EP4630737A1

EP4630737A1 - Method for installing a geothermal installation and a geothermal installation

Info

Publication number: EP4630737A1
Application number: EP23901740.3A
Authority: EP
Inventors: Alain Jaccard; Lucien Vouillamoz; Arturs BLINOVS; Marcel Thomas KNEBEL; Gerardus Godefridus Johannes VAN OG; Naomi VOUILLAMOZ
Original assignee: Eaposys Sa
Current assignee: Eaposys Sa
Priority date: 2022-12-09
Filing date: 2023-12-15
Publication date: 2025-10-15
Also published as: WO2024124257A1; CN120322646A

Abstract

A method for installing a geothermal installation within a geologic formation including the steps of: - operating a geothermal well system, the geothermal well system comprising an inlet conduit, an outlet conduit and an interconnecting conduit, the interconnecting conduit fluidly coupled to and interconnecting the inlet conduit with the outlet conduit; - drilling an additional interconnecting conduit with the help of at least one service conduit; - interconnecting the additional interconnecting conduit with both the inlet conduit and the outlet conduit for fluidly coupling the inlet conduit with the outlet conduit through the additional interconnecting conduit, while the geothermal well system is not operated; and - fluidly blocking the connection between the additional interconnecting conduit with the service conduit using a blocking element is provided. Furthermore, a geothermal installation is provided.

Description

METHOD FOR INSTALLING A GEOTHERMAL INSTALLATION AND A GEOTHERMAL INSTALLATION

Identification of parties concerned

The Applicant of the present intellectual property matter is Eaposys SA of Bienne, Switzerland. The inventor(s) of the invention described in this patent documentation is/are Lucien Vouillamoz of Feusisberg, Switzerland, Naomi Vouillamoz, of Bienne, Switzerland, Alain Jaccard, of Sainte-Croix, Switzerland, Marcel Thomas Knebel, of Hoogeveen, The Netherlands, Arturs Blinovs, of Hoogeveen, The Netherlands, and Gerardus Godefridus Johannes Van Og, of Hoogeveen, The Netherlands.

Copyright & Legal Notice

A portion of the disclosure of this patent document contains material which is subject to copyright protection. The Applicant has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever. Further, no references to third party patents or articles made herein is to be construed as an admission that the present invention is not entitled to antedate such material by virtue of prior invention.

Background of the Invention

This invention relates to a geothermal installation and a method for installing a geothermal installation.

Geothermal energy is a form of thermal energy that uses the natural heat of the Earth. Geothermal energy is a source of renewable energy and is not an intermittent source of energy like solar and wind, which depend on the sun or wind to generate electricity. There is a growing need for dispatchable sources of renewable energy and energy storage solutions. Methods and equipment for generating dispatchable and reliable renewable energy are continuously sought. Conventional geothermal (hydrothermal) resources require the presence of three main factors: 1) sufficiently high temperatures in the subsurface; 2) the presence of hot, fluid bearing geologic formations or structures; and 3) a sufficiently high transmissivity of the rock to enable the requisite production and re-injection rates of geothermal brines. In order to be enable geothermal generation of electricity where a hydrothermal resource is not available (i.e. use a petrothermal resource), cold fluid is injected into the hot rock that has been previously fractured to provide a large heat exchange area. This is known as Enhanced Geothermal System (EGS). Cold fluid percolates through the engineered subsurface 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). EGS have several drawbacks: 1) the surface created for heat exchange by hydraulic reservoir stimulation (i.e. injecting fluids under high-pressure to create an interconnected fracture network) remains largely uncontrolled in terms of geometry and size and does not necessarily ensure optimal fluid flow rate for industrial exploitation; 2) hydraulic reservoir stimulation is accompanied by induced seismicity and microseisms can grow into larger earthquakes, which represent a danger to the inhabitants on the surface, and ultimately limit the installations’ sustainability.

Further disadvantages of fracking include the requirement for extremely high pressures to break up the underground rock, and as a consequence an important part of the liquid which is injected in the bedrock to frack it infiltrates too far and doesn’t get recovered.

The evolution of geothermal energy collection has now led to the concept of closed-loop systems, where the heat transfer fluid is circulated within an array of tunnels with minimal leakages, avoiding the drawbacks of EGS systems.

Different prior art discloses that the operation of a geothermal installation needs to be stopped while an expansion of the installation takes place. Nevertheless, there is a need for thermal energy in performing the expansion work. Therefore, it is an object of the invention to provide a method for installing a geothermal installation which can be more efficiently used.

Summary of the Invention

This task is accomplished by a method for installing a geothermal installation within a geologic formation comprising the following steps:

- operating a geothermal well system, the geothermal well system comprising an inlet conduit, an outlet conduit and an interconnecting conduit, the interconnecting conduit fluidly coupled to and interconnecting the inlet conduit with the outlet conduit;

- drilling an additional interconnecting conduit with the help of at least one service conduit;

- interconnecting the additional interconnecting conduit with both the inlet conduit and the outlet conduit for fluidly coupling the inlet conduit with the outlet conduit through the additional interconnecting conduit, while the geothermal well system is not operated; and

- fluidly blocking the connection between the additional interconnecting conduit with the service conduit using a blocking element.

This task is also accomplished by a geothermal installation within a geologic formation comprising an inlet conduit, an outlet conduit, a service conduit, and two interconnecting conduits, the interconnecting conduits fluidly coupled to and separately interconnecting the inlet conduit with the outlet conduit, characterized in that a first of the interconnection conduits is fluidly separated from the service conduit by a blocking element, the blocking element being arranged in a conduit interconnecting the first interconnection conduit with the service conduit.

A conduit according to the present application may be understood as a wellbore unless otherwise stated.

An existing geothermal well system within a geologic formation, which is preferably a closed loop system, includes an inlet conduit, an outlet conduit and at least one interconnecting conduit. Orientation of the inlet and outlet conduits is preferably substantially vertical. Orientation of the interconnecting conduit is preferably horizontal. Therefore, a heat transfer fluid, preferably a heat transfer liquid, flows downwardly within the inlet conduit into the geologic formation, flows through the at least one interconnecting conduit and flows upwardly within the outlet conduit, mainly absorbing heat energy while flowing within the interconnecting conduit. Within the application the (additional) interconnecting conduits may be understood to be micro-tunnels. According to technical necessities these micro-tunnels may need to be cased or lined. The inlet and outlet conduits may be installed or arranged separate from each other.

Without the need of further mention, it is clear that the conduits may be furnished with pipes or other suitable elements for the heat transfer fluid to flow in. As it is obvious that within the interconnecting conduit, for instance The material of the interconnecting conduit, for instance a pipe, may be chosen to fulfill the specific technical parameters. The interconnecting conduits may also be cased or lined, in order to facilitate the circulation of the heat transfer fluid and the thermal exchange between the heat transfer fluid and the surrounding geological formation. Such a blocking element can be a blocking valve, a plug, a shut-off valve or any other element capable of substantially closing the fluid connection between the additional interconnecting conduit and the service conduit to block fluid flowing.

It was realized that the existing geothermal well system can be expanded while being operated during the drilling of the additional interconnecting conduit and the equipping of the interconnecting conduit with necessary technical elements. For drilling the additional interconnecting conduit the at least one service conduit is used, as this could be the drillhead and its mechanical controlling equipment. The operation of the existing geothermal well system has to be stopped, particularly interrupted, only for fluidly coupling the additional interconnecting conduit with both the inlet and the outlet conduit and preferably during inserting the blocking element to fluidly decouple the service conduit from the additional interconnecting conduit. Therefore the already existing geothermal well system can be operated a long time during the still ongoing installation of the geothermal installation. More precisely, the already existing geothermal well system may be operated at least during the drilling of the additional conduit. The blocking element is necessary during operation of the geothermal installation to close the additional interconnecting conduit to be fluidly connected only to the inlet and outlet conduits. In other words, after the at least one necessary blocking element is placed for fluidly decoupling the additional interconnecting conduit from the service conduit, the geothermal installation includes the geothermal well system and the additional interconnecting conduit may be operated. Preferably, if the service conduit is formed straightly lined at least within segments, the blocking element is arranged or placed outside this straight-lined segment, to still allow access from the service conduit to other interconnecting conduits arranged at a lower horizontal level for further construction or maintenance.

The service conduit is used to insert, operate and remove a drilling system, preferably a micro-tunnel drilling system. The drilling system ends with a segment which allows for orientation of a drilling head of the drilling system in an intended direction, b.) the fixing of the drilling system tightly within the service conduit and c.) the release of the drilling system from this fixation. The service conduit allows a), a circulation without leakage of the drilling muds to the surface, the drilling muds resulting of the drilling conduits, and b). at the end of the drilling, the introduction and fixing of the blocking element, and to connect the blocking element within the conduit, preferably within the service conduit to keep the additional interconnecting conduit open for the heat transfer fluid to flow within the additional interconnecting conduit. After venting the additional connecting conduit and removing the drill head, the blocking element may be placed and put into its blocking position, the heat transfer fluid substantially not being able to pass the blocking element, while in its blocking position.

Before interconnecting the additional interconnecting conduit with the inlet conduit and/or the outlet conduit for fluidly coupling the inlet conduit, a beacon (radioactive or electromagnetic) source may be placed at the end of the drilled connection conduits for facilitating the connection with the inlet or outlet conduits respectively.

During operation the heat transfer fluid is circulating through the inlet conduit, through the interconnecting conduit(s), through the outlet conduit, absorbing heat while flowing therethrough, particularly when flowing through the interconnecting conduit(s) of the geothermal installation within a geologic formation or a geothermal well system respectively. For the case in which the original geothermal well system is a closed loop system the resulting geothermal installation is a closed loop system as well.

Within a further development of the method for installing a geothermal installation, the drilling of the additional interconnecting conduit being accomplished with the help of one service conduit, wherein a first part of the additional interconnecting conduit is drilled for connecting the service conduit with the inlet conduit and a second part of the additional interconnecting conduit is drilled for connecting the service conduit with the outlet conduit. Therefore, it is possible to use only one service conduit which does not need to be situated in the vicinity of either the inlet or the outlet conduit. The service conduit, for example, may be arranged halfway between the inlet conduit and the outlet conduit.

By drilling one service conduit it is possible to install a complete new geothermal well system. From the bottom of the service conduit the substantially but not necessarily horizontal drilling can be done in opposite directions. Therefore, a greater distance of the inlet and outlet conduits can be accomplished. As the maximal distance from the bottom of the service conduit to drill in a horizontal direction is exemplarily about 2.5 km it is possible for the inlet and outlet conduits to have a distance of about 5 km in the line of the drilled connection conduits.

Within a further development of the method for installing a geothermal installation, the drilling of the additional interconnecting conduit is accomplished with the help of two service conduits, wherein the two service conduits are interconnected by drilling to create the additional interconnecting conduit. A first of the two service conduits may be arranged in the vicinity of the inlet conduit and additionally or alternatively the second service conduit may be arranged in the vicinity of the outlet conduit. Therefore, each of the service conduits may be arranged substantially parallel to its corresponding inlet or outlet conduit.

Within a further development of the method for installing a geothermal installation the blocking element is used for fluidly blocking the connection between a first of the two service conduits and the interconnecting conduit and a second blocking element is used for fluidly blocking the connection between the second of the two service conduits and the interconnecting conduit. It is therefore possible to close the interconnecting conduit so that it is only fluidly connected to the inlet and outlet conduits.

Within a further development of the method for installing a geothermal installation, a time span, when the operation is necessarily interrupted for interconnecting the additional interconnecting conduit with both the inlet conduit and the outlet conduit for fluidly coupling the inlet conduit with the outlet conduit through the additional interconnecting conduit, and additionally preferably for fluidly blocking the connection between the additional interconnecting conduit with the service conduit using the blocking element is less than 50% of the time span for drilling the additional interconnecting conduit with the help of the at least one service conduit. The said time span is preferably less than 20%, more preferably less than 10% or less than 5% or less than 2%.

The inlet conduit and/or the outlet conduit may be arranged or installed within the service conduit. This provides the opportunity of reducing the number of conduits for installing a geothermal well system or geothermal installation respectively. Anyhow, given that the space within the service conduit is not occupied by the inlet conduit and/or outlet conduit, respectively, is large enough for any action the service conduit is built for.

The inlet conduit and the outlet conduit may be arranged or installed concentric, preferably within the service conduit, more preferably concentrically within the service conduit. This could be realized by inserting an inlet pipe into an outlet pipe or vice versa, and consequently, the heat transfer fluid to be heated flows downwardly in the immediate vicinity of the inner wall of the of the inlet pipe and the heated heat transfer fluid flows upwardly in the immediate vicinity of the inner wall of the outlet pipe. When arranged within the service conduit, the outlet conduit is preferably concentrically arranged within the inlet conduit. As the surrounding service conduit is flushed with rather cold fluid, the heat transfer fluid would stay at a greater level of energy on the way up to the level of the surface of the earth. It is also preferable to arrange the inlet conduit within the outlet conduit. In an advantage, the invention reduces the costs of the extraction of geothermal heat. In another advantage, the invention increases the efficiency of the extraction of geothermal heat. In still another advantage, the invention improves the reliability of the functioning of the method of extraction.

Brief Description of the Drawings

The disclosed technologies are explained in more detail symbolically and by way of example on the basis of the figures. The figures are described conjunctively and in general. The same reference numerals signify the same components and reference numerals with different indices indicate functionally equivalent or similar components.

In the drawings:

FIGs 1 A - F: are schematic views of an installation of a geothermal well system;

FIGs 2 A - E: are schematic views of the installation of a geothermal installation according to a first embodiment;

FIGs 3 A - E: are schematic views of the installation of a geothermal installation according to a second embodiment;

FIGs 4 A - F: are schematic views of the installation of a geothermal installation according to a third embodiment; and

FIG 5: a schematic view of a geothermal installation according to a fourth embodiment.

FIGs 1 A to IF show an installation of a geothermal well system 100. The geothermal well system 100 includes an inlet conduit 2 and an outlet conduit 4, and may additionally comprise a service conduit 6 (FIG 1 A), wherein the conduits 2, 4, 6 were preferably drilled downwardly from the surface 150 of the earth. Preferably these conduits 2, 4, 6 are substantially plumb. The service conduit 6 is needed when the geothermal well system 100 is fabricated according to FIGs IB to IF. FIG IB shows a first part 10’of an interconnecting conduit being drilled from the bottom of the service conduit 6. In a further step being shown within FIG 1C the first part 10’ of the interconnecting conduit is fluidly connected to the inlet conduit 2 by a connecting part 11 ’. FIGs 1C and ID show a second part 10” of the interconnecting conduit 10’, 10” is being drilled and a connecting part 11” being drilled to connect the second part 10” of the interconnecting conduit with the outlet conduit 4. It is not of importance whether the service conduit 6 is firstly fluidly connected with the inlet conduit 2 or the outlet conduit 4.

FIG IE shows the inlet and outlet conduits 2, 4 being connected by the interconnecting conduit 10’, 10”, 11’, 11”, all the parts of the interconnecting conduit 10’, 10”, 11 ’, 11” resulting of a drilling through the service conduit 6. Additionally, to the elements shown in FIG IE, FIG IF shows a blocking element 30’ inserted within preferably the bottom end of the service conduit 6, so that the cross section of the interconnecting conduit 10’, 10”, 11’, 11” is kept free for unhindered flow of heat transfer fluid. Anyhow the geothermal well system 100 as a basis for a further installation of a geothermal installation necessarily includes an inlet conduit 2, an outlet conduit 4 and an interconnecting conduit 10’, 10”, 11’, 11”

FIGs 2A, 3 A, 4A show a geothermal well system 100 according to different embodiments. The FIGs 2B to 2F, 3B to 3E and 4B to 4F show the fabrication of a geothermal installation 200 based on the respective geothermal well system 100 shown in FIGs 2A, 3 A and 4A.

The geothermal well system 100 includes a inlet conduit 2, an interconnecting conduit 10, and an outlet conduit 4 arranged underneath a surface 150 of the earth. The inlet conduit 2 and the outlet conduit 4 are preferably substantially plumb line. When the geothermal well system 100 is fabricated with the help of a service conduit 6 possibly to have a high horizontal distance D between the inlet conduit 2 and the outlet conduit 4 as it is shown in FIG 2 the geothermal well system 100 may include a service conduit 6 and a blocking element 30’ and the interconnecting conduit 10’, 10”, 11’, 11” may comprise different parts due to such a fabrication as it is described within FIGs 1A to IF. FIG 2B shows all elements of FIG 2A and a first part 12’ of an additional interconnecting conduit drilled above the interconnecting conduit 10’, 10”, 11 ’, 11” into the direction of the inlet conduit 2. FIG 2C shows a second part 12” of the additional interconnecting conduit drilled at the same level as the respective first part 12’ into the direction of the outlet conduit 4. FIG 2D shows the connecting of the two parts of the additional interconnecting conduit 12’, 12” with the inlet and the outlet conduit 2, 4 respectively by drilling respective connecting parts 13’, 13” for the additional interconnecting conduit 12’, 12”, 13’, 13” to be fluidly connected to the inlet and outlet conduits 2, 4.

FIG 2E shows the inserted blocking element 20. The service conduit 6 passing the blocking element 20 substantially forms a straight line in the vicinity of the blocking element 20, as it runs straight-lined in a segment of the service conduit 6 from a horizontal level above the blocking element 20 to a horizontal level underneath the blocking element 20. The blocking element 20 is arranged outside of that straight-lined segment of the service conduit 6. Therefore the service conduit 6 has a free cross section which is not blocked by the block element 20.

The blocking element 20 being inserted having fluidly disconnected the service conduit 6 from the additional interconnecting conduit 12’, 12”, 13’, 13” the geothermal installation 200 is a closed loop system. The geothermal installation 200 can be operated, as the service conduit 6 is being fluidly disconnected from the interconnecting conduit 10’, 10”, 11’, 11”. Therefore, during operation heat transfer fluid is flowing or pumped respectively through the inlet conduit 2, the interconnecting conduit 10’, 10”, 11’, 11”, the additional interconnecting conduit 12’, 12”, 13’, 13” and the outlet conduit 4.

FIGs 3B and 4B furthermore show drilled two service conduits 6’, 6”. A first service conduit 6’ is assigned to the inlet conduit 2 and the second service conduit 6” is assigned to the outlet conduit 4. Each of the service conduits 6’, 6” is preferably oriented substantially parallel to its inlet or outlet conduit 2, 4 respectively. An additional interconnecting conduit 12 to be lateron fluidly connected to the inlet and outlet conduits 2, 4 is drilled at the bottom of the service conduits 6’, 6”. FIG 4B shows the method step towards installing at least one additional interconnecting conduit 12 above the existing interconnecting conduit 10 therefore between the existing interconnecting conduit 10 and the surface of the earth, indicated in FIG 4B. FIG 3B shows the method step towards installing at least one additional interconnecting conduit 12 underneath the existing interconnecting conduit 10. Therefore, the additional interconnecting conduit 12 is at a lower horizontal level than the existing interconnecting conduit 10.

FIGs 3C and 4C show the connecting of the additional interconnecting conduit 12 with the inlet and outlet conduit 2, 4 respectively by drilling respective connecting parts 13’, 13” for the additional interconnecting conduit 12 to be fluidly connected to the inlet and outlet conduits 2, 4. Before that connecting is realized the operation of the geothermal well system 100 has to be stopped/interrupted. FIGs 3D and 4D additionally show inserted blocking elements 20’, 20” to fluidly disconnect the service conduits 6’, 6” from the additional interconnecting conduit 12. After the service conduits 6’, 6” are fluidly disconnected from the additional interconnecting conduit 12 and the inlet and outlet conduits 2, 4 and therefore the geothermal installation 200 being a closed loop system, the operation of the geothermal installation 200 can be started, therefore the heat transfer fluid flowing downwardly through the inlet conduit 2, and flowing through the interconnecting conduit 10 and through the additional interconnecting conduit 12, and flowing upwardly through the outlet conduit 4.

FIGs 3E and 4E furthermore show a second additional interconnecting conduit 14 drilled through the service conduits 6’, 6”. Furthermore, FIG 4F shows connecting parts 15’, 15” to fluidly connect the second additional interconnecting conduit 14 to the inlet and outlet conduits 2, 4 respectively. FIG 4F additionally shows inserted blocking elements 22’, 22” to fluidly disconnect the second additional interconnecting conduit 14 from the service conduits 6’, 6”. Immediately after fluidly disconnecting the interconnecting conduits 12, 14 from the service conduit 6, 6’, 6” the geothermal installation can be operated. Therefore at least one more additional interconnecting conduits 14 may be added to the geothermal installation to the geothermal well system 100 shown in FIGs 2A, 3 A and 4A.

FIG 5 shows a geothermal installation 200 which is installed within a geologic formation. The geothermal installation 200 includes an inlet conduit 2, an outlet conduit 4 and a service conduit 6. The inlet conduit 2 and the outlet conduit 4 are arranged within the service conduit 6. The service conduit is flushed with rather cold water. The outlet conduit 4 is preferably concentrically arranged within the inlet conduit 2, as the heat transfer fluid would cool down less significantly when only the temperature of the outer surrounding is defined by a cold liquid flowing through the inlet conduit 2. The geothermal installation 200 may also include a control building 250, possibly built on the surface of the earth. The geothermal installation 200 includes an interconnecting conduit 10 as the only interconnecting conduit 10 of a former geothermal well system. Afterwards at least one second interconnecting conduit 12, 14, 14’ is installed according to an installation procedure herein described. The interconnecting conduits 10, 12, 14, 14’ can be oriented in different horizontal direction to take advantage of the local characteristics of the geologic formation.

The below drawings represent, by way of example, different embodiments of the subject of the invention.

Those skilled in the art will appreciate that elements in the Figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, dimensions may be exaggerated relative to other elements to help improve understanding of the invention and its embodiments. Furthermore, when the terms 'first', 'second', and the like are used herein, their use is intended for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. Moreover, relative terms like 'front', 'back', 'top' and 'bottom', and the like in the Description and/or in the claims are not necessarily used for describing exclusive relative position. Those skilled in the art will therefore understand that such terms may be interchangeable with other terms, and that the embodiments described herein are capable of operating in other orientations than those explicitly illustrated or otherwise described.

Detailed Description of the Preferred Embodiment

The following description is not intended to limit the scope of the invention in any way as it is exemplary in nature, serving to describe the best mode of the invention known to the inventors as of the filing date hereof. Consequently, changes may be made in the arrangement and/or function of any of the elements described in the exemplary embodiments disclosed herein without departing from the spirit and scope of the invention.

Claims

Claims What is claimed is:

1. Method for installing a geothermal installation within a geologic formation comprising the following steps:

2. Method for installing a geothermal installation according to claim 1 , the drilling of the additional interconnecting conduit being accomplished with the help of one service conduit, wherein a first part of the additional interconnecting conduit is drilled for connecting the service conduit with the inlet conduit and a second part of the additional interconnecting conduit is drilled for connecting the service conduit with the outlet conduit.

3. Method for installing a geothermal installation according to claim 1, the drilling of the additional interconnecting conduit being accomplished with the help of two service conduits, wherein the two service conduits are interconnected by drilling to create the additional interconnecting conduit.

4. Method for installing a geothermal installation according to claim 3, wherein the blocking element is used for fluidly blocking the connection between a first of the two service conduits and the interconnecting conduit and a second blocking element is used for fluidly blocking the connection between the second of the two service conduits and the interconnecting conduit.

5. Method for installing a geothermal installation according to claim 1, wherein a time span, when the operation is necessarily interrupted for

- interconnecting the additional interconnecting conduit with both the inlet conduit and the outlet conduit for fluidly coupling the inlet conduit with the outlet conduit through the additional interconnecting conduit, and additionally

- preferably for fluidly blocking the connection between the additional interconnecting conduit with the service conduit using the blocking element is less than 50% of the time span for drilling the additional interconnecting conduit with the help of the at least one service conduit.

6. Method for installing a geothermal installation according to claim 1 , wherein the inlet conduit and the outlet conduit are installed within a service conduit, optionally in a concentric manner.

7. Method for installing a geothermal installation according to claim 1 , wherein the inlet conduit and the outlet conduit are installed within separate wellbores.

8. Geothermal installation within a geologic formation comprising: an inlet conduit, an outlet conduit, a service conduit, and two interconnecting conduits, the interconnecting conduits fluidly coupled to and separately interconnecting the inlet conduit with the outlet conduit, characterized in that a first of the interconnection conduits is fluidly separated from the service conduit by a blocking element, the blocking element being arranged in a conduit interconnecting the first interconnection conduit with the service conduit.

9. Geothermal installation according to claim 8, wherein the inlet conduit and the outlet conduit are arranged concentric.

10. Geothermal installation according to claim 9, wherein the inlet conduit and the outlet conduit are arranged within the service conduit.

11. Geothermal installation according to claim 10, wherein the inlet conduit and the outlet conduit are concentrically arranged within the service conduit, preferably the outlet conduit 4 arranged within the inlet conduit 2.

12. Geothermal installation according to claim 8, wherein the inlet conduit and the outlet conduit are arranged within separate wellbores.