Method for installing geothermal facility and geothermal facility

Abstract

A method of installing a geothermal facility within a geological formation, comprising the steps of:-operating a geothermal well system comprising an inlet conduit, an outlet conduit and an interconnection conduit in fluid communication with the inlet conduit and interconnecting the inlet conduit with the outlet conduit; drilling an additional interconnected pipe by means of at least one service pipe; -interconnecting an additional interconnection conduit with the inlet conduit and the outlet conduit to fluidly communicate the inlet conduit with the outlet conduit through the additional interconnection conduit when the geothermal well system is not in operation; and-fluidly blocking the connection between the additional interconnection conduit and the service conduit using a blocking element. In addition, the invention further provides a geothermal facility.

Description

[0001] Identities of the Parties Involved

[0002] The applicant in this intellectual property case is Eaposys SA of Biel, Switzerland. The inventors of the invention described in this patent document are Lucien Vollmeroz of Fuessen, Switzerland, Naomi Vollmeroz of Annemasse, Switzerland, Alain Jacquard of Sainte-Croix, Switzerland, Marcel Thomas Knebel of Hoogeveen, the Netherlands, Arturs Blinovs of Hoogeveen, the Netherlands, and Gerardus Godfriedus Johannes van Ooijen of Hoogeveen, the Netherlands.

[0003] Copyright and Legal Notice

[0004] Portions of this patent document contain copyrighted material. The applicant does not object to anyone making a facsimile reproduction of the patent document or the patent disclosure as it appears in the patent file or records of the Patent and Trademark Office, but reserves all copyright rights in other respects. In addition, any reference in this document to a third party's patent or article should not be construed as an admission that the present invention is not entitled to antedate such material by virtue of a prior invented application. Technical Field

[0005] The present invention relates to geothermal installations and methods of installing geothermal installations. Background Art

[0006] Geothermal energy is a form of thermal energy that harnesses the natural heat of the earth. Geothermal energy is a renewable energy source and is not an intermittent energy source like solar or wind energy, which rely on sunlight or wind to generate electricity. There is a growing demand for dispatchable renewable energy and energy storage solutions. There is a continuous search for methods and devices for the production of dispatchable, reliable renewable energy.

[0007] Traditional geothermal (hydrothermal) resources require three main factors: 1) a sufficiently high underground temperature; 2) the presence of a geological formation or structure rich in high-temperature fluids; and 3) a sufficiently high thermal conductivity of the rock to ensure the required production and reinjection rates of geothermal brine. To achieve geothermal power generation (i.e., using dry heat resources) in places lacking hydrothermal resources, cold fluid needs to be injected into pre-fractured hot rock to provide a large heat exchange area. This is called an enhanced geothermal system (EGS). The cold fluid penetrates the underground heat exchanger and extracts the heat stored in the solid rock mass. One or more production wells bring the heated fluid back to the surface (Hirschberg et al., 2015). Enhanced geothermal systems (EGS) have several disadvantages: 1) The surface for heat exchange generated by hydraulic reservoir stimulation (i.e., injecting fluid under high pressure to form an interconnected fracture network) is basically uncontrolled in terms of geometry and size, and does not necessarily ensure the optimal fluid flow rate required for industrial exploitation; 2) Hydraulic reservoir stimulation can induce earthquakes, and microseisms may develop into larger earthquakes, posing a danger to surface residents and ultimately limiting the sustainability of the facility.

[0008] Other disadvantages of hydraulic fracturing include the need for extremely high pressures to break underground rocks, so most of the liquid injected into the bedrock for hydraulic fracturing penetrates too deep to be recovered.

[0009] Advances in geothermal energy collection technology have now spawned the concept of a closed-loop system, in which the heat transfer fluid circulates in a series of tunnels with very little leakage, avoiding the disadvantages of the EGS system.

[0010] Different prior arts disclose that geothermal facilities need to be shut down during expansion. However, expansion work requires heat energy. Therefore, the object of the present invention is to provide a more efficient method for installing geothermal facilities. Summary of the Invention

[0011] This task is achieved by a method for installing a geothermal facility in a geological formation, the method comprising the following steps:

[0012] - Operating a geothermal well system, the geothermal well system comprising an inlet pipe, an outlet pipe, and an interconnecting pipe, the interconnecting pipe being in fluid communication with the inlet pipe and interconnecting the inlet pipe and the outlet pipe;

[0013] - Drilling an additional interconnecting pipe by means of at least one service pipe;

[0014] - When the geothermal well system is not operating, interconnecting the additional interconnecting pipe with the inlet pipe and the outlet pipe to fluidly connect the inlet pipe and the outlet pipe through the additional interconnecting pipe; and

[0015] - Using a blocking element to fluidly block the connection between the additional interconnecting pipe and the service pipe.

[0016] The task is also achieved by a geothermal installation within a geological formation, the geothermal installation comprising an inlet pipe, an outlet pipe, a service pipe and two interconnecting pipes, the interconnecting pipes being in fluid communication with the inlet pipe and interconnecting the inlet pipe and the outlet pipe respectively, characterized in that a first interconnecting pipe is fluidically isolated from the service pipe by a blocking element, the blocking element being arranged in a pipe interconnecting the first interconnecting pipe and the service pipe.

[0017] Unless otherwise stated, the pipes according to the present application can be understood as wellbores.

[0018] An existing geothermal well system within a geological formation, which is preferably a closed-loop system, comprises an inlet pipe, an outlet pipe and at least one interconnecting pipe. The directions of the inlet pipe and the outlet pipe are preferably substantially vertical.

[0019] The direction of the interconnecting pipe is preferably horizontal. Thus, a heat transfer fluid (preferably a heat transfer liquid) flows downward in the inlet pipe into the geological formation, flows through at least one interconnecting pipe, and flows upward in the outlet pipe, mainly absorbing heat energy when flowing in the interconnecting pipe. In the present application, the (additional) interconnecting pipes can be understood as microtunnels. Depending on the technical requirements, these microtunnels may need to be cased or lined. The inlet pipe and the outlet pipe can be installed or arranged separately from each other.

[0020] It goes without saying that the pipes can be equipped with tubes or other suitable elements for the inflow of the heat transfer fluid. It is obvious that, within the interconnecting pipes, for example, the material of the interconnecting pipes (such as tubes) can be selected according to specific technical parameters. The interconnecting pipes can also be cased or lined to facilitate the circulation of the heat transfer fluid and the heat exchange between the heat transfer fluid and the surrounding geological formation. Such a blocking element can be a blocking valve, a cock, a stop valve or any other element capable of substantially closing the fluid connection between the additional interconnecting pipe and the service pipe to prevent fluid flow.

[0021] The existing geothermal well system can be expanded during the drilling of additional interconnecting pipes and the provision of the necessary technical elements for the interconnecting pipes. When drilling additional interconnecting pipes, at least one service pipe, such as a drill bit and its mechanical control equipment, is required. The operation of the existing geothermal well system only needs to be stopped (especially interrupted) when the additional interconnecting pipes are fluidically connected to the inlet pipe and the outlet pipe, and preferably when inserting a blocking element to fluidically disconnect the service pipe from the additional interconnecting pipe. Thus, the existing geothermal well system can operate for a long time during the installation of the geothermal installation. More precisely, the existing geothermal well system can operate at least during the drilling of the additional pipes.

[0022] During the operation of the geothermal facility, blocking elements are necessary to close the additional interconnecting pipes so that they are only fluidly connected to the inlet pipe and the outlet pipe. In other words, after installing at least one necessary blocking element to fluidly isolate the additional interconnecting pipes from the service pipes, the geothermal facility (including the geothermal well system and the additional interconnecting pipes) can operate. Preferably, if the service pipes are arranged in a straight line at least in several pipe sections, the blocking elements should be set or placed outside the straight pipe sections so as to still allow access from the service pipes to other interconnecting pipes located at a lower level for further construction or maintenance.

[0023] The service pipes are used for inserting, operating, and removing the drilling system, preferably a microtunnel drilling system. There is a section at the end of the drilling system that allows the drill bit of the drilling system to be directed to a predetermined direction; b) firmly fixing the drilling system within the service pipes; c) releasing the drilling system from this fixing device. The service pipes allow: a) the circulation of drilling mud without leakage to the ground, where the drilling mud comes from the drilling pipes; and b) at the end of drilling, introducing and fixing the blocking elements and connecting the blocking elements within the pipes (preferably within the service pipes) to keep the additional interconnecting pipes unobstructed so that the heat transfer fluid can flow within the additional interconnecting pipes. After emptying the additional interconnecting pipes and removing the drill bit, the blocking elements can be placed and positioned in their blocking positions, and when the blocking elements are in the blocking positions, the heat transfer fluid can hardly pass through the blocking elements. Before interconnecting the additional interconnecting pipes with the inlet pipe and / or the outlet pipe to fluidly connect to the inlet pipe, a beacon (radioactive or electromagnetic) source can be placed at the end of the drilled connecting pipe to facilitate connection to the inlet pipe or the outlet pipe respectively.

[0024] During operation, the heat transfer fluid circulates through the inlet pipe, the interconnecting pipes, and the outlet pipe and absorbs heat when flowing through these pipes, especially when flowing through the (one or more) interconnecting pipes of the geothermal facility within the formation or the geothermal well system respectively. If the original geothermal well system is a closed-loop system, the final geothermal facility is also a closed-loop system.

[0025] In a further improvement of the method for installing the geothermal facility, the drilling of the additional interconnecting pipes is completed by means of a service pipe, where the first part of the additional interconnecting pipes is used to connect the service pipe to the inlet pipe, and the second part of the additional interconnecting pipes is used to connect the service pipe to the outlet pipe. Thus, only one service pipe can be used, and this service pipe does not need to be located near the inlet pipe or the outlet pipe. For example, the service pipe can be arranged at an intermediate position between the inlet pipe and the outlet pipe.

[0026] By drilling a service pipe, a brand-new geothermal well system can be installed. Starting from the bottom of the service pipe, drilling can be carried out in a substantially horizontal (but not necessarily horizontal) direction in opposite directions. Thus, longer distances for the inlet and outlet pipes can be achieved. Since the maximum distance for horizontal drilling starting from the bottom of the service pipe is approximately 2.5 kilometers, the distance between the inlet pipe and the outlet pipe can reach approximately 5 kilometers along the line of the drilled connecting pipe.

[0027] In a further improvement of the geothermal facility installation method, the drilling of the additional interconnecting pipe is accomplished by means of two service pipes, where the two service pipes are interconnected by drilling to form the additional interconnecting pipe. The first of the two service pipes can be arranged near the inlet pipe, and as a supplement or alternative, the second service pipe can be arranged near the outlet pipe. Thus, each service pipe can be arranged substantially parallel to its corresponding inlet pipe or outlet pipe.

[0028] In a further improvement of the geothermal facility installation method, a blocking element is used to fluidically block the connection between the first of the two service pipes and the interconnecting pipe, and a second blocking element is used to fluidically block the connection between the second of the two service pipes and the interconnecting pipe. Thus, the interconnecting pipe can be closed so that it is only fluidically connected to the inlet pipe and the outlet pipe.

[0029] In a further improvement of the geothermal facility installation method, in order to interconnect the additional interconnecting pipe with the inlet pipe and the outlet pipe so as to fluidically connect the inlet pipe and the outlet pipe through the additional interconnecting pipe, and additionally preferably, in order to use the blocking element to fluidically block the connection between the additional interconnecting pipe and the service pipe, the time span during which the operation must be interrupted is less than 50% of the time span required for drilling the additional interconnecting pipe by means of at least one service pipe. The time span is preferably less than 20%, more preferably less than 10% or less than 5% or less than 2%.

[0030] The inlet pipe and / or the outlet pipe can be arranged or installed inside the service pipe. This can reduce the number of pipes for installing the geothermal well system or the geothermal facility respectively. In any case, considering that the space inside the service pipe is not occupied by the inlet pipe and / or the outlet pipe respectively, the space is sufficient to accommodate any use of the service pipe.

[0031] The inlet pipe and the outlet pipe can be arranged or installed concentrically, preferably arranged within the service pipe, and more preferably arranged concentrically within the service pipe. This can be achieved by inserting the inlet pipe into the outlet pipe or vice versa. Thus, the heat transfer fluid to be heated flows downward closely along the inner wall of the inlet pipe, while the heated heat transfer fluid flows upward closely along the inner wall of the outlet pipe. When arranged within the service pipe, preferably the outlet pipe is arranged concentrically with the inlet pipe. Since the surrounding service pipe is flushed with a cooler fluid, the heat transfer fluid will maintain a relatively high energy level on its way up to the surface level. Additionally, preferably the inlet pipe is arranged within the outlet pipe.

[0032] One advantage of the present invention is to reduce the cost of geothermal extraction. Another advantage of the present invention is to improve the efficiency of geothermal extraction. Still another advantage of the present invention is to improve the reliability of the operation of the extraction method. Brief Description of the Drawings

[0033] The disclosed technology will be described in more detail in conjunction with the drawings in a symbolic and illustrative manner. The drawings are described in a combined and general manner. The same reference numerals represent the same components, and reference numerals with different superscripts represent functionally equivalent or similar components.

[0034] In the drawings:

[0035] Figure 1A-1F : is a schematic diagram of the installation of a geothermal well system;

[0036] Figure 2A-2E : is a schematic diagram of the installation of a geothermal facility according to a first embodiment;

[0037] Figure 3A-3E : is a schematic diagram of the installation of a geothermal facility according to a second embodiment;

[0038] Figure 4A-4F : is a schematic diagram of the installation of a geothermal facility according to a third embodiment; and

[0039] Figure 5 : is a schematic diagram of a geothermal facility according to a fourth embodiment. Detailed Description of the Embodiments

[0040] Figures 1A to 1F Shows the installation of a geothermal well system 100. The geothermal well system 100 includes an inlet pipe 2 and an outlet pipe 4, and may also include a service pipe 6 ( Figure 1A ), wherein the pipes 2, 4, 6 are preferably drilled downward from the surface 150. Preferably, these pipes 2, 4, 6 are substantially vertical. When constructing the geothermal well system 100 according to Figures 1B to 1F a service pipe 6 is required.

[0041] Figure 1Bshows the first part 10' of the interconnected pipes drilled from the bottom of the service pipe 6. At Figure 1C In another step shown, the first part 10' of the interconnected pipes is fluidly connected to the inlet pipe 2 through the connecting part 11'. Figure 1C and 1D shows the second part 10” of the interconnected pipes 10', 10” being drilled, and the connecting part 11” being drilled that connects the second part 10” of the interconnected pipes to the outlet pipe 4. It does not matter whether the service pipe 6 is fluidly connected to the inlet pipe 2 or the outlet pipe 4 first.

[0042] Figure 1E shows the inlet pipe 2 and the outlet pipe 4 connected by the interconnected pipes 10', 10”, 11', 11”, and all components of the interconnected pipes 10', 10”, 11', 11” are formed by drilling through the service pipe 6. In addition, in addition to Figure 1E the elements shown, Figure 1F also shows a blocking element 30' that is preferably inserted at the bottom end of the service pipe 6 so as to keep the cross-section of the interconnected pipes 10', 10”, 11', 11” unobstructed for the heat transfer fluid to flow through unhindered. In any case, the geothermal well system 100 that forms the basis for the further installation of the geothermal facility necessarily includes the inlet pipe 2, the outlet pipe 4, and the interconnected pipes 10', 10”, 11', 11”.

[0043] Figure 2A 、 3A 、4A shows the geothermal well system 100 according to different embodiments. Figure 2B to 2F, 3B to 3E and 4B to 4F show the manufacture of the geothermal facility 200 based on Figure 2A 、 3A and the corresponding geothermal well system 100 shown in 4A.

[0044] The geothermal well system 100 includes an inlet pipe 2, interconnected pipes 10, and an outlet pipe 4, which are located below the ground surface 150. The inlet pipe 2 and the outlet pipe 4 are preferably substantially vertical. When the geothermal well system 100 is manufactured by means of the service pipe 6, there may be a large horizontal distance D (as shown in Figure 2) between the inlet pipe 2 and the outlet pipe 4. The geothermal well system 100 may include the service pipe 6 and the blocking element 30', and the interconnected pipes 10', 10”, 11', 11” may contain different parts due to this manufacturing method, as Figures 1A to 1F shown.

[0045] Figure 2B shows Figure 2AAll elements in and the first part 12' of the additional interconnected pipes drilled above the interconnected pipes 10', 10", 11', 11" in the direction towards the inlet pipe 2. Figure 2C Shows the second part 12" of the additional interconnected pipes drilled in the direction towards the outlet pipe 4 at the same level as the corresponding first part 12'. Figure 2D Shows that the two parts of the additional interconnected pipes 12', 12" are respectively connected to the inlet pipe 2 and the outlet pipe 4 by drilling the corresponding connecting parts 13', 13", so that the additional interconnected pipes 12', 12", 13', 13" are fluidly connected to the inlet pipe 2 and the outlet pipe 4.

[0046] Figure 2E Shows the inserted blocking element 20. The service pipe 6 passing through the blocking element 20 forms a straight line near the blocking element 20 because it extends in a straight line in a section from the horizontal height above the blocking element 20 to the horizontal height below the blocking element 20. The blocking element 20 is arranged outside the straight section of the service pipe 6. Therefore, the service pipe 6 has a free cross-section that is not blocked by the blocking element 20.

[0047] After inserting the blocking element 20, the fluid connection between the service pipe 6 and the additional interconnected pipes 12', 12", 13', 13" is disconnected, and the geothermal facility 200 then constitutes a closed-loop system. When the fluid connection between the service pipe 6 and the interconnected pipes 10', 10", 11', 11" is disconnected, the geothermal facility 200 can operate. Therefore, during operation, the heat transfer fluid flows through or is pumped to the inlet pipe 2, the interconnected pipes 10', 10", 11', 11", the additional interconnected pipes 12', 12", 13', 13", and the outlet pipe 4 respectively.

[0048] Figure 3B and 4B Also shows two drilled service pipes 6', 6". The first service pipe 6' is assigned to the inlet pipe 2, and the second service pipe 6" is assigned to the outlet pipe 4. Each service pipe 6', 6" is preferably oriented to be substantially parallel to its inlet pipe 2 or outlet pipe 4 respectively. An additional interconnected pipe 12 is drilled at the bottom of the service pipes 6', 6", which will be fluidly connected to the inlet pipe 2 and the outlet pipe 4 later. Figure 4B Shows the method steps for installing at least one additional interconnected pipe 12 above the existing interconnected pipe 10, so that the pipe is located between the existing interconnected pipe 10 and the ground surface (as Figure 4B shown). Figure 3B Shows the method steps for installing at least one additional interconnected pipe 12 below the existing interconnected pipe 10. Therefore, the horizontal height of the additional interconnected pipe 12 is lower than that of the existing interconnected pipe 10.

[0049] Figure 3C and 4C respectively show the connection of the additional interconnecting pipe 12 with the inlet pipe 2 and the outlet pipe 4. By drilling the corresponding connecting parts 13' and 13'', the additional interconnecting pipe 12 can be fluidly connected to the inlet pipe 2 and the outlet pipe 4. Before this connection is achieved, the operation of the geothermal well system 100 must be stopped / interrupted. Figure 3D and 4D also show the inserted blocking elements 20' and 20'' for fluidly disconnecting the service pipes 6' and 6'' from the additional interconnecting pipe 12. After the service pipes 6' and 6'' are fluidly disconnected from the additional interconnecting pipe 12 and the inlet pipe 2 and the outlet pipe 4, and thus the geothermal facility 200 becomes a closed-loop system, the geothermal facility 200 can start operating. Therefore, the heat transfer fluid flows downward through the inlet pipe 2, through the interconnecting pipe 10 and the additional interconnecting pipe 12, and upward through the outlet pipe 4.

[0050] Figure 3E and 4E also show a second additional interconnecting pipe 14 through the service pipes 6' and 6''. In addition, Figure 4F show the connecting parts 15' and 15'' for fluidly connecting the second additional interconnecting pipe 14 to the inlet pipe 2 and the outlet pipe 4 respectively. Figure 4F also show the inserted blocking elements 22' and 22'' for fluidly disconnecting the second additional interconnecting pipe 14 from the service pipes 6' and 6''. After the interconnecting pipes 12 and 14 are fluidly disconnected from the service pipes 6, 6' and 6'', the geothermal facility can operate. Therefore, at least one additional interconnecting pipe 14 can be added to the Figure 2A 、 3A and the geothermal facility of the geothermal well system 100 shown in 4A.

[0051] Figure 5 shows the geothermal facility 200 installed in the geological formation. The geothermal facility 200 includes an inlet pipe 2, an outlet pipe 4 and service pipes 6. The inlet pipe 2 and the outlet pipe 4 are arranged within the service pipes 6. The service pipes are flushed with cooler water. The outlet pipe 4 is preferably concentrically arranged within the inlet pipe 2 because the cooling rate of the heat transfer fluid is significantly slower only when the external ambient temperature is determined by the cold liquid flowing through the inlet pipe 2. The geothermal facility 200 may also include a control building 250, which may be built on the ground surface. The geothermal facility 200 includes an interconnecting pipe 10, which is the only interconnecting pipe 10 of the previous geothermal well system. Thereafter, at least one second interconnecting pipe 12, 14, 14' is installed according to the installation steps described herein. The interconnecting pipes 10, 12, 14, 14' can be oriented in different horizontal directions to utilize the local characteristics of the geological formation.

[0052] The following figures illustrate, by way of example, different embodiments of the subject matter of the present invention.

[0053] Those skilled in the art should understand that the illustration of the elements in the figures is intended to be concise and clear and is not necessarily drawn to scale. For example, for the purpose of assisting in understanding the present invention and its embodiments, the dimensions may be exaggerated relative to other elements. In addition, when terms such as "first", "second", etc. are used herein, their purpose is to distinguish similar elements and not necessarily to describe an order or a temporal order. Moreover, relative terms such as "front", "rear", "top", and "bottom" in the specification and / or claims do not necessarily describe an exclusive relative position. Therefore, those skilled in the art should understand that these terms can be interchanged with other terms and that the embodiments described herein can be operated in orientations different from those explicitly shown or otherwise described.

[0054] Detailed Description of the Preferred Embodiment

[0055] The following description is not intended to limit the scope of the present invention in any way. It is essentially exemplary and is intended to describe the best mode known to the inventors as of the filing date. Therefore, without departing from the spirit and scope of the present invention, changes can be made to the arrangement and / or function of any element described in the exemplary embodiments disclosed herein.

Claims

1. A method for installing a geothermal facility in a geological formation, comprising the following steps - Operating a geothermal well system, the geothermal well system including an inlet pipe, an outlet pipe, and an interconnecting pipe, the interconnecting pipe being in fluid communication with the inlet pipe and interconnecting the inlet pipe with the outlet pipe; Drilling an additional interconnecting pipe by means of at least one service pipe - When the geothermal well system is not operating, interconnecting the additional interconnecting pipe with the inlet pipe and the outlet pipe to fluidly connect the inlet pipe with the outlet pipe through the additional interconnecting pipe; and - Using a blocking element to fluidly block the connection between the additional interconnecting pipe and the service pipe.

2. The method for installing a geothermal facility according to claim 1, wherein, The drilling of the additional interconnecting pipe is accomplished by means of one service pipe, wherein the first part of the additional interconnecting pipe drilled is for connecting the service pipe with the inlet pipe, and the second part of the additional interconnecting pipe drilled is for connecting the service pipe with the outlet pipe.

3. The method for installing a geothermal facility according to claim 1, wherein, The drilling of the additional interconnecting pipe is accomplished by means of two service pipes, wherein the two service pipes are interconnected by drilling to form the additional interconnecting pipe.

4. The method for installing a geothermal facility according to claim 3, wherein, The blocking element is used to fluidly block the connection between the first of the two service pipes and the interconnecting pipe, and a second blocking element is used to fluidly block the connection between the second of the two service pipes and the interconnecting pipe.

5. The method for installing a geothermal facility according to claim 1, wherein - In order to interconnect the additional interconnecting pipe with the inlet pipe and the outlet pipe to fluidly connect the inlet pipe with the outlet pipe through the additional interconnecting pipe, and additionally - Preferably, in order to use a blocking element to fluidly block the connection between the additional interconnecting pipe and the service pipe, The time span during which the operation must be interrupted is less than 50% of the time span required to drill the additional interconnecting pipe by means of at least one service pipe.

6. The method for installing a geothermal facility according to claim 1, wherein the inlet pipe and the outlet pipe are installed within the service pipe, optionally in a concentric manner within the service pipe.

7. The method for installing a geothermal facility according to claim 1, wherein the inlet pipe and the outlet pipe are installed in separate boreholes.

8. A geothermal facility within a geological formation, comprising: An inlet pipe, An outlet pipe, A service pipe, and Two interconnecting pipes, the interconnecting pipes being in fluid communication with the inlet pipe and respectively interconnecting the inlet pipe with the outlet pipe, characterized in that the first interconnecting pipe is fluidly isolated from the service pipe by a blocking element, the blocking element being arranged in the pipe interconnecting the first interconnecting pipe with the service pipe.

9. The geothermal facility according to claim 8, wherein the inlet pipe and the outlet pipe are concentrically arranged.

10. The geothermal facility according to claim 9, wherein the inlet pipe and the outlet pipe are arranged within the service pipe.

11. The geothermal facility according to claim 10, wherein the inlet pipe and the outlet pipe are concentrically arranged within the service pipe, preferably the outlet pipe 4 is arranged within the inlet pipe 2.

12. The geothermal facility according to claim 8, wherein the inlet pipe and the outlet pipe are arranged in separate boreholes.

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