water well, a heat exchanger connected to the cushion tank and exchanging heat with a heat medium of a heat source machine, and a first command. A hot water pump capable of pumping water from the hot water well, a cold water pump capable of pumping water from the cold water well based on the first command, and a load pipe connecting the cushion tank and the heat exchanger. A load flow meter for measuring the load flow rate, which is the flow rate of water flowing through the load piping, and a control device are provided, and the control device obtains the measured load flow rate, and the load flow rate acquisition unit and the load flow rate. A first specific unit for specifying the first command and a first command unit for sending the first command to the hot water pump or the cold water pump are provided based on the above.

According to this aspect, the geothermal heat utilization system includes a cushion tank and controls a hot water pump or a cold water pump based on the load flow rate.
Therefore, in the geothermal heat utilization system, in addition to being able to absorb fluctuations in the load flow rate in the cushion tank, fluctuations in the water level in the cushion tank can be suppressed.
Therefore, the geothermal heat utilization system can suppress fluctuations in the flow rate of water supplied to the heat exchanger.

The second aspect further includes a hot water pipe connecting the cushion tank and the hot water well, and a hot water flow meter for measuring the hot water flow rate, which is the flow rate of hot water flowing through the hot water pipe, and further comprises the load flow rate. The acquisition unit acquires the flow rate of hot water flowing from the cushion tank to the load pipe or the flow rate of cold water flowing into the cushion tank from the load pipe as the load flow rate, and the first specific unit obtains the load flow rate. This is the underground heat utilization system of the first aspect in which the first command is specified based on the flow rate and the hot water flow rate, and the first command unit sends the first command to the hot water pump.

According to this aspect, the hot water pump is controlled based on the load flow rate and the hot water flow rate.
Therefore, the geothermal heat utilization system can suppress fluctuations in the amount of hot water in the cushion tank.

In the third aspect, the hot water pipe is connected to a plurality of the hot water wells, and the first specific portion balances the load flow rate with the total flow rate of the hot water flowing through the hot water pipe. It is a geothermal heat utilization system of the second aspect that specifies the first command.

According to this aspect, the amount of hot water corresponding to the hot water flowing out of the cushion tank can be supplied from a plurality of hot water wells.
Therefore, the geothermal heat utilization system can compensate the hot water flowing out of the cushion tank with the other hot water well even if the amount of hot water supplied from one of the hot water wells is changed or limited. ..
Therefore, the geothermal heat utilization system can suppress fluctuations in the amount of hot water in the cushion tank.

A fourth aspect further comprises a chilled water pipe connecting the cushion tank and the chilled water well, and a chilled water flow meter for measuring the chilled water flow rate, which is the flow rate of chilled water flowing through the chilled water pipe, and further comprises the load flow rate. The acquisition unit acquires the flow rate of cold water flowing out of the cushion tank or the flow rate of hot water flowing into the cushion tank as the load flow rate, and the first specific unit is based on the load flow rate and the cold water flow rate. This is the underground heat utilization system of the first aspect in which the first command is specified and the first command unit sends the first command to the cold water pump.

According to this aspect, the chilled water pump is controlled based on the load flow rate and the chilled water flow rate.
Therefore, the geothermal heat utilization system can suppress fluctuations in the amount of cold water in the cushion tank.

In a fifth aspect, the chilled water pipe is connected to a plurality of the chilled water wells, and the first specific portion balances the load flow rate with the total flow rate of the chilled water flowing through the chilled water pipe. , The geothermal heat utilization system of the fourth aspect for specifying the first command.

According to this aspect, the amount of cold water corresponding to the cold water flowing out of the cushion tank can be supplied from a plurality of cold water wells.
Therefore, the geothermal heat utilization system can compensate the chilled water flowing out of the cushion tank with the other chilled water well even if the amount of chilled water supplied from one of the chilled water wells is changed or limited. ..
Therefore, the geothermal heat utilization system can suppress fluctuations in the amount of cold water in the cushion tank.

In a sixth aspect, the cushion tank comprises a thermometer that measures the temperature of water at a predetermined water level in the cushion tank, and the control device specifies a second command based on the measured temperature. The geothermal heat utilization system according to any one of the first to fifth aspects, further comprising a second specific unit and a second command unit that sends the second command to the hot water pump or the cold water pump.

According to this aspect, the hot water pump or the cold water pump is controlled based on the temperature of water at a predetermined water level in the cushion tank.
Therefore, the geothermal heat utilization system can suppress the abnormality of the water level in the cushion tank.

A seventh aspect is any one of the first to sixth geothermal heat utilization systems including the plurality of cushion tanks.

According to this aspect, the supply source of water to be supplied to the heat exchanger can be shared among a plurality of cushion tanks.
Therefore, water is easily supplied from the cushion tank to the heat exchanger.

An eighth aspect is based on a cushion tank connected to a hot water well and a cold water well, a heat exchanger connected to the cushion tank and exchange heat with a heat medium of a heat source machine, and a first command. A hot water pump capable of pumping water from the hot water well, a cold water pump capable of pumping water from the cold water well based on the first command, and a load pipe connecting the cushion tank and the heat exchanger. Based on the load flow rate acquisition unit that acquires the load flow rate measured by the underground heat utilization system including a load flow meter that measures the load flow rate, which is the flow rate of water flowing through the load piping, and the load flow rate. It is a control device including a first specific unit that specifies the first command and a first command unit that sends the first command to the hot water pump or the cold water pump.

According to this aspect, the control device controls the hot water pump or the cold water pump based on the load flow rate.
Therefore, the control device can suppress the fluctuation of the water level in the cushion tank.
Therefore, the control device can suppress fluctuations in the flow rate of water supplied to the heat exchanger.

A ninth aspect is based on a cushion tank connected to a hot water well and a cold water well, a heat exchanger connected to the cushion tank and exchanging heat with a heat medium of a heat source machine, and a first command. A hot water pump capable of pumping water from the hot water well, a cold water pump capable of pumping water from the cold water well based on the first command, and a load pipe connecting the cushion tank and the heat exchanger. Based on the step of acquiring the load flow rate measured by the underground heat utilization system including a load flow meter for measuring the load flow rate which is the flow rate of water flowing through the load pipe, and the load flow rate, the first It is a control method including a step of specifying a command and a step of sending the first command to the hot water pump or the cold water pump.

According to this aspect, the control method controls the hot water pump or the cold water pump based on the load flow rate.
Therefore, the control method can suppress the fluctuation of the water level in the cushion tank.
Therefore, the control method can suppress fluctuations in the flow rate of water supplied to the heat exchanger.

A tenth aspect is based on a cushion tank connected to a hot water well and a cold water well, a heat exchanger connected to the cushion tank and exchanging heat with a heat medium of a heat source machine, and a first command. A hot water pump capable of pumping water from the hot water well, a cold water pump capable of pumping water from the cold water well based on the first command, and a load pipe connecting the cushion tank and the heat exchanger. Based on the step of acquiring the measured load flow rate and the load flow rate on the computer of the underground heat utilization system including the load flow meter for measuring the load flow rate which is the flow rate of the water flowing through the load piping. It is a program for executing the step of specifying the first command and the step of sending the first command to the hot water pump or the cold water pump.

According to this aspect, the hot water pump or the cold water pump is controlled based on the load flow rate.
Therefore, the geothermal heat utilization system can suppress the fluctuation of the water level in the cushion tank connected to the heat exchanger.
Therefore, the geothermal heat utilization system can suppress fluctuations in the flow rate of water supplied to the heat exchanger.

According to the above aspect, fluctuations in the flow rate of water supplied to the heat exchanger can be suppressed.

It is a system diagram of the geothermal heat utilization system in the first embodiment. It is a block diagram of the control device in 1st Embodiment. It is a block diagram of the hot water side valve and the cold water side valve in 1st Embodiment. It is a figure which shows the operation at the time of using the heat of the underground heat utilization system in 1st Embodiment. It is a flowchart of the control method of 1st Embodiment. It is a figure which shows the operation at the time of using the cold heat of the underground heat utilization system in 1st Embodiment. It is a system diagram of the geothermal heat utilization system in the second embodiment. It is a system diagram of the geothermal heat utilization system in the third embodiment (at the time of cold heat utilization). It is a system diagram of the geothermal heat utilization system in the 4th Embodiment (in the case of cold heat utilization). It is a system diagram of the underground heat utilization system in the 4th Embodiment (at the time of thermal utilization). It is a system diagram of the geothermal heat utilization system in the fifth embodiment (at the time of cold heat utilization). It is a system diagram of the geothermal heat utilization system in the fifth embodiment (at the time of thermal utilization). This is an example of the hardware configuration of the computer included in the control device according to each embodiment.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings. The same or corresponding configurations are designated by the same reference numerals in all drawings, and common description will be omitted.

<First Embodiment>
The first embodiment of the geothermal heat utilization system according to the present invention will be described with reference to FIGS. 1 to 6.

(Configuration of geothermal heat utilization system)
The geothermal heat utilization system 10 stores heat in the aquifer LY.
The underground heat utilization system 10 is configured to pump water from the aquifer LY and circulate the water heat-exchanged with the heat medium to the aquifer LY.
As shown in FIG. 1, the geothermal heat utilization system 10 includes a cushion tank 20, a heat exchanger 30, a hot water pump 40, a cold water pump 50, a load pipe 60L, a load flow meter 70L, and a control device 80. And.
For example, the geothermal heat utilization system 10 includes a hot water well WLH, a cold water well WLC, a hot water pipe 60H, a cold water pipe 60C, a hot water flow meter 70H, a cold water flow meter 70C, a hot water side valve 90H, and a cold water side. A valve 90C and a load pump 95 may be further provided.
The geothermal heat utilization system 10 exchanges heat with the heat medium of the heat source machine R. For example, the heat source machine R is a heating facility or a cooling facility in a building.
The geothermal heat utilization system 10 may be configured to pump water from the hot water well WLH and recirculate the water heat-exchanged with the heat medium to the cold water well WLC.
The geothermal heat utilization system 10 may be configured to pump water from the cold water well WLC and recirculate the water heat-exchanged with the heat medium to the hot water well WLH.
The insides of the cushion tank 20, the load pipe 60L, the hot water pipe 60H, and the cold water pipe 60C may be maintained at atmospheric pressure or higher.

(Hot water well)
The hot water well WLH is a well extending into the aquifer LY from above ground to underground.
For example, the hot water well WLH includes a casing CS embedded in an excavation hole excavated underground from the surface SG to the aquifer LY.
The casing CS has an opening HOL in the aquifer LY.
The geothermal heat utilization system 10 is configured by the opening HOL so that the water stored in the aquifer LY can be taken into the casing CS and the water can be returned from the inside of the casing CS to the aquifer LY. There is.
The geothermal heat utilization system 10 can move water back and forth between the casing CS and the aquifer LY.
For example, the geothermal heat utilization system 10 may include a plurality of hot water wells WLH along the surface SG.

(Cold water well)
The chilled water well WLC is a well extending into the aquifer LY from above ground to underground.
The hot water well WLH and the cold water well WLC are provided at positions separated from each other in the direction along the ground surface SG.
For example, the distance between the hot water well WLH and the cold water well WLC is so long that the cold water stored in the aquifer LY and the hot water do not interfere with each other, and the ground subsidence due to the pumping from the aquifer LY does not occur. It is set to a close distance.
For example, the cold water well WLC also includes a casing CS similar to the hot water well WLH.
As a result, the geothermal heat utilization system 10 is configured so that the water stored in the aquifer LY can be taken into the casing CS and the water can be returned from the inside of the casing CS to the aquifer LY. ..
For example, the geothermal heat utilization system 10 can move cold water back and forth between the casing CS and the aquifer LY.
For example, the geothermal heat utilization system 10 may include a plurality of cold water wells WLCs along the surface SG.

(Cushion tank)
The cushion tank 20 is connected to the hot water well WLH and the cold water well WLC.
In the present embodiment, the cushion tank 20 is a temperature stratified heat storage tank. That is, in the cushion tank 20, hot water is stored above the temperature boundary layer BL, and a cold water heat source is stored below the temperature boundary layer BL. In the cushion tank 20, the temperature boundary layer BL is a boundary between hot water and cold water, and rises when hot water increases and cold water decreases, and decreases when cold water decreases and hot water increases.
For example, the cushion tank 20 may include a hot water port 20a into which hot water flows in and out, and a cold water port 20b in which cold water flows in and out.

Here, "hot water" means water having a temperature higher than the initial underground temperature of the water in the aquifer LY, and "cold water" means water having a temperature lower than the initial underground temperature of the water in the aquifer LY. It refers to water.
For example, the initial underground temperature of water in an aquifer is 18 ° C.
For example, the geothermal heat utilization system 10 stores hot water at 23 ° C. in the aquifer LY around the hot water well WLH and stores cold water at 13 ° C. in the aquifer LY around the cold water well WLC except for the first year. There is.

For example, the cushion tank 20 and the hot water well WLH may be connected by the hot water pipe 60H.
At that time, the hot water pumped into the hot water well WLH can be sent into the cushion tank 20 by the hot water pipe 60H.
Further, the hot water pipe 60H can send the hot water inside the cushion tank 20 into the hot water well WLH.
When the geothermal heat utilization system 10 includes a plurality of hot water wells WLH, the hot water pipe 60H may be branched from the cushion tank 20 toward each hot water well WLH and connected to the plurality of hot water wells WLH.

For example, the cushion tank 20 and the chilled water well WLC may be connected by a chilled water pipe 60C.
At that time, the cold water pumped into the cold water well WLC can be sent into the cushion tank 20 by the cold water pipe 60C.
Further, the cold water pipe 60C can send the cold water inside the cushion tank 20 into the cold water well WLC.
When the geothermal heat utilization system 10 includes a plurality of chilled water wells WLCs, the hot water pipe 60H may be branched from the cushion tank 20 toward each chilled water well WLC and connected to the plurality of hot water wells WLHs.

For example, the cushion tank 20 may include a thermometer 21.
At that time, the thermometer 21 measures the temperature of water at a predetermined water level in the cushion tank.
Further, a thermometer 21 may be provided at each of the three water levels of high water level, medium water level, and low water level in the cushion tank.

(Heat exchanger)
The heat exchanger 30 is connected to the cushion tank 20.
The heat exchanger 30 includes a primary side pipe 30a on the primary side and a secondary side pipe 30b on the secondary side.
The heat exchanger 30 exchanges heat between the water flowing through the primary side pipe 30a and the heat medium of the heat source machine R flowing through the secondary side pipe 30b.
In the present embodiment, the heat exchanger 30 returns the water flowing to the primary side with a temperature difference of + 5 ° C. or −5 ° C. with respect to the initial underground temperature (= 18 ° C.).
For example, when the heat source machine R heats, the heat exchanger 30 converts the hot water at 23 ° C. flowing from the cushion tank 20 into cold water at 13 ° C. by heat exchange and returns it to the cushion tank 20.
For example, when the heat source machine R cools, the heat exchanger 30 converts the cold water at 13 ° C. flowing from the cushion tank 20 into hot water at 23 ° C. by heat exchange and returns it to the cushion tank 20.
For example, the geothermal heat utilization system 10 may include a plurality of heat exchangers 30.
For example, the load pipe 60L may connect the heat exchanger 30 and the cushion tank 20.

(Load piping)
The load pipe 60L is a pipe that extends from the hot water port 20a and returns to the cold water port 20b.
In the present embodiment, the load pipe 60L extends from the hot water port 20a toward the branch point 60a closest to the hot water port 20a, and branches and extends from the branch point 60a toward each heat exchanger 30.
Further, the load pipe 60L extends from the chilled water port 20b toward the branch point 60b closest to the chilled water port 20b, and branches and extends from the branch point 60b toward each heat exchanger 30.
For example, the primary side (primary side pipe 30a) of each heat exchanger 30 is connected in the middle of the load pipe 60L that branches and extends from the branch point 60a toward each heat exchanger 30 and returns to the branch point 60b. You may.
In FIG. 1, there is no bypass not passing through the cushion tank 20 between the hot water well WLH and the cold water well WLC and each heat exchanger 30, and only the path passing through the cushion tank 20 is shown. A bypass that does not pass through the cushion tank 20 may be provided between the hot water well WLH and the cold water well WLC and each heat exchanger 30.

(Hot water pump)
The hot water pump 40 can pump water from the hot water well WLH based on the first command C1 from the control device 80.
The hot water pump 40 is provided in each hot water well WLH.
When the hot water pump 40 is operated, the hot water well WLH becomes a negative pressure, and the water stored in the aquifer LY is taken into the casing CS through the opening HOL.
The hot water pump 40 is provided with an inverter or the like, and the pump output is controlled according to the input first command C1. As a result, the hot water pump 40 can pump hot water from the aquifer LY through the casing CS of the hot water well WLH at the pump output in accordance with the first command C1.

(Cold water pump)
The chilled water pump 50 can pump water from the chilled water well WLC based on the first command C1 from the control device 80.
The chilled water pump 50 is provided in each chilled water well WLC.
When the chilled water pump 50 is operated, the chilled water well WLC becomes a negative pressure, and the water stored in the aquifer LY is taken into the casing CS through the opening HOL.
The chilled water pump 50 is provided with an inverter or the like, and the pump output is controlled according to the input first command C1. As a result, the chilled water pump 50 can pump chilled water from the aquifer LY through the casing CS of the chilled water well WLC at the pump output in accordance with the first command C1.

(Load flow meter)
The load flow meter 70L measures the load flow rate FL, which is the flow rate of water flowing through the load pipe 60L.
For example, even if a load flow meter 70L is provided between the hot water port 20a and the branch point 60a in the load pipe 60L and measures the flow rate of water flowing through the load pipe 60L between the hot water port 20a and the branch point 60a. Good. Here, the water flowing out of the cushion tank 20 circulates in the load pipe 60L and flows into the cushion tank 20 again. Therefore, the load flow rate FL measured by the load flow meter 70L also corresponds to the flow rate of water flowing through the load pipe 60L between the branch point 60b and the chilled water port 20b.

(Hot water flow meter)
The hot water flow meter 70H measures the hot water flow rate FH, which is the flow rate of hot water flowing through the hot water pipe 60H.
In FIG. 1, the hot water flow meter 70H is provided in a pipe of the hot water pipe 60H where all the branches from the plurality of hot water wells WLH merge and go to the cushion tank 20.
As a result, the hot water flow meter 70H can measure the total flow rate FSH of hot water flowing into the cushion tank 20 from the plurality of hot water wells WLH.

(Cold water flow meter)
The chilled water flow meter 70C measures the chilled water flow rate FC, which is the flow rate of chilled water flowing through the chilled water pipe 60C.
In FIG. 1, the chilled water flow meter 70C is provided in a pipe of the chilled water pipe 60C where all the branches from the plurality of chilled water wells WLCs merge and go to the cushion tank 20.
As a result, the chilled water flow meter 70C can measure the total flow rate FSC of chilled water flowing into the cushion tank 20 from the plurality of chilled water wells WLC.

(Control device)
As shown in FIG. 2, the control device 80 includes a Central Processing Unit (hereinafter, referred to as “CPU”) 100.
The CPU 100 functionally includes a load flow rate acquisition unit 81, a first specific unit 82, and a first command unit 83.
The CPU 100 further functionally includes a hot water flow rate acquisition unit 84 and a cold water flow rate acquisition unit 85.
The CPU 100 further functionally includes a temperature acquisition unit 86, a second specific unit 87, and a second command unit 88.

The load flow rate acquisition unit 81 acquires the load flow rate FL.
The first identification unit 82 identifies the first command C1 based on the load flow rate FL.
The first command unit 83 sends the first command C1 to the hot water pump 40 or the cold water pump 50.

For example, the load flow rate acquisition unit 81 may acquire the flow rate of hot water flowing out of the cushion tank 20 as the load flow rate FL.
At that time, the first specific unit 82 identifies the first command C1 based on the load flow rate FL and the hot water flow rate FH, and the first command unit 83 sends the first command C1 to the hot water pump 40.
Further, the first specific unit 82 may specify the first command C1 so that the load flow rate FL and the total flow rate FSH of the water flowing through the hot water pipe 60H are balanced.
In this case, the load flow rate acquisition unit 81 may calculate the time average of the flow rate of the hot water flowing out from the cushion tank 20 as the load flow rate FL.
At that time, the first specific unit 82 may specify the first command C1 so that the load flow rate FL (which is the time average) and the time average of the total flow rate FSH are balanced.

For example, the load flow rate acquisition unit 81 may acquire the flow rate of hot water flowing into the cushion tank 20 as the load flow rate FL.
At that time, the first specific unit 82 identifies the first command C1 based on the load flow rate FL and the chilled water flow rate FC, and the first command unit 83 sends the first command C1 to the chilled water pump 50.
Further, the first specific unit 82 may specify the first command C1 so that the load flow rate FL and the total flow rate FSC of the water flowing through the cold water pipe 60C are balanced.
In this case, the load flow rate acquisition unit 81 may calculate the time average of the flow rate of the hot water flowing from the cushion tank 20 as the load flow rate FL.
At that time, the first specific unit 82 may specify the first command C1 so that the load flow rate FL (which is the time average) and the time average of the total flow rate FSC are balanced.

The hot water flow rate acquisition unit 84 acquires the total flow rate FSH.
In the case of the present embodiment, since the hot water flow rate FH measured by the hot water flow meter 70H corresponds to the total flow rate FSH, the hot water flow rate acquisition unit 84 acquires the hot water flow rate FH as the total flow rate FSH.

The chilled water flow rate acquisition unit 85 acquires the total flow rate FSC of chilled water flowing through the chilled water pipe 60C.
In the case of this embodiment, since the chilled water flow rate FC measured by the chilled water flow meter 70C corresponds to the total flow rate FSC, the chilled water flow rate acquisition unit 85 acquires the chilled water flow rate FC as the total flow rate FSC.

The temperature acquisition unit 86 acquires the temperature measured by the thermometer 21.
For example, the temperature acquisition unit 86 may acquire the temperature TP measured by the thermometer 21 provided at each water level among the three water levels of high water level, medium water level, and low water level.

The second identification unit 87 identifies the second command C2 based on the measured temperature TP.
For example, the second specific unit 87 is hot water set from a thermometer 21 provided at the high water level (or medium water level) among the three water levels of the high water level, the medium water level, and the low water level in the cushion tank 20. It is assumed that a temperature lower than the temperature of (for example, 23 ° C.) is detected. In this case, since the temperature boundary layer BL in the cushion tank 20 may rise abnormally, the second specific unit 87 issues a command to the hot water pump 40 to increase the pump output as much as possible. Specified as Directive C2.
For example, the second specific unit 87 is cold water set from a thermometer 21 provided at the low water level (or medium water level) among the three water levels of the high water level, the medium water level, and the low water level in the cushion tank 20. It is assumed that a temperature higher than the temperature of (for example, 13 ° C.) is detected. In this case, since the temperature boundary layer BL in the cushion tank 20 may drop abnormally, the second specific unit 87 issues a command to the cold water pump 50 to increase the pump output as much as possible. Specified as Directive C2.

The second command unit 88 sends the second command C2 to the hot water pump 40 or the cold water pump 50.

(Hot water side valve)
On the hot water well WLH side, the hot water side valve 90H is provided at a connection point between the hot water pipe 60H and the hot water pump 40.
The hot water side valve 90H is configured to allow the water in the casing CS sucked up by the hot water pump 40 to flow toward the hot water pipe 60H.
Further, the hot water side valve 90H is configured to open the water flowing from the hot water pipe 60H toward the hot water well WLH into the casing CS.
For example, as shown in FIG. 3, the hot water side valve 90H can be configured by a combination of a three-way valve VL1 which is a water injection valve and a check valve VL2. The check valve VL2 is provided so that water flows from the hot water pump 40 toward the hot water pipe 60H and does not flow from the hot water pipe 60H toward the hot water pump 40. Further, the three-way valve VL1 releases the water in the hot water pipe 60H from the hot water pipe 60H toward the casing CS when the pressure in the hot water pipe 60H becomes larger than the set pressure.

(Cold water side valve)
On the chilled water well WLC side, the chilled water side valve 90C is provided at a connection point between the chilled water pipe 60C and the chilled water pump 50.
The chilled water side valve 90C is configured so that the water in the casing CS sucked up by the chilled water pump 50 flows toward the chilled water pipe 60C.
Further, the cold water side valve 90C is configured to open the water flowing from the cold water pipe 60C toward the cold water well WLC into the casing CS.
For example, as shown in FIG. 3, the cold water side valve 90C can be configured by a combination of a three-way valve VL1 which is a water injection valve and a check valve VL2. The check valve VL2 is provided so that water does not flow from the chilled water pump 50 toward the chilled water pipe 60C and does not flow from the chilled water pipe 60C toward the chilled water pump 50. Further, the three-way valve VL1 releases the water in the chilled water pipe 60C from the chilled water pipe 60C toward the casing CS when the pressure in the chilled water pipe 60C becomes larger than the set pressure.

(Load pump)
The heat exchanger 30 is connected to the load pipe 60L via the load pump 95.
The load pump 95 sucks the water in the load pipe 60L toward the heat exchanger 30.
On the contrary, the load pump 95 sucks water from the primary side pipe 30a of the heat exchanger 30 toward the load pipe 60L.
For example, when the load pipe 60L is connected to a plurality of heat exchangers 30, a load pump 95 may be provided in connection with each heat exchanger 30.

(Operation 1)
For example, the operation of the geothermal heat utilization system 10 when the heat source machine R mainly performs heating will be described with reference to FIG.
In FIG. 4, the arrows indicate the flow of heat medium and water in each portion.
Further, in FIG. 4, the white-painted arrow indicates cold water, and the black-painted arrow indicates hot water.

First, the load pump 95 sucks hot water in the load pipe 60L toward the heat exchanger 30.
As a result, hot water is supplied from the cushion tank 20 toward the load pipe 60L.
When hot water is supplied toward the load pipe 60L, water is supplied from the aquifer LY by the hot water pump 40 to the upper side of the temperature boundary layer BL in the cushion tank 20 through the hot water pipe 60H.
Here, the geothermal heat utilization system 10 supplies water having an initial underground temperature to the cushion tank 20 in the first year after starting the operation, but supplies hot water to the cushion tank 20 from the second year onward. It will be.

At this time, the control device 80 operates as shown in FIG. This operation corresponds to the control method of the geothermal heat utilization system 10.

First, the control device 80 acquires the measured load flow rate FL (ST01: step of acquiring the load flow rate).
In the case of FIG. 4, the load flow rate acquisition unit 81 acquires the flow rate of hot water flowing out from the cushion tank 20 to the load pipe 60L as the load flow rate FL from the load flow meter 70L.

After executing ST01, the control device 80 identifies the first command C1 based on the load flow rate FL (ST02: step of specifying the first command).
For example, the first specifying unit 82 specifies the first command C1 so that the load flow rate FL and the total flow rate FSH of the water flowing through the hot water pipe 60H are balanced.
In the case of FIG. 4, since the hot water flow meter 70H can measure the total flow rate FSH of the hot water flowing into the cushion tank 20 from the plurality of hot water wells WLH, the first specific unit 82 is from the load flow rate FL and the hot water flow meter 70H. The first command C1 is specified so as to balance the acquired hot water flow rate FH.
For example, when the load flow rate FL is larger than the hot water flow rate FH (total flow rate FSH), the first specifying unit 82 specifies a command for increasing the pump output (output of the hot water pump 40) as the first command C1.
For example, when the load flow rate FL is smaller than the hot water flow rate FH (total flow rate FSH), the first specifying unit 82 specifies a command for reducing the pump output (output of the hot water pump 40) as the first command C1.

After executing ST02, the control device 80 sends the first command C1 to the hot water pump 40 or the cold water pump 50 (ST03: step of sending the first command).
In the case of FIG. 4, the first command unit 83 sends the first command C1 to the hot water pump 40.
After performing ST03, the control device 80 may return to ST02 in order to perform feedback control.

(Operation 2)
For example, the operation of the geothermal heat utilization system 10 when the heat source machine R mainly performs cooling will be described with reference to FIG.

First, the load pump 95 sucks the cold water in the load pipe 60L toward the heat exchanger 30.
As a result, cold water is supplied from the cushion tank 20 toward the load pipe 60L.
When cold water is supplied toward the load pipe 60L, water is supplied from the aquifer LY by the cold water pump 50 to the lower side of the temperature boundary layer BL in the cushion tank 20 through the cold water pipe 60C.
Here, the geothermal heat utilization system 10 supplies water at the initial underground temperature to the cushion tank 20 in the first year after starting the operation, but supplies cold water to the cushion tank 20 from the second year onward. It will be.
At this time, the control device 80 operates as shown in FIG. This operation corresponds to the control method of the geothermal heat utilization system 10.

First, the control device 80 acquires the measured load flow rate FL (ST01: step of acquiring the load flow rate).
In FIG. 6, the load flow rate acquisition unit 81 acquires the flow rate of hot water flowing from the cushion tank 20 into the load pipe 60L from the load flow meter 70L as the load flow rate FL.

After executing ST01, the control device 80 identifies the first command C1 based on the load flow rate FL (ST02: step of specifying the first command).
For example, the first specifying unit 82 specifies the first command C1 so that the load flow rate FL and the total flow rate FSH of the water flowing through the chilled water pipe 60C are balanced.
In the case of FIG. 6, since the chilled water flow meter 70C can measure the total flow rate FSH of the chilled water flowing into the cushion tank 20 from the plurality of chilled water wells WLC, the first specific unit 82 is from the load flow rate FL and the chilled water flow meter 70C. The first command C1 is specified so as to balance the acquired cold water flow rate FC.
For example, when the load flow rate FL is larger than the chilled water flow rate FC (total flow rate FSC), the first specifying unit 82 specifies a command for increasing the pump output (output of the chilled water pump 50) as the first command C1.
For example, when the load flow rate FL is smaller than the hot water flow rate FH (total flow rate FSH), the first specifying unit 82 specifies a command to reduce the pump output (output of the cold water pump 50) as the first command C1.

After executing ST02, the control device 80 sends the first command C1 to the hot water pump 40 or the cold water pump 50 (ST03: step of sending the first command).
In the case of FIG. 6, the first command unit 83 sends the first command C1 to the chilled water pump 50.
After performing ST03, the control device 80 may return to ST02 in order to perform feedback control.

(Action and effect)
According to this embodiment, the hot water pump 40 or the cold water pump 50 is controlled based on the load flow rate FL of the cushion tank 20 connected to the hot water well WLH and the cold water well WLC.
Therefore, the geothermal heat utilization system 10 can suppress fluctuations in the water level in the cushion tank 20 connected to the heat exchanger 30.
Therefore, the geothermal heat utilization system 10 can suppress fluctuations in the flow rate of water supplied to the heat exchanger 30.

For example, when hot water flows out from the cushion tank 20 toward the load pipe 60L, the amount of hot water in the cushion tank 20 decreases.
When the cushion tank 20 is a temperature stratified heat storage tank as in the present embodiment, when the amount of hot water in the cushion tank 20 decreases, the temperature boundary layer BL rises and the water level in the cushion tank 20 fluctuates.
On the other hand, in the present embodiment, since the hot water pump 40 is controlled based on the load flow rate FL, the fluctuation of the water level in the cushion tank 20 can be suppressed.

For example, when cold water flows out from the cushion tank 20 toward the load pipe 60L, the amount of cold water in the cushion tank 20 decreases.
When the cushion tank 20 is a temperature stratified heat storage tank as in the present embodiment, when the amount of cold water in the cushion tank 20 decreases, the temperature boundary layer BL drops and the water level in the cushion tank 20 fluctuates.
On the other hand, in the present embodiment, since the cold water pump 50 is controlled based on the load flow rate FL, the fluctuation of the water level in the cushion tank 20 can be suppressed.

According to this embodiment, the hot water pump 40 or the cold water pump 50 is controlled based on the load flow rate FL of the cushion tank 20.
Therefore, since the load flow rate FL of the cushion tank 20 can be secured, it is possible to change the flow rate distribution of each well.

For example, if the load flow rate FL of the cushion tank 20 can be secured, it is possible to stop some of the hot water pumps 40 of the plurality of hot water wells WLH.
Similarly, if the load flow rate FL of the cushion tank 20 can be secured, it is possible to stop some of the chilled water pumps 50 among the chilled water pumps 50 of the plurality of chilled water wells WLCs.
Therefore, it is possible to stop the use of some wells and perform maintenance of the stopped wells while using the geothermal heat utilization system 10.

For example, if the load flow rate FL of the cushion tank 20 can be secured, the pumping flow rate from each hot water well WLH can be changed by alternately operating the hot water pumps 40 of the plurality of hot water wells WLH.
Similarly, if the load flow rate FL of the cushion tank 20 can be secured, it is possible to change the pumping flow rate from each chilled water well WLC by alternately operating the chilled water pumps 50 of the plurality of chilled water well WLCs.
Therefore, since the pumping flow rate can be varied, the geothermal heat utilization system 10 can avoid the operation of a continuous constant flow rate that tends to lead to clogging of the well.

According to this embodiment, the hot water pump 40 is controlled based on the load flow rate FL and the hot water flow rate FH.
Therefore, the geothermal heat utilization system 10 can absorb fluctuations in the load flow rate in the cushion tank 20 and suppress fluctuations in the water level in the cushion tank 20.

According to the present embodiment, the amount of hot water corresponding to the hot water flowing out from the cushion tank 20 can be supplied from the plurality of hot water wells WLH.
Therefore, the geothermal heat utilization system 10 uses the hot water flowing out of the cushion tank 20 as the other hot water even if the amount of hot water supplied from the hot water well WLH among the plurality of hot water wells WLH fluctuates or is limited. It can be compensated by the well WLH.
For example, even when the use of one of the hot water wells WLH is stopped for maintenance, or when the pumping flow rate from each hot water well WLH is changed to avoid clogging of the wells, the cushion tank The hot water flowing out from 20 can be compensated by another hot water well WLH.
Therefore, the geothermal heat utilization system 10 can suppress fluctuations in the amount of hot water in the cushion tank 20.

According to this embodiment, the chilled water pump 50 is controlled based on the load flow rate FL and the chilled water flow rate FC.
Therefore, the geothermal heat utilization system 10 can suppress fluctuations in the amount of cold water in the cushion tank 20.

According to this embodiment, the amount of cold water corresponding to the cold water flowing out from the cushion tank 20 can be supplied from the plurality of cold water wells WLCs.
Therefore, the geothermal heat utilization system 10 uses the cold water flowing out of the cushion tank 20 as the other cold water even if the supply amount of the cold water from the cold water well WLC among the plurality of cold water well WLCs fluctuates or is limited. It can be compensated by the well WLC.
For example, even when the use of one of the cold water well WLCs is stopped for maintenance, or when the pumping flow rate from each cold water well WLC is changed to avoid clogging of the wells, the cushion tank The cold water flowing out from 20 can be compensated by another cold water well WLC.
Therefore, the geothermal heat utilization system 10 can suppress fluctuations in the amount of cold water in the cushion tank 20.

According to this embodiment, the hot water pump 40 or the cold water pump 50 is controlled based on the temperature of water at a predetermined water level in the cushion tank 20.
Therefore, the geothermal heat utilization system 10 can suppress an abnormality in the water level in the cushion tank 20.

(Modification example)
In the present embodiment, the hot water flow meter 70H is provided in the pipe toward the cushion tank 20 where all the branches from the plurality of hot water wells WLH merge in the hot water pipe 60H, so that the hot water flow rate acquisition unit 84 is totaled. Although the flow rate FSH has been acquired, any configuration may be used as long as the total flow rate FSH can be acquired.
As a modification, the hot water flow rate acquisition unit 84 acquires each flow rate measured in the piping at the branch destination to the plurality of hot water wells WLH among the hot water pipes 60H, and calculates the total flow rate of each flow rate to calculate the total flow rate. FSH may be acquired.

In the present embodiment, the chilled water flow meter 70C is provided in the pipe toward the cushion tank 20 where all the branches from the plurality of chilled water wells WLCs merge in the chilled water pipe 60C, so that the chilled water flow rate acquisition unit 85 is totaled. Although the flow rate FSC is acquired, any configuration may be used as long as the total flow rate FSC can be acquired.
As a modification, the chilled water flow rate acquisition unit 85 acquires each flow rate measured in the pipes of the branch destinations to the plurality of chilled water wells WLCs in the chilled water pipe 60C, and calculates the total flow rate of each flow rate. FSH may be acquired.

In the present embodiment, the first specifying unit 82 specifies the first command C1 so that the load flow rate FL and the total flow rate FSH are balanced, but what if the load flow rate FL and the total flow rate FSH are balanced? The first directive C1 may be specified.
As a modification, the first specific unit 82 may specify the first command C1 so as to satisfy the following equation (1).

ΣFL = ΣFSH ... (1)

In addition, Σ of the formula (1) means time integration over a predetermined time.

In the present embodiment, the first specific unit 82 specifies the first command C1 so that the load flow rate FL and the total flow rate FSC are balanced, but what if the load flow rate FL and the total flow rate FSC are balanced? The first directive C1 may be specified.
As a modification, the first specific unit 82 may specify the first command C1 so as to satisfy the following equation (2).

ΣFL = ΣFSC ... (2)

In addition, Σ of the formula (2) means time integration over a predetermined time.

In the present embodiment, the load flow meter 70L is provided between the hot water port 20a and the branch point 60a in the load pipe 60L, but it may be provided in any way as long as the load flow rate FL can be measured.
As a modification, the load flow meter 70L may be provided between the chilled water port 20b and the branch point 60b in the load pipe 60L.

In the present embodiment, the hot water side valve 90H is composed of a combination of a three-way valve VL1 which is a water injection valve and a check valve VL2, and the water sucked up by the hot water pump 40 flows toward the hot water pipe 60H. Any configuration may be used as long as the water flowing from the hot water pipe 60H can be released into the casing CS.
As a modification, the hot water side valve 90H is controlled to circulate only from the hot water pump 40 toward the hot water pipe 60H when the hot water pump 40 is driven, and to circulate only from the hot water pipe 60H toward the casing CS when the hot water pump 40 is stopped. It may be a valve.

In the present embodiment, the cold water side valve 90C is composed of a combination of a three-way valve VL1 which is a water injection valve and a check valve VL2, and the water sucked up by the cold water pump 50 flows toward the cold water pipe 60C. Any configuration may be used as long as the water flowing from the cold water pipe 60C can be released into the casing CS.
As a modification, the chilled water side valve 90C controls to circulate only from the chilled water pump 50 toward the chilled water pipe 60C when the chilled water pump 50 is driven, and to circulate only from the chilled water pipe 60C toward the casing CS when the chilled water pump 50 is stopped. It may be a valve.

In the present embodiment, the control device 80 sends the first command C1 or the second command C2 to the hot water pump 40, but as a modification, when there are a plurality of hot water pumps 40, the control device 80 sends the first command. As C1 or the second command C2, different commands may be sent for each hot water pump 40.
As another modification, when there are a plurality of hot water pumps 40, the control device 80 receives the first command C1 or the second command C2 to only a part of the hot water pumps 40 among the plurality of hot water pumps 40. C1 or the second command C2 may be sent.

In the present embodiment, the control device 80 sends the first command C1 or the second command C2 to the chilled water pump 50, but as a modification, when there are a plurality of chilled water pumps 50, the control device 80 sends the first command. As C1 or the second command C2, different commands may be sent for each cold water pump 50.
As another modification, when there are a plurality of chilled water pumps 50, the control device 80 uses the first command C1 or the second command C2 as the first command to only a part of the chilled water pumps 50 among the plurality of chilled water pumps 50. C1 or the second command C2 may be sent.

In the present embodiment, the first specifying unit 82 specifies the first command C1 so that the load flow rate FL and the total flow rate FSH or the total flow rate FSC are balanced, but specifies based on the load flow rate FL. If so, the first directive C1 may be specified in any way.
As a modification, the geothermal heat utilization system 10 may specify the first command C1 without using the total flow rate FSH or the total flow rate FSC.
For example, the first specifying unit 82 may specify the pump output of the hot water pump 40 or the cold water pump 50 capable of supplying water having a flow rate corresponding to the load flow rate FL as the first command C1.
At that time, the control device 80 may store in advance the relationship between the pump output of each of the hot water pump 40 and the cold water pump 50 and the flow rate of water from each pump to the cushion tank 20.

<Second embodiment>
A second embodiment of the geothermal heat utilization system according to the present invention will be described with reference to FIG.
The geothermal heat utilization system 10'in FIG. 7 includes a plurality of cushion tanks 20 in addition to the configuration of the first embodiment.
According to this embodiment, the supply source of water to be supplied to the heat exchanger 30 can be shared by the plurality of cushion tanks 20.
Therefore, water is easily supplied from the cushion tank 20 to the heat exchanger.

In FIG. 7, each cushion tank 20 is connected to a pair of hot water well WLH and a cold water well WLC, but each cushion tank 20 may be connected to a plurality of hot water well WLH and a plurality of cold water well WLC. ..

<Third Embodiment>
A third embodiment of the geothermal heat utilization system according to the present invention will be described with reference to FIG.
In the geothermal heat utilization system 110 shown in FIG. 8, in addition to the configuration of the first embodiment, a bypass pipe 60B without a cushion tank 20 is provided between the hot water well WLH and the cold water well WLC and each heat exchanger 30. It is provided.
In the geothermal heat utilization system 110, the bypass pipe 60B, the load pipe 60L, the hot water pipe 60H, and the cold water pipe 60C share a pipe in a common route.

For example, in the geothermal heat utilization system 110, each heat exchanger 30 may be connected to the load pipe 60L via a throttle valve 96 instead of the load pump 95.
In FIG. 8, the geothermal heat utilization system 110 sends cold water directly from the cold water well WLC to the heat exchanger 30 by the bypass pipe 60B without going through the cushion tank 20. Further, the geothermal heat utilization system 110 sends cold water from the cold water well WLC to the cushion tank 20 by the cold water pipe 60C.
On the other hand, the geothermal heat utilization system 110 directly sends the hot water heated by the heat exchange in the heat exchanger 30 to the hot water well WLH by the bypass pipe 60B without passing through the cushion tank 20. Further, the geothermal heat utilization system 110 sends the hot water in the cushion tank 20 to the hot water well WLH by the hot water pipe 60H.
The control device 80 identifies the first command C1 based on the load flow rate FL, and sends the first command C1 to the chilled water pump 50.
For example, in order to maintain the water level of the temperature boundary layer BL located at the middle water level by default, the control device 80 issues the first command C1 so as to satisfy the following equation (3) by the first specific unit 82. You may specify and control the cold water pump 50.

ΣFL = 0 ... (3)

In addition, Σ of the formula (3) means time integration over a predetermined time.

<Fourth Embodiment>
A fourth embodiment of the geothermal heat utilization system according to the present invention will be described with reference to FIG.
In the geothermal heat utilization system 210 shown in FIG. 9, in addition to the configuration of the first embodiment, a bypass pipe 60B without a cushion tank 20 is provided between the hot water well WLH and the cold water well WLC and each heat exchanger 30. It is provided.
In the geothermal heat utilization system 210, the bypass pipe 60B, the load pipe 60L, the hot water pipe 60H, and the cold water pipe 60C share a pipe in a common route.
For example, in the geothermal heat utilization system 210, each heat exchanger 30 may be connected to the load pipe 60L via a bridge valve 97 in addition to the load pump 95.
In the bridge valve 97, a throttle valve 96 is provided in each flow path assembled in a diamond shape.

For example, when the heat source machine R mainly cools, the geothermal heat utilization system 210 pumps cold water from the cold water well WLC and hot water exchanged by the heat exchanger 30 as shown in FIG. Circulate the well WLH.
For example, when the heat source machine R mainly performs heating, the geothermal heat utilization system 210 pumps hot water from the hot water well WLH and heat-exchanged cold water in the heat exchanger 30 as cold water, as shown in FIG. The well WLC is recirculated.

<Fifth Embodiment>
A fifth embodiment of the geothermal heat utilization system according to the present invention will be described with reference to FIG.
In the first embodiment, the geothermal heat utilization system 310 shown in FIG. 11 has no bypass between the hot water well WLH and the cold water well WLC and each heat exchanger 30 without passing through the cushion tank 20, and the cushion tank 20 Has only a route through.
For example, in the geothermal heat utilization system 310, each heat exchanger 30 may be connected to the load pipe 60L via a bridge valve 97 in addition to the load pump 95.
In the bridge valve 97, a throttle valve 96 is provided in each flow path assembled in a diamond shape.

For example, when the heat source machine R mainly cools, the geothermal heat utilization system 310 pumps cold water from the cold water well WLC and hot water exchanged by the heat exchanger 30 as shown in FIG. Circulate the well WLH.
For example, when the heat source machine R mainly performs heating, the geothermal heat utilization system 310 pumps hot water from the hot water well WLH and heat-exchanged cold water in the heat exchanger 30 as cold water, as shown in FIG. The well WLC is recirculated.

In each of the above-described embodiments, a program for realizing various functions of the control device 80 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system such as a microcomputer. It is supposed that various processes are performed by executing the program. Here, the processes of various processes of the CPU of the computer system are stored in a computer-readable recording medium in the form of a program, and the various processes are performed by the computer reading and executing this program. The computer-readable recording medium refers to a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like. Further, this computer program may be distributed to a computer via a communication line, and the computer receiving the distribution may execute the program.

In each of the above-described embodiments, an example of a hardware configuration of a computer for executing a program for realizing various functions of the control device 80 will be described.

As shown in FIG. 13, the computer included in the control device 80 includes a CPU 100, a memory 101, a storage / playback device 102, an Input Output Interface (hereinafter referred to as “IO I / F”) 103, and a communication interface (hereinafter referred to as “IO I / F”). Hereinafter, it is referred to as “communication I / F”) 104.

The memory 101 is a medium such as a Random Access Memory (hereinafter, referred to as “RAM”) that temporarily stores data or the like used in a program executed by the control device 80.
The storage / playback device 102 is a device for storing data or the like in an external medium such as a CD-ROM, a DVD, or a flash memory, or playing back data or the like on the external media.
The IO I / F 103 is an interface for inputting / outputting information and the like between the control device 80 and another device.
The communication I / F 104 is an interface for communicating with other devices via a communication line such as the Internet or a dedicated communication line.

Although the embodiment of the present invention has been described above, this embodiment is shown as an example and is not intended to limit the scope of the invention. This embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. This embodiment and its modifications are included in the scope and gist of the invention as well as in the scope of the invention described in the claims and the equivalent scope thereof.

10 Geothermal utilization system 10'Ground heat utilization system 20 Cushion tank 20a Hot water port 20b Cold water port 21 Thermometer 30 Heat exchanger 30a Primary side piping 30b Secondary side piping 40 Hot water pump 50 Cold water pump 60a Branch point 60b Branch point 60B Bypass piping 60C Cold water piping 60H Hot water piping 60L Load piping 70C Cold water flow meter 70H Hot water flow meter 70L Load flow meter 80 Control device 81 Load flow acquisition unit 82 First specific unit 83 First command unit 84 Hot water flow acquisition unit 85 Cold water flow Acquisition unit 86 Temperature acquisition unit 87 Second specific unit 88 Second command unit 90C Cold water side valve 90H Hot water side valve 95 Load pump 96 Squeeze valve 97 Bridge valve 100 CPU
101 Memory 102 Storage / playback device 103 IO I / F
104 Communication I / F
110 Geothermal utilization system 210 Geothermal utilization system 310 Geothermal utilization system BL Temperature boundary layer C1 First command C2 Second command CS Casing FC Cold water flow rate FH Hot water flow rate FL Load flow rate FSC Total flow rate FSH Total flow rate HOL Opening LY Water zone R Heat source machine SG Ground surface TP Temperature VL1 Three-way valve VL2 Check valve WLC Cold water well WLH Hot water well

Claims (10)

Cushion tanks connected to hot and cold wells,
A heat exchanger connected to the cushion tank and exchanging heat with the heat medium of the heat source machine.
Based on the first directive, a hot water pump that can pump water from the hot water well,
Based on the first directive, a cold water pump capable of pumping water from the cold water well and
The load piping connecting the cushion tank and the heat exchanger,
A load flow meter that measures the load flow rate, which is the flow rate of water flowing through the load pipe,
Equipped with a control device,
The control device
A load flow rate acquisition unit that acquires the measured load flow rate,
Based on the load flow rate, the first specific unit that specifies the first command and
A geothermal heat utilization system including a first command unit that sends the first command to the hot water pump or the cold water pump. A hot water pipe connecting the cushion tank and the hot water well,
Further equipped with a hot water flow meter for measuring the hot water flow rate, which is the flow rate of hot water flowing through the hot water pipe, is provided.
As the load flow rate, the load flow rate acquisition unit acquires the flow rate of hot water flowing from the cushion tank to the load pipe or the flow rate of cold water flowing from the load pipe into the cushion tank.
The first specific unit identifies the first command based on the load flow rate and the hot water flow rate.
The geothermal heat utilization system according to claim 1, wherein the first command unit sends the first command to the hot water pump. The hot water pipe is connected to a plurality of the hot water wells.
The geothermal heat utilization system according to claim 2, wherein the first specific unit specifies the first command so that the load flow rate and the total flow rate of the hot water flowing through the hot water pipe are balanced. A cold water pipe connecting the cushion tank and the cold water well,
A chilled water flow meter that measures the chilled water flow rate, which is the flow rate of chilled water flowing through the chilled water pipe, is further provided.
The load flow rate acquisition unit acquires the flow rate of cold water flowing out of the cushion tank or the flow rate of hot water flowing into the cushion tank as the load flow rate.
The first specific unit identifies the first command based on the load flow rate and the cold water flow rate.
The geothermal heat utilization system according to claim 1, wherein the first command unit sends the first command to the cold water pump. The cold water pipe is connected to the plurality of the cold water wells,
The geothermal heat utilization system according to claim 4, wherein the first specific unit specifies the first command so that the load flow rate and the total flow rate of the cold water flowing through the cold water pipe are balanced. The cushion tank includes a thermometer that measures the temperature of water at a predetermined water level in the cushion tank.
The control device
Based on the measured temperature, the second specific part that specifies the second command and
The geothermal heat utilization system according to any one of claims 1 to 5, further comprising a second command unit that sends the second command to the hot water pump or the cold water pump. The geothermal heat utilization system according to any one of claims 1 to 6, further comprising the plurality of cushion tanks. Cushion tanks connected to hot and cold wells,
A heat exchanger connected to the cushion tank and exchanging heat with the heat medium of the heat source machine.
Based on the first directive, a hot water pump that can pump water from the hot water well,
Based on the first directive, a cold water pump capable of pumping water from the cold water well and
The load piping connecting the cushion tank and the heat exchanger,
A load flow meter that measures the load flow rate, which is the flow rate of water flowing through the load pipe, and a load flow rate acquisition unit that acquires the load flow rate measured by the geothermal heat utilization system.
Based on the load flow rate, the first specific unit that specifies the first command and
A control device including a first command unit that sends the first command to the hot water pump or the cold water pump. Cushion tanks connected to hot and cold wells,
A heat exchanger connected to the cushion tank and exchanging heat with the heat medium of the heat source machine.
Based on the first directive, a hot water pump that can pump water from the hot water well,
Based on the first directive, a cold water pump capable of pumping water from the cold water well and
The load piping connecting the cushion tank and the heat exchanger,
A load flow meter that measures the load flow rate, which is the flow rate of water flowing through the load pipe, and a step of acquiring the load flow rate measured by a geothermal heat utilization system including the load flow meter.
The step of identifying the first command based on the load flow rate and
A control method comprising the step of sending the first command to the hot water pump or the cold water pump. Cushion tanks connected to hot and cold wells,
A heat exchanger connected to the cushion tank and exchanging heat with the heat medium of the heat source machine.
Based on the first directive, a hot water pump that can pump water from the hot water well,
Based on the first directive, a cold water pump capable of pumping water from the cold water well and
The load piping connecting the cushion tank and the heat exchanger,
A computer of a geothermal heat utilization system equipped with a load flow meter for measuring a load flow rate, which is the flow rate of water flowing through the load pipe,
The step of acquiring the measured load flow rate and
The step of identifying the first command based on the load flow rate and
A program for executing the step of sending the first command to the hot water pump or the cold water pump.

Images