JP2023149312A - Controller, underground heat utilization system, control method and program - Google Patents

Abstract

To provide a controller that easily maintain heat balance and volume balance throughout the year, an underground heat utilization system, a control method and a program.SOLUTION: A controller comprises: a material balance control unit that controls a heat source well facility comprising a hot water well and a cold water well so that an annual pumped water volume and an annual returned water volume of each of the hot water well and the cold water well are equal; and a heat balance control unit that controls a heat storage auxiliary facility including at least one of a heating device and a cooling device so that an annual heat amount of pumped water and an annual heat amount of returned water of both the hot water well and the cold water well are equal.SELECTED DRAWING: Figure 3

Description

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

In recent years, geothermal heat utilization systems that utilize heat stored in wells have been proposed.

As a related technology, for example, Patent Document 1 discloses a geothermal heat utilization system that utilizes hot water and cold water stored in a plurality of wells extending into an aquifer.

Japanese Patent Application Publication No. 11-325650

The geothermal heat utilization system disclosed in Patent Document 1 cools hot water via a cooling tower etc. in the case of a building with a biased cooling load, and cools hot water through a cooling tower etc. in the case of a building with a biased heating load. Wells are being restored by heating cold water, such as through solar heat.
However, in the geothermal heat utilization system disclosed in Patent Document 1, the heat balance and volume balance may not be maintained throughout the year.

The present disclosure has been made in order to solve the above problems, and aims to provide a control device, a geothermal heat utilization system, a control method, and a program that can easily maintain heat balance and volume balance throughout the year. purpose.

In order to solve the above problems, a control device according to the present disclosure controls a heat source well equipment including a hot water well and a cold water well to determine the annual pumped water volume and return water volume of each well of the hot water well and the cold water well. A heat storage auxiliary equipment including at least one of a heating device and a cooling device, a material balance control unit that controls the material balance to be equal to each other, and a heat storage auxiliary equipment including at least one of a heating device and a cooling device. and a thermal balance control section that controls the temperature to be equal to the temperature.

The control method according to the present disclosure controls a heat source well equipment including a hot water well and a cold water well so that the annual pumped water volume and the returned water volume of each of the hot water well and the cold water well are equal, and the heat source well equipment includes a hot water well and a cold water well. A heat storage auxiliary equipment including at least one of the device and the cooling device is controlled so that the heat amount of pumped water and the heat amount of returned water in both the hot water well and the cold water well during the year are equalized.

A program according to the present disclosure causes a computer to control a heat source well equipment including a hot water well and a cold water well so as to equalize the pumped water volume and return water volume of each of the hot water well and the cold water well. , controlling a heat storage auxiliary equipment including at least one of a heating device and a cooling device so as to equalize the heat amount of pumped water and the heat amount of returned water in both the hot water well and the cold water well during the year; let

According to the control device, geothermal heat utilization system, control method, and program of the present disclosure, it is easy to maintain the heat balance and volume balance throughout the year.

1 is a system diagram of a geothermal heat utilization system according to an embodiment of the present disclosure. FIG. 2 is a diagram illustrating functions in an annual cycle of a geothermal heat utilization system according to an embodiment of the present disclosure. FIG. 1 is a block diagram of a control device according to an embodiment of the present disclosure. 3 is a flowchart of a control method according to an embodiment of the present disclosure. It is a figure showing the relationship between return water temperature and pumped water temperature in an annual cycle.

Embodiments according to the present disclosure will be described below with reference to the drawings. In all the drawings, the same or corresponding structures are given the same reference numerals, and common explanations are omitted.

<Embodiment>
An embodiment of a geothermal heat utilization system according to the present disclosure will be described with reference to FIGS. 1 to 5.
(Configuration of geothermal heat utilization system)
As shown in FIG. 1, the geothermal heat utilization system 1 includes a heat source well facility 10, a heat storage auxiliary facility 20, a heat pump 30, a heat exchanger 40, and a control device 50.
When the heat load LD (eg, air conditioning load) uses heating, the geothermal heat utilization system 1 uses the hot water stored in the heat source well equipment 10 for heating, and at the same time stores exhaust cold heat.
When the heat load LD uses air conditioning, the geothermal heat utilization system 1 uses the cold heat of the cold water stored in the heat source well equipment 10 for cooling, and at the same time stores waste heat.

(Configuration of heat source well equipment)
The heat source well equipment 10 includes a hot water well 11, a cold water well 12, and piping 13.

The hot water well 11 and the cold water well 12 each extend from the ground into the aquifer LY.
The hot water well 11 and the cold water well 12 are each equipped with a casing having a screen, etc., so that they can take in groundwater from the aquifer LY and return groundwater from the inside of the hot water well 11 and the cold water well 12 to the aquifer LY. It is configured.
During steady operation of the geothermal heat utilization system 1, hot water is stored in the aquifer LY around the hot water well 11, and cold water is stored in the aquifer LY around the cold water well 12.
The hot water well 11 and the cold water well 12 are provided at a sufficient distance from each other so that the stored hot water and cold water do not mix.

In the geothermal heat utilization system 1, the heat source well equipment 10 pumps groundwater to the ground from one of the hot water well 11 and the cold water well 12, performs heat exchange above ground for heat utilization and supplementary heat storage, and pumps groundwater to the ground from one of the hot water well 11 and the cold water well 12, and performs heat exchange on the ground for heat utilization and supplementary heat storage. 11 and the other of cold water well 12. That is, the heat source well equipment 10 has two operating modes: one in which groundwater is pumped up from the hot water well 11 and injected into the cold water well 12, and the other in which groundwater is pumped up from the cold water well 12 and injected into the hot water well 11.

Piping 13 connects hot water well 11 and cold water well 12.
A first end 131 that is one end of the pipe 13 extends inside the hot water well 11 and is immersed in groundwater inside the hot water well 11 .
A second end 132 , which is the other end of the pipe 13 , extends into the cold water well 12 and is immersed in groundwater inside the cold water well 12 .

Each of the first end 131 and the second end 132 is provided with a pump PP, a regulating valve RV, a check valve CV, etc., and is configured to be able to adjust the flow rate of water in the pipe 13.
The output of the pump PP can be changed by inverter control based on a command from the control device 50.
The opening degree of the regulating valve RV can be changed by a command from the control device 50.

(Heat pump configuration)
The heat pump 30 includes a condenser, an evaporator, a compressor, etc., and is provided between the heat load LD and the pipe 13 via a heat exchanger 40.
The heat pump 30 cools or heats the medium that has undergone heat exchange with the water in the piping 13 in the heat exchanger 40. As a result, the heat pump 30 uses the hot or cold heat obtained from the water in the pipe 13 for the heat load LD, and the exhaust heat or cold heat discharged from the heat load LD via the heat exchanger 40. The water is stored in the pipe 13.

(Configuration of heat exchanger)
The heat exchanger 40 exchanges heat between the water in the pipe 13 and the medium on the heat pump 30 side and the heat storage auxiliary equipment 20 side.
Specifically, the heat exchanger 40 exchanges heat between groundwater pumped up from the hot water well 11 and flowing through the pipe 13 as water in the pipe 13 and the medium on the heat pump 30 side and the heat storage auxiliary equipment 20 side. do. The groundwater after heat exchange flows from the heat exchanger 40 through the piping 13 and is injected into the cold water well 12.
Conversely, the heat exchanger 40 exchanges heat between the groundwater pumped up from the cold water well 12 and flowing through the pipe 13 as water in the pipe 13 and the medium on the heat pump 30 side and the heat storage auxiliary equipment 20 side. The groundwater after heat exchange flows from the heat exchanger 40 through the piping 13 and is injected into the hot water well 11.
The heat exchanger 40 is provided in the middle of the pipe 13 extending above the ground.

When the water that has passed through the heat exchanger 40 is hot water, the hot water well 11 stores hot water heat.
When the water that has passed through the heat exchanger 40 is cold water, the cold water well 12 stores cold water heat.
Here, "hot water" refers to water with a temperature higher than the initial underground temperature of the groundwater in the aquifer LY, and "cold water" refers to water with a temperature lower than the initial underground temperature of the groundwater in the aquifer LY. It's about water.
For example, the initial underground temperature of the groundwater in the aquifer LY is 18°C.

(Configuration of heat storage auxiliary equipment)
The heat storage auxiliary equipment 20 cools or heats the medium that has undergone heat exchange with the water in the piping 13 using the heat exchanger 40 .
The heat storage auxiliary equipment 20 includes a heating device 201 and a cooling device 206.
In this embodiment, the heating device 201 includes a solar heat collector 202 and the cooling device 206 includes a cooling tower 207.

The cooling tower 207 cools the medium of the heat storage auxiliary equipment 20 by utilizing the heat of vaporization when water is brought into contact with the atmosphere and vaporized.
As a result, as shown in FIG. 2, in winter, in addition to normal operation in which cold water is stored in the cold water well 12 at the same time as heating in the heat load LD, supplementary operation to the cold water well 12 using the cooling tower 207 is performed as necessary. Cool storage becomes possible.

The solar heat collector 202 heats the medium of the heat storage auxiliary equipment 20 using solar heat obtained by heating water by the sun.
As a result, as shown in FIG. 2, in summer, in addition to the normal operation in which heat is stored in the hot water well 11 at the same time as cooling in the heat load LD, the hot water well 11 is stored in the hot water well 11 using the solar heat collector 202 as necessary. auxiliary heat storage becomes possible.

(Configuration of control device)
As shown in FIG. 3, the control device 50 functionally includes a material balance control section 501 and a thermal balance control section 505.

The control device 50 includes a CPU 51, a memory 52, a communication interface 53, and a recording medium 54 as a hardware configuration.

The CPU 51 is a processor that performs various functions by operating according to programs prepared in advance. The functions of the CPU 51 will be described later.

The memory 52 has a storage area necessary for the operation of the CPU 51.

The communication interface 53 is a connection interface for communicably connecting to other devices via a communication line, and is configured to be able to send commands to other devices and receive responses from other devices. has been done.

The recording medium 54 is a local recording medium provided within the housing of the control device 50, and is a large-capacity storage device such as an HDD or an SSD.

Next, the functions of the CPU 51 of the control device 50 will be explained.
The CPU 51 functions as the material balance control section 501 and the thermal balance control section 505, as described above, by operating according to a program prepared in advance.

(Configuration of material balance control section)
The material balance control unit 501 controls the heat source well equipment 10 so that the annual volume of pumped water and the volume of returned water of each of the hot water well 11 and the cold water well 12 are made equal.
The material balance control section 501 includes a volume calculation section 502 and a well equipment operation section 503.

The volume calculation unit 502 calculates the set volume of water to be pumped or returned from each well in each operating period of the year.
Specifically, the volume calculation unit 502 calculates the set volumes for the hot water well 11 and the cold water well 12 separately during the heating operation period (for example, one period in winter).
Further, the volume calculation unit 502 calculates the set volumes for the hot water well 11 and the cold water well 12 separately during an operation period in which heating and low-temperature outside air are used together (for example, another period in winter).
Further, the volume calculation unit 502 calculates the set volumes for the hot water well 11 and the cold water well 12 separately during the cooling operation period (for example, in the summer).

The well equipment operation unit 503 operates the heat source well equipment 10 based on the calculated set volume.
Specifically, a command is sent to the pump PP, the regulating valve RV, etc., and the flow rate of water in the pipe 13 is adjusted so that the volume of water pumped or returned from each well during each operation period becomes the calculated set volume. Control.

(Configuration of thermal balance control section)
The heat balance control unit 505 controls the heat storage auxiliary equipment 20 so that the annual heat amount of pumped water and the heat amount of returned water of both the hot water well 11 and the cold water well 12 are made equal.
Thermal balance control section 505 includes a temperature calculation section 506 and an auxiliary equipment operation section 509.

The temperature calculation unit 506 calculates the temperature of the return water to be returned.
Specifically, the temperature calculation unit 506 calculates the temperature of return water to the cold water well 12 during a heating operation period (for example, one period in winter).
Furthermore, the temperature calculation unit 506 calculates the temperature of return water to the cold water well 12 during a period of combined operation of heating and low-temperature outside air (for example, another period in winter).
Furthermore, the temperature calculation unit 506 calculates the temperature of water returned to the hot water well 11 during the cooling operation period (for example, during another period in the summer).

The temperature calculation section 506 includes a first calculation section 507 and a second calculation section 508.
The first calculation unit 507 calculates a weighted average value of the pumped water temperature response using a model equation that calculates the pumped water temperature response from the previous period's return water history. Details of the model formula will be described later.
The second calculation unit 508 determines the next return water temperature from the pumped water temperature response calculated by the first calculation unit 507.

The auxiliary equipment operating unit 509 operates the heat storage auxiliary equipment 20 based on the temperature of the return water calculated by the temperature calculation unit 506 to be returned.
Specifically, when heating is required in each operation period, the auxiliary equipment operation unit 509 returns water at the volume calculated by the volume calculation unit 502 while returning the water to the calculated return water temperature. , sends a command to the heating device 201 of the heat storage auxiliary equipment 20, and operates the heating capacity of the heating device 201.
Conversely, when cooling is required during each operation period, the auxiliary equipment operation section 509 returns water with the volume calculated by the volume calculation section 502 and stores heat so that the return water temperature becomes the calculated return water temperature. A command is sent to the cooling device 206 of the auxiliary equipment 20 to manipulate the cooling capacity of the cooling device 206.

(Operation of control device)
The operation of the control device 50 of this embodiment will be explained.
The operation of the control device 50 corresponds to an embodiment of the control method.
The control device 50 implements each step shown in FIG.

First, the material balance control unit 501 controls the heat source well equipment 10 so that the annual pumped water volume and the returned water volume of each of the hot water well 11 and the cold water well 12 are equalized (ST01: material balance control step).
Specifically, the volume calculation unit 502 calculates the set volume to be pumped or returned in each operating period of the year (ST01A: set volume calculation step), and the well equipment operation unit 503 operates the heat source well equipment 10. (ST01B: Well equipment operation step)

In parallel with the implementation of ST01, the heat balance control unit 505 controls the heat storage auxiliary equipment 20 to equalize the annual heat amount of pumped water and the heat amount of returned water for both the hot water well 11 and the cold water well 12 (ST02 : material equilibrium control step).
Specifically, the temperature calculation unit 506 calculates the set temperature at which water should be returned during each operating period of the year (ST02A: set temperature calculation step), and the auxiliary equipment operation unit 509 operates the heat storage auxiliary equipment based on the set temperature. 20 (ST02B: auxiliary equipment operation step).

(Detailed explanation of model formula)
In the geothermal heat utilization system 1, a model as shown in FIG. 5 is constructed.
In FIG. 5, the vertical axis shows the pumped water/return water temperature, and the horizontal axis shows the pumped water/return water volume.
The geothermal heat utilization system 1 can set the return water temperature, and it is kept constant during the heat storage/cold storage period in FIG. 5 as well.
The model shown in FIG. 5 assumes that the summer cooling load is larger than the winter heating load. For this reason, the model shown in FIG. 5 includes operation of the heat storage auxiliary equipment 20 in winter in order to compensate for the amount of cold energy that is insufficient to store cold heat through heating operation. If the summer cooling load is greater than the winter heating load, it will be necessary to operate to supplement heat storage in the summer.
Since the pumped water temperature is affected by the previous year's return water history, a model formula is created to calculate the pumped water temperature response from the previous year's return water history, and the water injection temperature for the next year's operation is determined.
The pumped water temperature gradually decreases or increases toward the initial groundwater temperature during the pumping period, but in the created simple model, the pumped water temperature response is calculated and used as a weighted average value of the returned water.

Here, regarding the definition of positive and negative amounts of heat, the inflow of heat into the aquifer LY is defined as positive, and the outflow of heat from the aquifer LY is defined as negative.
In addition, each symbol is defined as follows.
Qw,w: Heat amount in winter (area of the shaded part shown in Figure 5)
Qw,s: Summer heat amount (shaded area shown in Figure 5)
Tp,w: Hot water well pumping temperature in winter Ti,w,1: Cold water well return temperature in winter Ti,s: Hot water well return temperature in summer Tp,s: Cold water well pumping temperature in summer Ti,w,2: Average return water temperature during the combined operation period of heating and low-temperature outside air Vw,1: Pumped water/return water volume during the heating operation period Vw,2: Pumped water/return water volume during the combined operation period of heating and low-temperature outside air Vw,s: Volume of pumped and returned water during cooling operation period Vw,w = Vw,1 + Vw,2

The amount of heat Qw,w (the area of the shaded part shown in FIG. 5) in winter is expressed by equation (1).

The first term on the right side of equation (1) becomes equation (2).

Here, the average temperature of Tp,w during the heating operation period is set as shown in equation (3).

Then, equation (2) becomes equation (4).

Similarly, the average temperature of Tp,w during the combined operation period of heating and low-temperature outside air is set as shown in equation (5).

Then, equation (1) becomes equation (6).

Similarly, in equation (7), which is the amount of heat Qw,s in summer (the area of the shaded part shown in FIG. 5), equation (8) is set.

Then, equation (9) is obtained.

As a result, equations (6) and (9) are obtained as equations for the annual cycle.

Next, the material balance equation for the annual cycle is equation (10).

The heat balance equation for the annual cycle is equation (11).

From the above, heat-material balance control can be formulated as follows.
“In the annual cycle, variables Ti,w,1, Ti,w,2, Ti,s, Vw,1, Vw that satisfy equations (6), (9), equations (10), and equations (11) ,2.”

In order to realize the annual heat-material balance control described above, a model is required to obtain the pumped water temperature response from the return water history.

Tp,w (warm water well pumping temperature in winter) is determined from Ti,s (warm water well return water temperature in summer) by the function shown in equation (12).

Tp,s (cold water well pumping temperature in summer) is determined by Ti,w,1 (cold water well return water temperature in winter) and Ti,w,2 (average return water temperature during combined operation period of heating and low temperature outside air). , it is determined by the function shown in equation (13).

The heat recovery rate ε for each period is defined as the ratio of production energy to input energy when the same amount of water is injected into the aquifer LY and pumped from there. The energy content of water is defined with reference to the ambient temperature T0 of the aquifer LY. The heat recovery rate ε is expressed by equation (14).

Equation (14) can be written as Equation (15).

The dimensionless temperature T' is defined as in equation (16).

Equation (14) of the heat recovery rate can be expressed as Equation (17).

When the return water flow rate and the pumped water flow rate are constant, the dimensionless pumped water temperature is expressed by equation (18).

The pumped water temperature response for the first and second cycles cannot be predicted from past data, so it must be estimated using the following procedure.

[1] Set physical property values and aquifer conditions.

[2] From the longitudinal dispersion length and equivalent thermal conductivity, calculate the effective thermal conductivity according to equation (19).

[3] Calculate the dimensionless number as shown in equation (20).

[4] Pumped water temperature database (by Doughty et al., “A Dimensionless Parameter Approach to the Thermal Behavior of an Aquifer Thermal Energy Storage System”, WATER RESOURCES RESEARCH, June 1982, VOL.18, NO.3 , pp. 571-587), by Nakao and Nakanishi (Masayoshi Nakao, Kotone Nakanishi, et al., “Pumped water temperature prediction method for planning aquifer heat storage system (first report): non-dimensionalization approach and issues of past research” Extract pumped water temperature data that is close to a dimensionless number from the Society of Air Conditioning and Sanitary Engineers Conference Academic Conference Papers, Public Interest Incorporated Association, Society of Air Conditioning and Sanitary Engineers, 2020, Volume 2, p. 169-172)) .

(action and effect)
According to this embodiment, the control device 50 can equalize the volume of pumped water and the volume of returned water for each well in a year, and can equalize the amount of heat of pumped water and the amount of heat of returned water for both wells in a year.
Therefore, the control device 50 easily maintains the heat balance and volume balance throughout the year.
In addition, if these balances can be maintained throughout the year, the drop or rise in return water temperature can be suppressed, the size of the underground thermal mass can be stabilized, and the impact on surrounding aquifers and the global environment can be suppressed.
In addition, since it is easy to automatically control, stable operation over a long period of time is possible, making it easier to popularize the use of aquifer heat storage.
Furthermore, since the cold storage operation method, operation time, etc. can be determined in advance, it is possible to reduce heat storage, power consumption loss, etc.
Furthermore, by simply determining the average pumped water temperature change, the control device 50 can easily perform material balance control and heat balance control.

Further, the control device 50 of the present embodiment calculates the set volume to be pumped or returned and the set temperature to return water in each operating period of the year, and operates the heat source well equipment 10 and the heat storage auxiliary equipment 20. , the control device 50 can set the heat source well equipment 10 and the heat storage auxiliary equipment 20 to the volume to be pumped or returned and the temperature to be returned, which are the targets for each operation period.

Further, by including the first calculation unit 507, the control device 50 of this embodiment can predict the average return water temperature in a period including whether or not the heat storage auxiliary equipment 20 is used.

Moreover, the control device 50 of this embodiment can predict the next return water temperature by including the second calculation unit 508.

Moreover, the heating device 201 of this embodiment includes the solar heat collector 202, so that it is possible to use unused natural energy such as solar heat.

Moreover, the cooling device 206 of this embodiment includes the cooling tower 207, so that it is possible to store cold by utilizing the low outside temperature.

Moreover, in this embodiment, since heat exchange is performed between the water in the piping 13 and the medium on the heat pump 30 side and the heat storage auxiliary equipment 20 side, the heat source well equipment 10 and the heat load LD and the heat source well Heat can be easily absorbed between the equipment 10 and the heat storage auxiliary equipment 20.

<Modified example>
In this embodiment, the heat storage auxiliary equipment 20 includes a heating device 201 and a cooling device 206, but it may be configured in any manner as long as it can assist in heat storage.
As a modification, in a cold region, the heat storage auxiliary equipment 20 may include only the heating device 201 out of the heating device 201 and the cooling device 206.
As another modification, in a warm region, the auxiliary heat storage equipment 20 may include only the cooling device 206 out of the heating device 201 and the cooling device 206.

In this embodiment, the temperature calculation unit 506 includes a first calculation unit 507 and a second calculation unit 508, but may be configured in any manner as long as it can calculate the return water temperature.
As a modification, the temperature calculation unit 506 may include only the first calculation unit 507 out of the first calculation unit 507 and the second calculation unit 508.
As another modification, the temperature calculation unit 506 may include only the second calculation unit 508 out of the first calculation unit 507 and the second calculation unit 508.

Although the heat pump 30 is provided for the heat load LD, it may also be provided for other equipment if necessary to provide hot or cold heat to the water in the pipe 13.
As a modification, the heat pump 30 may be provided for the heat storage auxiliary equipment 20 in addition to the heat load LD.

In each of the embodiments described above, a program for realizing various functions of the control device 50 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. Various processes are performed by setting and executing the command. Here, various processes of the CPU 51 of the computer system are stored in a computer-readable recording medium in the form of a program, and the various processes described above are performed by reading and executing this program by the computer. Further, the computer-readable recording medium refers to a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, and the like. Alternatively, this computer program may be distributed to a computer via a communication line, and the computer receiving the distribution may execute the program.

<Other embodiments>
Although the embodiment of the present disclosure has been described above, this embodiment is shown as an example and is not intended to limit the scope of the present disclosure. This embodiment can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the present disclosure. This embodiment and its modifications are included within the scope and gist of the present disclosure, as well as within the scope of the present disclosure and its equivalents.

<Additional notes>
The control device 50, geothermal heat utilization system 1, control method, and program described in the above-described embodiment can be understood, for example, as follows.

(1) The control device 50 according to the first aspect controls the heat source well equipment 10 including the hot water well 11 and the cold water well 12 to determine the annual pumped volume and return water of each of the hot water well 11 and the cold water well 12. A heat storage auxiliary equipment 20 including at least one of a heating device 201 and a cooling device 206 is connected to a material balance control unit 501 that controls the volumes to be equal to each other, and a heat storage auxiliary equipment 20 that includes at least one of a heating device 201 and a cooling device 206. A heat balance control unit 505 is provided that controls the heat amount of pumped water and the heat amount of returned water in the year to be equal.

According to this aspect, the control device 50 can equalize the pumped water volume and return water volume of each well in a year, and can make the pumped water heat amount and return water heat amount of both wells equal in a year.
Therefore, the control device 50 easily maintains the heat balance and volume balance throughout the year.
In addition, if these balances can be maintained throughout the year, the drop or rise in return water temperature can be suppressed, the size of the underground thermal mass can be stabilized, and the impact on surrounding aquifers and the global environment can be suppressed.
In addition, since it is easy to automatically control, stable operation over a long period of time is possible, making it easier to popularize the use of aquifer heat storage.
Furthermore, since the cold storage operation method, operation time, etc. can be determined in advance, it is possible to reduce heat storage, power consumption loss, etc.

(2) In the control device 50 according to the second aspect, the material balance control unit 501 includes a volume calculation unit 502 that calculates a set volume of water to be pumped or returned in each operating period of the year, and the heat balance control unit 50 The unit 505 includes a temperature calculation unit 506 that calculates a set temperature at which water should be returned in each of the operating periods, a well equipment operation unit 503 that operates the heat source well equipment 10 based on the set volume, and a well equipment operation unit 503 that operates the heat source well equipment 10 based on the set volume. Based on the above, the control device 50 of (1) further includes an auxiliary equipment operating section 509 that operates the heat storage auxiliary equipment 20.

According to this aspect, the control device 50 can set the heat source well equipment 10 and the heat storage auxiliary equipment 20 to the volume to be pumped or returned and the temperature to be returned, which are the targets for each operation period.

(3) In the control device 50 according to the third aspect, the temperature calculation unit 506 calculates a weighted average value of the pumped water temperature response using a model formula for calculating the pumped water temperature response from the previous period's return water history. This is the control device 50 of (2) including a calculation unit 507.

According to this aspect, the control device 50 can predict the average return water temperature in a period including whether or not the heat storage auxiliary equipment 20 is used.

(4) In the control device 50 according to the fourth aspect, the temperature calculation unit 506 includes a second calculation unit 508 that calculates the next return water temperature from the pumped water temperature response calculated by the first calculation unit ( This is the control device 50 of 2) or (3).

According to this aspect, the control device 50 can predict the next return water temperature.

(5) The control device 50 according to the fifth aspect is the control device 50 according to any one of (1) to (4), in which the heating device 201 includes a solar heat collector 202.

According to this aspect, unused natural energy such as solar heat can be used.

(6) The control device 50 according to the sixth aspect is the control device 50 according to any one of (1) to (5), in which the cooling device 206 includes a cooling tower 207.

According to this aspect, cold storage using low outside temperature is possible.

(7) In the control device 50 according to the seventh aspect, the heat source well equipment 10 further includes a pipe 13 connecting the hot water well 11 and the cold water well 12, and between the heat load LD and the inside of the pipe 13. (1) The heat exchanger 40 performs heat exchange between the water in the piping 13 and the medium on the heat pump 30 side and the heat storage auxiliary equipment 20 side. The control device 50 is any one of (6) to (6).

According to this aspect, since heat exchange is performed between the water in the pipe 13 and the medium on the heat pump 30 side and the heat storage auxiliary equipment 20 side, the heat source well equipment 10 and the heat load LD and the heat source well equipment Heat can be easily absorbed between 10 and the heat storage auxiliary equipment 20.

(8) The geothermal heat utilization system 1 according to the eighth aspect includes the control device 50 of any one of (1) to (7), the heat source well equipment 10, and the heat storage auxiliary equipment 20. .

According to this aspect, the geothermal heat utilization system 1 can equalize the annual pumped water volume and the returned water volume of each well, and can make the annual pumped water heat amount and the returned water heat amount of both wells equal.
Therefore, the geothermal heat utilization system 1 can easily maintain the heat balance and volume balance throughout the year.
In addition, if these balances can be maintained throughout the year, the drop or rise in return water temperature can be suppressed, the size of the underground thermal mass can be stabilized, and the impact on surrounding aquifers and the global environment can be suppressed.
In addition, since it is easy to automatically control, stable operation over a long period of time is possible, making it easier to popularize the use of aquifer heat storage.
Furthermore, since the cold storage operation method, operation time, etc. can be determined in advance, it is possible to reduce heat storage, power consumption loss, etc.

(9) In the control method according to the ninth aspect, the heat source well equipment 10 including the hot water well 11 and the cold water well 12 is configured to control the annual pumping volume and return water volume of each of the hot water well 11 and the cold water well 12. The heat storage auxiliary equipment 201 including at least one of the heating device 201 and the cooling device 206 is controlled to be equal to the amount of heat pumped in the year of both the hot water well 11 and the cold water well 12. The amount of water heat is controlled to be equal to the amount of water heat.

According to this aspect, the control method can make the pumped water volume and the return water volume of each well equal in a year, and can make the pumped water heat amount and the return water heat amount of both wells equal in a year.
Therefore, the control method makes it easy to maintain heat balance and volume balance throughout the year.
In addition, if these balances can be maintained throughout the year, the drop or rise in return water temperature can be suppressed, the size of the underground thermal mass can be stabilized, and the impact on surrounding aquifers and the global environment can be suppressed.
In addition, since it is easy to automatically control, stable operation over a long period of time is possible, making it easier to popularize the use of aquifer heat storage.
Furthermore, since the cold storage operation method, operation time, etc. can be determined in advance, it is possible to reduce heat storage, power consumption loss, etc.

(10) The program according to the tenth aspect causes a computer to set a heat source well equipment including a hot water well and a cold water well, and to set the pumped water volume and return water volume of each well of the hot water well and the cold water well to be equal to each other in a year. The heat storage auxiliary equipment including at least one of the heating device and the cooling device is controlled so as to equalize the heat amount of pumped water and the heat amount of returned water in both the hot water well and the cold water well during the year. Make the thing you control do.

According to this aspect, the program can make the pumped water volume and return water volume of each well equal each year, and can make the pumped water heat amount and return water heat amount of both wells equal each year.
Therefore, the program tends to maintain caloric balance and volumetric balance throughout the year.
In addition, if these balances can be maintained throughout the year, the drop or rise in return water temperature can be suppressed, the size of the underground thermal mass can be stabilized, and the impact on surrounding aquifers and the global environment can be suppressed.
In addition, since it is easy to automatically control, stable operation over a long period of time is possible, making it easier to popularize the use of aquifer heat storage.
Furthermore, since the cold storage operation method, operation time, etc. can be determined in advance, it is possible to reduce heat storage, power consumption loss, etc.

1 Geothermal heat utilization system 11 Hot water well 12 Cold water well 13 Piping 20 Heat storage auxiliary device 30 Heat pump 40 Heat exchanger 50 Control device 51 CPU
52 Memory 53 Communication interface 54 Recording medium 131 First end 132 Second end 201 Heating device 202 Solar heat collector 206 Cooling device 207 Cooling tower 501 Material balance control section 502 Volume calculation section 503 Well equipment operation section 505 Heat balance control section 506 Temperature Calculation unit 507 First calculation unit 508 Second calculation unit 509 Auxiliary equipment operation unit CV Check valve LD Heat load LY Aquifer PP Pump RV Adjustment valve

Claims (10)

a material balance control unit that controls a heat source well facility including a hot water well and a cold water well so that the pumped water volume and the returned water volume of each of the hot water well and the cold water well are equal to each other in a year;
a heat balance control unit that controls a heat storage auxiliary equipment including at least one of a heating device and a cooling device so as to equalize the heat amount of pumped water and the heat amount of returned water in both the hot water well and the cold water well in the year; ,
A control device comprising: The material balance control unit includes a volume calculation unit that calculates a set volume of water to be pumped or returned in each operating period of the year,
The heat balance control unit includes a temperature calculation unit that calculates a set temperature at which the water should be returned in each of the operation periods,
a well equipment operation unit that operates the heat source well equipment based on the set volume;
an auxiliary equipment operation unit that operates the heat storage auxiliary equipment based on the set temperature;
The control device according to claim 1, further comprising:. 3. The control device according to claim 2, wherein the temperature calculation section includes a first calculation section that calculates a weighted average value of the pumped water temperature response using a model equation that calculates the pumped water temperature response from the previous period's return water history. The control device according to claim 3, wherein the temperature calculation unit includes a second calculation unit that calculates the next return water temperature from the pumped water temperature response calculated by the first calculation unit. The control device according to any one of claims 1 to 4, wherein the heating device includes a solar heat collector. The control device according to any one of claims 1 to 5, wherein the cooling device includes a cooling tower. The heat source well equipment further includes piping connecting the hot water well and the cold water well,
a heat pump provided between the heat load and the inside of the piping;
a heat exchanger that exchanges heat between the water in the piping and the medium on the heat pump side and the heat storage auxiliary equipment side;
The control device according to any one of claims 1 to 6, further comprising: A control device according to any one of claims 1 to 7,
The heat source well equipment;
The heat storage auxiliary equipment;
A geothermal heat utilization system. Controlling a heat source well equipment including a hot water well and a cold water well so that the annual pumped water volume and the returned water volume of each of the hot water well and the cold water well are equal,
Controlling a heat storage auxiliary equipment including at least one of a heating device and a cooling device so as to equalize the heat amount of pumped water and the heat amount of returned water in the year of both the hot water well and the cold water well.
Control method. to the computer,
Controlling a heat source well equipment including a hot water well and a cold water well so that the annual pumped water volume and the returned water volume of each of the hot water well and the cold water well are equal,
Controlling a heat storage auxiliary equipment including at least one of a heating device and a cooling device so as to equalize the heat amount of pumped water and the heat amount of returned water in both the hot water well and the cold water well during the year. program.

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