Geothermal system comprising an energy production system
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-05-22
- Publication Date
- 2026-04-08
AI Technical Summary
Current geothermal systems fail to effectively manage heat exchanges with underground water tables and rivers, leading to harmful environmental changes and greenhouse gas emissions, as they do not adequately protect the environment during energy production and storage.
A geothermal system with a closed circuit heat transfer fluid system, including vertical geothermal probes with coaxial tubes and thermal insulation, which allows for controlled energy storage and extraction while minimizing thermal impact on groundwater and surrounding soil, using a geothermal energy storage system that exploits the thermal inertia of the subsoil and incorporates a charge and discharge control system to manage energy circulation.
The system reduces environmental impact by minimizing heat transfer to groundwater, enhances energy efficiency, and supports the production of heat, refrigeration, and electrical energy while eliminating fossil fuel use and reducing greenhouse gas emissions.
Smart Images
Figure EP2024064138_28112024_PF_FP_ABST
Abstract
Description
Description GEOTHERMAL SYSTEM COMPRISING AN ENERGY PRODUCTION SYSTEM Technical field
[0001] The invention relates to the technical field of geothermal systems. State of the art
[0002] Geothermal energy is a method of producing energy and electricity based on the exploitation of the natural heat of the subsoil which benefits from a thermal gradient of the order of 30°C every 1000m of average depth and the deeper the geothermal exchangers are, the more the geothermal gradient increases the operating temperature of the geothermal resource. There are several geothermal energy sectors depending on the operating temperature level. Geothermal energy can produce heating, electricity, hot water and air conditioning.
[0003] However, the sizing of the energy system requires defining the quantities of energy exchanged between the surface and buried equipment. From the quantity of energy used by the underground system, it is necessary to determine the thermal behavior of the underground system in relation to the environmental context. The systems known until now do not allow the environment to be protected from the underground elements of the system. In particular, heat exchanges can occur at the level of underground water tables and rivers, leading to harmful environmental changes.
[0004] The invention is therefore placed in this context and seeks to resolve all of the aforementioned drawbacks. Thus, the invention seeks to propose a geothermal system making it possible to combat global warming by eliminating the use of fossil fuels and reducing greenhouse gas emissions and protecting the environment in which the system is integrated while producing heat, and / or cooling and / or electrical energy. Presentation of the invention.
[0005] The invention relates to a geothermal system, comprising an energy production system capable of heating a heat transfer fluid; a system for transforming thermal energy from a heat transfer fluid; a geothermal energy storage system comprising at least one closed circuit for circulating a heat transfer fluid comprising at least a first heat transfer section connected to the energy production system, a second heat transfer section connected to the transformation system and at least one vertical geothermal probe comprising a first tube and a second tube arranged coaxially around said first tube, said probe being arranged in a borehole made in a ground and capable of storing or extracting thermal energy from this ground;a system for controlling a charging and discharging cycle of the storage system, arranged to control the circulation of the heat transfer fluid in the closed circulation circuit from the first section to the geothermal probe or from the geothermal probe to the second section according to a charging or discharging instruction of the geothermal system. The invention is remarkable in that the vertical geothermal probe comprises a first cold portion extending into the borehole and a second transfer portion extending into the borehole while being arranged below the first cold portion and in that the geothermal energy storage system comprises a thermal insulation member inserted against a wall of the second tube extending into the borehole only at the level of the first cold portion. ;
[0006] The energy production system can be a thermal energy production system. The heat transfer fluid can be a liquid heat transfer fluid. The heat transfer fluid can be a gaseous heat transfer fluid. The heat transfer fluid can be used to circulate in a closed circuit inside the tubes to extract or inject energy from the subsurface.
[0007] The first heat transfer section may be a first circulation member of a heat transfer fluid heated by the energy production system in the vertical geothermal exchanger to store thermal energy in the ground.
[0008] The second heat transfer section may be a second circulation member of a heat transfer fluid stored in the geothermal energy storage system to the transformation system to extract thermal energy from the ground. The energy storage system may allow heat to be stored by exploiting the thermal inertia of the subsoil through the heat capacity of the elements composing the subsoil in which the vertical geothermal probes are installed.
[0009] The charge and discharge control system may in particular include a short-term intermediate storage tank which can temporarily store the accumulated energy.
[0010] Each geothermal probe can be placed in a borehole formed by cementing by grout injection. This cementing can prevent any surface infiltration of pollution or connection of the water tables crossed. This cementing can allow the transfer of thermal energy between the subsoil and the tubes constituting the underground exchanger.
[0011] The geothermal probe can be a closed loop geothermal exchanger.
[0012] The thermal insulation member can limit energy losses. The thermal insulation member can limit the thermal impact of the device in contact with free or confined groundwater tables crossed. The thermal insulation member can limit the influence of the fluctuation of outside air temperatures in contact with the surface of the natural ground constituting a source of loss. The insulation member can limit the thermal impact of the device on the surface of the ground covering the storage device. The thermal insulation member can be inserted against a wall of the second tube. In one embodiment, the thermal insulation member can be mounted against an internal wall of said second tube and at a distance from the first tube at the first cold portion.In another embodiment, the thermal insulation member may be mounted against an external wall of said second tube and at a distance from the first tube at the first cold portion. Therefore, the use of the thermal insulation member may prevent heat transfer from being carried out from the. probe towards the surrounding ground and in particular towards the groundwater so as to preserve said water by not impacting it thermally.
[0013] The second transfer portion without thermal insulation can release its heat to the surrounding substrate. The heating part can thus be positioned outside the influence of groundwater flows, but also in a suitable geological substrate. This specific positioning of the heating part can increase the efficiency of the storage volume and adapt the injected energy power according to needs.
[0014] The geothermal system can be used to exploit injection temperatures in the subsoil, particularly up to 250°C. The probe can therefore be made of materials suitable for withstanding these types of temperatures.
[0015] The geothermal system can be designed to eliminate any risk of thermal impacts on the groundwater resource. The geothermal system can be designed to limit heat loss from the system into the subsoil. The geothermal system can be designed to limit the thermal impact on underground microbial life.
[0016] The geothermal system can be adapted to support the injection of heat transfer fluid to raise the temperature of a predefined volume of elements constituting the subsoil, in particular rocks. The geothermal system can generate cycles of injection and extraction of energy in the subsoil.
[0017] Advantageously, the closed circulation circuit of the energy storage system comprises a plurality of vertical geothermal probes connected in parallel and / or in series to a collector connected to the first and second transfer sections and arranged to distribute the heat transfer fluid to each of the vertical geothermal probes.
[0018] The collector may in one embodiment comprise a distributor function.
[0019] The collector can be arranged to distribute the heat transfer fluid to each of the vertical geothermal probes.
[0020] The energy storage system can recover excess thermal energy so that the heat produced can be stored for several months before being reused.
[0021] Advantageously, the energy production system comprises a solar power plant and / or an energy recovery plant.
[0022] The energy production system may advantageously comprise a solar thermal power plant. In another embodiment, the energy production system may comprise a photovoltaic solar power plant. The energy production system may comprise solar collectors for the production of heat, cooling and / or electrical energy. In another embodiment, the energy production system may comprise any so-called renewable energy source and / or recovery energy source, intermittent or continuous, local, decarbonized and renewable. In another embodiment, the energy production system may comprise a renewable thermal energy source. In another embodiment, the energy production system may comprise a recovery thermal energy source.In a different embodiment, the energy production system may comprise a source of recovery thermal energy greater than 70°, in particular greater than 90°.
[0023] The energy recovery plant can advantageously be based on the principle of recovering fatal energies.
[0024] Advantageously, the vertical geothermal probe comprises a first tube and a second tube arranged coaxially around the first tube, the tubes together forming said first and second portions of the vertical geothermal probe, the internal volume of the first tube defining a volume for injecting the heat transfer fluid heated by the energy production system and the volume formed between the first tube and the second tube defining a volume for transferring thermal energy to the ground for its storage during a charging cycle; and the volume formed between the first tube and the second tube defining a volume for transferring thermal energy from the ground and the internal volume of the first tube defining an extraction volume of the heat transfer fluid heated by the ground towards the transformation system during a discharge cycle.
[0025] The first tube may be pre-insulated steel. The first tube may be evacuated. The first tube may not be evacuated.
[0026] The second tube may be pre-insulated steel. The second tube may be evacuated. The second tube may not be evacuated.
[0027] The first and second tubes may comprise a plurality of layers. The first and second tubes may be adapted to reduce heat transfer by convection and / or conduction and / or radiation between the interior and the exterior.
[0028] During a charging cycle, the injection temperature of the heat transfer fluid at the probe inlet can be between 90 and 250°C.
[0029] During a discharge cycle, the injection temperature of the heat transfer fluid at the probe inlet can be higher than 40°C and the temperature of the heat transfer fluid at the probe outlet can be higher than 90°C.
[0030] The transformation system can direct the energy produced to homes and / or agricultural buildings and / or industrial buildings and / or heating, cooling and / or electrical energy networks.
[0031] Advantageously, the vertical geothermal probe comprises an external heat exchange layer arranged between an internal wall of the borehole and an external wall of the second tube.
[0032] The outer layer may be an external surface of the vertical geothermal probe. The outer heat exchange layer may have a diameter substantially similar to the borehole and adapted to surround said heat exchanger.
[0033] The external exchange layer can allow for homogeneous filling over the height of the borehole and can prevent surface infiltration of pollution or connection of the water tables crossed.
[0034] The external heat exchange surface of said SGV whose diameter is substantially similar to the borehole and adapted to surround said geothermal exchanger with injection cementing between the borehole and the exchanger geothermal allowing a homogeneous filling over the height of the borehole and avoiding the risk of surface infiltration of pollution or connection of the water tables crossed ensures the transfer of energy between the subsoil and the tubes constituting the underground exchanger.
[0035] Advantageously, the first tube comprises a plurality of tube sections arranged one after the other and held two by two by a fixing element.
[0036] The fasteners can advantageously be clip-on fittings. The fasteners can be of the screwed and / or notched sleeve type. The fasteners can be waterproof. The fasteners can be pre-insulated.
[0037] The arrangement using a plurality of tubes held two by two by fixing elements can allow the use of a probe of 30 m depth. In another embodiment, the probe can be 2000 m deep.
[0038] The second tube comprises a plurality of tube sections arranged one after the other and held two by two by a fixing element.
[0039] Advantageously, the vertical geothermal probe comprises a filtration member mounted on the first tube at the lower end of the second transfer portion.
[0040] The filtration member may comprise on the first tube, at the level of the lower end of the second transfer portion, a segment of perforated tube distributing the heat transfer fluid adapted for charging and discharging and the sum of the flow rates of each hole being equal to the flow rate of the heat transfer fluid.
[0041] The filtration member may be arranged to allow the passage of the heat transfer fluid from the internal volume of the first tube to the volume formed between the first tube and the second tube, and vice versa.
[0042] Advantageously, the vertical geothermal probe comprises a member for closing the second tube, mounted on the second tube at the lower end of the second transfer portion.
[0043] The closure member may comprise a solid tube segment. The closure member may be sealed. The closure member may be mounted at a lower end of the second tube, in particular in the transfer portion.
[0044] Advantageously, the heat transfer fluid comprises a liquid or gaseous fluid.
[0045] The heat transfer fluid can be used to ensure the exchange of energy between the tubes and the subsoil. The heat transfer fluid can be adapted to circulate in the tubes slowly enough to allow the transfer of heat energy by conduction.
[0046] The heat transfer fluid may include water, glycol, thermal oil and / or any other liquid that can accept a biodegradable heat load without impacting the environment.
[0047] Advantageously, the system for transforming thermal energy from a heat transfer fluid comprises a heat pump, a refrigeration machine, and / or a turbine.
[0048] The transformation system may include, depending on the energy uses to be covered, a direct supply of heat energy and / or a supply of heat energy associated with a heat pump and / or a production of cooling energy associated with a refrigeration machine and / or a supply of electricity associated with an electricity production module. Brief description of the figures.
[0049] Other advantages and characteristics of the present invention are now described with the aid of examples which are purely illustrative and in no way limitative of the scope of the invention, and from the appended drawings, drawings in which the various figures represent:
[0050] [Fig. 1] schematically represents a sectional view of two coaxial vertical probes inserted into a ground, one of the probes being in a charged state and the other of the probes being in a discharged state, according to one embodiment.
[0051] [Fig. 2] schematically represents a perspective view in section of a vertical probe head according to one embodiment
[0052] [Fig. 3] schematically represents a perspective view in section of a vertical probe foot according to one embodiment.
[0053] [Fig. 4] schematically represents a perspective view in section of a vertical probe integrated into a borehole in the ground, according to one embodiment.
[0054] [Fig. 5] schematically represents a perspective view in section of a geothermal system for storing underground energy from solar energy and comprising a plurality of vertical probes according to one embodiment.
[0055] [Fig. 6] schematically represents a perspective view in section of a geothermal system for storing underground energy from fatal energy and comprising a plurality of vertical probes according to one embodiment.
[0056] In the following description, elements which are identical, by structure or by function, appearing in different figures retain, unless otherwise specified, the same references. Description of an embodiment.
[0057] [Fig. 1] describes a set of coaxial vertical probes 120 according to one embodiment of the invention. The vertical probes 120 are described in connection with [Fig. 2], [Fig. 3] and [Fig. 4]. The vertical probes 120 are adapted to be included in a geothermal system 1 described in [Fig. 5] and [Fig. 6].
[0058] [Fig. 5] describes a geothermal system 1, comprising an energy production system 10 capable of heating a heat transfer fluid. The heat transfer fluid can circulate in a closed circuit to collect or inject energy from a subsoil. The energy production system 10 of this embodiment comprises a solar power plant. The solar power plant comprises solar thermal collectors for the production of heat, cooling and / or electrical energy.
[0059] [Fig. 6] describes a geothermal system 1, comprising an energy production system 10 capable of heating a heat transfer fluid. The heat transfer fluid can circulate in a closed circuit to extract or inject energy from a subsoil. The energy production system 10 of this embodiment uses fatal energy.
[0060] The geothermal system 1 comprises a system 11 for transforming thermal energy from the heat transfer fluid. The transformation system 11 comprises a heat pump, a refrigeration machine, and / or a turbine.
[0061] The geothermal system 1 comprises a geothermal energy storage system 12 described in [Fig. 2] and [Fig. 4]. The energy storage system 12 comprises a closed circuit for circulating the heat transfer fluid. The energy storage system 12 comprises a first heat transfer section connected to the energy production system 10, a second heat transfer section connected to the transformation system 11 and at least one vertical geothermal probe 120 arranged in a borehole made in a ground and capable of storing or extracting thermal energy from this ground. In the embodiment described in [Fig. 1], the energy storage system 12 comprises two probes 120 and in the embodiment described in [Fig. 5] and [Fig. 6], the energy storage system 12 comprises a plurality of vertical geothermal probes 120.
[0062] The first heat transfer section is a first member for circulating a heat transfer fluid heated by the energy production system 10 in the vertical geothermal probe 120 to store thermal energy in the ground S. The second heat transfer section is a second member for circulating a heat transfer fluid stored in the geothermal energy storage system 12 to the transformation system 11 to extract thermal energy from the ground S. The energy storage system 12 makes it possible to store heat by exploiting the thermal inertia of the subsoil S through the heat capacity of the elements composing the subsoil S in which the vertical geothermal probes 120 are installed.
[0063] The vertical geothermal probe 120 comprises a first cold portion 120.1 extending into a borehole and a second transfer portion 120.2 extending into the borehole while being arranged below the first cold portion 120.1.
[0064] The vertical geothermal probe 120 comprises a first tube 120.4 and a second tube 120.5 arranged coaxially around the first tube 120.4. The tubes together form the first 120.1 and second 120.2 portions of the vertical geothermal probe 120.
[0065] The geothermal energy storage system 12 comprises a thermal insulation member 120.3 extending into the borehole only at the first cold portion 120.1. The second transfer portion 120.2 without thermal insulation member 120.3 gives off its heat to the substrate surrounding it. The thermal insulation member 120.3 is inserted inside the second tube 120.5. The thermal insulation member 120.3 is mounted against an internal wall of the second tube 120.5 and at a distance from the first tube 120.4.
[0066] The internal volume of the first tube 120.4 defines an injection volume of the heat transfer fluid heated by the energy production system 10 and the volume formed between the first tube 120.4 and the second tube 120.5 defines a volume for transferring thermal energy to the ground S for its storage during a charging cycle. The volume formed between the first tube 120.4 and the second tube 120.5 defines a volume for transferring thermal energy from the ground S. The internal volume of the first tube 120.4 defines an extraction volume of the heat transfer fluid heated by the ground S to the transformation system 11 during a discharging cycle.
[0067] During a charging cycle, the injection temperature of the heat transfer fluid at the inlet of the probe 120 is between 90 and 250°C.
[0068] During a discharge cycle, the injection temperature of the heat transfer fluid at the inlet of the probe 120 is greater than 60°C and the temperature of the heat transfer fluid at the outlet of the probe 120 is greater than 90°C.
[0069] The geothermal system 1 comprises a system for controlling a charging and discharging cycle of the storage system 12, arranged to control the circulation of the heat transfer fluid in the closed circulation circuit from the first section to the geothermal probe 120 or from the geothermal probe 120 to the second section according to a charging or discharging instruction of the geothermal system 1.
[0070] The first tube 120.4 comprises a plurality of tube sections arranged one after the other and held two by two by a fixing element 120.6. The second tube 120.5 comprises a plurality of tube sections arranged the one after the other and held in pairs by a fixing element 120.6. The fixing elements 120.6 are advantageously clip fittings. The fixing elements 120.6 are watertight. The fixing elements 120.6 are pre-insulated. The use of a plurality of tubes held in pairs by fixing elements allows the use of a probe 120 of 1000 m depth.
[0071] The vertical geothermal probe 120 comprises a closure member 120.8 for closing the second tube 120.5. The closure member 120.8 is mounted on the second tube 120.5 at the lower end of the second transfer portion. The closure member 120.8 comprises a solid tube segment. The closure member 120.8 is sealed. The closure member 120.8 is mounted at a lower end of the second tube 120.5, in particular in the transfer portion.
[0072] The vertical geothermal probe 120 comprises an external heat exchange layer arranged between an internal wall of the borehole and an external wall of the second tube 120.5.
[0073] The vertical geothermal probe 120 comprises a filtering member 120.7 mounted on the first tube 120.4 at the lower end of the second transfer portion. The filtering member 120.7 comprises on the first tube 120.4, at the lower end of the second transfer portion, a perforated tube segment distributing the heat transfer fluid adapted for charging and discharging and the sum of the flow rates of each hole of which is equal to the flow rate of the heat transfer fluid. The filtering member 120.7 is arranged to allow the passage of the heat transfer fluid from the internal volume of the first tube 120.4 to the volume formed between the first tube 120.4 and the second tube 120.5, and vice versa.
[0074] The transformation system 11 directs the energy produced to the buildings to be supplied.
[0075] In the embodiment described in [Fig. 5], the closed circulation circuit of the energy storage system 12 comprises a plurality of vertical geothermal probes 120 connected in parallel and / or in series to a collector 13 connected to the first and second transfer sections. The collector 13 is arranged to distribute the heat transfer fluid to each of the geothermal probes. vertical 120. The collector 13 is arranged to distribute the heat transfer fluid to each of the vertical geothermal probes 120.
[0076] In the embodiment described in [Fig. 6], the closed circulation circuit of the energy storage system 12 comprises a plurality of vertical geothermal probes 120 connected in parallel and / or in series to a collector 13 connected to the first and second transfer sections. The collector 13 is arranged to distribute the heat transfer fluid to each of the vertical geothermal probes 120. The collector 13 is arranged to distribute the heat transfer fluid to each of the vertical geothermal probes 120.
[0077] The foregoing description clearly explains how the invention makes it possible to achieve the objectives it has set itself, namely to propose a geothermal system making it possible to combat global warming by eliminating the use of fossil fuels and reducing greenhouse gas emissions and protecting the environment in which the system is integrated while producing heat, and / or cooling and / or electrical energy, by proposing a geothermal system, comprising an energy production system capable of heating a heat transfer fluid; a system for transforming thermal energy from a heat transfer fluid;a geothermal energy storage system comprising at least one closed circuit for circulating a heat transfer fluid comprising at least one vertical geothermal probe comprising a first tube and a second tube arranged coaxially around said first tube, said probe being arranged in a borehole made in a ground and capable of storing or extracting thermal energy from this ground; a system for controlling a charge and discharge cycle of the storage system characterized in that the geothermal probe comprises a first cold portion and a second transfer portion arranged below the first cold portion and in that the geothermal energy storage system comprises a thermal insulation member inserted against a wall of the second tube extending into the borehole only at the level of the first cold portion.;
[0078] In any event, the invention cannot be limited to the embodiments specifically described in this document, and extends in particular to all means equivalents and any technically effective combination of these means. In particular, we may consider: The heat transfer fluid can be a liquid heat transfer fluid. The heat transfer fluid can be a gaseous heat transfer fluid. The energy production system may include a fatal energy recovery plant. In another embodiment, the energy production system may comprise any so-called renewable energy source and / or intermittent or continuous, local, carbon-free and renewable energy source. In another embodiment, the energy production system may include a renewable thermal energy source. In a different embodiment, the energy production system may comprise a source of recovery thermal energy greater than 70°, in particular greater than 90°. The first tube may be pre-insulated steel. The first tube may be evacuated. The first tube may not be evacuated. The second tube may be pre-insulated steel. The second tube may be evacuated. The second tube may not be evacuated. The fixing elements can be of the screwed and / or notched sleeve type.
Claims
Claims
1. Geothermal system (1), comprising: An energy production system (10) capable of heating a heat transfer fluid; A system for transforming (11) thermal energy from a heat transfer fluid; A geothermal energy storage system (12) comprising at least one closed circuit for circulating a heat transfer fluid comprising at least a first heat transfer section connected to the energy production system (10), a second heat transfer section connected to the transformation system (11) and at least one vertical geothermal probe (120) comprising a first tube (120.4) and a second tube (120.5) arranged coaxially around said first tube (120.4), said probe (120) being arranged in a borehole (F) made in a ground (S) and capable of storing or extracting thermal energy from this ground (S); A system for controlling a charge and discharge cycle of the storage system (12), arranged to control the circulation of the heat transfer fluid in the closed circulation circuit from the first section to the geothermal probe or from the geothermal probe to the second section according to a charge or discharge instruction of the geothermal system (1); Characterized in that the vertical geothermal probe (1) comprises a first cold portion (120.1) extending into the borehole (F) and a second transfer portion (120.2) extending into the borehole (F) while being arranged below the first cold portion (120.1) and in that the geothermal energy storage system (1) comprises a thermal insulation member (120.3) inserted against a wall of the second tube (120.5), extending into the borehole (F) only at the level of the first cold portion (120.1).
2. Geothermal system (1) according to claim 3, characterized in that the closed circulation circuit of the energy storage system (12) comprises a plurality of vertical geothermal probes (120) connected in parallel and / or in series to a collector (13) connected to the first and second transfer sections and arranged to distribute the heat transfer fluid to each of the vertical geothermal probes (120).
3. Geothermal system (1) according to one of the preceding claims, characterized in that the energy production system (10) comprises a solar power plant and / or an energy recovery plant.
4. Geothermal system (1) according to one of the preceding claims, characterized in that the vertical geothermal probe (120) comprises a first tube (120.4) and a second tube (120.5) arranged coaxially around the first tube (120.4), the tubes (120.4; 120.5) together forming said first (120.1) and second (120.2) portions of the vertical geothermal probe (120), the internal volume of the first tube (120.4) defining a volume for injecting the heat transfer fluid heated by the energy production system (10) and the volume formed between the first tube (120.4) and the second tube (120.5) defining a volume for transferring thermal energy to the ground (S) for its storage during a charging cycle; and the volume formed between the first tube (120.4) and the second tube (120.5) defining a volume of thermal energy transfer from the ground (S) and the internal volume of the first tube (120.4) defining an extraction volume of the heat transfer fluid heated by the ground (S) towards the transformation system during a discharge cycle.
5. Geothermal system (1) according to one of the preceding claims, characterized in that said vertical geothermal probe (120) comprises an external heat exchange layer arranged between an internal wall of the borehole (F) and an external wall of the second tube (120.5).
6. Geothermal system (1) according to one of claims 4 or 5, characterized in that the first tube (120.4) comprises a plurality of tube sections arranged one after the other and held two by two by a fixing element (120.6).
7. Geothermal system (1) according to one of claims 4 to 6, characterized in that said vertical geothermal probe (120) comprises a filtration member (120.7) mounted on the first tube (120.4) at the lower end of the second transfer portion (120.2).
8. Geothermal system (1) according to one of claims 4 to 7, characterized in that said vertical geothermal probe (120) comprises a closing member (120.8) of the second tube (120.5), mounted on the second tube (120.5) at the lower end of the second transfer portion (120.2).
9. Geothermal system (1) according to one of the preceding claims, characterized in that the heat transfer fluid comprises a liquid or gaseous fluid.
10. Geothermal system (1) according to one of the preceding claims, characterized in that the system (11) for transforming thermal energy from a heat transfer fluid comprises a heat pump, a refrigeration machine, and / or a turbine.