Carnot battery with simplified charging cycle via an ejector ensuring cold production

Abstract

Carnot battery with simplified charging cycle by an ejector ensuring cold production. The invention relates to a Carnot battery comprising a drive cycle for converting thermal energy into electricity and a simplified ejector-equipped refrigeration cycle (SERS) comprising a working fluid circulation refrigeration circuit comprising three branches arranged in parallel: a drive branch and a refrigeration branch, and a mixing branch on which is arranged an ejector for ensuring the mixing of the working fluid from the drive branch and the working fluid from the refrigeration branch, and the battery comprising a thermal energy storage module comprising a fluid for storing cold thermal energy and forming the source to be cooled for the refrigeration branch.The storage module is thermally connected to the condenser of the engine cycle, ensuring the transfer of cold thermal energy from the fluid stored in the energy storage module to the engine cycle. Figure for the abbreviation: Fig. 1,

Description

Title of the invention: Carnot battery with simplified charging cycle using an ejector to ensure cooling production. Technical field

[0001] The present invention relates to Carnot batteries and more particularly to those operating with a subcritical cycle.

[0002] It belongs to the technical fields corresponding on the one hand to electricity storage technologies and on the other hand to systems increasing the flexibility of thermal power plants.

[0003] Potential applications include electricity storage linked to a thermal power plant. Another related application is the addition of a Carnot battery to a thermal power plant. STATE OF THE ART

[0004] Carnot batteries (CBs) rely on storing electricity in the form of heat. When a CB stores electricity, it converts it into heat via a charging process and then stores the heat in a thermal storage module. This charging process can typically be an electrical resistance or a heat pump (HP), both of which are electricity-to-heat converters. When the battery is required to release the electricity it has previously stored, the energy stored in the thermal storage module is discharged using a motor cycle. This motor cycle is a converter symmetrical to the charging process, which, this time, converts heat into electricity. The motor cycle can typically be an organic or non-organic Rankine cycle (ORC) or a Brayton cycle. This type of CB is referred to as an isolated or "standalone" battery in the literature.

[0005] Carnot batteries offer several advantages: firstly, they provide a solution for large-scale electricity storage. Like all electricity storage technologies, Carnot batteries can also provide services to the grid, particularly in terms of stability and flexibility. Furthermore, they have few geographical constraints, as their installation requires neither a valley nor a cavern and does not generate any particular hazards in its immediate vicinity.

[0006] However, BCs suffer from several limitations to their development: this technology has relatively modest conversion efficiencies, on the order of 30% to 60% according to the literature for isolated BCs. Related to this modest efficiency, the economic viability of projects based on BCs is not always guaranteed. Finally, isolated BCs suffer from limited reactivity, inherent to the temperature rise time of the motor cycle and the adjacent pipes during the initiation of the discharge phase.

[0007] Battery cells can be integrated through different architectures into thermal power plants. Two concepts identified to date stand out: one is called coupled batteries (CBB) and the other called grafted batteries (GBB).

[0008] The concept of coupled Carnot batteries is based on an architecture comprising a thermal power plant coupled to a Carnot battery via the charging process and the thermal storage component. Thus, a portion of the power plant's heat flux is no longer directly converted into electricity by the engine cycle, but temporarily stored without any temperature increase. The charging cycle is used either to compensate for some of the storage losses or to increase the amount of stored thermal energy, but always at a uniform temperature between the storage and the power plant's heat source.

[0009] The main advantage of this coupling is the increased flexibility it provides to the power plant. Indeed, the plant operates continuously and, like many thermal power plants, is not easily controllable. This lack of flexibility, given the high variability of electricity demand, can cause grid stability problems. Thus, a coupled storage power plant (SPP) allows, during periods of grid tension, for a portion of the electricity production to be curtailed by diverting some of the heat flow to be stored in the storage power plant (SPP). Then, when the grid again requires increased electricity production, the SPP can be discharged via its engine cycle, which is shared with the thermal power plant. Therefore, during the discharge phase, the power plant will operate at its nominal capacity, but additional heat from the SPP will be discharged in parallel within the engine cycle.This additional heat discharge from the CCB will result in a surplus of electricity production compared to the power plant's nominal operating capacity. Thus, a CCB coupled to a power plant provides it with increased flexibility, manifesting as a better match between electricity production and demand, through demand response followed by surplus electricity production. In the case of CCBs, power modulation is therefore achieved by regulating the flow rate of the heat flux sent to the engine cycle.

[0010] Another important characteristic of DCBs is that their operation is correlated with that of the thermal power plant. Indeed, for the sharing of the engine cycle between the DCB and the power plant to be realistic, the additional discharge power provided by the DCB must be small compared to the power plant's nominal output. Thus, the DCB cannot operate alone. For the BCC to be able to charge and discharge, the thermal power plant must be in operation.

[0011] The other advantages of implementing this coupling lie primarily in the sharing of the power cycle. Indeed, this sharing firstly allows for a significant reduction in the costs of a DCB compared to an isolated DCB. Secondly, this sharing also allows for a significant increase in the DCB's responsiveness. In fact, unlike isolated DCBs, where the power plant operates continuously, the power cycle is always running. Thus, since the power cycle is always at operating temperature and always running, the effects related to the inertia of starting the power cycle no longer penalize the DCB, and therefore allow for a significant gain in responsiveness. It can also be noted that DCBs, thanks to their improved responsiveness, allow for load and frequency tracking, in addition to the other classic services that storage technologies are capable of providing to the grid.

[0012] The operation and architecture of BCGs are similar to those of BCCs. Their differentiating characteristic lies in the method of utilizing the heat flow from the power plant. In the case of BCCs, the power plant's heat flow is directly integrated into the storage module, whereas for BCGs, it is utilized in the charging process.

[0013] Thus, the diverted heat from the power plant is utilized during the charging of the combined cycle heat exchanger (CCH) and is raised to a higher temperature than that of the power plant before being stored. During discharge, the heat at a higher enthalpy is used in the engine cycle and therefore increases the enthalpy of the power plant's nominal heat flow. During the discharge phase, since the engine cycle is powered by a higher enthalpy heat flow, the net output of the cycle is increased. Thus, when the grid is under load and it is necessary to store electricity, a charging phase of the CCH will be carried out, which consumes electricity. This charging phase will allow the storage of heat at a higher temperature, which will then be discharged when the grid again needs electricity, thereby increasing the net output of the power plant's engine cycle.Conversely, if the BCG has a cold storage, the temperature reached by the charging cycle will be lower than that of the cold source of the motor cycle.

[0014] Here again, the thermal power plant is in continuous operation. Thus, the major difference between BCCs and BCGs is that the production modulation of the thermal power plant is not based on a modulation of the flow rate through the engine cycle, as in the case of BCCs, but on a modulation of the temperature of the flow through the engine cycle for BCGs. This temperature-based, rather than flow-based, control strategy allows for a different constraint to be placed on the turbine, which could be interesting. Another important characteristic of BCGs is that they cannot operate independently of the power plant, as with BCCs.

[0015] The advantages of implementing a BCG are quite similar to those of a BCC. Indeed, for the same reasons as a BCC, a BCG has much better responsiveness than isolated batteries, thus enabling charge or frequency monitoring, for example. Cost reduction is also possible thanks to the sharing of the motor cycle. Finally, BCGs are capable of achieving better storage efficiencies than conventional batteries, without resorting to additional external heat sources.

[0016] Patent document FR3060190B1 is also known, describing a BC architecture that increases the flexibility of a Brayton cycle. The BCG comprises a cold water storage tank supplied by a refrigeration machine. Discharge of this BCG is ensured by two heat exchangers connected directly to the working fluid circuit of the Brayton cycle.

[0017] These various solutions are well suited to operation under supercritical and transcritical cycles. However, this implies significant development and infrastructure costs to ensure that the components can be implemented in these demanding cycles, which require high temperatures and pressures.

[0018] Now, currently with the growing desire to optimize the recovery of waste heat from many industrial processes with temperatures less than or equal to 300°C, there is therefore a need to propose a solution to allow the operation of Carnot batteries and in particular Grafted Carnot Batteries (BCG) or Coupled Carnot Batteries (BCC) with subcritical cycles at low temperatures, i.e. less than or possibly equal to 300°C. SUMMARY

[0019] To achieve this objective, according to one embodiment, a Carnot battery is provided comprising a power cycle for converting thermal energy into electricity comprising a working fluid circulation circuit, an evaporator providing heat exchange with a hot source, a turbine, a condenser providing heat exchange with a cold source, and a pump, the circulating power circuit being configured to provide successive fluid connections to the evaporator, turbine, condenser, pump, and then back to the evaporator, characterized in that it comprises an ejector refrigeration cycle (SERS) comprising a working fluid circulation refrigeration circuit comprising three branches arranged in parallel: a drive branch on which are arranged the pump and the evaporator of the motor cycle designed to ensure heat exchange between a heat source and the working fluid, and a refrigeration branch arranged in a bypass of the engine cycle extending from downstream of the engine cycle condenser upstream of the engine cycle pump, and on which are arranged an expansion valve and an evaporator intended to extract heat from a source to be cooled, and a mixing branch on which are arranged an ejector intended to ensure the mixing of the working fluid from the drive branch and the working fluid from the refrigeration branch, and the condenser of the engine cycle intended to ensure heat exchange between a cold source and the mixed working fluid from the ejector, the ejector comprising a first inlet fluidically connected to the drive branch downstream of the evaporator of the engine cycle, a second inlet fluidly connected to the refrigeration loop downstream of the evaporator and an outlet fluidly connected to the condenser of the engine cycle and a thermal energy storage module comprising a fluid intended to store cold thermal energy and forming the source to be cooled of the evaporator of the refrigeration branch, the storage module being thermally connected to the condenser of the engine cycle ensuring the thermal transfer of the cold thermal energy from the fluid stored in the energy storage module to the engine cycle.

[0020] The Carnot battery according to the invention allows a cold storage module to be charged by supplying it via an ejector during the charging phase. The Carnot battery according to the invention combines a motor cycle with a storage module and a refrigeration cycle with an ejector.

[0021] The battery according to the invention makes it possible to simplify the Carnot battery charging process without having to use a rotating machine during compression.

[0022] One of the advantages of the invention is therefore to replace the compressor of a refrigeration machine with an ejector, which is an inert component and thus more reliable, more durable, and less expensive. Furthermore, using an ejector as a means of compression for producing cold eliminates the need for a separate electrical line to power the compressor, which is a costly operation, both in terms of installation and the subscription required to access the grid. In addition, the invention allows the use of a single fluid between the motor cycle and the refrigeration cycle. The ejector facilitates charging, which simplifies the operation and maintenance of the system.

[0023] Storing electrical energy in the form of cold storage also reduces losses during the storage phase, thus improving the profitability of subcritical BCGs.

[0024] According to one possibility, the Carnot battery includes an intermediate circuit ensuring the heat transfer of cold thermal energy from the fluid stored in the energy storage module and the condenser. The intermediate circuit includes a discharge heat exchanger ensuring the heat transfer of cold thermal energy from the fluid to the cold source supplying the condenser of the engine cycle. This possibility is particularly useful for subcritical cycles.

[0025] The Carnot battery according to the invention allows for the optimal discharge of stored cold in the case of subcritical cycles. Indeed, the presence of the intermediate circuit with the discharge exchanger, ensuring indirect discharge of the stored cold to the engine cycle, expands the operating range of Carnot batteries, particularly those grafted onto subcritical cycles. The Carnot battery according to the invention thus offers ease of implementation thanks to the technological maturity of the components for the low temperatures conducive to subcritical cycles. Furthermore, the infrastructure costs of grafted subcritical Carnot batteries are therefore lower, with significant potential for widespread adoption.

[0026] By introducing the intermediate circuit allowing discharge, it is possible not only to play on the degree of subcooling, but also to play on the low pressure of the engine cycle, which leads to much higher restitution ratios and suggests an economic reality for the system.

[0027] Indeed, the architectures adapted to transcritical and supercritical cycles known today in the literature do not allow a reduction in the low pressure of the engine cycle. However, in subcritical operation, the direct discharge of the BCG via a heat exchanger in series with the engine cycle evaporator leads only to an increase in subcooling.

[0028] However, an increase in subcooling does not generate any increase in turbine performance and therefore does not lead to an increase in electrical production for subcritical cycles.

[0029] The advantage of the present invention is therefore to overcome the problem of adding only subcooling to the fluid by the BCG.

[0030] The invention thus makes it possible to improve the controllability and flexibility of thermal power plants. The storage linked to the power plant provides increased stability for the grid, but also allows the operator to perform load following and frequency tracking, as well as energy arbitrage.

[0031] Following another aspect, the invention relates to a method for producing electrical energy by a Carnot battery as described below, comprising a charging step comprising Heat exchange in the engine cycle evaporator between the hot source and the working fluid ensures the evaporation of the working fluid. a circulation of at least part of a working fluid flow in the turbine of the engine cycle ensuring the expansion of the working fluid from the evaporator and the production of electricity by an associated generator, circulation of at least a portion of a working fluid flow in the ejector from the turbine or evaporator of the engine cycle, a mixture in the ejector of the working fluid from the drive branch and the working fluid from the refrigeration branch, a diversion of at least part of the working fluid flow between the downstream side of the condenser and the upstream side of the pump towards the refrigeration branch, the storage of cold thermal energy in the storage module by heat exchange in the evaporator of the refrigeration branch between the working fluid and the storage fluid. BRIEF DESCRIPTION OF THE FIGURES

[0032] The aims, objects, features and advantages of the invention will become clearer from the detailed description of an embodiment thereof, which is illustrated by the following accompanying drawings in which:

[0033] [Fig. 1] The [Fig. 1] represents a schematic diagram of the Carnot battery according to the invention with the turbine and the ejector arranged in parallel.

[0034] [Fig.2] Fig.2 represents a schematic diagram of the Carnot battery during a stationary phase.

[0035] [Fig.3] The [Fig.3] represents a schematic diagram of the Carnot battery during a discharge phase.

[0036] [Fig.4] [Fig.4] represents a schematic diagram of the Carnot battery during a charging phase.

[0037] [Fig.5] [Fig.5] represents a diagram of another alternative possibility to [Fig.1] with the turbine and the ejector arranged in series.

[0038] [Fig.6] [Fig.6] represents a diagram of another alternative possibility to [Fig.1] without an intermediate discharge circuit.

[0039] The drawings are given by way of example and are not limiting of the invention. They constitute schematic representations of principle intended to facilitate understanding of the invention and are not necessarily to scale with practical applications. DETAILED DESCRIPTION

[0040] Before proceeding to a detailed review of embodiments of the invention, optional features that may be used in combination or alternatively are listed below:

[0041] According to one example, the turbine (201) is arranged on the drive branch downstream of the evaporator (202) of the engine cycle (200) and upstream of the ejector (101).

[0042] According to one example, the turbine (201) is arranged on a bypass pipe arranged between the downstream of the evaporator (202) of the engine cycle (200) and the downstream of the ejector (101) upstream of the condenser (204) on the mixing branch.

[0043] According to one example, the Carnot battery includes an intermediate circuit (1) ensuring the heat transfer of cold thermal energy from the fluid stored in the cold thermal energy storage module (3) and the condenser (204) of the engine cycle (200), the intermediate circuit (1) includes a discharge heat exchanger (2) ensuring the heat transfer of cold thermal energy from the fluid to the cold source (5) supplying the condenser (204) of the engine cycle (200).

[0044] According to one example, the Carnot battery includes a first recuperator (203) arranged at the interface of the driving branch and the mixing branch between the downstream of the ejector (101) and the downstream of the pump (205).

[0045] According to one example, the Carnot battery includes a second recuperator (103) arranged on the refrigeration branch between the downstream of the condenser (204) of the engine cycle (200) and the downstream of the evaporator (104) of the refrigeration branch.

[0046] According to one example, the electrical energy production process includes a cold thermal energy discharge step comprising, a release of the fluid from the storage module a heat exchange in the discharge heat exchanger (2) between the fluid released from the thermal energy storage module (3) and a cold source (5) to lower the temperature of the cold source (5), a heat exchange in the condenser (204) of the engine cycle (200) between the cooled cold source and an engine fluid circulating in the engine cycle (200) allowing the condensation of the engine fluid.

[0047] According to one example, the process of producing electrical energy includes a heat exchange in the evaporator (202) of the engine cycle (200) between the heat source (6) and the engine fluid to ensure the evaporation of the engine fluid, an expansion of the engine fluid from the evaporator (204) in the turbine (201) of the engine cycle allowing the production of electricity by an associated generator (206).

[0048] According to one example, the electrical energy production process includes a stationary operating stage comprising a heat exchange in the evaporator (202) of the engine cycle (200) between the heat source (6) and the engine fluid to ensure the evaporation of the engine fluid, an expansion of the engine fluid from the evaporator (202) of the engine cycle (200) in the turbine (201) of the engine cycle (200) allowing the production of electricity by an associated generator (206). a heat exchange in the condenser (204) of the engine cycle (200) between the cold source (5) and the engine fluid to ensure the condensation of the engine fluid.

[0049] The upstream and downstream, the inlet, the outlet, at a given point are taken with reference to the direction of fluid flow.

[0050] A parameter "approximately equal to / greater than / less than" or "of the order of" a given value means that this parameter is equal to / greater than / less than the given value, to within 10% or even 5% of that value.

[0051] For the purposes of this disclosure, the expression "A and / or B" means (A), (B) or (A and B). For the purposes of this disclosure, the expression "A, B and / or C" means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B and C).

[0052] By supercritical, it is understood that the Carnot battery according to the invention operates at pressure and temperature levels above the critical point of the circulating working fluid.

[0053] Transcritical means that the Carnot battery according to the invention operates at pressure and temperature levels above and below the critical point of the circulating working fluid.

[0054] By subcritical, it is understood that the Carnot battery according to the invention operates at pressure and temperature levels below the critical point of the circulating working fluid.

[0055] Fluidically connected or in fluidic connection means when a line provides a connection by or in which a fluid flows.

[0056] In the present description, the expression "A fluidly connected to B" is synonymous with "A is in fluidic connection with B" and does not necessarily mean that there is no component between A and B. The expressions "arranged on" or "on" are synonymous with "fluidly connected to".

[0057] The expression "A fluidically connected to B" or "A fluidly connected to B" is synonymous with "A is in fluidic connection with B" and does not necessarily mean that there is no component between A and B. Thus, these expressions refer to a fluidic connection between two elements, this connection being either direct or indirect. This means that it is possible that between a first element and a second element that are fluidically connected, a fluid path exists through one or more conduits or connections, possibly including an additional component.

[0058] Conversely, the term "fluidically connected directly" refers to a direct fluidic connection between two elements. This means that between a first element and a second element that are fluidly connected directly, no no other element is present, other than one or more conduits / connections / channels.

[0059] Hot, cold, cooled means a relative temperature with respect to another point in the system.

[0060] The terms "first", "second" and "third", "additional", etc. are used simply as labels, and are not intended to impose numerical requirements on their objects.

[0061] The invention consists of a Carnot battery grafted to a thermal power plant for electricity production, based on a motor cycle that advantageously operates in subcritical mode.

[0062] The Carnot battery according to the invention comprises a thermal power plant for generating electricity intended to convert thermal energy into electricity. In this application, the terms power plant, generating plant, and thermal power plant are used interchangeably to define the thermal power plant for generating electricity.

[0063] The thermal power plant can be of different types. The thermal power plant includes a heat source 6 which can be of various kinds, for example, geothermal, biomass, fossil fuels, solar energy, nuclear, or waste heat. The thermal power plant includes a drive cycle 200 which transforms the heat source 6 into electrical energy. For example, the heat source 6 has a temperature between 80 and 800°C.

[0064] The Carnot battery thus comprises a drive cycle 200 for converting thermal energy from a hot source 6 into electricity. The drive cycle 200 comprises at least one evaporator 202, one turbine 201 and one condenser 204.

[0065] The motor cycle 200 is for example a Brayton cycle or a Rankine cycle or an organic Rankine cycle.

[0066] The engine cycle 200 includes an engine fluid circuit receiving an engine fluid and intended to connect the various components of the engine cycle 200 via fluid flow. The engine fluid circuit is a circulation loop comprising fluid connections and components. The engine fluid circuit is a closed loop.

[0067] The evaporator 202 is configured to ensure heat exchange between the engine cycle 200 and the hot source 6. The function of the evaporator 202 is to ensure the evaporation of the engine fluid through the supply of hot thermal energy by the hot source 6.

[0068] The turbine 201 of the engine cycle is configured to ensure the expansion of the working fluid to drive the turbine 201. Advantageously, the turbine 201 is associated with a generator 206. The generator 206 is set in motion by turbine 201 during the expansion of the working fluid and thus ensures the production of electricity.

[0069] By way of example, turbine 201 is an axial turbomachine. The present invention remains functional for any type of expansion turbine, whether axial, centripetal or hybrid, a positive displacement machine of the scroll, piston, screw type, etc. type.

[0070] The condenser 204 of the engine cycle is configured to ensure heat exchange between the engine cycle and a cold source 5. The condenser 204 has the function of ensuring the condensation of the engine fluid through cooling achieved by the supply of cold thermal energy from the cold source 5.

[0071] Advantageously, the engine cycle includes a pump 205 intended to move the engine fluid in the fluidic circuit of the engine cycle.

[0072] According to a preferred possibility, the fluidic circuit of the motor cycle 200 ensures the successive fluidic connection of the evaporator 202 connected fluidly, preferably directly, to the turbine 201, then the turbine 201 is connected fluidly to the condenser 204, preferably via the first recuperator 203, then the condenser 204 is connected fluidly, preferably directly, to the pump 205, then the pump 205 is connected fluidly to the evaporator 202, preferably via the first recuperator of 203.

[0073] According to the illustrated embodiment, the engine cycle 200 is an organic Rankine cycle. As such, the engine fluid circulating in the engine cycle 200 is an organic fluid such as Novec649.

[0074] According to the invention, the Carnot battery comprises an ejector refrigeration cycle also called a simple ejector refrigeration cycle (SERS) advantageously comprising a pump 205, a generator 202, an expansion valve 104, an evaporator 102, a condenser 204 and an ejector 101.

[0075] An ejector 101 is an inert thermodynamic component that allows the compression and mixing of a flow from a second flow of higher pressure. The ejector 101 comprises a first inlet of the fluid called the primary fluid or driving fluid or high-pressure fluid, a second inlet of the fluid called the secondary fluid or working fluid or refrigerant or low-pressure fluid, and an outlet of the mixed fluid.

[0076] According to the invention, the ejector refrigeration cycle includes the pump 205 of the motor cycle 200, the generator is the evaporator 202 of the motor cycle 200, the condenser is the condenser 204 of the motor cycle 200.

[0077] Advantageously, the refrigeration cycle includes a refrigeration fluid circuit enabling the fluid connection of the different elements as well as the circulation of a working fluid.

[0078] The refrigeration fluid circuit is a circulation loop comprising fluid connections and components. The refrigeration fluid circuit is a closed loop.

[0079] The refrigeration fluid circuit and the engine fluid circuit are at least partially common.

[0080] The working fluid of the refrigeration cycle and the driving fluid of the engine cycle are the same fluid. It may be designated differently depending on the operating phases of the Carnot battery; in the following description, the terms working fluid and driving fluid are used interchangeably. The working fluid, like the driving fluid, is therefore an organic fluid such as Novec649.

[0081] The fluidic circuit includes a drive branch on which the pump 205 and the evaporator 202 of the engine cycle 200 are arranged. The drive branch extends from the inlet of the pump 205 to the first working fluid inlet of the ejector 101. Advantageously, the drive branch operates at high pressure. The working fluid circulating in this drive branch is preferentially compressed by the pump 205. The pressure in the branches is highly dependent on the working fluid. For example, using Novec649 as the working fluid, the pressure in the drive branch is approximately 6.366 for a hot source temperature of 130°C.

[0082] The refrigeration fluid circuit comprises a refrigeration branch on which the expansion valve 104 and the evaporator 102 are arranged. The refrigeration branch extends from the outlet of the condenser 204 to the second working fluid inlet of the ejector 101. Advantageously, the refrigeration branch operates at low pressure. The working fluid circulating in this refrigeration branch is preferentially expanded by the expansion valve 104. Then, the expanded working fluid from the expansion valve 104 enters the evaporator 102. In the evaporator 102, the expanded working fluid is vaporized by heat exchange with a source to be cooled. The source to be cooled is advantageously a fluid contained in a storage module 3. This exchange in the evaporator 102 allows cold thermal energy to be stored in the storage module 3. The working fluid, after cooling the storage module 3 by evaporating, is therefore in a gaseous state and at low pressure.In order for this working fluid to be reintegrated into the engine cycle 200, it is compressed in the ejector 101, driven by the high-pressure engine fluid from the engine cycle 200.

[0083] According to an advantageous embodiment, the refrigeration branch comprises a second recuperator 103 arranged between the upstream of the expansion valve 104 and the downstream of the evaporator 102. The 2nd recuperator thus makes it possible to cool the working fluid entering the refrigeration branch, i.e. upstream of the expansion valve 104, by transferring thermal energy to the working fluid leaving the refrigeration branch, i.e. at the outlet of the evaporator 102.

[0084] The fluid circuit includes a mixing branch on which the ejector 101 and the condenser 204 are arranged. The mixing branch extends from the first and second inlets of the ejector 101 to the outlet of the condenser 204. Advantageously, the mixing branch operates at an intermediate pressure. The working fluid circulating in this mixing branch is a mixture of the motive fluid from the motive branch and the working fluid from the refrigeration branch. By way of example, the pressure in the mixing branch is approximately 1.012 bar in the case of a cold source at 13°C.

[0085] According to a first embodiment, as illustrated in Figures 1 to 4 and 6, the turbine 201 and the ejector 101 are arranged in parallel downstream of the evaporator 202. The working fluid flow from the evaporator 202 is advantageously distributed between the turbine 201 and the ejector 101. The working fluid flow having circulated in the turbine 201 and the working fluid flow having circulated in the ejector are joined upstream of the condenser 204 and possibly upstream of the first recuperator 203 if it is present.

[0086] According to a 2nd embodiment, as illustrated in [Fig.5], the turbine and the ejector 101 are arranged in series downstream of the evaporator 202. The working fluid flow from the evaporator 202 circulates in the turbine 201 and then in the ejector 101.

[0087] According to an advantageous embodiment, the Carnot battery comprises a first recuperator 203. The first recuperator 203 advantageously forms part of the ejector refrigeration cycle, being arranged at the interface between the mixing branch and the driving branch. Preferably, the first recuperator 203 is arranged at the interface between the fluid connection between the pump 205 and the evaporator 202 and the fluid connection between the outlet of the ejector 101, and according to the embodiment of the outlet of the turbine 201, and the inlet of the condenser 104. The first recuperator is intended to ensure a heat exchange between the mixing fluid at the outlet of the ejector 101, and possibly the working fluid at the outlet of the turbine 201 and the working fluid at the outlet of the pump 205 allowing a preheating of the working fluid before its entry into the evaporator 202 and a cooling of the working fluid before its entry into the condenser 204.

[0088] Preferably, the Carnot battery includes bypass fluid connections N, M to ensure circulation of the fluid in bypass of the first recuperator 203.

[0089] As illustrated in all the figures, the three branches of the fluidic circuit are arranged in parallel with each other.

[0090] Preferably, the refrigeration fluid circuit comprises a drive loop, or primary loop, including the drive branch and the mixing branch. The drive loop includes the ejector 101, the condenser 204, the expansion valve 104, and the evaporator 202 of the drive cycle 200. The working fluid exits in liquid form from the outlet of the condenser 204 and is herein referred to as the drive fluid or working fluid. The liquid drive fluid is compressed by the pump 205 arranged on the drive branch to be sent to the evaporator 202. In the evaporator 202, the compressed liquid drive fluid is vaporized, advantageously by heat transfer from a hot source 6. At the outlet of the evaporator 202, the drive fluid in the form of compressed vapor, preferably at high pressure, enters the ejector 101 through the primary fluid inlet. Ejector 101 is configured to create acceleration of the engine fluid.The working fluid carries the vapor from the refrigeration branch, thus mixing the working fluid and the working fluid. At the outlet of the ejector 101, the mixed fluid, in vapor form, enters the condenser 204 to be condensed.

[0091] Preferably, the refrigeration fluid circuit comprises a refrigeration loop, or secondary loop, including the refrigeration branch and the mixing branch. The refrigeration loop includes the ejector 101, the condenser 204, the expansion valve 104, and the evaporator 102. The working fluid exits the condenser 204 in liquid form and is herein referred to as the refrigeration fluid or secondary fluid. The liquid refrigeration fluid undergoes a preferably isenthalpic expansion through the expansion valve 104 before being routed to the evaporator 102 for cooling. In the evaporator 103, the refrigeration working fluid is evaporated, recovering thermal energy from a source to be cooled. Preferably, the source to be cooled is the fluid in the storage module 3.At the outlet of the evaporator 103, the refrigerant working fluid is in a preferably low-pressure vapor state which is drawn by the working fluid into the ejector 101 through the secondary fluid inlet.

[0092] The working fluid which is sent to the refrigeration branch corresponds to the working fluid which can be carried by the ejector and therefore which is not sucked up by the pump 205.

[0093] The advantage of this simple ejector refrigeration cycle is to replace the work consumed by a compressor with much less work consumed by the pump 205, and with heat supplied via the evaporator 202 preferably at medium or high temperature.

[0094] According to the invention, the Carnot battery comprises a thermal storage module 3 including a fluid for storing cold thermal energy, advantageously produced by the ejector refrigeration cycle. The thermal storage module 3 is for example a fluid reservoir, advantageously thermally insulated from the environment.

[0095] As a preferred example, the refrigerant is glycol water. As an example, the refrigerant stored in the thermal storage module is at a temperature between -50°C and 50°C.

[0096] According to an unillustrated possibility, a compressor can be connected in parallel with the ejector 101 to provide assisted compression. This compressor, necessarily small in size, can assist the compression provided by the ejector 101 when the instantaneous cooling demand is significant. The compressor can operate in conjunction with the ejector 101 if an electrical flux is generated and needs to be stored in situ, or in a backup capacity to increase the operating range of the BCG.

[0097] According to an embodiment illustrated in Figures 1 to 5, the Carnot battery includes an intermediate circuit 1 ensuring the heat transfer of cold thermal energy from the fluid stored in the energy storage module 3 to the engine cycle 200. The intermediate circuit 1, called the intermediate discharge circuit, includes a discharge heat exchanger 2 ensuring the heat transfer between the fluid and a cold source 5 supplying the condenser 204 of the engine cycle 200.

[0098] Preferably, the intermediate circuit 1 includes a pump 4 intended to circulate the fluid between the storage module 3 and the discharge heat exchanger 2.

[0099] The architecture of the Carnot battery according to the invention makes it possible to optimize the discharge phase. Indeed, after having been previously charged, the storage module 3 is discharged via the intermediate circuit 1 on the cold source circuit 5.

[0100] Indeed, the presence of intermediate circuit 1 ensures optimal discharge of the Carnot battery, particularly for subcritical cycles.

[0101] According to another embodiment illustrated in [Fig. 6], the Carnot battery comprises an additional heat exchanger 20 arranged downstream of the condenser 204 and ensuring heat exchange between the fluid in the storage module and the working fluid circulating at the outlet of the condenser 204. The condenser 204 is supplied by a cold source 5, allowing initial cooling of the working fluid circulating in the condenser 104. The cooled working fluid then circulates in the additional heat exchanger 20, supplied by the refrigerant 3, allowing further cooling of the latter. This embodiment is particularly used in transcritical or supercritical cycles that do not require an intermediate circuit.

[0102] The cold source 5 is, for example, water from a water network, water from a river, etc. Preferably, the temperature of the cold source is between -50°C and 50°C.

[0103] According to one aspect, the Carnot battery comprises a control module including a plurality of valves for controlling the circulation of the working fluid in the fluidic circuits and a plurality of sensors for measuring predefined parameters on the fluidic circuits. The operation of the Carnot battery includes measuring predefined parameters on the fluidic circuits by sensors, comparing the measurements with predefined values, and initiating the different operating phases of the battery.

[0104] The architecture of a Carnot battery according to an example of the invention as illustrated in [Fig.1] is detailed below.

[0105] At the engine cycle 200, the hot source 6 is fluidically connected to the evaporator 202 of the engine cycle 200. The hot source 6 is fluidly connected, preferably directly, to the inlet of the hot source of the evaporator 202 by a fluid connection F. An outlet of the hot source of the evaporator 202 is fluidly connected to the outlet of the hot source 6 by a fluid connection G. Advantageously, the pump 11 is arranged on the fluid connection G.

[0106] At the engine cycle 200, the evaporator 202 includes an engine fluid inlet and outlet. The engine fluid outlet of the evaporator 202 is fluidically connected, preferably directly, to the turbine inlet 201 by a fluid connection H. The engine fluid inlet of the evaporator 202 is fluidly connected to a second outlet of the recuperator 203, if present, by the fluid connection L, otherwise to the pump 5 by the fluid connections K, M, L, otherwise to the condenser 204.

[0107] According to the first embodiment, the outlet of the motive fluid of the evaporator 202 is fluidically connected, by the fluidic connection H to a fluidic connection O supplying the turbine 201, preferably directly, and in parallel to a fluidic connection P supplying the primary inlet of the ejector 101.

[0108] The turbine 201 includes an inlet and an outlet of motive fluid. The outlet of motive fluid of the turbine 201 is fluidically connected to the inlet of the condenser 204, preferably the outlet of the turbine 201 is fluidically connected directly to a first inlet of the recuperator 203 by the fluid connections I, R, a first outlet of the recuperator 203 being fluidically connected directly to the inlet of motive fluid of the condenser 204 by the fluid connection J.

[0109] The ejector 101 includes a mixed fluid outlet. The outlet of the ejector 101 is fluidically connected to the inlet of the condenser 204; preferably, the outlet of the ejector 101 is fluidly connected directly to a first inlet of the recuperator 203 via fluid connections Q, R, a first outlet of the recuperator 203 being fluidically connected directly to the engine fluid inlet of the condenser 204 by the fluidic connection J.

[0110] According to the second embodiment, the outlet of the motive fluid from the evaporator 202 is fluidically connected via the fluid connection H to the inlet of the turbine 201, preferably directly. The outlet of the turbine 201 is connected via a fluid connection P' to the primary inlet of the ejector 101.

[0111] The ejector 101 includes a mixed fluid outlet. The outlet of the ejector 101 is fluidically connected to the inlet of the condenser 204, preferably the outlet of the ejector 101 is fluidly connected directly to a first inlet of the recuperator 203 by the fluid connections Q, R, a first outlet of the recuperator 203 being fluidly connected directly to the driving fluid inlet of the condenser 204 by the fluid connection J.

[0112] The condenser 204 includes an inlet and an outlet for the motive fluid. The motive fluid outlet of the condenser 204 is fluidically connected to a second inlet of the recuperator 203 by the fluid connection K. Advantageously, the pump 205 is arranged on the fluid connection K, advantageously downstream of the condenser 204 and upstream of the recuperator 203, if it is present, or otherwise upstream of the evaporator 202.

[0113] The condenser 204 includes a cold source inlet 5 fluidically connected to the cold source inlet in the Carnot battery.

[0114] According to one embodiment, at the intermediate circuit 1, the discharge heat exchanger 2 includes a cold source inlet and outlet 5, the cold source inlet of the discharge exchanger 2 is connected to the fluidic connection C allowing the arrival of the cold source in the Carnot battery, the cold source outlet of the discharge exchanger 2 is fluidically connected to the cold source inlet of the condenser 204 by the fluidic connection D, preferably directly.

[0115] The condenser 204 includes a cold source outlet fluidly connected to the cold source outlet out of the Carnot battery by the fluidic connection E.

[0116] The storage module 3 includes a stored fluid outlet fluidically connected to the refrigerant inlet of the discharge heat exchanger 2 by the fluid connection A. Advantageously, a pump 4 is arranged on the fluid connection A. The discharge heat exchanger 2 includes a fluid outlet fluidically connected to the inlet of the storage module 3 by the fluid connection B.

[0117] According to another embodiment, the Carnot battery comprises an additional heat exchanger 20 arranged downstream of the evaporator 104 on the fluid connection K. The outlet of the condenser 204 is fluidly connected to the inlet of the additional heat exchanger 20 by the fluid connection K'. The outlet of the additional heat exchanger 20 it is connected by the fluidic connection K' to the pump 205.

[0118] The storage module 3 includes a stored fluid outlet fluidically connected to the refrigerant inlet of the additional heat exchanger 20 by the fluid connection A. Advantageously, a pump 4 is arranged on the fluid connection A. The additional heat exchanger 20 includes a fluid outlet fluidly connected to the inlet of the storage module 3 by the fluid connection B.

[0119] The refrigeration branch begins with the fluid connection S extending between the fluid connection K and the evaporator 102. Advantageously, the second heat exchanger 103 and then the expansion valve 104 are arranged on the fluid connection S. The evaporator 102 includes an inlet connected to the fluid connection S and an outlet connected to the fluid connection T. The fluid connection T extends between the evaporator 102 and the secondary inlet of the ejector 101. Advantageously, the second heat exchanger 103 is arranged on the fluid connection T.

[0120] The Carnot battery according to the invention operates in 3 phases, including a stationary phase corresponding to the operation of transforming thermal energy into electrical energy, a charging phase corresponding to the operation of storing thermal energy and a discharging phase corresponding to the operation of releasing thermal energy.

[0121] In stationary phase, the Carnot battery according to the invention operates as illustrated in [Fig.2] detailed below.

[0122] The hot source 6, the engine cycle 200, and the cold source supply to the condenser 204 are active in the steady-state phase. Active means that fluid circulation is occurring. In the steady-state phase, the ejector 101, the refrigeration branch, and the intermediate circuit 1, which provides heat exchange between the storage module 3 and the engine cycle 200, are not active; that is, there is no fluid circulation. Advantageously, in this steady-state phase, the Carnot battery operates with only the engine cycle 200 activated, without the refrigeration cycle activated by the ejector. Advantageously, the first heat exchanger 203 is not active.

[0123] The stationary phase will be described below from an operational point of view.

[0124] The hot source 6 supplies the evaporator 202 of the motor cycle 200.

[0125] The hot source 6 enters the evaporator 202 at a temperature higher than its temperature at the outlet of the evaporator 202. The hot source 6 transfers its thermal energy to the engine cycle 200 through the evaporator 202. The engine cycle 200 enables the production of electrical energy by its turbine 201 associated with the generator 206. The condenser 204 is supplied by the cold source 5 from the environment. and which is neither powered nor cooled by the storage module. Ejector 1 is not operating; there is no cold production or cold storage in storage module 3. There is no cold release from the storage module. The stationary phase is an operating mode corresponding to a simple energy conversion.

[0126] In discharge phase, the Carnot battery according to the invention is illustrated in [Fig.3] detailed below.

[0127] The hot source 6, the motor cycle 200, the intermediate circuit 1, and the cold source supply to the condenser 204 are active during the discharge phase. Active means that fluid circulation is occurring. The ejector 101, the refrigeration branch, and more generally the ejector refrigeration cycle are not active; that is, there is no fluid circulation. Advantageously, the first recuperator 203 is not active.

[0128] The discharge phase of the Carnot battery is intended for the transmission of the previously stored cold to the engine cycle.

[0129] In discharge phase, the operation of the Carnot battery according to the invention is identical to the operation in stationary phase with the addition of the operation of the discharge of the storage module 3 either by the intermediate circuit 1, or by the additional heat exchanger which allows the release of the cold thermal energy stored in the storage module 3 to the engine cycle 200.

[0130] According to the embodiment illustrated in [Fig.3] comprising the intermediate circuit 1, the fluid stored in the storage module 3 is released to the discharge heat exchanger 2 which allows the transfer of thermal energy from the stored fluid to the cold source 5, which then supplies the condenser 204 of the motor cycle 200. The fluid returns to the storage module 3 at a temperature higher than that at which it left.

[0131] Thus, the discharge exchanger 2, via sensible heat transfer only, lowers the temperature of the cold source 5 of the engine cycle 200. The cold source 5 therefore enters the condenser 204 of the engine cycle at a lower temperature than during the stationary, also called nominal, operation of the Carnot battery. The temperature of the cold source 5 entering the condenser 204 results from the supply of cooling from the storage module 3 at the nominal heat flux of the cold source 5. Thus, since the profile of the cold source 5 at the condenser 204 is lower, this allows for a lower condensing pressure of the engine fluid than during the nominal operation of the Carnot battery. This reduction in low pressure resulting from the discharge of the storage module 3 is advantageous because the better the pressure ratio between the upstream and downstream sides of the turbine 201, the better its performance.Thus, the lowering of the low pressure due to the discharge. The storage module 3 enables a significant increase in the electrical output of the 200 motor cycle, which is therefore desirable in the context of the operation of a Carnot battery according to the invention. This embodiment is advantageously implemented for subcritical cycles.

[0132] According to the embodiment illustrated in [Fig. 6], which does not include the intermediate circuit 1, the fluid stored in the storage module 3 is released to the additional heat exchanger, which allows the transfer of thermal energy from the stored fluid to the working fluid. Thus, the additional heat exchanger 20, via sensible heat transfer only, lowers the temperature of the working fluid in the working cycle 200. This embodiment is advantageously implemented for transcritical and supercritical cycles.

[0133] The charging phase of the Carnot battery is intended for the conversion of electricity from a cold source 5 via the ejector 101.

[0134] During the charging phase, the Carnot battery according to the invention is illustrated in [Fig.4] detailed below.

[0135] The hot source 6, the motor cycle 200, the injector-cooled cycle, and the cold source supply to the condenser 204 are active during the charging phase. Active means that fluid circulation is occurring. The release of thermal energy stored by the storage module, particularly via the intermediate circuit 1 or the additional heat exchanger 20, which ensures heat exchange between the storage module 3 and the motor cycle 200, is not active; that is, there is no fluid circulation.

[0136] This charging phase is implemented when there is a surplus of electrical energy compared to the demand on the grid. The Carnot battery according to the invention thus makes it possible to store the surplus electrical energy in the form of cold thermal energy. During the charging phase, the operation of the Carnot battery according to the invention is identical to its operation during the stationary phase, with the addition of the operation of the refrigeration machine 100, which allows the storage of electrical energy in the form of cold thermal energy.

[0137] During battery charging, at least a portion of the working fluid flow from the engine cycle is diverted from the turbine 201 and then expanded by the ejector 101 to generate cooling. This cooling is then stored by the storage module 3. After cooling the storage module 3 by evaporating, the flow is therefore in a gaseous state and at low pressure. In order for this flow to be reintegrated into the engine cycle, it is compressed in the ejector 101, driven by a high-pressure flow from the engine cycle.

[0138] The hot source 6 supplies the evaporator 202 of the motor cycle 200.

[0139] The hot source 6 enters the evaporator 202 at a temperature higher than its temperature at the outlet of the evaporator 202. The hot source 6 transfers its thermal energy to the engine cycle 200 through the evaporator 202. The heated engine fluid from the evaporator 202 is sent, at least in part, to the turbine 201 to be expanded and allow the production of electrical energy by its turbine 201 associated with the generator 206. The other part is sent to the ejector 101. The expanded engine fluid at the outlet of the turbine 201 and the mixed fluid from the ejector 101 are combined downstream of the ejector 101, upstream of the condenser 204 and possibly upstream of the first recuperator 203 if it is present. According to the embodiment of [Fig.5], all the working fluid from the evaporator 202 is sent first to the turbine 201 and then to the ejector 101.The mixed fluid from ejector 101 is sent to condenser 204 and possibly via the first recuperator 203.

[0140] The condenser 204 is supplied by the cold source 5 from the environment and which is not supplied or cooled by the storage module 3.

[0141] The mixed fluid from the condenser 204 is partially drawn in by the pump 205. The remaining portion not drawn in by the pump 205 is sent to the refrigeration branch of the refrigeration cycle via an ejector. The fluid sent to the refrigeration branch advantageously flows through the second recuperator 103 and then through the expansion valve 104, where its pressure is reduced before being sent to the evaporator 102. In the evaporator 102, the expanded working fluid cools the fluid contained in the storage module 3. The expanded working flow from the evaporator 102 advantageously flows through the second recuperator 103 before being sent to the second inlet of the ejector 101. Examples

[0142] A Carnot battery according to the invention was simulated using EES (Engineering Equations Solver) software.

[0143] Regarding the hot source 6, its nature, flow rate, and temperature can be arbitrary; however, typical temperature and power assumptions have been adopted. Thus, the hot source 6 of the power plant has been modeled as a heat source 6 at a constant temperature of 130°C, delivering a maximum power of 80 kW, also constant over time. The profile of this hot source 6 is left as a degree of freedom. The cold source 5 is considered to have a constant temperature of 13°C, but infinite power and flow rate. The profile of this source 5 is also a degree of freedom. The assumption of infinite power and flow rate models a Carnot battery whose cold source 5 would be provided by a current water or a reservoir with a limited and constant temperature over time, but with an available flow rate of an order of magnitude greater than the needs of the power plant.

[0144] The component efficiencies were assumed to be constant and are taken from the literature. The adopted efficiency values ​​are given below: Isentropic Turbine 201: 0.75; Generator 206: 0.95; Pumps 4, 205, 11: 0.5; Isentropic Ejector 101: 0.2

[0145] Losses during storage were neglected and a constant pinch was adopted for the various exchangers of the BCG.

[0146] Data on the performance of the Carnot battery according to the invention are given below:

[0147] Grafting degree: 10.3%

[0148] Charge / discharge ratio: 300%

[0149] Motor cycle efficiency during the stationary phase: 8.0%

[0150] Motor cycle efficiency during the charging phase: 8.7%

[0151] Motor cycle efficiency during the discharge phase: 7.7%

[0152] BCG Return Report: 64.3%

[0153] The degree of integration is an indicator used to obtain information about the battery size. The battery size is considered here in relation to the services it can provide to the grid in terms of power modulation of the thermal power plant's output. Here, the simulated Carnot battery has a degree of integration of approximately 10%, meaning that it will be able to modulate the engine cycle power, during discharge, by 10% of the nominal output. The simulated Carnot battery here is therefore of sufficient size to provide services to the grid.

[0154] The charge-to-discharge ratio is set to 300%, meaning that the charge phase is 3 times longer than the discharge phase.

[0155] The Carnot battery restitution ratio here is 64.3%, which means that 64.3% of the electricity that was consumed during charging (i.e. stored in the Carnot battery) was returned during the discharge of the Carnot battery.

[0156] The invention is not limited to the embodiments previously described and extends to all embodiments covered by the invention.

[0157] List of references 1. Intermediate circuit 2. Discharge exchanger 3. Storage Module 4. Discharge pump 5. Cold source 6. Hot spring 11. Hot spring pump 20. Additional heat exchanger 101. Ejector 102. Evaporator 103. Second recuperator 104. Regulator 200. Engine cycle 201. Turbine 202. Evaporator 203. First Recycler 204. Condenser 205. Pump 206. Generator A. Fluidic connection between the outlet of the cold storage module and the inlet of the discharge exchanger B. Fluidic connection between the outlet of the discharge exchanger and the inlet of the cold storage module C. line of supply from a first cold source of the engine cycle feeding the discharge exchanger D. Fluid connection between the discharge exchanger and the condenser of the engine cycle E. Return line from the first cold source of the engine cycle out of the condenser F. Fluid connection between the hot source and the evaporator of the engine cycle G. Fluid connection between the evaporator of the engine cycle and the hot source H. Fluid connection between the evaporator of the engine cycle and the turbine or the bypass between the turbine and the ejector. I. Fluidic connection between the engine cycle turbine and the ejector outlet J. Fluid connection between the first recuperator and the engine cycle condenser. K. Fluid connection between the engine cycle condenser and the first recuperator. K', Fluid connection between the engine cycle condenser and the additional heat exchanger. K”, fluidic connection between the additional heat exchanger and the first recuperator L. Fluid connection between the first recuperator and the evaporator of the engine cycle. M. Bypass fluid connection of the first recuperator. N. Bypass fluid connection of the first recuperator O. Fluidic connection between the fluidic connection H and the turbine P. Fluidic connection between the fluidic connection H and the first inlet of the ejector Q. Fluidic connection between the ejector outlet and the junction with connection I R. Fluidic connection between fluidic connections I and Q and the first recuperator S. Bypass fluid connection of the fluid branch between the downstream end of the engine cycle condenser and the evaporator of the refrigeration branch T. Fluid connection between the evaporator of the refrigeration branch and the 2nd inlet of the ejector

Claims

1. Demands Carnot battery including a power cycle (200) for converting thermal energy into electricity, comprising a working fluid circulation circuit, an evaporator (202) providing heat exchange with a hot source (6), a turbine (201), a condenser (204) providing heat exchange with a cold source (5), and a pump (205), the circulating power circuit being configured to provide successive fluid connection of the evaporator (202), the turbine (201), the condenser (204), the pump (205), and then the evaporator (202), characterized in that it comprises an ejector refrigeration cycle (SERS) comprising a working fluid circulation refrigeration circuit comprising three branches arranged in parallel: • a drive branch on which are arranged the pump (205) and the evaporator (202) of the motor cycle (200) intended to ensure heat exchange between a heat source (6) and the working fluid, and • a refrigeration branch arranged in a bypass of the engine cycle extending from downstream of the condenser (204) of the engine cycle (200) upstream of the pump (205) of the engine cycle (200) and on which are arranged an expansion valve (104) and an evaporator (102) intended to ensure heat extraction from a source to be cooled, and • a mixing branch on which are arranged an ejector (101) intended to ensure the mixing of the working fluid from the driving branch and the working fluid from the refrigeration branch and the condenser (204) of the engine cycle (200) intended to ensure a heat exchange between a cold source (5) and the mixed working fluid, from the ejector (201), the ejector (201) comprising a first inlet fluidically connected to the drive branch downstream of the evaporator (202) of the drive cycle (200), a second inlet fluidly connected to the refrigeration loop downstream of the evaporator (102) of the branch refrigeration and an outlet fluidically connected to the condenser (204) of the engine cycle (200) and a thermal energy storage module (3) comprising a fluid intended to store cold thermal energy and forming the source to be cooled of the evaporator (102) of the refrigeration branch, the thermal energy storage module (3) being thermally connected to the condenser (204) of the engine cycle (200) ensuring the thermal transfer of cold thermal energy from the fluid stored in the energy storage module (3) to the engine cycle (200).

2. Carnot battery according to the preceding claim in which the turbine (201) is arranged on the drive branch downstream of the evaporator (202) of the engine cycle (200) and upstream of the ejector (101).

3. Carnot battery according to claim 1 wherein the turbine (201) is arranged on a bypass conduit arranged between the downstream of the evaporator (202) of the engine cycle (200) and the downstream of the ejector (101) upstream of the condenser (204) on the mixing branch.

4. Carnot battery according to any one of the preceding claims comprising an intermediate circuit (1) ensuring the heat transfer of cold thermal energy from the fluid stored in the cold thermal energy storage module (3) and the condenser (204) of the engine cycle (200), the intermediate circuit (1) comprising a discharge heat exchanger (2) ensuring the heat transfer of cold thermal energy from the fluid to the cold source (5) supplying the condenser (204) of the engine cycle (200).

5. Carnot battery according to any one of the preceding claims comprising a first recuperator (203) arranged at the interface of the drive branch and the mixing branch between the downstream of the ejector (101) and the downstream of the pump (205).

6. Carnot battery according to any one of the preceding claims comprising a second recuperator (103) arranged on the refrigeration branch between the downstream of the condenser (204) of the engine cycle (200) and the downstream of the evaporator (104) of the refrigeration branch.

7. A method for producing electrical energy by a Carnot battery according to any one of the preceding claims, comprising a charging step comprising a heat exchange in the evaporator (202) of the power cycle (200) between the hot source (6) and the working fluid to ensure the evaporation of the working fluid, a circulation of at least a portion of a working fluid stream in the turbine (201) of the power cycle (200) ensuring the expansion of the working fluid from the evaporator (202) of the power cycle (200) and the production of electricity by an associated generator (206), a circulation of at least a portion of a working fluid stream in the ejector (101) from the turbine (201) or the evaporator (202) of the power cycle (200), a mixing in the ejector (101) of the working fluid from the power branch and the working fluid from the cooling branch, a diversion of at least a portion of the working fluid stream between the downstream of the condenser (204) of the engine cycle (200) and the upstream of the pump (205) towards the refrigeration branch,the storage of cold thermal energy in the storage module by heat exchange (3) in the evaporator (104) of the refrigeration branch between the working fluid and the storage fluid.

8. Method of producing electrical energy according to the preceding claim comprising a cold thermal energy discharge stage including, a destocking of the fluid from the storage module, a heat exchange in the discharge heat exchanger (2) between the destocked fluid from the thermal energy storage module (3) and a cold source (5) to lower the temperature of the cold source (5), a heat exchange in the condenser (204) of the engine cycle (200) between the cooled cold source and an engine fluid circulating in the engine cycle (200) allowing condensation of the engine fluid.

9. A method for producing electrical energy according to the preceding claim, wherein the cold thermal energy discharge step comprises a heat exchange in the evaporator (202) of the engine cycle (200) between the heat source (6) and the engine fluid to ensure the evaporation of the engine fluid, an expansion of the engine fluid from the evaporator (204) in the turbine (201) of the engine cycle allowing the production of electricity by an associated generator (206).

10. A method for producing electrical energy according to any one of the three preceding claims, comprising a stationary operating step including heat exchange in the evaporator (202) of the engine cycle (200) between the heat source (6) and the engine fluid to ensure evaporation of the engine fluid, expansion of the engine fluid from the evaporator (202) of the engine cycle (200) in the turbine (201) of the engine cycle (200) enabling the production of electricity by an associated generator (206), and heat exchange in the condenser (204) of the engine cycle (200) between the cold source (5) and the engine fluid to ensure condensation of the engine fluid.