A hydrogen refueling station cooling system

Abstract

The invention relates to a hydrogen refueling station comprising: a hydrogen storage connected to a dispenser via a flow path, a cooling system comprising: a first cooling loop comprising a first heat exchanger thermally connected to at least a part of the flow path; a chiller thermally connected to the first heat exchanger via the first cooling loop; 5 a dry cooler thermally connectable to the chiller via a third cooling loop, the third cooling loop comprising a valve, a thermal energy storage thermally connectable to said chiller via a fourth cooling loop, the fourth cooling loop comprising a valve, a controller configured to control the valve of the third cooling loop to open to establish a coolant flow in the third cooling loop when one or more ambience parameter(s) 10 satisfies a first ambience condition, and thereby thermally connecting the dry cooler to the chiller via the third cooling loop, and the controller is configured to control the valve of the fourth cooling loop open to establish a coolant flow in the fourth cooling loop when the ambience parameter(s) satisfies a second ambience condition, and thereby thermally connecting the thermal energy storage to the chiller via the fourth 15 cooling loop.

Description

A HYDROGEN REFUELING STATION COOLING SYSTEM Field of the invention

[0001] The invention relates to a hydrogen refueling station comprising a hydrogen refueling system, and to a method of cooling a hydrogen flow. Background of the invention

[0002] Cooling is an essential part of various systems, devices and processes, and cooling systems finds its use within a multitude of different industries. For example, in hydrogen refueling, cooling is required to cool pressurized hydrogen during a refueling to avoid overheating. Cooling systems may utilize different types of cooling depending on parameters such as cooling capacity requirements, restrictions related to maximum footprint of the cooling system, and climate conditions. In general cooling in warm climate conditions is challenging and requires cooling systems with the ability to efficiently cool during high ambient temperatures. This ability may be achieved by utilizing wet cooling towers. These wet cooling towers exploit evaporation of a liquid such as water to provide cooling, hence requiring a supply of the liquid.Summary of the invention

[0003] Hydrogen refueling stations located in warm climate conditions may utilize wet cooling towers to provide the required cooling of hydrogen. However, the consumption of water of such wet cooling towers is a clear disadvantage, and more sustainable solutions are required. Furthermore, utilizing a wet cooling tower is only a suitable solution if a sufficient water supply to the tower can be established, which is not always the case.

[0004] The inventors have identified the above-mentioned problems and challenges related to cooling systems for hydrogen refueling stations, and in particular for cooling a flow of hydrogen in hot climate conditions and solved these problems by the present invention as described in this disclosure.

[0005] In an aspect, the invention relates to a hydrogen refueling station comprising: a hydrogen storage fluidly connected to a hydrogen dispenser via a flow path, a cooling system comprising: a first cooling loop configured to conduct a coolant flow, wherein said first cooling loop comprises a first heat exchanger thermally connected to at least a part of said flow path; a chiller thermally connected to said first heat exchanger via said first cooling loop; a dry cooler thermally connectable to said chiller via a third cooling loop configured to conduct a coolant flow, wherein said third cooling loop comprises a valve; a thermal energy storage thermally connectable to said chiller via a fourth cooling loop configured to conduct a coolant flow, wherein said fourth cooling loop comprises a valve; a controller configured to control said valve (V5) of said third cooling loop to an open state to establish a coolant flow in said third cooling loop when said one or more ambience parameter(s) satisfies a first ambience condition, and thereby thermally connecting said dry cooler to said chiller via said third cooling loop; and wherein said controller is further configured to control said valve of said fourth cooling loop to an open state to establish a coolant flow in said fourth cooling loop when said one or more ambience parameter(s) satisfies a second ambience condition, and thereby thermally connecting said thermal energy storage to said chiller via said fourth cooling loop.

[0006] The invention may provide several advantages over the prior art. For example, the hydrogen refueling station according to the invention comprises a cooling system that enable the hydrogen refueling station to refuel vehicles efficiently in hot climate conditions, wherein the temperature (ambience temperature) may rise to 40 degrees Celsius or more. Even in such warm climate conditions, the cooling system can provide efficient cooling, and thereby enable fast refueling of vehicles.

[0007] Furthermore, contrary to other hot climate cooling systems, the cooling system of the invention advantageously does not consume water during operation. While this render the cooling system eco-friendly and sustainable, it also enables the cooling system and thereby the hydrogen refueling station to be implemented in location without a water supply.

[0008] By adapting the operation of the cooling system based on ambience parameter(s) and based on ambience conditions, the cooling system may be capable of adapting to different climate conditions to provide efficient cooling of hydrogen during refueling in vastly different climate conditions. Thereby, the hydrogen refueling station may be implemented at geographical locations with very different climate conditions including hot climates and colder climates.

[0009] A hydrogen refueling station should be understood as intended for refueling fuel cell vehicles including refueling of heavy-duty fuel cell vehicles as well as light- duty vehicles. Also, other types of vehicles could be refueled by a refueling station having a cooling system as described above, including, e.g., aero planes, helicopters, drones, trains, agricultural vehicles, ships, etc.

[0010] Refueling using the refueling station include pressurizing hydrogen, e.g., gaseous hydrogen to pressures sufficient to refueling a receiving vessel of a fuel cell vehicle. Hence, pressurized gas may be understood as having pressure between, e.g., between 20Mpa and 100Mpa such as 35Mpa – 75Mpa, but could in principle be both higher and lower pressures.

[0011] In the context of the invention, a hydrogen storage may be understood to include a container suitable for storing hydrogen. Thus, a hydrogen storage maycomprise different types of hydrogen storages including, e.g., a stationary storage including one or more hydrogen tanks, or a moveable storage such as a trailer comprising one or more hydrogen tanks. In principle, the hydrogen storage may also be a hydrogen storage of an electrolyzer or of an electrolyzer system configured to produce hydrogen. The storage may typically be a local storage, however, the storage could also be a more remote storage.

[0012] In the context of the invention, a flow path should in general be understood as a conductor of a fluid, e.g., a conductor of hydrogen from a storage to dispenser. Thus, a flow path may comprise one or more pipes or conduits, and the conduits may, e.g., be joint by different parts. One part may be a flexible hose from dispenser to a nozzle, another part may be a heat exchanger, further parts may include one or more compressors, valves etc. Flow paths may be utilized to conduct flow of various types of fluid and not necessarily only hydrogen. Other fluids that may be conducted by a flow path include, e.g., different coolants. E.g., cooling loops may comprise flow paths to conduct coolant flow. A flow path may typically at least comprise a pipe suitable for conducting fluid. Flow paths may be made of different materials, including metal material, plastic materials, ceramic materials, etc., to mention a few non-limiting examples. The flow paths should be able to withstand the pressures and temperatures that occur during operation of the hydrogen refueling station.

[0013] In the present context, a cooling loop, e.g., a first cooling loop or a second, third, fourth, or fifth etc. cooling loop, may be understood as a loop of flow paths of a cooling system in which a fluid, typically a coolant, of the cooling system may be circulated. In other words, a cooling loop may be understood as a circuit in which a flow of fluid such as, e.g., a coolant may be circulated. The cooling loop may typically be a closed circuit. E.g., in the first cooling loop, a coolant may be circulated to thermally connect the chiller to the first heat exchanger. A cooling loop may comprise conduits or pipes for conducting a fluid, but may also comprise components such as heat exchangers, valves, etc. When a cooling loop is said to thermally connect two components such as, e.g., two heat exchangers or a chiller and a heat exchanger, it may be understood that the coolant circulating in the cooling loop transfer heat from onecomponent, e.g., from a heat exchanger to the other component, e.g., another heat exchanger or to another cooling loop via a heat exchanger. E.g., heat from a flow of hydrogen in a flow path may be transferred to coolant of the first cooling loop via the first heat exchanger. The first heat exchanger is connected to the first cooling loop and because the coolant may be circulated in the cooling loop, the coolant and thereby the heat transferred to the coolant may be transferred to the chiller. The chiller and the heat exchanger may thereby be understood as being thermally connected via the first cooling loop. The chiller may provide cooling to cool the heated coolant circulating in the first cooling loop. The first heat exchanger and the chiller may thereby sometimes be referred to as being included in the first cooling loop, since coolant circulating in the first cooling loop may typically circulate through the first heat exchanger and the chiller. Notice that cooling loops may thus be understood as a way of conducting thermal energy. Further notice that cooling loops may comprise different component including, e.g., valve(s), fluid pump(s) (sometimes referred to as coolant pumps), compressor(s), various types of sensors etc. E.g., fluid pumps are known in the art to be implemented together with valves in a cooling loop, to circulate fluid in cooling loops when activated. According to an embodiment of the invention, valves of a cooling loop may be controlled between and open state and a closed state in parallel with control of activation and deactivation of one or more circulation pumps of the same cooling loop.

[0014] The term thermally connected may in the context of the invention be understood as two or more components, parts or fluids being connected in such a way that thermal energy may transfer from one component or fluid to the other component or fluid. E.g., heat transferring from one part to another. E.g., when a heat exchanger is thermally connected with e.g., a chiller or a thermal energy storage through a cooling loop, it may be understood that thermal energy from the heat exchanger, e.g., heat may be transferred from the heat exchanger to the chiller or thermal energy storage or vice versa, via the cooling loop comprising a fluid. A heat exchanger may also be thermally connected to a flow path, and in this case, it should be understood that heat may be transferred between the heat exchanger and the flow path, or between the heat exchanger and the fluid flowing in the flow path. A thermal connection may beestablished in different ways, and typically include materials with good heat transfer properties, e.g., including high thermal conductivity.

[0015] In the context of the invention, a chiller may be understood as an arrangement or device that removes heat from a fluid thermally connected to the chiller (e.g. the first cooling loop) and transfer it to a coolant circulated in the chiller. The chiller then dissipates the heat to another coolant or to the surroundings depending on the implementation. A chiller dissipating heat to air, e.g., the surrounding air, may sometimes be referred to as an air-cooled chiller. The chiller may also, e.g., dissipate the heat to another coolant, e.g., the coolant flowing in the third cooling loop or in another cooling loop such as, e.g., the fourth cooling loop. The chiller may then, e.g., be understood as being a liquid-cooled chiller. The liquid cooled chiller may thus dissipate heat from the chiller to coolant a fluid, e.g., a liquid, in a coolant loop thermally connected to the chiller.

[0016] The term dry cooler may in the present context be understood as, e.g., an air cooler. Contrary to other types of coolers, the dry cooler dissipates heat to the surrounding air, and thereby does not consume, e.g., water, contrary to other types of cooling units such as, e.g., water-based cooling towers.

[0017] The term coolant flow may be understood to denote a flow of a fluid such as a coolant. A coolant flow that may typically circulate in a cooling loop, and the coolant may be utilized to transfer thermal energy, e.g. heat. Heat may be transferred to a coolant, and heat may be dissipated from a coolant, e.g., via a heat exchanger.

[0018] The term heat exchanger may be understood as a component, part or device that may be used to transfer thermal energy from one material to another, typically from one fluid to another fluid, typically without mixing the two fluids. A heat exchanger may separate the two fluids by some form of solid barrier made of a material with high thermal conductivity, to facilitate heat transfer across the barrier). Heat exchangers may be designed with a large surface area of the barrier, to facilitate a high heat exchange rate between the two fluids. Various types of heat exchangers may be utilized according to different embodiments of the invention. Non-limiting examplesof suitable heat exchangers may, e.g., include tube-in-tube heat exchangers, plate heat exchangers, fusion bonded plate heat exchanger, finned tube heat exchangers, shell and tube heat exchangers, and double pipe heat exchangers. Notice that heat exchange may be facilitated between fluids of different phases or fluids being in the same phase, e.g., both fluids being in a liquid phase or one fluid being in a gaseous phase and the other being in a liquid phase, or both fluids being in a gaseous phase etc., to name a few non-limiting examples. In principle a heat exchange may also facilitate heat exchange between a solid phase material, e.g., ice, and another fluid in a liquid phase, e.g., between a cooled down material of the thermal energy storage, e.g. ice, and a liquid (coolant) in a cooling loop being thermally connected to the thermal energy storage, e.g., the fourth cooling loop. The heat exchanger may thus be understood to facilitate a thermal connection between two or more fluids or materials between which thermal energy transfer is desired. E.g., a thermal connection between hydrogen flowing in the flow path between the storage and the dispenser of the hydrogen refueling station and a coolant flowing in the first cooling loop, or as another example, a thermal connection between coolant flowing in two cooling loops or between a solid phase material of the thermal energy storage and a liquid phase coolant flowing in, e.g., the fourth cooling loop.

[0019] In the context of the invention a thermal energy storage may refer to a storage of thermal energy. The thermal energy storage allows thermal energy to be stored for later use. Advantageously, the thermal energy storage may store thermal energy for multiple hours or days, and the thermal energy storage may be utilized to provide cooling of hydrogen flowing in the flow path. Different types of thermal energy storages may be utilized according to embodiments of the invention. Non-limiting examples of suitable types of thermal energy storage may, e.g., include different types of thermal batteries from which thermal energy may be stored and released. E.g., thermal energy may be stored by cooling a material of the thermal energy storage, e.g., cooling water or another material contained in a tank, e.g., to establish an ice-bank. Non-limiting examples of suitable thermal energy storages may further include, e.g., phase change thermal batteries and encapsulated thermal batteries. Phase change thermal batteries utilizes a phase change material, e.g., contained in a tank. The phasechange material may advantageously be capable of storing and releasing a significant thermal capacity at the temperature at which the material changes phase. An example of a suitable phase change material is water, which that may be utilized for a thermal energy storage according to an embodiment of the invention of the invention. However, other phase change materials may also be utilized. Moreover, e.g., salts and other materials may be added to the phase change material, e.g., water, to tailor the phase change properties of the particular phase change material according to desired energy storing and release properties of the thermal energy storage. Notice that other materials than water may also be utilized for the thermal energy storage. Encapsulated thermal batteries may also be utilized as thermal energy storage according to an embodiment of the invention. These types of thermal batteries are physically similar to a phase change thermal batteries by utilizing a confined amount of physical material, which is cooled to store thermal energy. However, in a non-phase change encapsulated thermal battery, the temperature of the substance is changed without inducing a phase change. Since a phase change is not needed additional materials may be utilized to store the thermal energy in an encapsulated thermal battery. An advantageous property of the encapsulated thermal battery is its volumetric heat capacity (VHC), also termed volume-specific heat capacity. Non-limiting examples of suitable substances that may be utilized for embodiments of thermal energy storages utilizing these types of thermal batteries may include water, concrete, and wet sand.

[0020] The thermal energy storage may be scaled according to the cooling requirements of the hydrogen refueling station. The cooling requirement may depend on various parameters, including the utility of the expected utility of the hydrogen refueling station, the hydrogen mass flow rate of hydrogen during fueling, the number of dispensers of the station, the humidity and temperature of the climate in which the hydrogen refueling station is located etc. Thus, the hydrogen refueling station may in some embodiments comprise a plurality of thermal energy storages and / or each thermal energy storage may comprise a plurality of thermal batteries. Notice that the thermal energy storage may typically be insulated so that the thermal energy storage does not heat up too fast and thereby loses its cooling capacity too fast. Various types of insulation may be utilized. Moreover, the thermal energy storage may be arrangedunderground or in the ground, to utilize the ground as insulating material, and to potentially avoid direct sun exposure of the thermal energy storage. Direct sun exposure may also be achieved by different forms of reflective shielding of the thermal energy storage.

[0021] In the context of the invention, a controller may be understood to include various types of controllers. The controller may typically comprise a processor and memory. The controller may further comprise inputs for receiving input signals from sensors, and / or other components of the hydrogen refueling station and / or of the cooling system, including, e.g., inputs from one or more ambience parameter sensor(s). The controller may further comprise outputs through which the controller may communicate with components of the cooling system and / or of the hydrogen refueling station, including communications with, e.g., valves, compressors, dispenser, etc. Altogether the input and outputs may be considered included in a communication link, sometimes referred to as communication line, through which the controller may communicate with components of the hydrogen refueling station including the cooling system. The controller may also be configured to communicate with external components, including components of a vehicle connected to the hydrogen refueling station. Notice that the hydrogen refueling station including the cooling system may comprise more than one controller, and that the controllers may communicate. Communication may typically be performed via a wired connection; however, it may also be via a wireless connection. Wireless connections may include various different types of wireless connections, including the following non-limiting examples: WI-FI, Bluetooth, nearfield etc. Furthermore, a controller may also be understood in a broad sense to include one or more sensor(s) connected to one or more valves to control valves. E.g. an ambience sensor may be connected to a valve, and the valve may be configured to open based on an ambience condition and based on an ambience parameter received from the sensor. In the context of the invention, this may be understood as a controller, e.g., valve control.

[0022] The term ambience parameter (sometimes referred to as ambient parameter) may in the context of the invention be relate to any parameter directly or indirectlyassociated with the environment in which the hydrogen refueling station is located. This may, e.g., include one or more of the following non-limiting examples including the humidity, the ambience temperature, the rate of change in the ambience temperature, the rate of change in humidity, the ambience pressure, etc. In principle other parameters may be indirectly associated with the ambient condition or in which the cooling system or hydrogen refueling station is located. Such parameters may include, e.g., pressures and temperature of a coolant in one or more cooling loops of the hydrogen refueling station, the rate of change of the temperature of the coolant of a cooling loop, a pressure measured in the cooling system, a temperature of said thermal energy storage, etc. Notice that parameters related to station components or fluids may be affected by the environment in which the hydrogen refueling station is located. Hence, these parameters indirectly associated with the ambience may be suitable for use as ambience parameter or ambience condition if sufficiently affected by the ambience conditions in which the station is located. However, preferable ambience parameters may be parameters directly associated with the ambience or the environment in which the hydrogen refueling station is located.

[0023] The ambience parameter may be obtained from sensor measurements from, e.g., one or more ambience sensor(s), including, e.g., humidity sensors, temperature sensors, pressure sensors etc. However, ambience parameter(s) may also be obtained from external sources, including from external ambience parameter sensors. Optionally, the ambience parameter may also be obtained from the internet, e.g., from whether reports. E.g., when the ambience parameter is an ambience temperature, the ambience temperature may be obtained from online local whether reports or from one or more centralized data servers receiving, e.g., ambience temperature measurements from sensors positioned at locations near the hydrogen refueling station. Hence, the hydrogen refueling station does not necessarily require a sensor (ambience parameter sensor) to obtain the ambience parameter.

[0024] The term ambience condition (sometimes referred to as ambient condition) may in the context of the invention be understood as a condition related to the ambience milieu in which the hydrogen refueling station including the cooling systemis located. E.g., an ambience condition may include conditions related to temperature, pressure, humidity, time, weather conditions etc. The first ambience condition may be based on the same parameter as the second ambience condition, however, the first and the second ambience conditions may also be based on different parameters. An ambience condition may comprise a threshold value of a parameter, such as, e.g., those mentioned above. An ambience condition may thus, e.g., be one threshold value or it may be a plurality of threshold values.

[0025] In the present context an ambience parameter satisfying an ambience condition, e.g., an ambience parameter satisfying a first ambience condition and / or a second ambience condition, may be understood in different ways. E.g., an ambience parameter may be represented as a value such as a numerical value, and the ambience parameter may be said to satisfy an ambience condition when the value of the ambience parameter is equal to or is crossing the ambience condition and wherein the ambience condition is represented as a value, e.g., a numerical value. An ambience parameter crossing a value of an ambience condition may refer to the value of an ambience parameter exceeding the value of the ambience condition, or to the value of the ambience parameter crossing from higher values to a value below the value of the ambience condition. The ambience condition may thus be understood as a threshold, e.g., a threshold value. However, the ambience condition may comprise multiple thresholds, e.g., threshold values, e.g., values for pressure, temperature, humidity etc., to name a few non-limiting examples. To satisfy an ambience condition comprising a plurality of thresholds for different types of ambience parameters, the corresponding ambience parameters may satisfy each of the plurality of thresholds, e.g., by being equal to the threshold or by crossing the value of the threshold. However, it may also be required to only satisfy one of the plurality of thresholds, depending on the implementation of the invention. As mentioned, ambience condition(s) and ambience parameter(s) may be represented as numerical values. Nevertheless, it is within the scope of the invention to utilize different ways of representing ambience conditions(s) and ambience values(s), including, e.g., vector representation, matrix representation etc. Furthermore, it is within the scope of the invention to utilize different ways or methods to compare an ambience parameter with a corresponding ambience conditionto check if an ambience parameter satisfies an ambience condition. In some embodiments of the invention, the first ambience condition and the second ambience condition may each specify a threshold value of the same parameter. According to an embodiment of the invention, the threshold value of the first ambience condition and of the second condition may be the same threshold value, however, the first ambience condition may specify an ambience condition below the threshold value, while the second ambience condition may specify an ambience condition being above or equal to the threshold value.

[0026] According to an embodiment of the invention, said one or more ambience parameter(s) includes a temperature and wherein said first ambience condition includes temperatures below a temperature threshold.

[0027] Advantageously, this may have the effect that when to use the dry cooler may be based on the ambience temperature. This may be advantageous because the dry cooler is configured to dissipate heat to the ambience. Hence, using the dry cooler for cooling in conditions where the ambience temperature is below an ambience temperature threshold may be advantageous, in that the dry cooler may be used when the dry cooler operates most efficiently. The ambience temperature threshold may vary depending on, e.g., which type of dry cooler that is used. Desired operational efficiency of the dry cooler etc.

[0028] According to an embodiment of the invention, said temperature threshold is below 50 degrees Celsius, such as below 45 degrees Celsius, such as equal to or below 40 degrees Celsius.

[0029] According to an embodiment of the invention, said temperature is an ambience temperature and / or a coolant temperature of a coolant in said third cooling loop.

[0030] Advantageously, the coolant temperature of a coolant in, e.g., the third cooling loop may change with the ambience temperature during operation of the cooling system. E.g., when the ambience temperature increases, the temperature of coolant in the third cooling loop may correspondingly increase, because the dry coolermay not be able to cool the coolant sufficiently. Thereby, the coolant temperature in the third cooling loop may advantageously be utilized as an ambience parameter, according to an embodiment of the invention.

[0031] According to an embodiment of the invention, said one or more ambience parameter(s) include an ambience temperature, and wherein said first ambience condition includes ambience temperatures below a first ambience temperature threshold.

[0032] Advantageously, this may have the effect that the temperature may be used to determine when to open the valve of the third cooling loop to establish a coolant flow in the third cooling loop, and thereby determine when to utilize the dry cooler to provide cooling to the chiller.

[0033] In the context of the invention, the ambience temperature may be understood to include indirect measures of the ambience temperature. E.g., ambience temperature may include temperature of coolant in the third cooling loop, because the dry cooler may not cool to temperatures below the ambience temperature, and hence, when the ambience temperature rises, the temperature of coolant in the third cooling loop, which is cooled by the dry cooler, may rise in correlation with the ambience temperature. Thereby, the temperature of coolant in the third cooling loop may be understood as an indirect measure of the ambience temperature.

[0034] According to an embodiment of the invention, said one or more ambience parameter(s) include a coolant temperature, and wherein said first ambience condition includes coolant temperatures below a first coolant temperature threshold.

[0035] Advantageously, the coolant temperature of a cooling loop may change with the ambience temperature. E.g., when the ambience temperature increase, the coolant temperature may at some point start to increase in parallel. Thereby, coolant temperatures below a first coolant temperature threshold may advantageously be utilized together with the first ambience condition to determine when to utilize the dry cooler. Coolant temperature may, e.g., be measured in the third cooling loop utilizinga temperature sensor. A Coolant temperature measured in said third cooling loop may be understood as an indirect measure of ambience temperature.

[0036] According to an embodiment of the invention, said one or more ambience parameter(s) include an ambience temperature, and wherein said second ambience condition includes ambience temperatures equal to or above a second ambience temperature threshold.

[0037] Advantageously, this may have the effect that the ambience temperature may be used to determine when to open the valve of the fourth cooling loop, and thereby determine when to utilize the thermal energy storage for providing cooling to the chiller and thereby for cooling the hydrogen flowing in the flow path indirectly via the chiller, the first cooling loop and the first heat exchanger. Thereby, the thermal energy storage may be reserved for situations where the ambience temperature is above the second ambience temperature threshold, which is advantageous. This may be particularly advantageous when the hydrogen refueling station is located in hot climate conditions.

[0038] An ambience temperature may be understood as a temperature associated with the temperature in the surroundings in which the hydrogen refueling station is located.

[0039] According to an embodiment of the invention, said one or more ambience parameter(s) include a coolant temperature, and wherein said second ambience condition includes coolant temperatures equal to or above a second ambience temperature threshold.

[0040] Advantageously, this may have the effect that when a coolant temperature rises above to or above the ambience temperature threshold, the thermal energy storage may be utilized for cooling. This is advantageous, because a rising coolant temperature may indicate that, e.g., the dry cooler is not cooling sufficiently, e.g., due to high ambience temperatures.

[0041] According to an embodiment of the invention, said coolant temperature is a temperature of coolant in said third cooling loop.

[0042] Obtaining the coolant temperature from coolant of the third cooling loop may be advantageous, because the temperature of coolant circulating in the third cooling loop may change with the ambience temperature and may further indicate when the dry cooler is no longer able to cool the coolant sufficiently. When this occur, the thermal energy storage may advantageously be utilized for cooling.

[0043] According to an embodiment of the invention, said second ambience temperature threshold is lower than said first ambience temperature threshold.

[0044] Advantageously, this may have the effect that the cooling system may utilize both the thermal energy storage and the dry cooler at ambience temperatures that lies in a range between the second ambience temperature threshold and the first ambience temperature threshold. This may increase the cooling capacity at this temperatures range, while ensuring that the dry cooler is not utilized at ambience temperatures wherein the dry cooler is not able to provide cooling.

[0045] According to an embodiment of the invention, said hydrogen refueling station comprises one or more ambience parameter sensor(s) configured to measure said one or more ambience parameter(s);

[0046] In the context of the invention, an ambience parameter sensor may be understood as a sensor configured to measure one or more parameters associated with the surroundings in which the hydrogen refueling station is located or parameters that is indirectly associated with the surroundings of the hydrogen refueling station. Such parameters indirectly associated with the surroundings of the hydrogen refueling station may comprise parameters related to, e.g., coolant of the cooling system. E.g. the temperature of the coolant may depend on the temperature, humidity etc. of the surroundings of the hydrogen refueling station. Non-limiting examples of ambience parameter sensor(s) include a temperature sensor, a pressure sensor, a humidity sensor. Notice that other sensors than the mentioned may also be applied as ambience parameter sensors. Notice that the hydrogen refueling station may comprise more thanone ambience temperature sensor, according to an embodiment of the invention. Notice that an ambience parameter sensor may include sensors that measure ambience parameters directly and parameters that measure an ambience parameter indirectly. An example of an indirect parameter may, e.g., be a temperature of a coolant that may be at least partly correlated with the ambience temperature.

[0047] According to an embodiment of the invention, said one or more ambience parameter sensor(s) includes a temperature sensor arranged to measure said ambience temperature.

[0048] Advantageously, this enables controlling the use of the thermal energy storage for cooling and potentially also the buildup of the thermal energy storage, according to ambience temperature measured using one or more temperature sensors configured to measure the ambience temperature.

[0049] The temperature sensor may be positioned so that it is able to measure the ambience temperature, e.g., the temperature of the surroundings of the hydrogen refueling station.

[0050] According to an embodiment of the invention, said one or more ambience parameter sensor(s) includes a temperature sensor arranged to measure a temperature of coolant.

[0051] According to an embodiment of the invention, said temperature sensor arranged to measure a temperature of coolant is arranged to measure a temperature of coolant in said third cooling loop.

[0052] This may be advantageous, because the temperature of coolant in the third cooling loop may indicate if the dry cooler is cooling or if the ambience temperature has risen to a level at which the dry cooler may no longer provide sufficient cooling.

[0053] According to an embodiment of the invention, said controller controls said valve of said third cooling loop to a closed state when said one or more ambience parameter(s) does not satisfy said first ambience condition.

[0054] Advantageously, this may have the effect that coolant is not circulated in the third cooling loop, e.g., during higher ambience temperatures, whereat the dry cooler may not be able to sufficiently cool the coolant. Further advantageously, when the thermal energy storage is utilized for cooling, terminating the flow in the third cooling loop may be advantageous in that it minimizes thermal energy transfer to coolant in the third cooling loop from the thermal energy storage, when the thermal energy storage is used for cooling via the chiller.

[0055] According to an embodiment of the invention, said controller controls said valve of said fourth cooling loop to a closed state when said one or more ambience parameter(s) does not satisfy said second ambience condition.

[0056] According to an embodiment of the invention, a lag period (sometimes referred to as a hysteresis) may be implemented starting from the first time the controller changes state of a valve. In the lag period, the controller may not change the state of the valve. This may advantageously hinder a situation where a valve changes state relatively and inexpediently fast, in response to an ambience condition changing relatively fast.

[0057] According to an embodiment of the invention, said chiller is thermally connectable to said thermal energy storage via a fifth cooling loop configured to circulate a coolant flow of cooled down coolant from the chiller to the thermal energy storage, and wherein said fifth cooling loop comprises a fourth valve.

[0058] Advantageously, this enables buildup of the thermal energy storage, by enabling the cooled down coolant to flow from the chiller to the thermal energy storage when the fourth valve is open. Closing the valve may advantageously stop the circulation in the fifth cooling loop.

[0059] According to an embodiment of the invention, said controller is configured to establish a buildup of said thermal energy storage by controlling said fourth valve of said fifth cooling loop to an open state to establish a coolant flow of cooled down coolant from said chiller to said thermal energy storage via said fifth cooling loop.

[0060] Advantageously, this has the effect that the thermal energy storage is cooled by the chiller and thereby a thermal energy storage may be established or reestablished.

[0061] I the context of the invention a buildup of the thermal energy storage may be understood as the thermal energy storage being cooled and the cooling being stored by the thermal energy storage. The cooling of the thermal energy storage may sometimes result in a phaseshift of the material used for the thermal energy storage. E.g., if water is utilized for thermal energy storage, the liquid water may become ice (a solid) when the water is cooled to a temperature below the melting point of the water.

[0062] According to an embodiment of the invention, said first cooling loop comprises a first valve V1, and wherein said controller is configured to establish a buildup of said thermal energy storage by controlling said fourth valve of said fifth cooling loop to an open state and further controlling said first valve of said first cooling loop to a closed state to establish a coolant flow of cooled down coolant from said chiller to said thermal energy storage via said fifth cooling loop, while terminating a coolant flow in said first cooling loop.

[0063] Advantageously, this may have the effect that the thermal energy storage is cooled by the chiller and thereby a thermal energy storage may be established. The closing of the first valve V1 of the first cooling loop may have the effect that coolant is not circulated in the first cooling loop, thereby the cooling capacity of the chiller is not utilized for cooling coolant of the first cooling loop, and thereby the energy storage may be buildup at a faster rate, which is advantageous.

[0064] According to an embodiment of the invention, said controller is configured to establish a buildup of said thermal energy storage by controlling said fourth valve of said fifth cooling loop to an open state, and further by controlling said valve of said third cooling loop to an open state, and further controlling said first valve of said first cooling loop to a closed state to establish a coolant flow in said third cooling loop, and to establish a coolant flow of cooled down coolant from said chiller to said thermal energy storage via said fifth cooling loop, and to terminate a coolant flow in said first cooling loop.

[0065] Advantageously, opening the valve of the third cooling loop enables the dry cooler to provide cooling for the chiller unit, and thereby providing cooling of the thermal energy storage to via the fifth cooling loop, to reestablish or establish the thermal energy storage.

[0066] According to an embodiment of the invention, said controller is configured to establish said buildup of said thermal energy storage only when said hydrogen refueling station is not performing a refueling via said flow path.

[0067] Advantageously, this may have the effect that the cooling system, including the thermal energy storage, may be utilized for cooling hydrogen in said flow path when the hydrogen refueling station is utilized for refueling, instead of utilizing cooling capacity for building or reestablishing the thermal energy storage.

[0068] According to an embodiment of the invention, said controller is configured to establish a buildup of said thermal energy storage when at least one ambience parameter of said one or more ambience parameter(s) satisfies a thermal energy storage buildup condition.

[0069] Advantageously, this provides a parameter-based way of automatically controlling when to establish buildup of the thermal energy storage.

[0070] According to an embodiment of the invention, said at least one ambience parameter of said one or more ambience parameter(s) is an ambience temperature and wherein said thermal energy storage buildup condition includes ambience temperatures below a third ambience temperature threshold.

[0071] Advantageously, this may have the effect that the buildup of the thermal energy storage is performed when the ambience temperature is sufficiently low to enable efficient buildup of the thermal energy storage. E.g., when the ambience temperature drops below the ambience temperature threshold, e.g., during the evening and in particular during the night, the thermal energy storage may be buildup (sometimes referred to as reestablished). Advantageously, the utilization of hydrogen refueling stations are typically low during the evening and particularly during night,and hence, this is an advantageous time to reestablish the thermal energy storage, as this enables the capacity of the refueling station to be utilized for reestablishment of the thermal energy storage instead of it being used for cooling during frequent refueling.

[0072] In the context of the invention, ambience temperature should be understood as a temperature that reflects the temperature of surroundings in which the hydrogen refueling station is located.

[0073] It should be understood that when the ambience temperature is below the third ambience temperature threshold, the thermal energy storage buildup condition may be understood to be satisfied, according to an embodiment of the invention.

[0074] According to an embodiment of the invention, said first ambience temperature threshold is withing the range of 25 degrees Celsius to 45 degrees Celsius, such as within the range of 30 degrees Celsius to 45 degrees Celsius, such as within the range of 35 degrees Celsius to 42 degrees Celsius, such as withing the range of 38 degrees Celsius to 40 degrees Celsius, such as preferably 40 degrees Celsius.

[0075] Advantageously, the dry cooler may provide efficient cooling at temperatures being, e.g., below these mentioned temperature thresholds.

[0076] According to an embodiment of the invention, said second ambience temperature threshold is withing the range of 25 degrees Celsius to 45 degrees Celsius, such as within the range of 30 degrees Celsius to 45 degrees Celsius, such as within the range of 35 degrees Celsius to 42 degrees Celsius, such as withing the range of 38 degrees Celsius to 40 degrees Celsius, such as preferably 40 degrees Celsius.

[0077] Advantageously, the thermal energy storage may be utilized for cooling at temperatures, e.g. at or above these mentioned temperature thresholds. This may be advantageous, since the dry cooler may not be able to provide sufficient cooling at higher ambience temperatures.

[0078] According to an embodiment of the invention, said third ambience temperature threshold is equal to said first ambience temperature threshold.

[0079] According to an embodiment of the invention, said third ambience temperature threshold is equal to or below 48 degrees Celsius, such as equal to or below 44 degrees Celsius, such as equal to or below 42 degrees Celsius, such as equal to or below 40 degrees Celsius, such as equal to or below 38 degrees Celsius, such as equal to or below 35 degrees Celsius, such as equal to or below 32 degrees Celsius, such as equal to or below 29 degrees Celsius.

[0080] Advantageously, the thermal energy storage may be efficiently buildup / reestablished by, e.g., the dry cooler, when the temperature is below the above-mentioned temperature thresholds.

[0081] According to an embodiment of the invention, said chiller comprises a second cooling loop, said second cooling loop comprising a first supplementary heat exchanger and a second supplementary heat exchanger, and wherein said first supplementary heat exchanger is fluidly connected to said second supplementary heat exchanger, and wherein said chiller is thermally connected to said first cooling loop via said first supplementary heat exchanger.

[0082] Advantageously, this this may enable the chiller to cool hydrogen flowing in the flow path via the first cooling loop and via the first heat exchanger. Further advantageously, heat transferred to the second cooling loop from the first cooling loop may be dissipated from the second cooling loop via the second supplementary heat exchanger.

[0083] According to an embodiment of the invention, said second supplementary heat exchanger is thermally connectable to said dry cooler via a third cooling loop.

[0084] Advantageously, this may have the effect that the dry cooler may be utilized to cool hydrogen flowing through the first heat exchanger, by cooling coolant flowing in the second cooling loop, via the third cooling loop and the second supplementary heat exchanger. In other words, heat transferred from the first cooling loop to the second cooling loop of the chiller may be transferred from the second cooling loop to the third cooling loop via the second supplementary heat exchanger, and thereby, thedry cooler may advantageously provide indirect cooling of hydrogen flowing through the first heat exchanger.

[0085] According to an embodiment of the invention, said second supplementary heat exchanger is thermally connectable to said thermal energy storage via a fourth cooling loop.

[0086] Advantageously, this may have the effect that the thermal energy storage may cool the coolant flowing in the second cooling loop and thereby provide cooling for hydrogen flowing in the flow path via the first heat exchanger. Cooling using the thermal energy storage may be particularly advantageous when the ambient temperature is high, as high ambient temperature diminishes the cooling efficiency of the dry cooler or potentially hinder cooling with the dry cooler.

[0087] According to an embodiment of the invention, said first supplementary heat exchanger is thermally connectable to said thermal energy storage via a fifth cooling loop comprising a valve.

[0088] Advantageously, this may have the effect of enabling buildup of the thermal energy storage using the chiller by providing cooling to the thermal energy storage via coolant circulating in the fifth cooling loop.

[0089] According to an embodiment of the invention, said controller is configured to close said fourth valve of said fifth cooling loop when said one or more ambience parameter(s) does not satisfy said thermal energy storage buildup condition or when said hydrogen refueling station is performing a refueling via said flow path.

[0090] According to an embodiment of the invention, said first supplementary heat exchanger is an evaporator.

[0091] According to an embodiment of the invention, said second supplementary heat exchanger is a condenser.

[0092] According to an embodiment of the invention, said thermal energy storage comprises a tank including a phase change material.

[0093] This is advantageous, because a phase change material may be able to absorb and store large amounts of thermal energy.

[0094] A phase change material may release or absorb high amounts of energy during a phase transition. This may advantageously be utilized in the cooling system of the invention for cooling and for efficient thermal energy storage. When a phase change material undergoes a transition between, e.g., the first two fundamental states of matter; solid and liquid, the energy released or absorbed during this transition may be significantly higher than the sensible heat exchange, which is advantageous in the context of the invention.

[0095] According to an embodiment of the invention, said phase change material has a melting point within a temperature range of minus 20 degrees Celsius to 40 degrees Celsius, such as withing the range of minus 15 degrees Celsius to thirty degrees Celsius, preferably minus 5 degrees Celsius to 5 degrees Celsius, such as substantially 0 degrees Celsius.

[0096] Advantageously, this may provide a high thermal energy release or absorption, respectively, at the abovementioned temperatures, due to a phase change, which may be advantageous with respect to operation of a cooling system of the invention, and with regards to the temperatures at which the cooling system may operate.

[0097] According to an embodiment of the invention, said phase change material is water.

[0098] Advantageously, this may be advantageous in that the phase change properties of water may enable water to change phase at suitable pressure and temperature with regards to cooling and storing thermal energy in the cooling system of the invention.

[0099] The thermal energy storage may be a container such as a tank. The tank may comprise a phase change material in addition to pipes wherein, e.g., a coolant may circulate. When using the thermal energy storage for cooling, the coolant may becirculated through the thermal energy storage and the coolant may dissipated heat from the coolant to the phase change material of the thermal energy storage. During buildup of the thermal energy storage, cooled coolant may be circulated through the pipes of the thermal energy storage. The coolant may be cooled by the chiller and may be circulated through the fifth cooling loop from the chiller to the thermal energy storage and through the pipes of the thermal energy storage and then back to the chiller, and thereby the coolant may cool the thermal energy storage, e.g., the phase change material, and thereby buildup the thermal energy storage. When a phase change material is utilizes for the thermal energy storage, the phase change material may change phase from liquid phase into solid phase or vice versa. Other types of suitable thermal energy storages include, e.g., a block of metal, e.g., an aluminum block or similar, which may be cooled in a similar way to establish a thermal energy storage.

[0100] According to an embodiment of the invention, a cooling capacity of said thermal energy storage is at least 300 kWh, such as within the range of 300kWh to 1300kWh, such as withing the range of 400kWh to 1000 kWh, such as within the range of 500kWh to 700kWh.

[0101] This is advantageous, in that this may ensure that the cooling capacity is sufficient for use with a hydrogen refueling station.

[0102] According to an embodiment of the invention, said cooling system comprises a precooling stage comprising: a precooling heat exchanger thermally connected to a second part of said flow path; a precooling loop configured to conduct a coolant flow, and wherein said thermal energy storage is thermally connectable to said precooling heat exchanger via said precooling loop.

[0103] According to an embodiment of the invention, said second part of said flow path is located upstream said first heat exchanger.

[0104] Advantageously, this may enable the thermal energy storage to be utilized for cooling hydrogen in the flow path using the precooling heat exchanger before the hydrogen is cooled via the first heat exchanger. Furthermore, the thermal energy storage may thereby advantageously be applied to cascade the temperature of thehydrogen to a lower level before the hydrogen is cooled via the first heat exchanger, resulting in a lower load on the cooling system, e.g., on the chiller. This may facilitate reduced power consumption, improve daily coefficient of performance of the cooling system and furthermore, this may enable a reduction in the needed size and / or cooling capacity of the chiller and heat exchangers of the cooling system.

[0105] According to an embodiment of the invention, said cooling system comprises a post-cooling stage comprising a post-cooling loop configured to conduct a coolant flow, wherein said post-cooling loop comprises a refrigerant unit and a post-cooling heat exchanger thermally connected to a third part of said flow path and wherein said post-cooling heat exchanger and said refrigerant unit is thermally connectable via said post-cooling loop.

[0106] Advantageously, this enables the cooling system to cool the temperature of the hydrogen even further down. E.g., by first cooling the hydrogen using the first heat exchanger, and then cooling the hydrogen further using the post-cooling stage. In principle, the post-cooling stage may also be implemented to cool the hydrogen in the flow path before cooling the hydrogen via the first heat exchanger and potentially, the post-cooling stage may also be applied to cool hydrogen in the flow path before the hydrogen is cooled using a pre-cooling stage, according to an embodiment of the invention.

[0107] According to an embodiment of the invention, said refrigeration unit is thermally connected to said chiller via a sixth cooling loop to enable cooling of refrigerant circulating in said refrigeration unit by the chiller.

[0108] Advantageously, this may enable the refrigeration unit to be cooled by the dry cooler and / or by the thermal energy storage, e.g., depending on the one or more ambience parameter(s) and the associated first ambience condition and second ambience condition.

[0109] According to an embodiment of the invention, said refrigeration unit is cooled by said thermal energy storage, when said ambience parameter satisfies said second ambience condition. This may be achieved, e.g., by establishing a coolant flow in saidsixth cooling loop and in said fifth cooling loop, e.g., by opening a valve of said sixth cooling loop. The valve may be controlled by the controller.

[0110] According to an embodiment of the invention, said refrigeration unit is cooled by said dry cooler when said ambience parameter satisfies said first ambience condition. This may be achieved, e.g., by establishing a coolant flow in said sixth cooling loop and in said third cooling loop, e.g., by opening a valve of said sixth cooling loop and by opening a valve of said third cooling loop. The valves may be controlled by the controller.

[0111] According to an embodiment of the invention, said refrigeration unit is using carbon dioxide as a refrigerant.

[0112] Advantageously, Carbon dioxide may have several desirable thermo-physical properties making it a good refrigerant with high heat exchange properties. E.g., carbon dioxide may have an excellent heat transfer coefficient, a high energy content, it may be relatively insensitive to pressure losses, and it has a very low viscosity of the liquid phase. Hence, a carbon dioxide-based refrigeration unit may deliver a high cooling performance in a cooling system, which is advantageous.

[0113] According to an embodiment of the invention, said third part of said first flow path is located downstream said first heat exchanger.

[0114] According to an embodiment of the invention, said post-cooling loop comprises a post-cooling valve, and wherein said controller is configured to open said post-cooling valve when a post-cooling parameter satisfies a post-cooling condition.

[0115] Advantageously, this enables the post-cooling loop only to be used if additional cooling is required. E.g., in some refueling situations, the hydrogen may be sufficiently cooled by the cooling system via the first heat exchanger, hence, advantageously, the post-cooling stage may not be utilized, e.g., by closing the post- cooling valve. Alternatively, the pre-cooling stage, e.g., the pre-cooling heat exchanger may be bypassed by applying a bypass conduit to the flow path conducting the hydrogen flow. The bypass conduit may thus be arranged to bypass the post-cooling heat exchanger, according to an embodiment of the invention. According to an embodiment of the invention, said post-cooling parameter may be temperature.

[0116] According to an embodiment of the invention, said cooling system is configured for cooling an average hydrogen flow through said flow path of at least 6.5kg / min.

[0117] Advantageously, this enables fast refueling of vehicles. Including fast refueling of high-capacity vehicles such as, e.g. trucks, trains or ships, to name a few non-limiting examples. Notice that the average hydrogen flow through the flow path may range from 1 kg / min to 6.5 kg / min. or even higher. E.g., a flow of 6.5 kg / min or above may typically be used for filling high-capacity vehicles such as, e.g. trucks, trains, or ships, to name a few non-limiting examples.

[0118] According to an embodiment of the invention, said coolant is an antifreeze liquid.

[0119] Advantageously, this has the effect that the coolant may circulate in the coolant loops at the operating temperatures of the cooling system.

[0120] In the context of the invention antifreeze may be understood as the coolant not freezing within the operating temperatures. E.g., not freezing at temperatures down to substantially minus 40 degrees Celsius.

[0121] According to an embodiment of the invention, said coolant include ethylene glycol-based coolant or a propylene glycol-based coolant.

[0122] Advantageously, this has the effect that the coolant may not change to solid phase and thereby may circulate in the coolant loops at the operating temperatures of the cooling system. Using, e.g., an ethyleneglycol solution may ensure that the coolant does not change to solid state due to cold ambient temperatures. An ethyleneglycol solution may ensure that the coolant does not change to a solid stage within its frost protected range, which could be down to minus 50 degrees Celsius.

[0123] The invention further relates to a method of cooling a hydrogen flow, said method comprising: establishing a hydrogen flow from a hydrogen storage to a hydrogen dispenser via a flow path, establishing a coolant flow in a first cooling loop comprising a chiller and a first heat exchanger thermally connected to at least a part of said flow path; obtain one or more ambience parameter(s); determine that said one or more ambience parameter(s) satisfies a first ambience condition and / or a second ambience condition; wherein when said one or more ambience parameter(s) satisfies said first ambience condition establishing a coolant flow in said third cooling loop, said third cooling loop thermally connecting a dry cooler with said chiller; and wherein when said one or more ambience parameter(s) satisfies said second ambience condition establishing a coolant flow in said fourth cooling loop, said fourth cooling loop thermally connecting a thermal energy storage to said chiller.

[0124] The method may have several advantages, including the advantages previously described in relation to the hydrogen refueling station of the invention.

[0125] Notice that coolant flow in cooling loops may be established in various ways, including by opening one or more valve(s) configured to block or enable flow in the cooling loop. The establishment of flows in cooling loops, including the fourth cooling loop and the third cooling loop, may also include activating a pump of the cooling loop, so that the pump circulates coolant in the cooling loop. Thus, pumps (sometimes referred to as coolant pumps) may be activated and deactivated in concert with the valves that may hinder circulation in a cooling loop when closed and enable circulation in the cooling loop when open. Notice that cooling loops are known in the art, and hence, the skilled person know what is required to enable / establish a flow of coolant in a cooling loop.

[0126] According to an embodiment of the invention, wherein a vessel of a vehicle is connected to the dispenser, and wherein the hydrogen flow is established to flow into the vessel of the vehicle.

[0127] According to an embodiment of the invention, said one or more ambience parameter(s) includes a temperature and wherein said first ambience condition includes temperatures below a temperature threshold.

[0128] According to an embodiment of the invention, said one or more ambience parameter(s) includes a temperature and wherein said second ambience condition includes temperatures below a temperature threshold.

[0129] According to an embodiment of the invention, said method is configured to be performed by said hydrogen refueling station.

[0130] In a further aspect, the invention relates to a hydrogen refueling system comprising a hydrogen refueling station according to embodiments of the invention, and further comprising a vehicle connected to said dispenser of said hydrogen refueling station.

[0131] The invention further relates to a use of a hydrogen refueling station according to embodiments of the invention to perform the method according to embodiments of the invention.

[0132] A further aspect of the invention relates to a cooling system for a hydrogen refueling station; the cooling system comprising: a first cooling loop configured to conduct a coolant flow, wherein said first cooling loop comprises a first heat exchanger thermally connectable to at least a part of a flow path configured to conduct a hydrogen flow; a chiller thermally connected to said first heat exchanger via said first cooling loop; a dry cooler thermally connectable to said chiller via a third cooling loop configured to conduct a coolant flow, wherein said third cooling loop comprises a valve; a thermal energy storage thermally connectable to said chiller via a fourth cooling loop configured to conduct a coolant flow, wherein said fourth cooling loop comprises a valve; one or more ambience parameter sensor(s) configured to measure one or more ambience parameter(s); a controller configured to control said valve of said third cooling loop to an open state to establish a coolant flow in said third cooling loop when one or more ambience parameter(s) satisfies a first ambience condition, and thereby thermally connecting said dry cooler to said chiller via said third cooling loop;and wherein said controller is further configured to control said valve of said fourth cooling loop to an open state to establish a coolant flow in said fourth cooling loop when said one or more ambience parameter(s) satisfies a second ambience condition, and thereby thermally connecting said thermal energy storage to said chiller via said fourth cooling loop.The drawings

[0134] For a more complete understanding of this disclosure, the invention is described with reference to accompanying figures comprising illustrative representations of exemplified embodiments of the invention. The figures illustrate different features and different combination of features according to embodiments of the invention. Notice that features presented in different drawings may be combined within the scope of the invention. References are made to the following figures: fig. 1 illustrates a hydrogen refueling station comprising a cooling system according to an embodiment of the invention, fig.2 illustrates a schematical representation of a dry cooler and a chiller with a second cooling loop according to an embodiment of the invention, fig. 3 illustrates a schematical representation of a cooling system operated to cool hydrogen based on a thermal energy storage according to an embodiment of the invention, fig. 4 illustrates a schematical representation of a cooling system operated to reestablish a thermal energy storage according to an embodiment of the invention, fig. 5 illustrates a schematical representation of a hydrogen refueling station with a cooling system having a precooling stage according to an embodiment of the invention, fig. 6 illustrates a schematical representation of a hydrogen refueling station with a cooling system having a post-cooling stage according to an embodiment of the invention, fig. 7 illustrates a hydrogen refueling station with a multistage cooling system having a precooling stage and a post-cooling stage according to an embodiment of the invention.Detailed description

[0135] The following description comprises nonlimiting examples of embodiments of the invention. Details such as specific structures, arrangements and methods are provided to give an understanding of embodiments of the invention. Note that detailed descriptions of well-known methods, systems, apparatuses, circuits, parameters, known sensors, chillers, refrigeration units, components including, e.g., bolts, materials, control leads, etc. have been omitted to not obscure the description of the invention with unnecessary details. Non-limiting examples of such component that will not be described in detail, but which is typically included in hydrogen refueling station and / or cooling system designs include, e.g., means for pressurizing the hydrogen and / or coolant, including, e.g., one or more compressors, expansion valves, evaporators and / or condensers of cooling loops / chillers / refrigeration units, fluid pumps, controllers, etc. Further notice that the invention is not limited to the specific examples described below, and a person skilled in the art may choose to implement the invention in other embodiments without these specific details. E.g., the invention may be utilized in larger refueling station designs, e.g., comprising multiple dispensers, or as part of a larger cooling system of a hydrogen refueling station. Furthermore, a skilled person in the field of the invention may choose to combine features of the described embodiments and of the illustrated embodiments of the invention. As such, the invention may be designed and altered into a multitude of varieties within the scope of the invention, as specified in the claims.

[0136] The following section comprises a description of various embodiments of the invention with references to the figures.

[0137] Fig .1 illustrates a schematical representation of a hydrogen refueling station 1 with a cooling system according to an embodiment of the invention. The hydrogen refueling station 1 comprises a hydrogen storage 2 connected to a hydrogen dispenser 3 via a flow path 4. For illustration purposes, a vehicle 5 is connected to the dispenser 3 of the hydrogen refueling station. The hydrogen refueling station 1 further comprises a cooling system, which is configured to cool hydrogen flowing from the storage to the dispenser via the flow path 4. The cooling system comprises a chiller 25 a first heatexchanger 8, a dry cooler 40, a thermal energy storage 20a, an ambience parameter sensor 44 connected to a controller 22 via a communication line 44. The first heat exchanger 8 is thermally connected to a part of the flow path 4 and further thermally connected to the chiller 25 via a first cooling loop 6. The chiller is also thermally connected to the dry cooler 40 via a third cooling loop 9 having a valve V5, and in addition, thermally connected to the thermal energy storage 20a via a fourth cooling loop 10 having a valve V7. The cooling loops are configured to conduct coolant flow or said differently, configured to circulate a coolant flow, and hence, the cooling loops may transfer thermal energy, e.g., heat, between components of the hydrogen refueling station, via the circulating coolant. The state of the valve V5 of the third cooling loop and state of the valve V7 of the fourth cooling loop is controlled by the controller. The valves may be controlled between an open state and a closed state. When the valves are in the open state, coolant may circulate in the given cooling loops, when the valves are in a closed state, the circulation is hindered by the closed valve. The valves may be controlled independently by the controller 22. In principle, the valves may optionally be connected to the ambience parameter sensor and thereby be controlled according to the output of the ambience parameter sensor. When the valves are directly connected to one or more ambience parameter sensors, the valves may be configured to open when on input from the one or more sensor(s) fulfills the ambience condition. E.g. in an embodiment where a second ambience condition is fulfilled when an ambience temperature is equal to or above a second ambience temperature threshold, the valve may be configured to open when the temperatures are equal to or above the second ambience temperature threshold. Thus, the valves may optionally be configured to change state between an open and a closed state based on a first ambience condition and / or based on a second ambience condition and further based on input from one or more ambience parameter sensor(s),

[0138] In this embodiment, the state of the valves V5 and V7 is controlled by the controller based on a first ambience condition and a second ambience condition and further based on an ambience parameter measured with the ambience parameter sensor. Ambience parameter(s) may be directly related to the surrounding of the hydrogen refueling station or indirectly related to the surrounding of the hydrogenrefueling station. Preferably, ambience parameter(s) directly related to the surroundings of the hydrogen refueling station is utilized. An example of such an ambience parameter is ambience temperature, which is to be understood as the temperature of the surroundings in which the hydrogen refueling station is located. Accordingly, an example of a preferred ambience parameter sensor is a temperature sensor arranged to measure the temperature of the surroundings of the hydrogen refueling station. Various temperature sensors may be utilized. Optionally, the temperature sensor may be arranged such that the sensor is shielded from direct sunlight.

[0139] When an ambience parameter satisfies the first ambience condition, the controller is configured to control the valve V5 of the third cooling loop 9 to an open state, to establish a flow of coolant in the third cooling loop 9. Thereby, a thermal connection is established between the dry cooler 40 and the chiller 25 via the third cooling loop 9. The thermal connection between the dry cooler and the chiller may be understood to involve coolant circulating in the third cooling loop. As such, the chiller 25 and the dry cooler 40 may sometimes be understood as being also fluidly connected or as being included in the third cooling loop 9. When the valve V5 of the third cooling loop 9 is open, heat may thus be exchanged between the dry cooler 40 and the chiller 25 via the coolant circulating in the third cooling loop. The coolant may be different types of coolant, including e.g., ethylene glycol-based coolant or a propylene glycol- based coolant. In this example the coolant is an ethylene glycol-based coolant. Advantageously, coolants with low global warning potential may be used.

[0140] When an ambience parameter satisfies the second ambience condition, the controller is configured to control the valve V7 of the fourth cooling loop 10 to an open state, to establish a flow of coolant in the fourth cooling loop 10. Thereby a thermal connection is established between the thermal energy storage 20a and the chiller, via the fourth cooling loop 10. The thermal connection between the thermal energy storage 20a and the chiller 25 may be understood to involve coolant circulating in the fourth cooling loop 10. As such, the chiller 25 and the thermal energy storage 20a may sometimes be understood as being fluidly connected or as being included inthe fourth cooling loop 10. When the valve V7 of the fourth cooling loop 10 is open, heat may thus be exchanged between the thermal energy storage 20a and the chiller 25 via coolant circulating in the fourth cooling loop 10. This enable the thermal energy storage to be utilized to indirectly cool hydrogen in the flow path 4 via the fourth cooling loop, the chiller, the first cooling loop and the first heat exchanger 8. Cooling based on the thermal energy storage may advantageously be utilized in hot ambience conditions, while cooling based on the dry cooler may be utilized in at less hot ambience conditions.

[0141] Examples of optional suitable ambience parameters and corresponding suitable ambience conditions include the parameter ambience temperature, and a corresponding first ambience temperature threshold and second ambience temperature threshold.

[0142] During operation, the temperature of the liquid coolant circulating in the first cooling loop may, e.g., be within the range of minus 15 degrees Celsius to minus 10 degrees Celsius. However, the temperature in the first cooling loop may be higher or lower. During a fueling, hydrogen entering the first heat exchanger may be, e.g., 20 degrees Celsius. When leaving the first heat exchanger 8, the hydrogen may be cooled to minus 5 degrees Celsius. However, hydrogen may also be cooled to lower temperatures using the first heat exchanger, and the hydrogen may also be warmer than 5 degrees Celsius when leaving the first heat exchanger 8.

[0143] Optionally, the hydrogen refueling station may comprise an ambience temperature sensor (sometimes referred to as a temperature sensor). The ambience temperature sensor may be configured to measure the ambience temperature of the surroundings in which the hydrogen refueling station is located. The ambience temperature sensor is an example of an ambience parameter sensor.

[0144] Optionally, an ambience parameter sensor may be arranged to measure the temperature of the coolant (sometimes referred to as coolant temperature) flowing in the third cooling loop. As the ambience temperature rises, the dry cooler may at some point not be able to sustain cooling of the coolant circulating in the third cooling loop.This causes the temperature of the coolant in the third cooling loop 9 to rise. At some point the coolant temperature may rise above a temperature threshold, e.g., an ambience temperature threshold, and hence, the coolant temperature may be utilized as an ambience parameter. The coolant temperature may, e.g., sometimes be considered and indirect measure of an ambient temperature. The first ambience condition may optionally include coolant temperatures below a first coolant temperature threshold, and the second ambient condition may optionally include coolant temperatures equal to or above a coolant temperature threshold. E.g., the coolant temperature thresholds may be equal to the ambience temperature thresholds or, e.g., the coolant temperature thresholds may be slightly higher, e.g., 5 degrees Celsius higher than the ambience temperature threshold. This is because the coolant in, e.g., the third cooling loop is typically higher than the ambience conditions, because the dry cooler may not be able to cool the coolant to the same temperature as that of the surroundings - the ambient temperature.

[0145] Optionally, the first ambience condition may include ambience temperatures below a first ambience temperature threshold. The first ambience temperature threshold may in this optional embodiment be 39 degrees Celsius. Thus, at temperatures below 39 degrees Celsius, the first ambience condition may be satisfied. Notice that the first ambience temperature threshold may both be higher or lower.

[0146] Optionally, the second ambience condition includes ambience temperatures equal to or above a second ambience temperature threshold. The second ambience temperature threshold may in this optional embodiment be 39 degrees Celsius. Thus, at temperatures equal to or above 40 degrees Celsius, the second ambience condition may be satisfied. Notice that the second ambience temperature threshold may both be higher or lower.

[0147] I the above optional examples, the first and the second ambience temperature thresholds are equal, however, the first and the second ambience temperature conditions are different. In other embodiments of the invention, the first and the second ambience temperature thresholds may be different. E.g., the second ambience temperature threshold may optionally be lower than the first ambience temperaturethreshold. As an example, the first ambience temperature threshold may be 40 degrees Celsius, while the second ambience temperature threshold may be 35 degrees Celsius. This may advantageously, enable simultaneous cooling with the dry cooler and with the thermal energy storage at a temperature range where the first and the second ambience conditions overlap.

[0148] Optionally, the valve V5 of the third cooling loop may be controlled to a closed state by the controller when an ambience parameter does not satisfy the first ambience condition.

[0149] Optionally, the valve V7 of the fourth cooling loop 10 may controlled to a closed state by the controller, when an ambience parameter does not satisfy the second ambience condition.

[0150] Optionally, the first cooling loop may comprise a valve V1. The valve may be used to stop circulation of coolant in the first cooling loop 6. This may advantageously be utilized during buildup of the thermal energy storage 20a.

[0151] Optionally, the hydrogen refueling station may receive one or more ambience parameters from an online source. An example of such an online source includes, e.g., an online server that receives local ambience parameters from local sensors, including sensor located near the hydrogen refueling station. The online source may optionally comprise a local online whether report. The controller may optionally receive ambience temperature via the internet from an online source. When ambiance parameters are received via the internet from an online source or alternatively from external sensors, the hydrogen refueling station may optionally, not comprise an ambience parameter sensor.

[0152] In principle, instead of controlling circulation of coolant in the mentioned cooling loops based on control of valves based on a first and a second ambience condition and based on one or more ambience parameter(s), the circulation may be controlled by activation and deactivation of a circulation pump of each loop. Moreover, it should be understood that circulation pumps or compressors may beoperated and controlled in concert with control of the valves, to establish flow in cooling loops.

[0153] Notice that the chiller typically comprises components such as an evaporator, a compressor a condenser and an expansion valve. These are not illustrated in the figures, to not obscure the figures with unnecessary details.

[0154] In this embodiment, the controller is connected to the ambience parameter sensor via a wired connection - a wired communication line. However, in other embodiments of the invention, the sensor and the controller may communicate via wireless connection. E.g., via a wireless communication line 42.

[0155] Example 1 – Cooling of hydrogen using the chiller and the dry cooler

[0156] In a refueling example, a vehicle 5, e.g., a fuel cell vehicle such as a fuel cell truck or car, is connected to the dispenser of the hydrogen refueling station 1. In this example the ambience parameter is the ambience temperature measured with a temperature sensor arranged to measure the ambience temperature, and the first ambience condition includes ambience temperatures below a first ambience temperature threshold. In this example the first ambience temperature threshold is 40 degrees Celsius, while the second ambience condition includes temperatures equal to or above a second ambience temperature threshold, which in this example is 40 degrees. The refueling of the vehicle is initiated and the ambience temperature measured with the temperature sensor is an ambience temperature of 25 degrees Celsius, and hence, the ambience temperature satisfies the first ambience condition. Thereby, the controller 22 controls the valve V5 of the third cooling loop to an open state, causing coolant to circulate in the third cooling loop 9, in addition to the coolant circulating in the first cooling loop 6. As hydrogen is flowing from the hydrogen storage 2 to the vessel of the vehicle 5 via the flow path 4 and through the first heat exchanger 8, heat from the hydrogen is transferred via the first heat exchanger 8 to coolant of the first cooling loop 6, which flows through the first heat exchanger. This cools the hydrogen. The heated coolant of the first heat exchanger returns to the chiller 25. Via the chiller 25, the heat of obtained by the coolant circulating in the first coolingloop 6 is transfers to the third cooling loop 9. The coolant of the third cooling loop flowing from the dry cooler 40 to the chiller 25 has been cooled by the dry cooler 40, and thereby is able to efficiently obtain the heat originally obtained from the hydrogen. As the heat is transferred from the coolant flowing in the first cooling loop to the coolant circulating in the third cooling loop via the chiller, the coolant in the first cooling loop has thus now been cooled before it returns to the first heat exchanger for cooling hydrogen during the refueling of the vehicle. In essence, the dry cooler is used to provide cooling for the chiller, which cools the coolant of the first cooling loop and thereby provides cooling for the hydrogen in the flow path during a refueling. Example 2 – Cooling of hydrogen using the chiller and the thermal energy storage

[0157] In a further refueling example, a vehicle 5 is connected to the dispenser of the hydrogen refueling station 1. In this example the ambience parameter sensor is a temperature sensor arranged to measure the ambience temperature, and the second ambience condition includes temperatures above an ambience temperature threshold, which in this example is a temperature of 40 degrees Celsius. Refueling of the vehicle is initiated and the measured ambience temperature is 42 degrees Celsius. The controller determines that the ambience temperature of 42 degrees satisfies the second ambience temperature threshold. Thereby, the controller 22 controls the state of the valve V7 of the fourth cooling loop to an open state. Thereby, coolant circulates in the fourth cooling loop 10 and in the first cooling loop 6. As hydrogen flows from the hydrogen storage 2 to the vessel of the vehicle 5 via the flow path 4 and through the first heat exchanger 8, heat from the hydrogen is transferred via the first heat exchanger 8 to coolant of the first cooling loop 6, which flows through the first heat exchanger 8. The heated coolant of the first heat exchanger 8 returns to the chiller 25. Via the chiller 25, the heat obtained by the coolant circulating in the first cooling loop 6 is transfers to the fourth cooling loop 10. The coolant of the fourth cooling loop 10 flowing from the thermal energy storage 20a to the chiller 25 has been cooled by the thermal energy storage 20a, and thereby is able to efficiently obtain the heat originally obtained from the hydrogen. As the heat is transferred from the coolant flowing in the first cooling loop to the coolant circulating in the fourth cooling loop, the coolant in the first coolingloop has thus been cooled before it returns to the first heat exchanger for cooling hydrogen during the refueling of the vehicle. In other words, hydrogen in the flow path 4 is cooled by the thermal energy storage via the fourth cooling loop, 10, the chiller 25 and the first cooling loop 6 and the first heat exchange 8. Dry coolers typically is not able to provide sufficient cooling at higher ambience temperatures such as temperatures, e.g., above 40 degrees Celsius, and hence, cooling using the thermal energy storage at higher temperatures, such as at, e.g., temperatures above 40 degrees Celsius is advantageous.

[0158] Fig. 2 illustrates a schematical representation of a cooling system 38 for cooling when the second ambience condition is satisfied. The cooling system is similar to the cooling system illustrated in fig. 1, except that the cooling system illustrated in fig. 2 do not comprise the thermal energy storage 20a and the fourth cooling loop 10. Also, the cooling system illustrated in fig. 2 illustrates an exploded view of the chiller 25 illustrated in fig. 1. The cooling system 38 may be utilized to cool hydrogen independent of other cooling systems or other cooling system stages. However, the cooling system may also be implemented as a cooling stage in a cooling system comprising a plurality of cooling stages including, e.g., a pre-cooling stage and / or a post-cooling stage. Examples of such cooling systems is illustrated in fig.5, fig.6 and fig 7.

[0159] The cooling system illustrated in fig, 2 comprises a chiller 25 that exploits a dry cooler 40 for cooling. The dry cooler 40 enables this cooling system to provide sufficient cooling for cooling hydrogen during a refueling in surroundings where the temperature may reach 40 degrees Celsius. Nevertheless, this cooling system may typically be implemented for cooling when the surrounding (ambient temperature) is below 40 degrees Celsius or the cooling system may be utilized as a cooling stage in a multistage cooling system comprising further cooling stages or used with a thermal energy storage as described in relation to, e.g., fig. 1. Combining a plurality of cooling stages may advantageously provide sufficient cooling of hydrogen during a refueling even in hot climate where the surrounding temperature may reach temperatures of 40 degrees Celsius or more.

[0160] The cooling system 38 comprises a first heat exchanger 8 configured for cooling hydrogen passing through the first heat exchanger 8, which is part of the flow path 4. Various kinds of heat exchangers may be utilized as the first heat exchanger 8. Examples of suitable heat exchangers are provided elsewhere in this disclosure.

[0161] The cooling system further comprises a first cooling loop 6, a second cooling loop 7 and a third cooling loop 9. The first cooling loop 6 comprises a first flow loop line 19ca that fluidly connects the first heat exchanger 8 to the chiller 25, or more particular, connects the first heat exchanger to a first supplementary heat exchanger 39a. The first supplementary heat exchanger 39a may, e.g., be an evaporator.

[0162] The second cooling loop comprises the first supplementary heat exchanger 39a, a cooling loop compressor 41 and second supplementary heat exchanger 39b being fluidly connected by a second flow loop line 19cb. The second supplementary heat exchanger 39b may, e.g., be a condenser. The chiller 25 may thus be considered to comprise the second cooling loop including the first and the second supplementary heat exchangers and the cooling loop compressor. The second cooling loop may further comprise an expansion valve (not illustrated).

[0163] The third cooling loop 9 comprises a third flow loop line 19cc that fluidly connects the second supplementary heat exchanger 39b and the dry cooler 40. The dry cooler cools the coolant circulating in third cooling loop 9 and thereby provides further cooling to the second cooling loop 7, via the second supplementary heat exchanger 39b. Advantageously, adding the dry cooler 40 to the cooling system may increase the cooling capacity of the cooling system such that the cooling capacity of the system is larger compared to the cooling capacity provided by only the second cooling loop without the dry cooler added. The first supplementary heat exchanger 39a cools the coolant flowing in the first cooling loop 6, and the cooled down coolant of the first cooling loop 6 enters the first heat exchanger 8 and thereby cools hydrogen in the hydrogen pipe 4 via the first heat exchanger 8.

[0164] Fig 3 and fig. 4 illustrates the same cooling system. Notice that figure 3 illustrates an example of cooling hydrogen with the cooling system, whereas fig. 4 illustrates buildup (or reestablishment) of the thermal energy storage. The cooling system comprises a phase change thermal energy storage based on water with a capacity above 300 kWh. However, notice that different types of thermal energy storages may be implemented in the cooling system, including various examples mentioned elsewhere in this disclosure. Further notice that the cooling loops thermally connected to the thermal energy storage, including, e.g., the fourth and the fifth cooling loop may be thermally connected to the energy storing material of the thermal energy storage in various ways, e.g., by use of different types of heat exchangers and heat exchanging methods. Examples of heat exchangers are described elsewhere in this disclosure.

[0165] The cooling capacity of the thermal energy storage may preferably be at least 300 kWh, and typically the capacity may be between 300 kWh to 1200 kWh. However, when the cooling system is implemented on larger hydrogen refueling stations, the cooling capacity of the thermal energy storage may be larger. For smaller hydrogen refueling stations, the cooling capacity may be smaller. The cooling capacity of the thermal energy storage may thus, e.g., be adapted according to the amount of refueling that is performed by a station, and / or according to the number of dispensers that the refueling station include, etc.

[0166] Fig. 3 illustrates a schematical representation of a cooling system 38 with a thermal energy storage 20a according to an embodiment of the invention. The dashed lines indicate that coolant is not circulating in a cooling loop. The cooling system 38 is similar to the cooling system illustrated in fig. 2, with the exception that this embodiment of the cooling system comprises an ambience sensor and a thermal energy storage 20a that may be used for cooling, e.g., during hot ambient temperatures at which the cooling system illustrated in fig. 10 may not provide sufficient cooling capacity. Hence, the cooling system 38 may be considered a variant of the cooling system described in relation to fig. 1, however, with an added fifth cooling loop 11that may be used to establish or reestablish the thermal energy storage 20a. Notice that the chiller is shown in an exploded view similar to the view of the chiller given in fig. 2.

[0167] In addition to the cooling system illustrated in fig. 2, the cooling system 38 illustrated in fig.3 further comprises a thermal energy storage 20a, fluidly connectable to the second supplementary heat exchanger 39b of the chiller 25 via a fourth cooling loop 10 comprising the fourth coolant flow lines 19cd and valve V7 and the optional valve V8. The thermal energy storage 20a is further fluidly connectable to the first secondary heat exchanger 39a of the chiller via a fifth cooling loop 11 comprising the fifth coolant flow lines 19ce and valve v4 and the optional valve v3. The first, second and third coolant flow lines further comprises valves V1-V6.

[0168] Figure 3 illustrates cooling of hydrogen with a cooling system 38 comprising a thermal energy storage 20a, wherein the thermal energy storage 38 is configured for cooling coolant flowing in a second cooling loop 7 via the second supplementary heat exchanger 39b of the chiller. The stipulated lines illustrate flow lines wherein the coolant flow is terminated and / or wherein the cooling loop is inactive.

[0169] In this exemplified embodiment of the invention, the the ambience parameter sensor 22 is considered a temperature sensor arranged to measure an ambient temperature. The controller 43 is configured to determine whether to utilize the thermal energy storage 20a or the dry cooler 40 for cooling, based on the measured ambience temperature and further based on a first ambience condition and a second ambience condition, as described in relation to fig. 1. In this example, the first ambience condition requires that the ambience temperature is below 40 degrees in order for the first ambience condition to be satisfied. The second ambience condition is satisfied when the ambience temperature is equal to or above 40 degrees. Notice that the mentioned temperatures that satisfies the first and second ambience conditions may be higher or lower than the exemplified 40 degrees Celsius, depending on the implementation of the invention.

[0170] In a first example, the ambience temperature measures an ambience temperature of 42 degrees. The controller monitors the ambience temperatures received from the ambience temperature sensor via the communication line 44. Upon receiving the ambience temperature of 42 degrees, the controller 43 determines that the ambience temperature satisfies only the second ambience condition. Hence the controller controls the state of the valves V3, V4, V5, V6 to a closed state, while valves V1, V2 and V7, V8 are controlled to an open state. This enables flow in the fourth cooling loop 10 via the coolant flow lines 19cd from the thermal energy storage 20a to the second supplementary heat exchanger 39b. Furthermore, this also enables flow of coolant in the first cooling loop 6 comprising the coolant flow lines 19ca. Thereby, coolant is circulating to the thermal energy storage 20a where it is cooled and from the thermal energy storage 20a to the second supplementary heat exchanger 39b wherein coolant in the second cooling loop 7 comprising coolant flow lines 19cb is cooled by the coolant cooled in the thermal energy storage 20a. The coolant circulating in the first cooling loop 6 comprising the coolant flow lines 19ca, the first supplementary heat exchanger 39a and the first heat exchanger 8, is cooled by the first supplementary heat exchanger 39a, and thereby is able to cool hydrogen flowing into the first heat exchanger 8 from the flow path 4. This use of the thermal energy storage is advantageous in that it increases the cooling capacity of the cooling system 38. Advantageously, the cooling system may be utilized in conditions where the ambient temperature is, e.g., above 40 degrees Celsius. Advantageously, the dry cooler may be utilized as described in relation to fig.1 and fig.2 for cooling hydrogen during periods of the day (including night, evening, morning etc.) where the ambient temperature is, e.g., below 40 degrease, such as below 38 degrees Celsius, such as below 35 degrees Celsius, such as below 30 degrees Celsius, whereas the thermal energy storage may be utilized for cooling hydrogen as described in relation to fig. 3 during periods where the ambient temperature is above 30 degrees Celsius, such as above 35 degrees Celsius, such as above 38 degrees Celsius, such as preferably above 40 degrees Celsius, such as above 45 degrees Celsius. A controller may control the cooling system 38 according to the ambient temperature and thereby decide whether to use the dry cooler and / or the thermal energy storage for cooling. In some situations, both the dry cooler and the thermal energy storage may be utilized for cooling.

[0171] The thermal energy storage may be rebuilt during low utility periods, e.g., during nighttime, and / or simply, when the cooling system is not applied to cool hydrogen. E.g., when the cooling system is implemented in a hydrogen refueling station, the thermal energy storage may be reestablished in periods where no vehicle is being refueled with the hydrogen refueling station.

[0172] Optionally, in an embodiment of the invention the thermal energy storage 20a may be fluidly connected via coolant flow loop lines to the first supplementary heat exchanger. In this configuration, the thermal energy storage 20a may not necessarily be connected to the second supplementary heat exchanger 20a. further optionally, the thermal energy storage may be directly connected to the heat exchanger 8, to provide cooling of hydrogen in the hydrogen pipe via the heat exchanger 8.

[0173] Optionally, the cooling system may be used as a cooling stage of a multistage cooling system further comprising a pre-cooling stage or a post-cooling stage or both of these two additional cooling stages, including the cooling systems illustrated in fig. 5, fig. 6, and fig.7, respectively.

[0174] Fig. 4 schematically illustrates reestablishment (sometimes referred to as a buildup) of the thermal energy storage 20a of a cooling system 38. The cooling system is substantially identical to the cooling system illustrated in fig. 3 and comprises the same components. The cooling system may be implemented in a hydrogen refueling station like the cooling system illustrated in fig. 1. The dashed lines indicate that coolant is not circulating in a cooling loop.

[0175] The following describes an example of the valve control that is performed to perform the buildup of the thermal energy storage. The valves may be controlled by the controller 43. The controller may initiate the buildup of the thermal energy storage 20a when an ambience parameter satisfies a thermal energy storage buildup condition. In this example, the ambience parameter is ambience temperature, and the thermal energy storage buildup condition is satisfied when the ambience temperature is below 35 degrees Celsius. The ambience temperature is measured with an ambience temperature sensor 22, which in this embodiment of the invention is a temperaturesensor that is part of the hydrogen refueling station. As an example, the ambience temperature is measured with the sensor and provided to the controller via the communication line 44. When the ambience temperature is below 35 degrees Celsius, the thermal energy storage buildup condition is satisfied, and the controller initiates the buildup of the thermal energy storage. The buildup of the thermal energy storage is continued until the thermal energy storage buildup condition is no longer satisfied or until the full capacity of the thermal energy storage has been restored. Initiating the buildup of the thermal energy storage involves initiating circulation of coolant in the fifth cooling loop 11, which involves opening of valves and potentially closing of other valves.

[0176] Optionally, the buildup of the thermal energy storage is performed only when no refueling is performed via the dispenser and the flow path 4. This ensures that the full cooling capacity of the chiller and dry cooler may be utilized for building up (or rebuilding) the thermal energy storage 20a. In this example, the material used for thermal storage in the thermal energy storage is water contained in a tank. Notice that the thermal energy storage may sometimes be referred to as an ice bank or as a thermal buffer. In this example, the thermal energy storage may be considered a phase change thermal energy storage.

[0177] The following includes an example of the valve control performed by the controller when the requirements for initiating the buildup of the thermal energy storage has been satisfied. In this example of valve control performed to reestablish the thermal energy storage, the valves V5, V6, V3, V4 are opened, while the valves V1, V2, V7, V8 are closed. Thereby coolant is circulating in a fifth cooling loop 11 comprising the coolant flow loop lines 19ce, the thermal energy storage 20a and the first supplementary heat exchanger 39a of a chiller 25. Coolant is further circulating in the second cooling loop 7 comprising the second supplementary heat exchanger 39b and the coolant flow lines 19cb and also, coolant is circulating in the third cooling loop 9 comprising the dry cooler 40 and the third coolant flow lines 19cc. Thereby, the thermal energy storage 20a is reestablished based on cooling using the second cooling loop and the dry cooler 40. As previously described, this mode of operation of thecooling system may advantageously be performed during low utility periods of the cooling system. E.g., during the night. Notice, that the dry cooler cools the refrigerant circulating in the second cooling loop 7 of the chiller 25, by circulating cooled down coolant in the third cooling loop. The refrigerant circulating in the second cooling loop is thereby cooled via the second supplementary heat exchanger 39b. The cooled down refrigerant leaves the second supplementary heat exchanger 39b and enters the first supplementary heat exchanger 39a. As the coolant circulating in the fifth cooling loop 11 also enters the first supplementary heat exchanger 39a, it is cooled down by the cooled down refrigerant of the second cooling loop 7. The cooled coolant of the fifth cooling loop 11 then returns to the thermal energy storage, to provide cooling for the thermal energy storage via a thermal connection to the material of the thermal energy storage used to store the cooling, which in this embodiment is water based. The thermal connection between the coolant of the fifth cooling loop and the water of the thermal energy storage may be established in various ways. E.g., the fifth cooling loop (an in also the fourth cooling loop) may be arranged to continue inside the water tank of the thermal energy storage as a coiling conduit, wherein the coolant is conducted. The coil ensures a larger area for heat exchange between the coolant and the water in the thermal energy storage. Nevertheless, various other ways of providing efficient heat exchange between the two materials may be utilized to provide the thermal connection to cool the thermal energy storage. This may include different types of heat exchangers and heat exchanging methods. Different types of thermal energy storages may be implemented in the cooling system, including various examples mentioned elsewhere in this disclosure.

[0178] Notice that the illustrated cooling systems are not limited to the use of specific types of heat exchangers and thermal energy storage. Further notice that the thermal energy storage may comprise further serially or parallelly coupled thermal energy storages.

[0179] Notice that circulation pumps and / or compressors are not illustrated, as the skilled person would know how to implement these components in the system whererelevant, e.g., for circulating coolant in coolant flows, and for pressurizing refrigerant in the chiller etc.

[0180] Optionally, the buildup of the thermal energy storage may be performed when the ambience temperature is below a third ambience temperature threshold. The third ambience temperature may optionally correspond to the first ambience temperature threshold. However, the third ambience temperature threshold may also be different from the first ambience temperature threshold. Advantageously, the buildup of the thermal energy storage may thereby be controlled independent of the first ambience temperature threshold, which determines, e.g., when to use the dry cooler for cooling. E.g., the third ambience temperature threshold may be lower than the first ambience temperature threshold, in which case, the buildup of the thermal energy storage may only be reestablished at ambience temperatures that is even lower than the temperatures specified by the first ambience temperature threshold. This may have the effect that the thermal energy storage is established at temperatures where the dry cooler may cool more efficiently, which is advantageous.

[0181] Fig. 5 illustrates a schematical representation of a hydrogen refueling station with a cooling system having a precooling stage, according to an embodiment of the invention.

[0182] The cooling system of the hydrogen refueling station 1 comprises a pre- cooling stage 15, but otherwise, the cooling system may be considered identical to the cooling systems described in relation to fig. 3 and fig 4. Therefore, the following description of the cooling system illustrated in fig. 5 will predominantly focus on the added precooling stage.

[0183] The precooling stage 15 comprises a precooling heat exchanger 16, and a precooling loop 14 thermally connecting the precooling heat exchanger 16 with the thermal energy storage by 20a. The precooling heat exchanger 16 thermally connects coolant flowing in the precooling loop 14 with hydrogen flowing into the precooling heat exchanger 16 via the flow path 4, during a refueling. The precooling loop 14 is similar to the other cooling loops and hence, is configured to circulate a flow ofcoolant. The coolant may be the same coolant as the coolant utilized in the other cooling loops. However, in principle a different coolant may also be utilized for the pre-cooling loop. The coolant circulating in the precooling loop 14 may transfer heat between the precooling heat exchanger 16 and the thermal energy storage 20a. Thus, the thermal energy storage 20a and the precooling heat exchanger 16 may be considered as being part of the precooling loop 14, and further may be considered as being thermally connected via the precooling loop 14. The precooling loop 14 comprises a valve V9, which may be controlled between a closed state and an open state. The valve V9 may be controlled between these states by the controller 43, e.g., based on sensor input, based on input informing the controller that a refueling is initiated, input informing that buildup of the thermal energy storage is initiated etc. E.g., the valve V9 may be controlled by the controller to a closed state during buildup of the thermal energy storage, as described, e.g., in relation to fig.4, and the valve may be controlled by the controller to an open state, when the precooling stage is used for cooling hydrogen.

[0184] The precooling heat exchanger 16 is located in the flow path 4 upstream the first heat exchanger 8, and thereby may be utilized to cool hydrogen before it enters the first heat exchanger 8 of the main cooling stage 21. Notice that the first heat exchanger 8 may sometimes be referred to as being part of a main cooling stage 21, and the cooling systems described in relation to fig. 1 to fig.4 may thus be considered a main cooling stage 21, when implemented in multistage cooling systems comprising either or both a precooling stage and a post-cooling stage. The precooling stage 15 utilizes the cooling capacity of the thermal energy storage to cool hydrogen via the precooling heat exchanger 16 during a refueling. When precooling is active, the valve V9 of the precooling loop is open. The precooling stage and the main cooling stage is typically both active during a refueling.

[0185] In a refueling example, a vehicle is connected to the dispenser 3 of the hydrogen refueling station 1. The refueling is initiated, and the hydrogen starts flowing from the hydrogen storage 2 to the vessel of the vehicle via the flow path 4 and the dispenser 3. As an example, the hydrogen entering the precooling heat exchanger 16has a temperature of 50 degrees Celsius. After being precooled by the precooling stage 15 via the precooling heat exchanger 16 based on cooling provided via the precooling loop 14 from the thermal energy storage 20a, the temperature of the hydrogen is reduced to 20 degrees Celsius as it enters the first heat exchanger 8 of the main cooling stage 21. After being cooled by the first heat exchanger, the temperature of the hydrogen is cascaded to minus 5 degrees Celsius. The example continues with a description of cooling with the first heat exchanger. During the refueling, the controller monitors the ambience temperature based on input from the ambience parameter sensor 22, which in this example is a temperature sensor. The ambience temperature measured with the sensor is 22 degrees in this example. This ambience temperature satisfies the first ambience condition since the measured ambience temperature is below the first ambience temperature threshold, which in this example is 39 degrees Celsius. As described elsewhere, e.g. in relation to figure 1 and fig. 3, this causes the controller to utilize the dry cooler 40 for cooling the hydrogen via the chiller 25, via the third cooling loop 9 and via the first cooling loop 6 and the first heat exchanger 8. Thus, the controller controls the valves V5 and V1 of the third 9 and the first cooling loop 6, respectively, to an open state, while closing the valves V4 of the fifth cooling loop 11 and valve V7 of the fourth cooling loop 10. Since the ambience temperature is relatively low, the thermal energy storage buildup condition is satisfied when the refueling is finished, and hence the buildup of the thermal energy storage is initiated. The buildup of the thermal energy storage is performed as described elsewhere in this disclosure, e.g., as described in relation to the description of fig. 4.

[0186] In another refueling example, the hydrogen has been cooled with the precooling stage 15 to a temperature of 25 degrees Celsius before the hydrogen enters the first heat exchanger. The ambience temperature measured with the ambience temperature sensor is high, above 39 degrees, causing the dry cooler 40 to be inefficient or not capable of providing sufficient cooling. In this example, the ambience temperature satisfies a second ambience condition, as described elsewhere in this disclosure, e.g., in relation to fig. 1 and fig.3, and thereby, the thermal energy storage 20a is utilized for cooling hydrogen in the main cooling stage 21 via the first heat exchanger 8 instead of the dry cooler 40. As the second ambience condition is satisfiedthe controller controls the valves V7 and V1 of the fourth 10 and first cooling loop 6, respectively, to an open state, while the valves V5 and V4 of the third 9 and fifth cooling loop 11, respectively, is controlled to a closed state. Thereby coolant is circulating in the fourth cooling loop and in the first cooling loop. Also, the precooling stage 15 is active, and hence, coolant is circulating in the precooling loop. Notice that in this example, the thermal energy storage 20a is used to cool both the precooling heat exchanger 16 of the precooling stage 15 and the first heat exchanger 8 of the main cooling stage 21. Since the ambience temperature is high in this example, the thermal energy storage buildup condition is not satisfied, and hence, the buildup of the thermal energy storage is not initiated even though the hydrogen refueling station is not currently refueling.

[0187] As previously mentioned, buildup of the thermal energy storage may be performed in the system comprising a pre-cooling stage 15 as described elsewhere in this disclosure, e.g., as described in relation to the description of fig. 4.

[0188] Optionally, the hydrogen refueling station may comprise a precooling bypass line configured to bypass the precooling heat exchanger. The bypass line is arranged to connect with the flow path upstream the precooling heat exchanger and connect with the flow path downstream the precooling heat exchanger, e.g., upstream the first heat exchanger.

[0189] Fig. 6 illustrates a schematical representation of a hydrogen refueling station with a cooling system having a post-cooling stage, according to an embodiment of the invention.

[0190] The cooling system of the hydrogen refueling station 1 comprises a post- cooling stage 45, but otherwise, the cooling system may be considered identical to the cooling systems described in relation to fig. 3 and fig 4. Therefore, the following description of the cooling system illustrated in fig. 6 will predominantly focus on the added post-cooling stage.

[0191] The post cooling stage 45 comprises a post-cooling heat exchanger 18, and a post-cooling loop 12 thermally connecting the post-cooling heat exchanger 18 with therefrigeration unit 13, which in turn is thermally connected to the chiller via a sixth cooling loop 42. The chiller 25 may thereby be utilized for cooling the refrigeration unit via the sixth cooling loop 42. The sixth cooling loop may optionally comprise a valve (not shown), which may be controlled by the controller 22. The post-cooling heat exchanger 18 thermally connects coolant flowing in the post-cooling loop 12 with hydrogen flowing into the post-cooling heat exchanger 18 via the flow path 4, during a refueling. The post-cooling loop 12 is similar to the other cooling loops and hence, is configured to circulate a flow of coolant. The coolant may be the same coolant as the coolant utilized in the other cooling loops, however it may also be a different coolant. E.g. the coolant may advantageously be carbon-dioxide refrigerant. The refrigerant, e.g., carbon dioxide may during operation have a temperature below, e.g., minus 50 degrees Celsius. The temperature may also be lower or higher. The coolant circulating in the post-cooling loop 12 may transfer heat between the post-cooling heat exchanger 18 and the refrigeration unit 13. Thus, the refrigeration unit 13 and the post- cooling heat exchanger 18 may be considered as being part of the post-cooling loop 12, and further may be considered as being thermally connected via the post-cooling loop 12. The post-cooling loop 12 comprises a valve V10, which may be controlled between a closed state and an open state. The valve V10 may be controlled between these states by the controller 43, e.g., based on sensor input, based on input informing the controller that a refueling is initiated or terminated, etc. E.g., the valve V10 may be controlled by the controller if during a refueling, hydrogen is already being sufficiently cooled by upstream cooling stages, including, e.g., the main cooling stage 21. One or more temperature sensors may be utilized to measure the temperature of the hydrogen, e. including measuring the temperature of hydrogen before it enters the post-cooling heat exchanger 18. The temperature measurements may be provided as input to the controller, and the controller may determine that the hydrogen has been sufficiently cooled. In this case, the valve V10 may be controlled to a closed state. Optionally, the hydrogen may also be lead through a post-cooling bypass line (not shown) that is arranged to enable hydrogen to bypass the post-cooling heat exchanger. The valve V10 may be controlled by the controller to an open state, when the precooling stage is used for cooling hydrogen.

[0192] The post-cooling heat exchanger 18 is located in the flow path 4 downstream the first heat exchanger 8, and thereby may be utilized to cool hydrogen before it enters the first heat exchanger 8 of the main cooling stage 21. In this example, the post- cooling stage 18 utilizes the carbon-dioxide refrigeration unit 13, which in turn is cooled by the chiller 25, to cool hydrogen via the post-cooling heat exchanger 18 during refueling. When post-cooling is active, the valve V10 of the post-cooling loop is open. The post-cooling stage 45 and the main cooling stage 21 is typically both active during a refueling.

[0193] During a refueling, hydrogen may typically first be cooled by the main cooling stage 21 to a temperature of, e.g., minus 5 degrees Celsius. The post-cooling stage may then cool the hydrogen further down to temperatures ranging between, e.g., 10 degrees Celsius to – 50 degrees Celsius. When refueling a high-capacity (heavy duty) vehicle such as, e.g., a truck, the temperature of hydrogen leaving the post- cooling heat exchanger 18 may be cooled to minus 30 degrees Celsius, while when refueling a normal car (light duty vehicle), the hydrogen may be cooled to minus 40 degrees Celsius, and when refueling, e.g., a bus, the hydrogen may be cooled to minus 20 degrees Celsius. The refueling station may also be utilized to fill trailers used to distribute hydrogen. When filling a trailer less cooling may be required, and in this use of the refueling station, hydrogen may only be cooled to minus 10 degrees Celsius or to minus 5 degrees Celsius or maybe the hydrogen is cooled even less that this. The mentioned temperatures of hydrogen being cooled by the cooling system may be achieved by providing less or more cooling by one stage and less or more cooling by another stage than what has been exemplified above. It should be understood that cooling hydrogen to a given temperature may in a multistage cooling system be achieved by cooling at the various stages of the cooling system. Thus, one stage, e.g., the main cooling stage may sometimes be controlled to provide more cooling than described above, or less cooling than described above, and similarly the post-cooling stage may provide less or more cooling than described above.

[0194] As illustrated, the refrigeration unit 13 is connected to the chiller 25 via the sixth cooling loop. Heat from refrigeration unit may thereby be transferred to thechiller 25 via coolant circulating in the sixth cooling loop 42. Because the chiller is used to cool the refrigeration unit via the sixth cooling loop, both the dry cooler and the thermal energy storage may be indirectly utilized to cool the refrigeration unit, depending on which of these two are connected to the chiller. The choice of whether to use the thermal energy storage or the dry cooler may depend on the ambience temperature, since the dry cooler do not cool efficiently at higher ambience temperatures, e.g., at ambience temperatures above, e.g., 40 degrees Celsius. The temperature of coolant circulating in the sixth cooling loop may during operation of the cooling system, e.g., be cooled to temperatures of minus 15 degrees Celsius to minus 10 degrees Celsius or to even lower or higher temperatures.

[0195] Fig.7 illustrates a hydrogen refueling station with a multistage cooling system having a precooling stage and a post-cooling stage, according to an embodiment of the invention.

[0196] The illustrated cooling system of the hydrogen refueling station 1 comprises a post-cooling stage 45 as illustrated in fig. 5, a precooling stage 15 as illustrated in fig. 6 and a main cooling stage, as described in relation to, e.g., the fig. 1, fig. 3, and fig.4. The control of the cooling system according to changing ambience parameter(s) (e.g., changing ambiance temperature) may be similar to the control described in relation to the other embodied cooling systems of the invention. E.g., whether the chiller 25 is cooled using the dry cooler 40 via the third cooling loop 9, or whether the chiller 25 is cooled using the thermal energy storage 20a via the fourth cooling loop 10 may be determined based on an ambience parameter and based on the first ambience condition and the second ambience. This control regime is described elsewhere, e.g. in relation to fig.1 and fig.3. Notice that the refrigeration unit 13 of the cooling system is also cooled by the chiller 25 via the sixth cooling loop 42, hence, whether the refrigeration unit 13 is cooled via the chiller 25 by the dry cooler 40 or by the thermal energy storage 20a is also determined based on the first and the second ambience condition and based on the ambience parameter. Further notice that the illustrated cooling system may be considered a cooling system similar to the cooling system illustrated in fig. 3 and fig. 4, only with an added precooling stage and an added postcooling stage. As such the buildup of the thermal energy storage may be controlled the same way as in these cooling systems.

[0197] The multistage cooling system comprising the precooling and the post- cooling stage in addition to the first heat exchanger is advantageous in that it has the effect of cooling hydrogen efficiently and fast from a storage temperature (which may be ambient temperature) to a first temperature level, a second temperature level and finally to a third temperature level, which is desired for gaseous hydrogen that is to be filled into a receiving vessel. The third temperature is the temperature of the hydrogen after it leaves the final cooling stage and may also sometimes be referred to as the refueling temperature. The refueling temperature may, e.g., be between minus 5 degrees Celsius to minus 50 degrees Celsius. The refueling temperature may depend on which type of vehicle that is refueled. E.g., when refueling a high-capacity (heavy duty) vehicle such as, e.g., a truck, the temperature of hydrogen leaving the post- cooling heat exchanger 18 may be cooled to minus 30 degrees Celsius, while when refueling a normal car (light duty vehicle), the hydrogen may be cooled to minus 40 degrees Celsius, and when refueling, e.g., a bus, the hydrogen may be cooled to minus 20 degrees Celsius.

[0198] Optionally, depending on which vehicle that is refueling and on the fueling protocol, the post-cooling stage may be bypassed if sufficient cooling is provided by the other cooling stages.

[0199] Optionally, further cooling stages may be introduced to the multistage cooling system.

[0200] Notice, that regarding the cooling stages and cooling loops, the circulation pump and / or compressor of a cooling loop may be turned off when the cooling loop and / or cooling stage is not in use, and thereby a reduction in power consumption of the cooling system may advantageously be achieved. The controller may control the activation / deactivation of circulation pumps and compressors. E.g., when circulation of coolant in a cooling loop is terminated by closing a valve of the cooling loop, the controller may at the same time deactivate a circulation pump and / or compressor ofthe cooling loop. The pump and / or compressor of a cooling loop may be activated by the controller when a valve of a cooling loop is opened by the controller to enable circulation in the cooling loop. Thereby, for each cooling loop, the activation / deactivation of circulation pumps and / or compressors of the cooling loop may be performed in concert with the opening / closing of valves of the cooling loop.

[0201] Notice that by having multiple cooling stages, the efficiency of the cooling system may advantageously improve.

[0202] Description without references to figures

[0203] In the following, embodiments of the invention, optional features of the invention and advantages of the invention is described without references to specific figures.

[0204] Optionally, the cooling systems and hydrogen refueling stations, including those illustrated in, e.g., fig. 1 and fig. 3 to fig. 7 may comprise a plurality of thermal energy storages. The energy storages may be serially connected or connected in parallel and / or the thermal energy storages may be used in different stages of multistage cooling systems. Providing additional thermal energy storages may increase the cooling capacity of the thermal energy storage.

[0205] A chiller, such as the chiller included in various embodiments of the invention may be known in the art as a closed loop refrigeration system using a coolant, e.g. a coolant such as a low GWP (GWP; Global Warming Potential) refrigerant e.g. <10 such as R717, R290, R600 or R1234Ze or the like and thus does not require any further explanation to be understood by a person skilled in the art. Notice that the chiller may also utilize other refrigerants than those mentioned above.

[0206] Multistage cooling system

[0207] A cascaded cooling system (sometimes referred to as multistage cooling system) with thermal energy storage 20a as described above is advantageous to use for cooling in a hydrogen refueling station, e.g., because calculations has shown that up to 9% of compressor energy may be reduced compared with a cooling system withouta thermal energy storage. Compared to cooling systems where the thermal energy storage itself is only used to cool the hydrogen directly, a reduction in compressor energy may also be proved.

[0208] It should be noted, that, if possible, the thermal energy storage may advantageously be recharged during nighttime where the utilization of hydrogen refueling stations are typically limited. In other words, there is a limited need for refueling during nighttime. Furthermore, recharge of the thermal energy storage during nighttime allows the cooling system, and in particular the dry cooler, to operate at higher efficiency as the ambient temperature is lower than during daytime. Also, the electricity prices level is low during night when recharging. Ther terms recharging, reestablishment, rebuild, buildup of the thermal energy storage may be used interchangeably to describe that the thermal energy storage is being cooled to build up the thermal energy storage.

[0209] It should be understood that the described and / or illustrated cooling systems may be implemented in a hydrogen refueling station, e.g., to cool hydrogen flowing from a hydrogen storage via one or more hydrogen pipes / flow paths into a tank / vessel of a vehicle being refueled using the hydrogen refueling station. As such, the cooling system(s) may be understood as hydrogen refueling station cooling system. Hence the cooling systems illustrated in, e.g., fig. 1 to fig. 7 may be considered hydrogen refueling station cooling systems.

[0210] It should be noted that the temperatures, circulation of coolant, conduction of hydrogen, etc. of all embodiments of this document may be controlled by one or more controllers. The control may be based on, e.g., predetermined threshold temperatures for hydrogen to be refueled to fuel cell vehicles, input from sensors such as temperature and pressure sensors including ambience temperature sensors, ambience conditions such as ambience temperature thresholds, expected demand for hydrogen to fuel cell vehicles, information from user interface of dispenser or the like. More specifically, the flow of coolant in the illustrated cooling loops (coolant flow paths / flow loops) may be controlled by two- or three-way valves.

[0211] The controller may, e.g., be a standard industrial controller comprising a data processor and a data storage (or associated data storage). The controller may in an embodiment be the same controller controlling the flow of hydrogen from the hydrogen storage to the dispenser and thereby to the receiving vessel of a vehicle. The hydrogen flow control may include control of a compressor, which may pressurize hydrogen gas from a storage including from a temporary storage such as from a trailer. The controller may prepare the cooling system for future cooling of hydrogen to comply with temperature requirements to hydrogen of various fueling protocols.

[0212] From the above, it is understood, that generally the first heat exchanger can be used for cooling of hydrogen. One example is as mentioned above for cooling hydrogen during refueling of a fuel cell vehicle. Another example is cooling of hydrogen delivered to a hydrogen refueling station in a temporary hydrogen storage such as a trailer. It is advantageous to cool such hydrogen prior to storing it in a hydrogen storage and such cooling may be performed by a cooling system as described in the present document. This is because typically hydrogen is pressurized by a compressor and thereby heated up both at the compressor but also as it is being stored in the hydrogen storage at an increased pressure. Such pressure may be, e.g., up to 100Mpa.

[0213] The use of a thermal energy storage 20a as illustrated in a one, two and three stage cooling system such as the systems illustrated in fig. 1 to fig. 7 is advantageous in that dry cooler, the precooling stage, the thermal energy storage and the post-cooling stage comprising the refrigeration unit may operate at different temperature levels, e.g., the dry cooler may operate at lower temperature than thermal energy storage. The thermal energy storage may be used for pre-cooling and / or for cooling via the chiller, (including the first heat exchanger) and reduce the load on the other cooling stages that may be able to efficiently cool the hydrogen to even lower temperatures. This may advantageously reduce the load on the other cooling stages. E.g., the three-stage temperature cascading with thermal energy storage, dry cooler, chiller and refrigeration unit, as illustrated in fig. 7, offers lower load on the cooling system with lower power consumption as an outcome.

[0214] Optionally, the control of the illustrated cooling system may be combined with a control strategy that is accommodated to operate with smart grid, i.e. the thermal energy storage may be regenerated when energy prices / demand is low, and / or when ambient conditions are favorable, e.g., when the temperature is low. Accordingly, the thermal energy storage may optionally be recovered at favorable conditions by taking into account weather conditions (ambient temperature), energy price, required cooling capacity demand, forecast, etc. Hence, the cooling systems of the invention may be controlled by a controller controlling circulation of the coolant in the cooling loops, based on input related to ambient temperature, and optionally based on energy price, energy availability, state of charge of the thermal energy storage, temperature measurement of the hydrogen to be cooled, etc.

[0215] The cooling of hydrogen may be dependent on ambient temperature as described in relation to various embodiments of the invention. Advantageously, when the ambient temperature is low, the chiller operates more efficiently as it does not have to operate at high temperature difference between a condensing and evaporating temperature, in turn improving, i.e., the coefficient of performance (efficiency).List of refences 1. Hydrogen refueling station 2. Hydrogen storage 3. Dispenser 4. Flow path 5. Receiving vessel 6. First cooling loop 7. Second cooling loop 8 First heat exchanger 9. Third cooling loop 10. Fourth cooling loop 11. Fifth cooling loop 12. Post-cooling loop 13. Refrigeration unit 14. Precooling loop 15. Precooling stage 16. Precooling heat exchanger 17. Coolant pump 18. Post-cooling heat exchanger 19ca. First coolant flow loop line 19cb. Second coolant flow loop line 19cc. Third coolant flow loop line 20a. Thermal energy storage 21. Main cooling stage 22 Controller 25 Chiller 38. Cooling system 39a. First supplementary heat exchanger 39b. Second supplementary heat exchanger 40. Dry cooler 41. Cooling loop compressor 42. Sixth cooling loop43. Ambience parameter sensor 44. Communication line 45. Post-cooling stage V1-V10 Valves

Claims

Patent claims 1. A hydrogen refueling station (1) comprising: a hydrogen storage (2) fluidly connected to a hydrogen dispenser (3) via a flow path (4), a cooling system (38) comprising: a first cooling loop (6) configured to conduct a coolant flow, wherein said first cooling loop (6) comprises a first heat exchanger (8) thermally connected to at least a part of said flow path (4a); a chiller (25) thermally connected to said first heat exchanger (8) via said first cooling loop (6); a dry cooler (40) thermally connectable to said chiller (25) via a third cooling loop (9) configured to conduct a coolant flow, wherein said third cooling loop (9) comprises a valve (V5); a thermal energy storage (20a) thermally connectable to said chiller (25) via a fourth cooling loop (10) configured to conduct a coolant flow, wherein said fourth cooling loop (10) comprises a valve (V7); a controller (22) configured to control said valve (V5) of said third cooling loop (9) to an open state to establish a coolant flow in said third cooling loop (9) when said one or more ambience parameter(s) satisfies a first ambience condition, and thereby thermally connecting said dry cooler (40) to said chiller (25) via said third cooling loop (9); and wherein said controller is further configured to control said valve (V7) of said fourth cooling loop (10) to an open state to establish a coolant flow in said fourth cooling loop (10) when said one or more ambience parameter(s) satisfies a second ambience condition, and thereby thermally connecting said thermal energy storage (20a) to said chiller (25) via said fourth cooling loop (10).

2. A hydrogen refueling station (1) according to claim 1, wherein said one or more ambience parameter(s) includes a temperature and wherein said first ambience condition includes temperatures below a temperature threshold.

3. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said temperature threshold is below 50 degrees Celsius, such as below 45 degrees Celsius, such as equal to or below 40 degrees Celsius.

4. A hydrogen refueling station (1) according to any one of the preceding claims wherein said temperature is an ambience temperature and / or a coolant temperature of a coolant in said third cooling loop.

5. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said one or more ambience parameter(s) include an ambience temperature, and wherein said first ambience condition includes ambience temperatures below a first ambience temperature threshold.

6. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said one or more ambience parameter(s) include a coolant temperature, and wherein said first ambience condition includes coolant temperatures below a first coolant temperature threshold.

7. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said one or more ambience parameter(s) include an ambience temperature, and wherein said second ambience condition includes ambience temperatures equal to or above a second ambience temperature threshold.

8. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said one or more ambience parameter(s) include a coolant temperature, and wherein said second ambience condition includes coolant temperatures equal to or above a second ambience temperature threshold.

9. A hydrogen refueling station (1) according to any one of the preceding claims wherein said coolant temperature is a temperature of coolant in said third cooling loop.

10. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said second ambience temperature threshold is lower than said first ambience temperature threshold.

11. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said hydrogen refueling station (1) comprises one or more ambience parameter sensor(s) configured to measure said one or more ambience parameter(s).

12. A hydrogen refueling station (1)b according to any one of the preceding claims, wherein said one or more ambience parameter sensor(s) includes a temperature sensor arranged to measure said ambience temperature.

13. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said one or more ambience parameter sensor(s) includes a temperature sensor arranged to measure a temperature of coolant.

14. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said temperature sensor arranged to measure a temperature of coolant is arranged to measure a temperature of coolant in said third cooling loop.

15. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said controller controls said valve (V5) of said third cooling loop (9) to a closed state when said one or more ambience parameter(s) does not satisfy said first ambience condition.

16. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said controller controls said valve (V7) of said fourth cooling loop (10) to a closed state when said one or more ambience parameter(s) does not satisfy said second ambience condition.

17. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said chiller is thermally connectable to said thermal energy storage (20a) via a fifth cooling loop (11) configured to circulate a coolant flow of cooled down coolant from the chiller to the thermal energy storage, and wherein said fifth cooling loop comprises a fourth valve (V4).

18. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said controller is configured to establish a buildup of said thermal energy storage (20a) by controlling said fourth valve (V4) of said fifth cooling loop (11) to an open state to establish a coolant flow of cooled down coolant from said chiller to said thermal energy storage (20a) via said fifth cooling loop.

19. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said first cooling loop (6) comprises a first valve V1, and wherein said controller is configured to establish a buildup of said thermal energy storage (20a) by controlling said fourth valve (V4) of said fifth cooling loop (11) to an open state and further controlling said first valve (V1) of said first cooling loop to a closed state to establish a coolant flow of cooled down coolant from said chiller to said thermal energy storage (20a) via said fifth cooling loop, while terminating a coolant flow in said first cooling loop.

20. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said controller is configured to establish a buildup of said thermal energy storage (20a) by controlling said fourth valve (V4) of said fifth cooling loop (11) to an open state, and further by controlling said valve (V5) of said third cooling loop to an open state, and further controlling said first valve (V1) of said first cooling loop to a closed state to establish a coolant flow in said third cooling loop (9), and to establish a coolant flow of cooled down coolant from said chiller to said thermal energy storage (20a) via said fifth cooling loop, and to terminate a coolant flow in said first cooling loop.

21. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said controller is configured to establish said buildup of said thermal energy storage (20a) only when said hydrogen refueling station (1) is not performing a refueling via said flow path (4).

22. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said controller is configured to establish a buildup of said thermal energystorage (20a) when at least one ambience parameter of said one or more ambience parameter(s) satisfies a thermal energy storage buildup condition.

23. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said at least one ambience parameter of said one or more ambience parameter(s) is an ambience temperature and wherein said thermal energy storage buildup condition includes ambience temperatures below a third ambience temperature threshold.

24. A hydrogen refueling station (1) according to any one of the preceding, claims wherein said first ambience temperature threshold is withing the range of 25 degrees Celsius to 45 degrees Celsius, such as within the range of 30 degrees Celsius to 45 degrees Celsius, such as within the range of 35 degrees Celsius to 42 degrees Celsius, such as withing the range of 38 degrees Celsius to 40 degrees Celsius, such as preferably 40 degrees Celsius.

25. A hydrogen refueling station (1) according to any one of the preceding, claims wherein said second ambience temperature threshold is withing the range of 25 degrees Celsius to 45 degrees Celsius, such as within the range of 30 degrees Celsius to 45 degrees Celsius, such as within the range of 35 degrees Celsius to 42 degrees Celsius, such as withing the range of 38 degrees Celsius to 40 degrees Celsius, such as preferably 40 degrees Celsius.

26. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said third ambience temperature threshold is equal to said first ambience temperature threshold.

27. A hydrogen refueling station (1) according to any of the claims 23 or 26, wherein said third ambience temperature threshold is equal to or below 48 degrees Celsius, such as equal to or below 44 degrees Celsius, such as equal to or below 42 degrees Celsius, such as equal to or below 40 degrees Celsius, such as equal to or below 38 degrees Celsius, such as equal to or below 35 degrees Celsius, such as equal to or below 32 degrees Celsius, such as equal to or below 29 degrees Celsius.

28. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said chiller (25) comprises a second cooling loop (7), said second cooling loop (7) comprising a first supplementary heat exchanger (39a) and a second supplementary heat exchanger (39b), and wherein said first supplementary heat exchanger (39a) is fluidly connected to said second supplementary heat exchanger (39b), and wherein said chiller is thermally connected to said first cooling loop via said first supplementary heat exchanger (39a).

29. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said second supplementary heat exchanger (39b) is thermally connectable to said dry cooler via a third cooling loop (9).

30. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said second supplementary heat exchanger (39b) is thermally connectable to said thermal energy storage (20a) via a fourth cooling loop (10).

31. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said first supplementary heat exchanger (39a) is thermally connectable to said thermal energy storage (20a) via a fifth cooling loop (11) comprising a valve (V4).

32. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said controller is configured to close said fourth valve (V4) of said fifth cooling loop (11) when said one or more ambience parameter(s) does not satisfy said thermal energy storage buildup condition or when said hydrogen refueling station is performing a refueling via said flow path (4).

33. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said thermal energy storage (20a) comprises a tank including a phase change material.

34. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said phase change material has a melting point within a temperature range of minus 20 degrees Celsius to 40 degrees Celsius, such as withing the range of minus 15degrees Celsius to thirty degrees Celsius, preferably minus 5 degrees Celsius to 5 degrees Celsius, such as substantially 0 degrees Celsius.

35. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said phase change material is water.

36. A hydrogen refueling station (1) according to any one of the preceding claims, wherein a cooling capacity of said thermal energy storage is at least 300 kWh, such as within the range of 300kWh to 1300kWh, such as withing the range of 400kWh to 1000 kWh, such as within the range of 500kWh to 700kWh.

37. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said cooling system (38) comprises a precooling stage (15) comprising: a precooling heat exchanger (16) thermally connected to a second part of said flow path (4); a precooling loop (14) configured to conduct a coolant flow, and wherein said thermal energy storage (20a) is thermally connectable to said precooling heat exchanger (16) via said precooling loop (14).

38. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said second part of said flow path (4) is located upstream said first heat exchanger (8).

39. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said cooling system (38) comprises a post-cooling stage (19) comprising a post-cooling loop (12) configured to conduct a coolant flow, wherein said post-cooling loop (12) comprises a refrigerant unit (13) and a post-cooling heat exchanger (18) thermally connected to a third part of said flow path (4) and wherein said post-cooling heat exchanger (18) and said refrigerant unit (13) is thermally connectable via said post-cooling loop (12).

40. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said refrigeration unit is thermally connected to said chiller (25) via a sixth cooling loop to enable cooling of refrigerant circulating in said refrigeration unit by the chiller.

41. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said refrigeration unit is using carbon dioxide as a refrigerant.

42. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said third part of said first flow path (4) is located downstream said first heat exchanger (8).

43. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said cooling system is configured for cooling an average hydrogen flow through said flow path of at least 6.5kg / min.

44. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said coolant is an antifreeze liquid.

45. A hydrogen refueling station (1) according to any one of the preceding claims, wherein said coolant include ethylene glycol-based coolant or a propylene glycol- based coolant.

46. A method of cooling a hydrogen flow, said method comprising: establishing a hydrogen flow from a hydrogen storage (2) to a hydrogen dispenser (3) via a flow path (4), establishing a coolant flow in a first cooling loop (6) comprising a chiller and a first heat exchanger (8) thermally connected to at least a part of said flow path (4a); obtain one or more ambience parameter(s); determine that said one or more ambience parameter(s) satisfies a first ambience condition and / or a second ambience condition;wherein when said one or more ambience parameter(s) satisfies said first ambience condition establishing a coolant flow in a third cooling loop, said third cooling loop thermally connecting a dry cooler (40) with said chiller (25); and wherein when said one or more ambience parameter(s) satisfies said second ambience condition establishing a coolant flow in a fourth cooling loop (10), said fourth cooling loop (10) thermally connecting a thermal energy storage (20a) to said chiller (25).

47. A method according to claim 46, wherein said one or more ambience parameter(s) includes a temperature and wherein said first ambience condition includes temperatures below a temperature threshold.

48. A method according to any one of the claims 46-47, wherein said one or more ambience parameter(s) includes a temperature and wherein said second ambience condition includes temperatures below a temperature threshold.

49. A method according to any one of the claims 46-48, wherein said method is configured to be performed by said hydrogen refueling station according to any one of the claims 1-45.

50. A hydrogen refueling system comprising a hydrogen refueling station (1) according to any of the claims 1-45, and further comprising a vehicle connected to said dispenser of said hydrogen refueling station (1).

51. Use of a hydrogen refueling station (1) to perform said method according to claim 46-49.

52. A cooling system (38) for a hydrogen refueling station; the cooling system comprising: a first cooling loop (6) configured to conduct a coolant flow, wherein said first cooling loop (6) comprises a first heat exchanger (8) thermally connectable to at least a part of a flow path (4a) configured to conduct a hydrogen flow;a chiller (25) thermally connected to said first heat exchanger (8) via said first cooling loop (6); a dry cooler (40) thermally connectable to said chiller (25) via a third cooling loop (9) configured to conduct a coolant flow, wherein said third cooling loop (9) comprises a valve (V5); a thermal energy storage (20a) thermally connectable to said chiller (25) via a fourth cooling loop (10) configured to conduct a coolant flow, wherein said fourth cooling loop (10) comprises a valve (V7); one or more ambience parameter sensor(s) configured to measure one or more ambience parameter(s); a controller (22) configured to control said valve (V5) of said third cooling loop (9) to an open state to establish a coolant flow in said third cooling loop (9) when one or more ambience parameter(s) satisfies a first ambience condition, and thereby thermally connecting said dry cooler (40) to said chiller (25) via said third cooling loop (9); and wherein said controller is further configured to control said valve (V7) of said fourth cooling loop (10) to an open state to establish a coolant flow in said fourth cooling loop (10) when said one or more ambience parameter(s) satisfies a second ambience condition, and thereby thermally connecting said thermal energy storage (20a) to said chiller (25) via said fourth cooling loop (10).

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