SYSTEM HAVING A LIQUID AIR ENERGY STORAGE APPARATUS AND POWER PLANT.

Abstract

The invention relates to a system having a liquid air energy storage apparatus and power plant, having a loading component comprising a compressor for compressing the supplied air and comprising a liquefier located next to said compressor and serving to liquefy the air, having a storage component comprising an air storage tank for storing the liquefied air, and having a discharge component comprising an evaporation apparatus for converting the liquid air into gaseous compressed air, wherein thermal energy is supplied to the evaporation apparatus via a first heat line, and comprising an expansion apparatus serving to expand the compressed air and having a turbine and a generator connected to the turbine.According to the invention, an apparatus for the permanent electrolysis of water is provided, comprising at least one first heat exchanger. The thermal energy generated during electrolysis is absorbed by a fluid flowing through the first heat exchanger. The first heat exchanger is connected to the first heat line, such that the thermal energy generated during electrolysis is dissipated through the first heat exchanger by means of the fluid and fed to the evaporation apparatus.

Description

SYSTEM HAVING AN AIR ENERGY STORAGE DEVICE LIQUID AND POWER PLANT The invention relates to a system having a liquid air energy storage apparatus and a power plant of the type specified in the preamble of claim 1, and a method for operating said system. In many countries, the proportion of electricity generated from solar and wind power is steadily increasing. For this reason, electrical energy storage is becoming increasingly important. This is because, while hydroelectric power plants and dams can largely generate electricity in line with demand, and large-scale power plants such as gas, coal, or nuclear plants can at least provide a constant output, wind and solar power plants generate electricity completely independently of demand, only when there is wind or sun. Solar energy is often generated inversely to energy demand. Currently, for example, enormous amounts of wind power are being generated in Lower Saxony but are wasted because the grid cannot absorb them.In Europe, in 2019, the. -2 Wind energy temporarily reached the production of 100 nuclear power plants. Electricity storage in liquid air energy storage systems, also known as liquid air energy storage (LAES) technology, plays a crucial role in such energy systems. The major advantage of liquid air energy storage systems compared to pumped storage systems is their precise installation on-site, almost regardless of local conditions. Therefore, no special geological conditions or excavation work are required. Furthermore, the construction period for a 2 x 150 MW pumped storage power plant is 10 years. In contrast, systems incorporating liquid air energy storage and a power plant are ready for operation after a maximum design and construction period of 18 months. In the well-known liquid air energy storage apparatus and power plant, ambient air is liquefied with the help of electricity using the Linde process, stored in cryogenic (super-cold) storage tanks, and, if necessary, converted back into electricity in an expansion turbine and fed into an electrical grid. A liquid air energy storage system and power plant essentially consists of three main components: a charging component, a storage component, and a discharge component. The charging component is operational when energy is to be stored from electricity that is not needed, i.e., at midday, for example, when the sun is shining. Using the supplied electricity, ambient air is compressed in the charging component with the aid of a compressor and liquefied by expansion at -190 °C in a manner known per se using the Linde process, or with the aid of an expansion turbine and a brake generator. Subsequently, the liquid air is stored at near ambient pressure in an insulated storage tank—the storage component—at a density more than 700 times that of ambient air.When more energy is needed, the liquid air is pressurized by a pump, heated in an evaporator, vaporized, and finally expanded to ambient pressure in the discharge component through a turbine connected to a generator, or multiple turbines connected to generators. The electricity is then fed back into the electrical grid via the generator. The efficiency of the liquid air energy storage system and power plant apparatus can be increased by coupling an external thermal energy source to it. -4 evaporation device as liquid air is converted into compressed air. It is known from DE 10 2015 109 898 By integrating liquid air energy storage and power plant equipment into a system with a steam power plant to utilize waste heat, i.e., thermal energy, to increase the efficiency of the discharge component and, therefore, of the liquid air energy storage and the power plant equipment as a whole. However, steam power plants are relatively expensive and subject to strict environmental regulations. This is why they can only be built in selected locations. In most cases, steam power plant sites are not near wind turbines or solar power plants. Furthermore, the steam power plant disclosed in DE 10 2015 109 898 Al includes a boiler fueled by fossil gas, where material safety issues can arise as a result of alternating very high and low temperatures. It should also be noted that high-alloy steels are not designed to withstand temperatures of around -190 °C for air liquefaction. Moreover, the efficiency of such a system is insufficient, as is its carbon footprint. -5For this reason, the object of the invention is to improve the known system of the preamble of claim 1 in such a way that, avoiding the aforementioned disadvantages, on the one hand, energy can be stored and extracted again in a relatively economical manner and, furthermore, the external energy from an energy-intensive process can be used for the production of other green products. This object is achieved through the characterizing features of claim 1 together with the features of its preamble. Dependent claims relate to advantageous additional embodiments of the invention. The invention is based on the idea that a continuous electrolysis process for the production of hydrogen and oxygen continuously generates waste heat within a temperature range of approximately 40°C to 90°C, thus generating thermal energy corresponding to the optimal amount of heat required for the process of vaporizing liquid air into compressed air. Consequently, integrating this electrolysis process into a system that includes liquid air energy storage and a power plant will enhance its overall efficiency. -6 increase significantly. It should also be noted that, in the medium term, hydrogen and oxygen will become core components of a secure, sustainable, and economical energy supply based on renewable energy. Integrating hydrogen into energy systems will reduce the costs of the energy transition while increasing security of supply. Furthermore, the demand for hydrogen is substantial and growing for a wide variety of applications, including the increasing sales of hydrogen-powered vehicles, which require approximately 5 kg of hydrogen per 500 km. Currently, 600 billion Nm3 of hydrogen are consumed annually in refineries and petrochemical plants, 40 billion Nm3 of which are consumed in Germany alone. According to the invention, the system is therefore provided with a device for the permanent electrolysis of water, having at least one first heat exchanger through which the thermal energy generated during electrolysis is absorbed by a fluid flowing through said first heat exchanger. At least one first heat line is provided that supplies thermal energy to the evaporation device via the fluid. The first heat exchanger is connected to the first heat line such that the thermal energy generated during electrolysis is dissipated through -7 from the first heat exchanger through the fluid and is supplied to the evaporation device. This is a simple way to feed the thermal energy generated in the continuous electrolysis, i.e., the production of Ha and O2, to the evaporation device of the liquid air energy storage and the power plant apparatus and regulate it. In one embodiment of the invention, the evaporation device is designed as a water bath evaporator. Such a water bath evaporator is essentially a heat exchanger through which the first heat line passes and transfers thermal energy via a water bath to at least one line carrying the liquefied air. This process is used to convert the liquefied air into gaseous compressed air. A water bath evaporator is characterized by its robust and reliable design and has a wide capacity range. Such water bath evaporation devices are commonly used in cryogenic plants to evaporate liquefied gases such as air, oxygen, nitrogen, argon, and natural gas. This is done at a loading rate of approximately 500 to 195,000 Nm³ / h. Up to three different liquefied gas streams can be processed in a single water bath evaporation device. Preferably, two first heat exchangers are provided, with one first heat exchanger used for oxygen recovery and the other first heat exchanger used for hydrogen recovery in the water electrolysis device in order to absorb the thermal energy generated during electrolysis through the fluid flowing through the first two heat exchangers. Through the first two heat exchangers, almost all the waste heat from the permanent electrolysis device should be transferred to the fluid and, through the latter, finally to the evaporation device. In another embodiment of the invention, the water electrolysis device for splitting water into hydrogen and oxygen using electric current operates on the principle of proton exchange membrane electrolysis (proton exchange membrane or polymer electrolyte membrane, PEM) and is designed for this purpose. The two half-cells are separated by a gas-tight membrane. The main advantage of this technology is its efficient charge-switching behavior. Compared to other methods, fluctuating amounts of electricity can be processed more quickly. Furthermore, operation in the partial-charge range is possible across the entire bandwidth. Alternatively, the permanent electrolysis device for the production of H2 and O2 can operate on the principle of alkaline electrolysis and be designed for this purpose. In alkaline electrolysis (AEL), metal electrodes are immersed in an alkaline aqueous solution. The half-cells in which the electrodes are suspended are separated by a permeable membrane. When a voltage is applied, oxygen is produced at the anode and hydrogen at the cathode. This technology is characterized by high long-term stability and low investment costs. Furthermore, rare precious metals are not required for the electrode material. Despite their simple design, these types of systems currently achieve the highest efficiencies. However, particularly with regard to the use of volatile power supplies, there is the problem of slow charge switching and a relatively low partial charge range. To further increase the efficiency of the system, the compressor of the load component of the 20 air liquid energy storage apparatus and power plant interacts with at least one second heat exchanger, with the compressor fluid flowing through said second heat exchanger absorbing the heat generated during the compression of the air and dissipating it in the direction of the evaporation device. -10For this purpose, the second heat exchanger can be connected to the evaporation device via a second heat line to supply the thermal energy generated during compression to the evaporation device. In another further embodiment of the invention, at least a third heat exchanger is connected downstream of the evaporation device, which is used to supply additional thermal energy to the compressed air from the evaporation device and to set the required temperature of the compressed air. The evaporation device can be connected to the third heat exchanger via the first heat line and / or the second heat line and use the remaining thermal energy of the fluid leaving the evaporation device to adjust the temperature of the compressed air through the third heat exchanger. Preferably, the third heat exchanger is designed as an air-to-water heat exchanger. More specifically, the third heat exchanger is connected to the first heat exchanger via the first heat line, forming a first fluid circuit. -11 Alternatively or additionally, the third heat exchanger can be connected to the second heat exchanger via the second heat line, thus forming a second fluid circuit. This also makes use of the thermal energy available in the liquid air energy storage and power plant equipment to increase the overall system efficiency. The third heat exchanger is preferably used to heat the compressed air to ambient temperature, but also to regulate the inlet temperature for the first heat exchanger of the device for the continuous production of H2 and O2 during electrolysis for optimal operation. Preferably, the first and / or second heat lines can also have branches at the heat exchangers to allow for proper regulation of the compressed air temperature. For example, the first heat line has a branch to the evaporator to also directly supply a greater proportion of thermal energy to the third heat exchanger. The objective of the heat exchanger design is to achieve an effective heat balance in the system. The first line of The heat exchanger, the second heat line, and the fluid are used to enable simple transport of thermal energy between the individual components of the system. It is also possible to have multiple evaporation devices, multiple first, second, and third heat exchangers, and heat lines connecting them, and therefore multiple fluid circuits. However, the desired sizing and optimization of the system is the object of the invention. To ensure that the heat supply process, and therefore the evaporation of liquid air into compressed air, takes place continuously, an intermediate compressed air tank is installed in the discharge component of the liquid air energy storage and power plant apparatus. The above objective is also achieved by a method for operating a system comprising a liquid air energy storage apparatus, a power plant, and a device for a continuously operating electrolysis plant. The method is preferably applicable to the system just described. According to the method, the thermal energy from the waste heat of the continuous electrolysis device is used to supply it to an evaporation device for a discharge component of the liquid air energy storage apparatus and the -13 Power plant apparatus for the conversion of liquefied air into gaseous compressed air and electrical energy. Preferably, the thermal energy from the waste heat of an electrolyzer of the device for permanent electrolysis is used for this purpose. According to a further advantageous development of the invention, the thermal energy of a compressor can be used 10 additionally to compress the supplied air from a loading component of the liquid air energy storage and power plant apparatus in order to supply it to the evaporation apparatus of the unloading component of the liquid air energy storage and power plant apparatus for 15 the conversion of liquefied air into gaseous compressed air. According to another embodiment of the invention, thermal energy is supplied to the evaporation device of the discharge component of the liquid air energy storage apparatus 20 and the power plant via a fluid, particularly in connection with a first heat exchanger that is connected to a heat line supplying and discharging the fluid. The fluid can be fed to the evaporation device at a temperature between 40°C and 90°C. -14Preferably, thermal energy is permanently supplied to the evaporation device of the discharge component, and in the evaporation device the liquefied air is continuously converted into gaseous air and supplied to an intermediate compressed air storage. To compensate, in particular, for peak loads on the electrical grid, compressed gaseous air from the intermediate compressed air tank is fed to an expansion device with a turbine and a generator as needed. The electricity produced by the generator is fed into an existing electrical grid for regulation, in order to balance consumption and generation. Preferably, the fluid in the first heat line can be cooled before entering the first heat exchanger to optimize the device's efficiency for permanent water electrolysis. Preferably, the fluid in the second heat line can also be cooled before entering the second heat exchanger. Using energy from renewable sources for energy storage is considered particularly advantageous. -15 of liquid air and the power plant apparatus and / or the device for permanent water electrolysis. The invention is characterized by the fact that, due to optimized thermal energy transfer between the device for continuous water electrolysis and the discharge component of the liquid air energy storage system and the power plant apparatus, the system efficiency is increased. Thermal energy can be absorbed during the continuous production of H2 and O2 for 24 hours. Air liquefaction occurs when there is wind and sunlight. The evaporation of the liquid air for energy recovery is intended for nighttime and / or peak load periods. The additional advantages, features, and possible applications of the present invention will become evident from the following description, in which reference is made to the embodiments illustrated in the drawings. Throughout the description, claims, and drawing, those terms and associated reference signs are used as listed in the Reference Sign List below. In the drawings, -16Fig. 1 is a schematic view of a system according to an embodiment of the invention; Fig. 2 is another detailed schematic view comprising two water bath evaporation devices connected in series and an air / water cooler of a discharge component connected thereto in cooperation with two fluid circuits of the system according to the invention, and Fig. 3 is another schematic view of the modular structure of the system according to the invention. Illustrated in Fig. 1 is a system 10 according to an embodiment of the invention. The system 10 comprises a liquid air energy storage apparatus and power plant 12 and an apparatus 14 for permanent water electrolysis. The liquid air energy storage apparatus and power plant 12 essentially includes three main components, namely a charging component 16, a storage component in the form of liquid air storage 18, and a discharge component 20. -17 Electrical power is supplied to an electric motor 24 of the load component 16 from an electrical network 22, to which the motor 24 is connected and drives a compressor 26 as required. An air intake filter 28 is connected upstream of the compressor 26, through which ambient air is supplied, among other things, to the compressor 26 during the operation of the load component 16. Compressed air from compressor 26 is fed to a dryer 34 via an air line 30 through a second heat exchanger 32 of the load component 16. Thermal energy is extracted from the compressed air, which is heated by compression, using this second heat exchanger 32. For this purpose, the second heat exchanger 32 of the load component 16 is connected to a second heat line 36 of a second fluid circuit 38 to dissipate the thermal energy. This will be discussed later. In the dryer 34, compressed air is cleaned of water vapor, hydrocarbons and carbon dioxide in a manner known per se. Compressed air is fed to an air liquefier 40, which includes a heat exchanger 42, a regulating valve 44, an expansion turbine 46 with a brake generator 48 connected -18 to generate electricity, an expansion valve 50 and an expansion tank 52. In the air liquefier 40, the dry, compressed air is first fed to the heat exchanger 42. In the heat exchanger 42, a first partial flow of the compressed air branches off and is directed to the expansion turbine 46 through the regulating valve 44, where the compressed air expands to ambient pressure and thus drives the expansion turbine 46. The expansion turbine 46 in turn drives the brake generator 48 which generates electricity and transmits it through an electrical control center 54 with inverter, transformer, etc. to the electrical network 22 or to the system loads 10, for example the compressor 26. The now heavily cooled air from the expansion turbine 46 is then fed to the heat exchanger 42, where it extracts a considerable amount of thermal energy from the second partial flow, cooling it significantly. The first partial flow, thus heated, is returned to the air intake filter 28 via the dryer 34 and from there to the compressor 26. In heat exchanger 42, the second partial flow is cooled just before the liquefaction point and then passes through an expansion valve 50, where the air drops below the liquefaction point and enters the expansion tank 52. Through the expansion tank 52 and another regulating valve 56, liquid air is introduced into the air storage tank 18 at ambient pressure and approximately -190 °C. In the air storage tank 18, the liquid air is stored until energy is required to balance the maximum loads. For energy extraction, liquid air is drawn from air storage 18 by a pump 58 driven by a motor 60. Through air line 30, the liquid air is first fed to an evaporation device in the form of a water bath evaporator 62, then fed as compressed air to a third heat exchanger 64, and finally as compressed air to an intermediate compressed air tank 66. In the water bath evaporator 62, thermal energy is supplied via a first heat line 68 and a second heat line 38, converting the liquid air into compressed air at a pressure of approximately 40 bar. In the third heat exchanger 64, the compressed air is heated to ambient temperature or higher and then stored in the intermediate compressed air tank 66.The process of extracting liquid air from air storage 18 and supplying compressed air can be continuous. -20To facilitate the adjustment of the temperature of the compressed air supplied to the intermediate compressed air tank 66, a bypass line 70 is provided, into which a bypass valve 72 is inserted. The bypass line 70 is connected to the section of the air line 30 that connects the water bath evaporator 62 to the third heat exchanger 64. Furthermore, the bypass line 70 is connected to the section of the air line 30 that connects the third heat exchanger 64 to the intermediate compressed air tank 66. In this way, the cooler compressed air from the water bath evaporator 62 can be mixed with the warmer compressed air from the third heat exchanger 64, allowing the temperature of the compressed air entering the intermediate compressed air tank 66 to be adjusted to a predetermined temperature. In the intermediate compressed air tank 66, the compressed air supplied through the air line 30 is continuously stored until power is required, for example, to balance peak loads on the electrical network 22. For this purpose, the intermediate compressed air tank 66 is connected to a main turbine 76 with a power generator 78 connected through a pneumatic valve 74 and another part of the air line 30. In the main turbine 76, the compressed air is expanded from about 40 bar to ambient pressure, -21 thus driving the main turbine 76 with the power generator 78 connected to it to generate electricity. The electricity generated is supplied to the electrical grid 22 for regulation. The apparatus 14 for continuous water electrolysis consists of several PEM 80 electrolyzers, which are connected to the electrical network 22 from which they receive the electrical power for the continuous electrolysis of water for the production of H2 and O2. For at least 7,000–8,000 hours per year, the PEM 80 electrolyzers continuously produce hydrogen and oxygen 24 hours a day. The oxygen is supplied to an oxygen storage tank 88 and the hydrogen to a hydrogen storage tank 86 and is processed or transferred as required in a known manner. The thermal energy generated during oxygen production, as well as during hydrogen production, is dissipated through fluid circuits 90 and 92, and through a heat exchanger 94 associated with the oxygen production fluid circuit 92, and through a heat exchanger 96 associated with the hydrogen recovery fluid circuit 92. The first heat line 68 connects the first two heat exchangers 94 and 96 to each other and absorbs thermal energy from fluid circuits 90 and 92 through the fluid flowing in heat line 68. -22The heat line 68 forms a first fluid circuit 98. More specifically, the heat line 68 runs from the first two heat exchangers 94, 96 to the water bath evaporation device 62 to release there the thermal energy stored in the fluid of the heat line 68 to a water bath, through which the liquefied air from the air line 30 is heated again and causes it to evaporate. The heat line 68 continues from the water bath evaporation device 62 to the third heat exchanger 64 and back to the first two heat exchangers 94 and 96. The first fluid circuit 98 formed by the first heat line 68 is therefore a closed circuit. In addition, a bypass line 100 with a bypass valve 102 is provided from the first fluid circuit 98, which short-circuits the first heat line 68 while bypassing the third heat exchanger 64. This is a simple way of adjusting the thermal energy to be supplied to the compressed air in the air line 30 by the fluid in the first heat line 68 through the third heat exchanger 64. In addition, an equalization line 104 is provided with a compensation valve 106 connecting the first part -23 Heat line 68 downstream of the third heat exchanger 64 to the portion of the second heat line upstream of the second heat exchanger 32. This is to transfer fluid from the first heat line 68 of the first fluid circuit 98 to the second heat line 36 of the second fluid circuit 38, thereby introducing thermal energy from the first fluid circuit 98 into the second fluid circuit 38. This serves to regulate the return temperature of the second heat line 36 during the operation of the load component 16. Fig. 2 is a schematic view of substantially the first fluid circuit 98 and the second fluid circuit 38. The individual components have the parts of system 10 as described with reference to Fig. 1. However, for reasons of clarity, aspects of the view in Fig. 2 have been omitted. The first heat line 68 runs from the first heat exchangers 94, 96 of the apparatus 14 for permanent hydrogen electrolysis to two water bath evaporation devices 62a, 62b connected in series, then to the third heat exchanger 64 in the form of an air / water cooler, and finally back to the first heat exchangers 94, 96. For reasons of clarity, the bypass line 100 with bypass valve 102 is not shown here, nor is the equalization line 104 with compensating valve 106. -24The second heat line 36 extends from the second heat exchanger 32 in the compressor 26 to the first water bath evaporator device 62a, then to the second water bath evaporator device 62b, then to the third heat exchanger 64 and back to the second heat exchanger 32. Additionally, air storage 18 is shown with air line 30. Air line 30 runs from air storage 18 through the two water bath evaporation devices 62a, 62b through the third heat exchanger 64 to the intermediate compressed air tank 66. A fan is provided in the third heat exchanger 64 to cool the fluid from the first heat line 68 before it enters the first heat exchanger 94, 96, and to cool the fluid from the second heat line 36 before it enters the second heat exchanger 32. This clearly shows that the waste heat from apparatus 14 for the permanent electrolysis of hydrogen and the waste heat from compressor 26 are used as thermal energy that is continuously supplied to the discharge component 20 through the water bath evaporation devices 62a, 62b and the third -25 heat exchanger 64 in a 24-hour / 7-day-a-week operating mode. Fig. 3 is a schematic view of the basic structure of system 10 described with reference to Figs. 1 and 2. As shown, this system 10 has two liquid air energy storage devices and power plants 12 arranged in parallel. Furthermore, Figure 3 illustrates four electrolyzers 80, each with 24 units 14 for continuous water electrolysis, which are of modular design and can be expanded as needed. These electrolyzers 80 for the continuous production of hydrogen and oxygen interact with heat exchangers 94 and 96. The liquid air energy storage unit and power plant 12 includes the charging component 16, the air storage unit 18, and the discharge component 20 with the water bath evaporation device 62, the third heat exchanger 64, the compressed air intermediate tank 66, and the main turbine 76 with the power generator 78. All these components are shown schematically only to illustrate the modular design. Furthermore, the liquid air energy storage unit and power plant 12 and the -26 Apparatus 14 for permanent hydrogen electrolysis also includes all the features described with reference to Fig. i. An electrolyzer 80, which has an energy demand of 17.5 MW, currently produces 8,160 kg of hydrogen per day. In doing so, it transfers 4 MWh of heat through heat exchangers 94, 96 to the water bath evaporation device 62 via the first fluid circuit 98 through the fluid flowing in the first heat line 68. The water bath evaporator 62 includes, for example, a 400 m³ water bath, which requires 18.6 MWh to heat from 10 °C to 50 °C. 40 m³ / h of liquid air is introduced into the water bath evaporator 62 via pump 58 and the associated air-heated water bath evaporator 62, while 28,000 Nm³ / h of compressed air is supplied from the water bath evaporator 62 to the third heat exchanger 64. Here, the temperature difference between the introduced liquid air and the discharged compressed air is 100 °C and therefore corresponds to an energy input through the water bath evaporator of approximately 9.5 MWh. The volume of the liquid air storage unit 18, -27E1, is 1,200 m³, for example, which corresponds to approximately 165 MWh of stored energy. Approximately 20 MW of energy are supplied to the compressor 26 by the motor 24 to compress the intake air 5. The thermal energy is released through the second heat exchanger 32, whose thermal energy is delivered to the water bath evaporator 62 through the second fluid circuit 38 via the fluid flowing in the second heat line 36. During the operation of the liquid air energy storage and power plant apparatus 12, the turbine 76 with connected generator 48 can be used to generate power which is then supplied to the electrical grid 22. Due to the diverse portfolio of compressors, reducers, and generators, detailed specifications should only be defined or adapted during the planning phase. -28List of Reference Signs 10 System 12 liquid air energy storage devices and 5 power plants 14 permanent water electrolysis devices 16 load components 18 liquid air storage 20 discharge components 10 22 electrical network 24 electric motor 26 compressors 28 air intake filter 30 overhead line 15 32 Second heat exchanger arranged in the load component 16 34 dryer 36 heat line, second heat line 38 fluid circuit, second fluid circuit 20 40 air liquefier 42 heat exchangers 44 regulating valve 4 6 expansion turbine 48 brake generator 25 50 expansion valve 52 Expansion tanks 54 Electrical control center 56 Additional regulating valve upstream of air storage 18 58 Pump 60 Pump motor 58 62 Water bath evaporators 6 4 Third heat exchanger 66 Pressurized air intermediate tank 68 First heat line 70 Bypass line 70 72 Bypass valve 74 Pneumatic valve 76 Main turbine 78 Power generator 80 Electrolyzer 86 Oxygen storage tank 88 Hydrogen storage tank 90 Fluid circuit - oxygen 92 Fluid circuit - hydrogen 94 Heat exchanger - oxygen 96 Heat exchanger - hydrogen 98 First fluid circuit 100 Bypass line 102 Bypass valve 104 equalization lines, 106 equalization valves

Claims

1. A system comprising: a. an energy storage apparatus and liquid air power plant, having i. a loading component comprising a compressor for compressing the supplied air and comprising a liquefier, located adjacent to said compressor and serving to liquefy the air, ii) a storage component comprising an air storage tank for storing the liquefied air, and iii) a discharge component comprising an evaporation apparatus for converting the liquid air into gaseous compressed air, wherein thermal energy is supplied to the evaporation apparatus via a first heat line, and comprising an expansion apparatus serving to expand the compressed air and having a turbine and a generator connected to the turbine; characterized by b.A permanent water electrolysis apparatus having at least a first heat exchanger, whereby the heat energy generated during electrolysis is absorbed by a fluid flowing through the first heat exchanger, said first heat exchanger being connected to the first heat line in such a way that the thermal energy generated during electrolysis is dissipated through the first heat exchanger by means of the fluid and fed to the evaporation apparatus.

2. The system according to claim 1, characterized in that the evaporation apparatus is a water bath evaporation apparatus.

3. The system according to the previous ones, characterized by heat exchangers, is associated with the first hydrogen heat exchanger in the apparatus for any of claims 1 because two first heat exchangers are provided, one of which is for oxygen recovery and the other is associated with permanent electrolysis water recovery.

4. The system according to any of the preceding claims, characterized in that the apparatus for the permanent electrolysis of water is a proton exchange membrane electrolyzer (proton exchange membrane or polymer electrolyte membrane, or PEM).

5. The system according to any of claims 1 to 3 above, characterized in that the apparatus for permanent water electrolysis is designed as an alkaline electrolyzer.

6. The system according to any of the preceding claims, characterized in that the compressor of the load component cooperates with at least a second heat exchanger, the fluid flowing through the second heat exchanger absorbs and dissipates the heat energy generated during the compression of the air.

7. The system according to claim 6, characterized in that the second heat exchanger is connected to the evaporation apparatus via a second heat line in order to supply the thermal energy generated during compression to the evaporation apparatus.

8. The system according to any of the preceding claims, characterized in that at least one third of the heat exchanger is connected downstream of the evaporation apparatus, the third heat exchanger being used to supply additional thermal energy to the compressed air from the evaporation apparatus and to establish the required temperature of the compressed air.

9. The system according to claim 8, characterized in that the evaporation apparatus is connected to the third heat exchanger through the first heat line and / or the second heat line and uses the remaining heat energy of the fluid leaving the evaporation apparatus to adjust the temperature of the compressed air through the third heat exchanger.

10. The system according to or 9 above, characterized heat is designed as any of claims 8 because the third heat exchanger is an air-water heat exchanger.

11. The system according to any of claims 8 to 10 above, characterized in that the third heat exchanger is connected to the first heat exchanger via the first heat line and forms a first fluid circuit.

12. The system according to claims 6 and 8, and in particular according to any of the preceding additional claims, characterized in that the third heat exchanger is connected to the second heat exchanger via the second heat line and forms a second fluid circuit.

13. The system according to any of the preceding claims, characterized in that the discharge component of the liquid air energy storage apparatus and power plant has an intermediate compressed air tank.

14. The system according to claim 13, and in particular according to any other of claims 8 to 12, characterized in that the third heat exchanger is connected upstream of the intermediate compressed air tank.

15. A method of operating a system comprising a liquid air energy storage apparatus and power plant and an apparatus for permanent water electrolysis, in particular a system according to any of the preceding claims, wherein the thermal energy from the waste heat of the apparatus for permanent water electrolysis is used to supply it to an evaporation apparatus of a discharge component of the liquid air energy storage apparatus and power plant (12) for the conversion of liquefied air into gaseous compressed air.

16. The method according to claim 15, characterized in that the heat energy from the waste heat of an electrolyzer is used by the apparatus for the permanent electrolysis of water.

17. The method according to any of claims 15 or 16 above, characterized in that the thermal energy of a compressor is further used to compress the supplied air from a load component of the liquid air energy storage apparatus and power plant in order to supply it to the evaporation apparatus of the discharge component of the liquid air energy storage apparatus and power plant for the conversion of liquefied air into gaseous compressed air.

18. The method according to any of claims 15 to 17 above, characterized in that the evaporation apparatus of the discharge component of the liquid air energy storage apparatus and power plant is supplied with thermal energy through a fluid.

19. The method according to claim 18, characterized in that the fluid is supplied to the evaporation apparatus at a temperature between 40°C and 90°C.

20. The method according to any of claims 15 to 19 above, characterized in that thermal energy is constantly supplied to the evaporation apparatus of the discharge component through the first heat line, and the liquefied air is converted into gaseous air in the evaporation apparatus as required and supplied to an intermediate compressed air storage.

21. The method according to any of claims 15 to 20 above, characterized in that the gaseous compressed air from the compressed air intermediate storage is supplied as required to an expansion device having a turbine with a generator connected thereto, to drive the turbine and the generator and supply power generated by the generator to the existing electrical grid.

22. The method according to any of claims 21 above, characterized in that the fluid in the first heat line is cooled before entering the first heat exchanger.

23. The method according to any of claims 15 to 22 above, characterized in that the fluid in the second heat line is cooled before entering the second heat exchanger.

24. The method according to any of claims 15 to 23 above, characterized in that energy from renewable sources is used for liquid air energy storage and the power plant apparatus and / or apparatus 5 for permanent water electrolysis.

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