JPH08184063A - Underground heat storage device - Google Patents

Abstract

PURPOSE: To reduce costs by a method wherein when a building is constructed, a hollow foundation pile is driven into the ground and at the same time heating medium is injected into the foundation pile using a heating medium injecting, extracting means or the heating medium is extracted from within the foundation pile. CONSTITUTION: Heating medium is injected from an air conditioner 6 into the hollow section 5 of a foundation pile 4 through a heating medium pipe 7a, while the heating medium is extracted from within the section 5 through a heating medium pipe 7b. Next, at this moment, heat of the heating medium stored in the section 5 is stored in the soil of great volume in the underground through all seasons for a long period of time. And as heating medium, air or other gas, or water or other liquid is used. And, if required, inner pipes, partition walls, or heat transfer tubes are inserted into the section 5 to form a heating medium passage. Further a means for accelerating heat transfer between heating medium, inner and outer walls of pile, underground, a heat collecting circuit, a temperature measuring unit, a flow regulating unit are provided. Thus, embedding of heat transfer tubes is not needed and heat can be stored for a long period of time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underground heat storage device,
More specifically, the present invention relates to an underground heat storage device capable of storing low temperature heat of about atmospheric temperature for a long period of several months.

[0002]

2. Description of the Related Art As a heat storage device for storing heat for cooling and heating,
Although water heat storage tanks or ice heat storage tanks have been put into practical use, such artificially built heat storage tanks can only withstand heat storage for several days from the viewpoint of heat insulation. From an ideal energy saving point of view, the heat should be able to be stored for a long period of time for months, so that high temperatures in summer can be used for heating in winter and low temperatures in winter can be used for heating in summer. .

Such heat storage for several months can theoretically be realized by utilizing the reaction heat of a chemical substance, but this chemical heat storage is far from practical use in terms of cost.

Under these circumstances, various researches have been conducted on an underground heat storage device which stores heat in the ground by utilizing the heat capacity and heat insulating property of soil. For example, in "Heat Storage / Heat Increasing Technology" (November 1985, issued by PC Corporation) edited by the Heat Storage / Heating Technology Editing Committee, JP-A-5-118701, or JP-A-5-118702. , An underground heat storage device is disclosed.

FIGS. 18A and 18B show the structure of a conventional underground heat storage device. A heat transfer tube 2 of a heat exchanger is embedded in the ground 1 below the building 3. A fluid flows in or out of the heat transfer tube 2, and heat is injected into or extracted from the ground 1 via the heat transfer tube 2. As a result, the heat demand of the building 3 is covered.

As for the structure of the heat transfer tube 2, as shown in FIG. 18 (a), the heat transfer tube 2 extends vertically into the ground 1, and FIG.
As shown in FIG. 8 (b), there are some that extend horizontally in the ground 1. Further, as a specific structure of the vertical type heat transfer tube 2 of FIG. 18A, a zigzag shape as shown in FIG. 18A and a U-shaped tube structure as shown in FIG. Some of them have a double pipe structure as shown in FIG. 19B, and there are various other ones although not shown.

[0007]

As described above, various researches and developments have been carried out on the underground heat storage device, but the heat transfer tubes of the heat exchanger must be buried deep in the ground, which causes a rise in cost. However, it was said that practical application is relatively difficult.

That is, since the thermal conductivity of the soil itself can be said to be a poor conductor of heat, the heat transfer tube of the heat exchanger having a large heat transfer area can be used for sending heat into the ground and extracting heat. Need to be buried over a wide area in the ground. Therefore, the amount of heat transfer tubes in the heat exchanger will be enormous and the construction cost for burying these heat transfer tubes deep in the ground will rise, so even if the heat storage material and the heat insulating material are provided free of charge. It was relatively difficult to put the underground heat storage device into practical use.

The object of the present invention was made in view of the above-mentioned circumstances, and the function as a heat exchanger is achieved in a foundation pile that is necessarily driven into the ground when a building is constructed. The purpose is to provide an underground heat storage device that is extremely inexpensive.

[0010]

In order to achieve this object, an underground heat storage apparatus according to the present invention stores heat in the ground by injecting a heat medium into the ground or extracting a heat medium from the ground. In the underground heat storage device to do, during the construction of a building, a hollow foundation pile driven into the ground and a heat medium is injected into the hollow of the foundation pile or the heat medium is injected from the inside of the foundation pile. And a heat medium injection and extraction means for performing extraction.

[0011]

As described above, according to the present invention, since the hollow foundation pile serves as a heat exchanger in the ground, it is not necessary to embed the heat transfer tube of the heat exchanger in the ground as in the conventional case. It is possible to store heat for a long period of several months, and it is possible to provide an extremely inexpensive large-scale underground heat storage device.

As a result, for example, a heat medium can be injected into the hollow of the foundation pile or extracted from the hollow. Therefore, in the summer, the heat is injected into the ground below the building and the heat is stored in the ground. . When winter comes, the heat medium in the ground can be extracted and used by extracting the heat medium from the inside of the hollow of the foundation pile. Since the underground temperature is lowered by the extraction of the underground heat, this low temperature can be used as cold heat in the summer before the heat storage.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An underground heat storage device according to embodiments of the present invention will be described below with reference to the drawings.

An underground heat storage device according to a first embodiment of the present invention will be described with reference to FIG. 1 (the first embodiment corresponds to claims 1 to 3).

As shown in FIG. 1, when the building 3 is constructed, a large number of underground 1 under the building 3 are provided except in a special case where the building is directly built on rock. The foundation piles 4 are driven in, and the building 3 is built on these foundation piles 4. The foundation pile 4 is a concrete hollow pipe having a hollow portion 5.

In this embodiment, the heat medium pipes 7a and 7b extended from the air conditioner 6 (heat medium injection / extraction means) are drawn into the hollow portion 5 of the foundation pile 4. As a result, the heat medium is injected from the air conditioner 6 into the hollow portion 5 of the foundation pile 4 via the one heat medium pipe 7a, and the foundation pile 4
The heat medium is extracted from the hollow portion 5 into the air conditioner 6 via the other heat medium pipe 7b. As a result, the heat medium stored in the hollow portion 5 of the foundation pile 4 stores heat by the huge soil in the ground, enabling long-term heat storage throughout the season.

The heat medium (fluid) flowing in the heat medium pipes 7a and 7b may be air or other gas, or may be water or other liquid.

When the heat medium is gas, the foundation pile 4 does not need to be watertight, and a conventional general-purpose foundation pile can be applied to this embodiment as it is. However, since the gas has a low density, it is necessary to make the heat medium pipes 7a and 7b relatively thick, and the amount of heat exchanged per unit time is small, but in the case of long-term heat storage such as seasonal heat storage, Since the heat is stored for a long time, the amount of heat exchanged per unit time does not matter so much.

When the heat medium is a liquid, the foundation pile 4 needs to be watertight, but the heat medium pipes 7a and 7b only need to be formed relatively thin, and the unit time A large amount of heat can be exchanged.

A heat storage device in which the hollow portion of the foundation pile is formed as a water tank to form a heat storage tank is disclosed in, for example, Japanese Patent Laid-Open No. 4-35663.
No. 6 and Japanese Patent Laid-Open No. 5-322234. However, in these publications, since the purpose is to store heat in the water in the hollow portion of the foundation pile, the amount of heat storage material (water) is also limited, so a heat storage water tank normally installed in the basement However, it is not suitable for long-term heat storage throughout the season and is different from the present embodiment.

Next, an underground heat storage device according to a second embodiment of the present invention will be described with reference to FIG. 2 (the second embodiment corresponds to claim 4).

As shown in FIG. 2, in this embodiment, the inner pipe 4a is inserted inside the foundation pile 4 to form a double pipe. Internal space 9 of this inner pipe 4a, foundation pile 4 and inner pipe 4a
The space 10 between and is communicated with the innermost portion 8 of the foundation pile 4. As a result, the heat medium flows in from one of the internal space 9 and the space 10 and flows out from the other. This flow direction may be always the same direction, and may be switched as needed. The inner pipe 4a and the foundation pile 4 may be concentric or may not be concentric.

Next, an underground heat storage device according to a third embodiment of the present invention will be described with reference to FIG. 3 (the third embodiment corresponds to claim 5).

As shown in FIG. 3, a partition wall 11 is provided in the foundation pile 4.
The inside of the foundation pile 4 is partitioned by inserting the
In the innermost part 8 of the partition wall 11, one side of the partition wall 11 communicates with the other side. The heat medium flows from one side of the partition wall 11 to the other side through the innermost portion 8.

Next, an underground heat storage device according to a fourth embodiment of the present invention will be described with reference to FIG. 4 (the fourth embodiment corresponds to claim 6).

As shown in FIG. 4, a U-shaped heat transfer tube 12 is inserted in the foundation pile 4, and a heat medium is introduced into and discharged from the heat transfer tube 12. In this case, the heat medium does not flow into or out of the hollow portion 5 of the foundation pile 4. In this embodiment, when the heat medium is a liquid,
There is an advantage that the foundation pile 4 does not have to be watertight. Further, the configuration of the heat transfer tube 12 is, as shown in the figure,
The shape of the heat transfer tube is not necessarily U-shaped and may be any other shape. Further, the heat transfer tube may be a smooth tube, a finned tube, or the like.

Next, an underground heat storage device according to a fifth embodiment of the present invention will be described with reference to FIG. 5 (the fifth embodiment corresponds to claim 7).

As shown in FIG. 5, a large number of protrusions 13 are formed on the inner wall of the foundation pile 4. This makes the foundation pile 4
The heat transfer between the heat medium flowing in the hollow portion 5 and the inner wall of the foundation pile 4 is promoted. The heat transfer promoting means may be fins, grooves, etc., in addition to the protrusions 13.

Next, an underground heat storage device according to a sixth embodiment of the present invention will be described with reference to FIG. 6 (the sixth embodiment corresponds to claim 8).

As shown in FIG. 6, a large number of fins 14 are formed on the outer wall of the foundation pile 4. This promotes heat transfer between the outer wall of the foundation pile 4 and the ground 1 around the foundation pile 4. As the heat transfer promoting means, a groove or the like may be used instead of the fin. Furthermore, the fifth embodiment and the sixth embodiment
The examples may be used together.

Next, with reference to FIG. 7, an underground heat storage apparatus according to a seventh embodiment of the present invention will be described (the seventh embodiment corresponds to claim 9).

Since the concrete foundation pile 4 has a low thermal conductivity of concrete, even if the heat transfer promoting means as shown in FIGS. 5 and 6 is provided, the foundation pile 4
Heat is relatively hard to transfer between the inner and outer walls of the. Seventh
The embodiment solves such a problem, and FIG.
As shown in FIG. 3, the wall of the foundation pile 4 is provided with a large number of heat transfer bodies 15 that penetrate the wall in the radial direction. This heat transfer body 1
5 is exposed to the inside and the outside from the inner wall and the outer wall of the foundation pile 4, respectively, and is formed of a material having a high thermal conductivity. The heat transfer body 15 improves heat transfer between the heat medium flowing in the hollow portion 5 of the foundation pile 4 and the ground around the foundation pile 4.

Protrusions, fins or the like may be provided at both ends of the heat transfer body 15 in order to improve thermal conductivity.

Next, an underground heat storage device according to an eighth embodiment of the present invention will be described with reference to FIG. 8 (the eighth embodiment corresponds to claim 10).

As shown in FIG. 8, a plurality of rooms 17 are formed in the foundation mat 16 of the building 3. Heat medium pipes 7 a, 7 b extending into the hollow portion 5 of the foundation pile 4 are inserted and arranged in these chambers 17. As a result, heat is exchanged with the room 17 by the heat medium flowing through the heat medium pipes 7a and 7b.

Next, with reference to FIG. 9, an underground heat storage device according to a ninth embodiment of the present invention will be described (the ninth embodiment corresponds to claim 11).

As shown in FIG. 9, a room 17 in the base mat 16 is divided by a partition wall 18 into a passage 19a on one side and a passage 19b on the other side. As a result, the passage 19
The heat medium flows from the air conditioner (not shown) into the hollow portion 5 of the foundation pile 4 through one of a and 19b, and the heat medium flows out from the hollow portion 5 of the foundation pile 4 into the air conditioner through the other passage. It This embodiment is applied when the heat medium is gas.

Next, referring to FIG. 10, the tenth aspect of the present invention will be described.
An underground heat storage device according to an embodiment will be described (the tenth embodiment corresponds to claim 12).

As shown in FIG. 10, in this embodiment, a solar heat collector 21 for collecting heat from solar heat, a heat exchanger 23 for exchanging heat with the river 22, and a heat load 20 are connected in parallel. The heat collecting circuit is configured. The heat collecting circuit and the hollow portion 5 of the foundation pile 4 are connected by heat transfer tubes 7a and 7b. As a result, the heat collected by the heat collecting circuit is stored in the foundation pile 4.

Since the temperature of the heat obtained by the solar heat collector 21 and the heat exchanger 23 depends on the weather or the climate, when the heat storage by the foundation pile 4 is used together, a part or the part of the fluctuating heat is changed. The parts can be supplemented.

Further, when the heat demand can be met only by the heat obtained by the solar heat collector 21 and the heat exchanger 23, the heat of the foundation pile 1 is stored as it is, and as a result, the heat storage time is increased. Is increased, and the heat utilization rate is improved.

Further, the heat source of the heat collecting circuit can be any one of solar heat, river heat, atmospheric air, seawater, sewage, factory waste heat and the like.

Further, in the illustrated example of FIG.
In contrast, the solar heat collector 21, the heat exchanger 23, the heat load 2
0 and the foundation pile 4 are connected in parallel, but these may be connected in series, and a method of appropriately switching between series and parallel, or a combination of series and parallel may be used. Good.

Next, referring to FIG. 11, the eleventh aspect of the present invention.
An underground heat storage device according to an embodiment will be described (the eleventh embodiment corresponds to claim 13).

As shown in FIG. 11, in this embodiment, a heat storage circuit is constructed by connecting a water heat storage tank 24 and an ice heat storage tank 25 in parallel to the heat load 20. In this heat storage circuit,
The hollow portion 5 of the foundation pile 4 is connected by heat transfer tubes 7a and 7b. As a result, it can be used in combination with any heat storage device that can handle the heat load 20.

Next, referring to FIG. 12, the twelfth aspect of the present invention will be described.
An underground heat storage device according to an embodiment will be described (the twelfth embodiment corresponds to claim 14).

As shown in FIG. 12, in this embodiment, the heat source 27 is connected in series with the heat pump 26, and the heat pump 26 is connected in series with the heat load 20. As a result, the heat of the heat source 27 is supplied to the heat load 20 with its temperature changed by the heat pump 26. In the heat pump 26, the hollow portion 5 of the foundation pile 4 is connected to the heat transfer pipe 7a,
It is connected by 7b. As a result, the heat stored in the foundation pile 4 is supplied to the heat load 20 with its temperature being changed by the heat pump 26 in a form of being used in combination with the heat source 27.

As described above, when the heat stored in the ground 1 is used as the heat source of the heat pump 26, the heat of the ground 1 is raised by the heat pump 26 and supplied to the heat load 20, for example, for heating demand. If so, the temperature of the underground 1 decreases with the extraction of heat, and eventually it does not function as a heat source. However, by that time, the season has changed, and now it is a time when cold heat for cooling is required, and the underground 1 whose temperature has dropped becomes to act as the cold heat source of the heat pump 26. When the cold heat of the underground 1 is lowered to the heat main p26 and supplied to the heat load 20 to be used for the demand such as cooling, the temperature of the underground 1 rises as the heat is extracted, and eventually functions as a cold heat source. Will not do. However, by that time, the season changes again, and a cycle in which cold heat for heating is required again can be configured, and an ideal heat storage device can be provided.

Next, referring to FIG. 13, the thirteenth aspect of the present invention will be described.
An underground heat storage device according to an embodiment will be described (a thirteenth embodiment corresponds to claim 15).

When heat is transferred to and from the ground 1 by a large number of foundation piles 1, control of the flow rate of the heat medium to each foundation pile 4 becomes a problem. In this case, as shown in FIG. 13, the foundation pile 4
It is easiest to handle all of the above in parallel. That is, the heat medium heat transfer tubes 7a, 7b extending from all the foundation piles 4
Are connected in parallel, and valves 28a and 28b are provided at locations where they are connected to the air conditioner 6. This valve 28a, 28
b controls the flow rate of the heat medium flowing through the heat medium heat transfer tubes 7a and 7b, whereby the heat injection amount between the underground 1 and
The amount of extraction is controlled. Such a system is easy to control and is suitable for a small-scale system having a small number of foundation piles 4.

Next, referring to FIG. 14, a fourteenth embodiment of the present invention will be described.
An underground heat storage device according to an embodiment will be described (a fourteenth embodiment corresponds to claim 16).

In the case of a large-scale system having a large number of foundation piles 4, as shown in FIG. 14, the foundation piles 4 are divided into a plurality of groups by a predetermined number, and valves 28a and 28b are provided for each group. There is. By controlling the opening of these valves 28a and 28b,
It is possible to control the amount of heat injection and the amount of heat extraction between and. The number of foundation piles 4 in each group does not have to be equal and may be divided for convenience of operation of the system. In such a case, it is possible to operate the system so that heat is injected in one part and heat is extracted in the other, and it is possible to meet the heat demand in a finely tuned manner, and the heat of the surrounding groups By starting the use from 1), the heat loss to the outside in the underground 1 can be reduced, and the heat utilization rate is also improved.

Next, referring to FIG. 15, the fifteenth aspect of the present invention
An underground heat storage device according to an embodiment will be described (a fifteenth embodiment corresponds to claim 17).

As shown in FIG. 15, the heat medium heat transfer tubes 7a and 7b extending from all the foundation piles 4 are connected in parallel, and the valves 28a and 28b are provided in the heat medium heat transfer tubes 7a and 7b. These valves 28a, 28b control the flow rates of the heat medium flowing through the heat medium heat transfer tubes 7a, 7b, respectively, and thereby control the heat injection amount / extraction amount with the underground 1.

Next, referring to FIG. 16, the 16th embodiment of the present invention
An underground heat storage device according to an embodiment will be described (a sixteenth embodiment corresponds to claims 18 to 21).

In a system that stores heat in the ground 1, if an attempt is made to operate with high efficiency, the temperature of the ground 1 subject to heat storage is not uniform, so it is necessary to measure the temperature distribution of the ground 1. Therefore, in this embodiment, as shown in FIG.
A temperature measuring device 31a is arranged in the foundation pile 4 and
Inside, a temperature measuring device 31b is arranged. Temperature measurement signals 32a from these temperature measurement devices 31a and 31b,
32 b is configured to be supplied to the analysis control device 29. Based on this result, the analysis control device 29 sends the control signals 30a and 30b to the flow rate control valves 28a and 28.
b, which causes the flow control valves 28a, 28b to
Is adjusted, the flow rate of the heat medium is manipulated, and the heat injection / extraction amount is controlled.

The temperature measuring devices 31a and 31b are provided both in the foundation pile 4 and in the ground 1, but either one may be provided. Moreover, the number of these temperature measuring devices can be freely selected as appropriate.

Next, referring to FIG. 17, the seventeenth aspect of the present invention
An underground heat storage device according to an embodiment will be described (the seventeenth embodiment corresponds to claim 22).

In the sixteenth embodiment, in order to measure the temperature in the foundation pile 4 or in the ground 1, temperature measuring devices 31a and 31b as shown in FIG. 16 may be installed, but the temperature measurement may be performed. Since the devices 31a and 31b can measure only the temperature of the installed position, in order to know the temperature distribution in the depth direction from near the surface to the deep part, the thermometer measurement devices 31a and 31b can be also measured in the depth direction. Must be placed in various places, and the construction of many of them is complicated.

Therefore, in this embodiment, as shown in FIG. 17, the optical fibers 33a and 33b are arranged along the path for measuring the temperature distribution in the foundation pile or the ground and are connected to the analysis control device 29. . As a result, when pulse light is sent from the analysis control device 29 to the optical fibers 33a and 33b, Raman scattered light is generated in the optical fibers 33a and 33b and returns to the analysis control device 29. Since there is a correlation with the temperature, if the temporal change of the Raman scattered light after emitting the pulsed light is monitored, the temperature at that position can be detected from the intensity of the Raman scattered light and the return time.

As described above, in this embodiment, the temperature distribution in the depth direction can be measured steplessly only by pulling the optical fibers 33a and 33b into the foundation pile 4 and the underground 1, and therefore, the present invention can be realized. This is useful when it is desired to measure the temperature three-dimensionally over a wide range.

The present invention is not limited to the above-mentioned embodiments, and can be variously modified.

[0063]

As described above, according to the present invention, since the hollow foundation pile serves as a heat exchanger in the ground, it is possible to bury the heat transfer tube of the conventional heat exchanger in the ground. No longer needed,
It is possible to store heat for a long period of several months, and it is possible to provide an extremely inexpensive large-scale underground heat storage device.

[Brief description of drawings]

FIG. 1 is a sectional view of an underground heat storage device according to a first embodiment of the present invention.

FIG. 2A is a sectional view of an underground heat storage device according to a second embodiment of the present invention, and FIG. 2B is a sectional view taken along line bb of FIG.

FIG. 3A is a sectional view of an underground heat storage device according to a third embodiment of the present invention, and FIG. 3B is a sectional view taken along line bb of FIG.

FIG. 4A is a sectional view of an underground heat storage device according to a fourth embodiment of the present invention, and FIG. 4B is a sectional view taken along line bb of FIG.

5A is a sectional view of an underground heat storage device according to a fifth embodiment of the present invention, and FIG. 5B is a sectional view of a foundation pile shown in FIG.

FIG. 6A is a sectional view of an underground heat storage device according to a sixth embodiment of the present invention, and FIG. 6B is a sectional view of the foundation pile shown in FIG.

7A is a sectional view of an underground heat storage device according to a seventh embodiment of the present invention, and FIG. 7B is a sectional view of a foundation pile shown in FIG.

FIG. 8 is a sectional view of an underground heat storage device according to an eighth embodiment of the present invention.

FIG. 9 is a sectional view of an underground heat storage device according to a ninth embodiment of the present invention.

FIG. 10 is a sectional view of an underground heat storage device according to a tenth embodiment of the present invention.

FIG. 11 is a sectional view of an underground heat storage device according to an eleventh embodiment of the present invention.

FIG. 12 is a sectional view of an underground heat storage device according to a twelfth embodiment of the present invention.

FIG. 13 is a sectional view of an underground heat storage device according to a thirteenth embodiment of the present invention.

FIG. 14 is a sectional view of an underground heat storage device according to a fourteenth embodiment of the present invention.

FIG. 15 is a sectional view of an underground heat storage device according to a fifteenth embodiment of the present invention.

FIG. 16 is a sectional view of an underground heat storage device according to a sixteenth embodiment of the present invention.

FIG. 17 is a sectional view of an underground heat storage device according to a seventeenth embodiment of the present invention.

18 (a) and 18 (b) are cross-sectional views of a conventional underground heat storage device, respectively.

19 (a) and 19 (b) are side views of a heat transfer tube of a conventional underground heat storage device, respectively.

[Explanation of symbols]

 1 Underground 3 Building 4 Foundation pile 5 Hollow part 6 Air conditioner (heat medium injection and extraction means) 11 Partition wall

Claims (22)

[Claims] 1. An underground heat storage device for injecting a heat medium into the ground or extracting a heat medium from the ground to store heat in the ground, which is driven into the ground during construction of a building. The underground heat storage device, comprising: a hollow foundation pile and a heat medium injection / extraction means for injecting the heat medium into the hollow of the foundation pile or extracting the heat medium from the inside of the hollow of the foundation pile. . 2. The underground heat storage device according to claim 1, wherein the heat medium is a gas. 3. The underground heat storage device according to claim 1, wherein the heat medium is a liquid. 4. An inner pipe is inserted in the hollow of the foundation pile, and an internal space in the inner pipe and a space between the inner pipe and the foundation pile are connected so as to allow a heat medium to flow therethrough. The underground heat storage device according to any one of claims 1 to 3, wherein 5. A partition is inserted into the hollow of the foundation pile to divide the inside of the foundation pile into one side and the other side, and one side and the other side of the foundation pile communicate with each other. The underground heat storage device according to any one of claims 1 to 3, wherein: 6. The underground heat storage device according to claim 1, wherein a heat transfer tube for circulating a heat medium inside is inserted in the hollow of the foundation pile. 7. The inner wall of the foundation pile is provided with heat transfer promoting means for promoting heat transfer between the heat medium flowing in the hollow of the foundation pile and the inner wall of the foundation pile. 6. The underground heat storage device according to any one of 5 to 5. 8. The ground according to claim 1, wherein the outer wall of the foundation pile is provided with heat transfer promoting means for promoting heat transfer between the outer wall and the ground. Medium heat storage device. 9. The wall of the foundation pile is provided with heat transfer bodies exposed inside and outside from the inner wall and the outer wall of the foundation pile, respectively, and the thermal conductivity of the heat transfer body is higher than that of the foundation pile. The underground heat storage device according to any one of claims 1 to 8, which is large. 10. The underground heat storage according to claim 1, wherein a heat medium heat transfer tube extending from the inside of the hollow of the foundation pile is arranged in the room of the foundation mat of the building. apparatus. 11. A room for a foundation mat of a building is divided into two passages by a partition wall, and these passages are connected to the inside of the foundation pile and the heat medium injection / extraction means. The underground heat storage device according to claim 1. 12. The heat medium heat transfer pipe extending from the inside of the hollow of the foundation pile is connected to a heat collecting circuit in which a heat collecting source and a heat load are connected to each other. Medium heat storage device. 13. The underground heat storage device according to claim 1, wherein a heat medium heat transfer pipe extending from the inside of the hollow of the foundation pile is connected to another heat storage device. 14. The underground heat storage device according to claim 1, wherein a heat medium heat transfer pipe extending from the inside of the hollow of the foundation pile is connected to the heat pump. 15. The underground heat storage device according to claim 1, wherein a plurality of heat medium heat transfer tubes extending from the insides of the plurality of foundation piles are connected in parallel. 16. The underground according to claim 1, wherein a plurality of foundation piles are divided into a plurality of groups, and heat medium heat transfer tubes extending from each group are connected in parallel. Heat storage device. 17. A plurality of heat medium heat transfer tubes extending in the hollow of a plurality of foundation piles are connected in parallel, and a flow control valve is provided in each heat medium heat transfer tube. Item 15. The underground heat storage device according to items 1 to 14. 18. A temperature measuring device for measuring a temperature distribution in the ground, and a control device for adjusting a flow rate of the heat medium heat transfer tube based on a temperature measuring signal from the temperature measuring device. The underground heat storage device according to claim 15, wherein the heat storage device is underground. 19. The underground heat storage device according to claim 15, wherein the temperature measuring device is arranged in the foundation pile. 20. The temperature measuring device is arranged in the ground around the foundation pile.
The underground heat storage device according to any one of 18 to 18. 21. The underground heat storage device according to claim 15, wherein the temperature measuring device is composed of at least two units arranged in the foundation pile and in the ground. 22. The underground heat storage device according to claim 19, wherein the temperature measuring device comprises an optical fiber extending into the foundation pile or into the ground around the foundation pile.