Direct air capture system and method of providing a direct air capture system

Abstract

Various embodiments concern a direct air capture system comprising: a plurality of direct air capture units configured to take in ambient air; the plurality of direct air capture units comprising a first direct air capture unit and a second direct air capture unit; a fluid connection between the first direct air capture unit and the second direct air capture unit to facilitate thermal transfer therebetween, the fluid connection comprising a heat transfer fluid; at least one plurality of branch controllers, wherein each the at least one branch controller of the plurality of branch controllers is configured to control each direct air capture unit of the plurality of direct air capture units; and wherein the at least one branch controller is configured to operate the first direct air capture unit and the second direct air capture unit in a desorption mode and an adsorption mode respectively, such that heat energy absorbed by the first direct air capture unit result in a cooled heat transfer fluid which is used to absorb heat energy from the second direct air capture unit.

Description

DIRECT AIR CAPTURE SYSTEM AND METHOD OF PROVIDING A DIRECT AIR CAPTURE SYSTEMTechnical field

[0001] Various aspects of this disclosure relate to a direct air capture (DAC) system and a method of providing a direct air capture system.Background

[0002] The following discussion of the background art is intended to facilitate an understanding of the present disclosure only. It should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was published, known or is part of the common general knowledge of the person skilled in the art in any jurisdiction as of the priority date of the disclosure.

[0003] Conventional direct air capture (DAC) technology focuses primarily on capturing carbon dioxide (CO2) directly from the atmosphere efficiently and economically. For a DAC system, the desorption process is highly energy -intensive. It involves breaking the chemical bonds between the sorbent material and the captured CO2, which requires a significant amount of consistent heating energy. This heating is necessary to raise the temperature of the sorbent to the point where the CO2 can be released. After the desorption process, the system can then be cooled, which adds another layer of energy consumption and further reduces overall energy efficiency.

[0004] There exists a need to mitigate the energy inefficiencies.Summary

[0005] The present disclosure seeks to provide a technical solution in the form of a DAC system by leveraging the cooling energy generated by a modular DAC unit (also referred to as a DAC module) as a by-product of the required heating energy through an air conditioning cycle system. Whenever there is a demand for heating, the resultant cooling effect is captured and utilized to pre-cool the incoming air or cool other parts of the system that are in adsorption mode. This not only reduces the total energy consumption but also enhances the operational efficiency of the DAC system, ensuring that the sorbent materials operate under optimal temperature conditions. By effectively utilizing both heating and cooling energies, the system achieves a more balanced and energy-efficient performance.

[0006] Various embodiments concern a direct air capture system comprising: a plurality of direct air capture units configured to take in ambient air; the plurality of direct air capture units comprising a first direct air capture unit and a second direct air capture unit; a fluid connection between the first direct air capture unit and the second direct air capture unit to facilitate thermal transfer therebetween, the fluid connection allowing a heat transfer fluid to flow therethrough; at least one branch controller, wherein the at least one branch controller is configured to control each direct air capture unit of the plurality of direct air capture units; and wherein the at least one branch controller is configured to operate the first direct air capture unit and the second direct air capture unit in a desorption mode and an adsorption mode at the same time, such that heat energy absorbed by the first direct air capture unit result in a cooled heat transfer fluid which is used to absorb heat energy from the second direct air capture unit.

[0007] Various embodiments concern a method of providing a direct air capture system, comprising: configuring a plurality of direct air capture units to take in ambient air; the plurality of direct air capture units comprising a first direct air capture unit and a second direct air capture unit; providing a fluid connection between the first direct air capture unit and the second directair capture unit to facilitate thermal transfer therebetween, the fluid connection allowing a heat transfer fluid to flow therethrough; and configuring at least one branch controller to control each direct air capture unit of the plurality of direct air capture units; wherein the at least one branch controller is configured to operate the first direct air capture unit and the second direct air capture unit in a desorption mode and an adsorption mode, or vice-versa, at the same time.

[0008] The dependent claims define some examples associated with the direct air capture system and method of providing the direct air capture system, respectively.Brief description of the drawings

[0009] The disclosure will be better understood with reference to the detailed description when considered in conjunction with the non-limiting examples and the accompanying drawings, in which:- FIG. 1 shows a schematic diagram of a modular direct air capture (DAC) unit and the integration with an air-handling unit (AHU) according to various embodiments;- FIG. 2 shows a schematic diagram of a direct air capture (DAC) system according to various embodiments;- FIG. 3 shows a schematic diagram of a modular DAC unit according to various embodiments;- FIG. 4 shows a diagram of various parts of a control signal for controlling or operating the DAC system according to various embodiments.Detailed description

[0010] The following detailed description refers to the accompanying drawings that show, by way of illustration, specific details and embodiments in which the disclosure may bepracticed. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure. Other embodiments may be utilized and structural, and logical changes may be made without departing from the scope of the disclosure. The various embodiments are not necessarily mutually exclusive, as some embodiments can be combined with one or more other embodiments to form new embodiments.

[0011] Features that are described in the context of an embodiment may correspondingly be applicable to the same or similar features in the other embodiments. Features that are described in the context of an embodiment may correspondingly be applicable to the other embodiments, even if not explicitly described in these other embodiments. Furthermore, additions and / or combinations and / or alternatives as described for a feature in the context of an embodiment may correspondingly be applicable to the same or similar feature in the other embodiments.

[0012] In the context of various embodiments, the articles “a”, “an” and “the” as used with regard to a feature or element include a reference to one or more of the features or elements.

[0013] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0014] As used herein, the terms “first”, “second”, “third”, “fourth”, and so on, are used for purposes of clarity and do not imply order or precedence.

[0015] As used herein, the term “data” may be understood to include information in any suitable analog or digital form, for example, provided as a file, a portion of a file, a set of files, a signal or stream, a portion of a signal or stream, a set of signals or streams, and the like. The term data, however, is not limited to the aforementioned examples and may take various forms and represent any information as understood in the art.

[0016] As used herein, the term “processor” refers to a circuit, including analog circuits, digital circuits, or hybrid circuits, or their constituent components. Any other kind of implementation of the respective functions which will be described in more detail below mayalso be understood as a “circuit” in accordance with an alternative embodiment. A digital circuit may be understood as any kind of a logic implementing entity, which may be special purpose circuitry or a processor executing software stored in a memory, or a firmware.

[0017] As used herein, the term “sorption” broadly refers to any physical or chemical process in which a substance or compound is sorbed (adsorbed or absorbed) on or in another substance. The term “desorption” may be construed as the release of an adsorbed substance from a surface.

[0018] Various embodiments generally relate to a direct air capture (DAC) system. In particular, various embodiments generally relate to a DAC system employing the use of DAC technology to harness the advantage thereof so as to indirectly reduce carbon footprint of an air management system. The indirect carbon footprint reduction may be achieved through energy savings, with a focus on saving latent cooling load of inlet air with the application of DAC.

[0019] According to various embodiments, the DAC system may be synergistically combine with a heating, ventilation and / or air conditioning (HVAC) system to form the air management system. Accordingly, various embodiments may provide that the operation of DAC, e.g. the adsorption and the regeneration processes, occur continuously and synchronously in the air management system so as to ensure uninterrupted operation of the HVAC system for providing a comfortable indoor environment for occupants. According to various embodiments, the DAC system may capture water, in the form of moisture (H2O) and carbon dioxide (CO2), via adsorption, from ambient air being drawn into (or supplied to) the HVAC system. The adsorption of the moisture may reduce the latent cooling load of the HVAC system. Further, the adsorption of the CO2 may reduce an indoor CO2 level, which may in turn increase the utilization of return air by the HVAC system resulting in a higher return air ratio. The higher return air ratio may reduce the amount of fresh ambient air being drawn and cooledby the HVAC. The reduction in latent cooling load and the reduction in the amount of fresh ambient air to be cooled may lead to energy savings which may contribute to indirect carbon footprint reduction. According to various embodiments, the DAC system may also be configured to regenerate and release the captured CO2 back into the atmosphere in order to provide a continuous operation of DAC without expensing energy for CO2 storage or utilization. Therefore, the various embodiments are capable of achieving indirect carbon footprint reduction through energy savings and provide a sustainable and resource-efficient approach to air treatment by adsorption of moisture and CO2 and by regeneration thereof.

[0020] FIG. 1 shows a schematic diagram of a modular DAC unit and the integration with an AHU according to various embodiments.

[0021] Various embodiments concern a direct air capture system comprising: a plurality of direct air capture units configured to take in ambient air; the plurality of direct air capture units comprising a first direct air capture unit and a second direct air capture unit; a fluid connection between the first direct air capture unit and the second direct air capture unit to facilitate thermal transfer therebetween, the fluid connection comprising a heat transfer fluid; at least one branch controller, wherein the at least one branch controller is configured to control each direct air capture unit of the plurality of direct air capture units; and wherein the at least one branch controller is configured to operate the first direct air capture unit and the second direct air capture unit in a desorption mode and an adsorption mode respectively.

[0022] In operation, heat energy absorbed by the first direct air capture unit result in a cooled heat transfer fluid which is used to absorb heat energy from the second direct air capture unit.

[0023] It is appreciable that the terms “first” and “second” in the direct air capture units are not limiting and are used for example. Therefore, it can be appreciated that the second direct air capture unit may be operating in the desorption mode and the first air capture unit operatingin the adsorption mode, such that the heart energy absorbed by the second direct air capture unit may allow the cooled heat transfer fluid to cool down the first direct air capture unit.

[0024] In various embodiments, there may comprise a plurality of branch controllers, and each branch controller may be associated with controlling one direct air capture unit.

[0025] In various embodiments, the direct air capture system may include a processor, the processor configured to determine whether one or more direct air capture units of the plurality of direct air capture units will be operating in the desorption mode and / or the adsorption mode based on a logic comprising direct air capture properties, wherein the processor may be configured to send control signals to each branch controller to set each direct air capture unit to either a desorption mode or a adsorption mode.

[0026] In various embodiments, each direct air capture unit of the plurality of direct air capture units have a cooling coil for adsorption and a heating coil for desorption.

[0027] In various embodiments, the DAC properties comprises one of more of the following: amount of moisture of ambient air, adsorption capacity, threshold of sorbent saturation and completeness of desorption.

[0028] In various embodiments, there are three times more direct air capture units operating in the adsorption mode (also may be referred to as cooling mode), than in the desorption mode (also may be referred to as a heating mode).

[0029] In various embodiments, each control signal sent by the processor may comprise three data parts, wherein the first data part indicates the priority, the second data part indicates whether to start or stop and the third data part indicates whether the direct air capture unit should be in heating or cooling mode.

[0030] In various embodiments, the control signals sent by the processor are based on one of the following: detection of a sorbent breakthrough state, end of adsorption state, end of desorption state, end of air cooling, cooled adsorption and uncooled adsorption.

[0031] In various embodiments, the plurality of direct air capture units are configured for connection to an air ventilation or air-conditioning system, the air ventilation system may comprise a compressor and an outdoor unit. In various embodiments, there may comprise a air ventilation or air-conditioning system comprising the plurality of direct air capture units.

[0032] In various embodiments, plurality of direct air capture units are used to cool down a data center.

[0033] FIG. 1 illustrates a plurality of modular DAC units 102A, 102B, 102C and how the modular DAC units may be stackable together to be integrated into a DAC system. Heating and cooling coils (shown in FIG. 2) are placed inside or within each of these modular DAC unit for cooling and desorption purpose.

[0034] As shown in FIG. 1, the plurality of air capture units 102 includes direct air capture units 102A, 102B and 102C. The entire system may operates like a mini -variable refrigerant flow (mini-VRF) system, where each modular DAC unit may comprise its own controls for heating and cooling. Each DAC unit 102 A, 102B, 102C, may be arranged in fluid connection or fluid communication with an adjacent DAC unit, and / or with one or more DAC units within the same stack. The DAC system may utilize the cooling energy generated from the heating requirement for the desorption process associated with at least one modular DAC unit to cool other modular DAC units in adsorption mode. Such an arrangement or configuration enables the leveraging of cooling energy generated as a by-product of the required heating energy through the air conditioning cycle system. It may be appreciable that the fluid connection may be a pipe or conduit. Fluid flowing within the fluid connection may be a heat transfer fluid, such as a refrigerant.

[0035] Each direct air capture unit 102A, 102B and 102C may be able to take in ambient air and cool or heat the ambient air and release the air through an air-handling unit (AHU), for example, via an air inlet of the AHU.

[0036] Each modular DAC unit 102 A, 102B and 102C has its own controls for enabling the operation of the DAC unit in a heating mode and a cooling mode. The heating mode may be configured for sorbent desorption after the material is saturated with H2O and CO2. The cooling mode may serve two purposes: first, it pre-cools the incoming air; second, for prolonged operation, because at lower temperatures, the sorbent has higher H2O and CO2 adsorption capacities, which is desirable for the prolonged operation. In some embodiments, the heating mode is associated with the desorption process, and a cooling mode is associated with the adsorption process.

[0037] FIG. 2 shows a schematic diagram of a direct air capture system 200 according to various embodiments.

[0038] As shown in FIG. 2, there comprises a plurality of air capture units 202, which includes direct air capture units 202A, 202B, 202C and 202D. The entire system operates like a mini-VRF system, where each modular DAC unit has its own controls for heating and cooling, and wherein the mini-VRF system uses refrigerant for both air conditioning and heating.

[0039] Each direct air capture units 202 A, 202B, 202C and 202D are able to take in ambient air and cool or heat the ambient air.

[0040] Each modular DAC unit 202 A, 202B and 202C has its own controls for toggling between a heating mode and a cooling mode. The heating and cooling modes may be enabled by providing heat energy to conductor coils 210A, 210B, 210C to achieve the heating mode, and removal of heat energy to the conductor coils 210A, 210B, 210C to achieve the cooling mode. The heating may be for sorbent desorption after the material is saturated with H2O and CO2. Cooling serves two purposes: first, it pre-cools the incoming air; second, at lower temperatures, the sorbent has higher H2O and CO2 adsorption capacities, which is desirable for prolonged operation.

[0041] As shown there are a plurality of branch controllers 204, wherein each branch controller for example 204A, 204B, 204C of the plurality of branch controllers is configured to control each direct air capture unit 202A, 202B and 202C of the plurality of direct air capture units. There may further comprise a processor which is configured to determine which DAC unit of the plurality of direct air capture units should be in cooling or heating mode based on DAC properties.

[0042] In various embodiments, the entire system operates like a mini-VRF system, where each modular DAC unit has its own controls for heating and cooling. A branch controller manages the switching between heating and cooling processes as needed.

[0043] In various embodiments, in the integration of modular DAC units and air-handling units (AHUs), such as HVAC systems , to ensure continuous operation and consistent fresh air delivery to indoor space, the modular DAC units operates in different modes at the same time (adsorption and desorption).

[0044] In various embodiments, the direct air capture unit 202A, 202B and 202C are connected to the respective plurality of branch controllers 204 A, 204B, 204C, which are in turn connected to a compressor 206 and an outdoor unit 208.

[0045] When the first direct air capture unit, for example 202A is operating in a desorption mode, heat energy from the heat transfer fluid is absorbed by the first direct air capture unit 202A, resulting in a cooled heat transfer fluid. The cooled heat transfer fluid may then be used to absorb heat from the second direct air capture unit 202B, which configured to operate in an adsorption mode, and wherein the second direct air capture unit is cooled by thermal connection between the first direct air capture unit 202 A and second direct air capture unit 202B. In some embodiments, there may comprise a plurality of second direct air capture units 202B, 202C, and 202D, operating in the adsorption mode. Various permutations of the direct air capture units 202 operating in different modes may be contemplated.

[0046] In various embodiments, considering the desorption time is normally a third of the adsorption time, every four modular DAC units, there are around 3 units in adsorption mode and 1 unit in desorption mode. This utilizes the cooling energy generated from the heating requirement for the desorption process to cool other modular units in adsorption mode. This approach saves energy by pre-cooling the incoming ambient air and ensures better performance of the sorbents. When there is a heating demand for desorption, the coils function or act as a condenser to discharge heat. Correspondingly, evaporation occurs for heat removal, which is utilized to cool other DAC units that are still in adsorption mode.

[0047] Since there are approximately three times as many modular DAC units in adsorption mode as in desorption mode, more coils are in cooling mode. When the main condenser is not in use, there is no heat being discharged into the atmosphere. With at least two modular units being cooled and one not cooled, the energy is utilized to maximum extent because both cooling & heating are required.

[0048] FIG. 3 shows a schematic diagram of modular DAC unit 302 according to various embodiments, illustrating an operation configuration of the modular DAC unit 302.

[0049] In various embodiments, the DAC unit 302 is connected to a branch controller 304 for controlling the DAC unit 302. As shown in FIG. 3, there are two positions a and b. Position a is located before the ambient air enters the DAC unit 302 and position b is location after the ambient air enters the modular DAC unit 302.

[0050] In various embodiments, there may be at least one sensor located in each of position a and b to monitor or measure properties of the ambient air at each position, also referred to as DAC properties.

[0051] In various embodiments, the properties may be one of the following: an amount of moisture of ambient air, an adsorption capacity, a threshold of sorbent saturation and a completeness level of desorption.

[0052] In various embodiments, the at least one sensor may be configured to monitor or collect such data and send it to the processor for further processing. The processor then uses these data to decide whether each modular DAC unit should be in heating or cooling mode.

[0053] In various embodiments, to further save energy, not all modular DAC units require cooling. Therefore, there may comprise a logic, implementing an algorithm, to determine which units should be cooled, and when to switch between cooling and heating, is used. The algorithm may be implemented as software codes stored in a non-transitory computer-readable medium in a processor.

[0054] The processor uses the algorithm as well as the data from the sensors to determine which units should be cooled, and when to switch between cooling and heating, is used.

[0055] Table 1 shows an example of the control algorithm criteria, action and control signal(s) sent during each operation or process. The criteria may be implemented as conditions or constraints.<>>

[0056] In various embodiments, the criteria for the switching from cool or heat mode under different processes are based on the algorithm. “Cb-H2O” refers to the amount of moisture at point b. “CH2O-0” refers to the adsorption capacity of the sorbent for moisture, “a” refers tothe threshold set for sorbent saturation during adsorption. “r|” refers to the coefficient to determine the completeness of the desorption process.

[0057] In various embodiments, the control signals are based on one of sorbent breakthrough, end of adsorption, end of desorption, end of air cooling, cooled adsorption and uncooled adsorption.

[0058] In various embodiments, this control signals are sent by the processor to the branch controllers.

[0059] FIG. 4 shows a diagram of various parts of a control signal according to various embodiments.

[0060] The control signal may be used for paring control of the processes.

[0061] In various embodiments, the control signals comprise of three data parts, wherein the first data part indicates the priority, the second data part indicates whether to start or stop and the third data part indicates whether the direct air capture unit should be in heating or cooling mode.

[0062] In various embodiments, the control signals are based on one of sorbent breakthrough, end of adsorption, end of desorption, end of air cooling, cooled adsorption and uncooled adsorption.

[0063] In various embodiments, the first data 402 indicates the priority with “1” the highest and it will always try to match the highest priority. The second data 404 indicates if the process needs to start (“O”) or stop (“X”) a heating / cooling, in which O must match with O and same for X. The third data 406 indicates the needed process is a heating (“2”) or cooling (“1”), and heating must match with a cooling process.

[0064] Table 2 illustrates an embodiment of how control signals sent may be parsed and read. Using this as an example for FIG. 4, the priority 1 is allocated, an X indicates a stop signal, and a 2 indicates a heating mode.Table 2 Signal matchingSignal ExplanationFor all priorities, it will try to match the highest priorities if possible.Priority (1st digit) (e.g., any signal tries to match priority 1 which is the highest and if not2, then 3, etc.)For a start signal (O) it must match a start signal (O) and vice versa (X Start / Stop (2nd digit) matches X). Because when there is a required heating (heat dischargeon condenser side) then the corresponding cooling on the evaporator can be utilized.Heating (1) must match with cooling (2) because when there is a Hat / Chn (3d dit)

[0065] Climatic conditions and / or seasonality may result in changes to the one or more properties of the ambient air. The one or more properties of ambient air may include, but not limited to, temperature, dry-bulb temperature, wet-bulb temperature, vapor pressure, relative humidity, specific humidity, dew point temperature, enthalpy and / or mixing ratio. Depending on the climate and / or season, there will be variation in the one or more properties of ambient air throughout the year. In particular, fluctuation in a temperature and / or a humidity level of the ambient air may affect the performance of the DAC system. Therefore, it is desirable to monitor the different properties of the ambient air.

[0066] According to another aspect of the disclosure, there is a computer program, the computer program comprising instructions to execute any method of controlling the direct air capture system. In some embodiments, there may comprise a non-transitory computer-readable medium configured to store executable software instructions thereon, such that when executed, performs the method of controlling each modular direct air capture unit based on the logic and flow in FIG. 4 and Table 1 and Table 2.

[0067] While the disclosure has been particularly shown and described with reference to specific embodiments, it should be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. The scope of the invention is thus indicated bythe appended claims and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced.

Claims

CLAIMS1. A direct air capture system (200) comprising:a plurality of direct air capture units (102, 202) configured to take in ambient air; the plurality of direct air capture units (102, 202) comprising a first direct air capture unit (202A) and a second direct air capture unit (202B);a fluid connection between the first direct air capture unit (202A) and the second direct air capture unit (202B) to facilitate thermal transfer therebetween, the fluid connection allowing a heat transfer fluid to flow therethrough;at least one branch controller (204), wherein the at least one branch controller (204) is configured to control each direct air capture unit (102, 202) of the plurality of direct air capture units (102, 202); and wherein the at least one branch controller (204) is configured to operate the first direct air capture unit (202A) and the second direct air capture unit (202B) in a desorption mode and an adsorption mode, or vice-versa, at the same time.

2. The direct air capture system (200) of claim 1, wherein each direct air capture unit (102, 202) of the plurality of direct air capture units comprise a cooling coil (210 A) for adsorption and a heating coil (210B) for desorption.

3. The direct air capture system (200) of claim 2, further comprising a branch controller (204A, 204B, 204C) associated with each direct air capture units (202A, 202B, 202C), and wherein each branch controller (204A, 204B, 204C) is configured to operate each direct air capture units (202A, 202B, 202C) based on a set of direct air capture properties, the direct aircapture properties comprising at least one of: an amount of moisture of ambient air, an adsorption capacity, a threshold of sorbent saturation and a completeness of desorption, or a combination thereof.

4. The direct air capture system (200) of claim 3, wherein each branch controller (204A, 204B, 204C) is configured to operate three times more direct air capture units (202B, 202C, 202D) in cooling mode than in heating mode (202 A).

5. The direct air capture system (200) of claim 3 or 4, wherein each branch controller (204A, 204B, 204C) is configured to send control signals to operate each direct air capture units (202A, 202B, 202C) in different modes, wherein the control signals comprise three data parts, wherein the first data part indicates the priority, the second data part indicates whether to start or stop and the third data part indicates whether the direct air capture unit should be in heating or cooling mode.

6. The direct air capture system (200) of claim 5, wherein the control signals are based on one of the following states: a sorbent breakthrough state, an end of adsorption state, an end of desorption state, and an end of air-cooling state, a cooled adsorption state and / or an uncooled adsorption state.

7. The direct air capture system (200) of any one of the preceding claims, wherein the plurality of direct air capture units (202) are configured for connection to a compressor (206) and an outdoor unit (208).

8. The direct air capture system (200) of any one of the preceding claims, wherein plurality of direct air capture units are used to cool down a data center.

9. The direct air capture system (200) of any one of the preceding claims,, wherein each direct air capture unit of the plurality of direct air capture units comprises a cooling coil for adsorption and a heating coil for desorption.

10. A method of providing a direct air capture system (200), comprising:configuring a plurality of direct air capture units (102, 202) to take in ambient air; the plurality of direct air capture units (102, 202) comprising a first direct air capture unit (202 A) and a second direct air capture unit (202B);providing a fluid connection between the first direct air capture unit (202A) and the second direct air capture unit (202B) to facilitate thermal transfer therebetween, the fluid connection allowing a heat transfer fluid to flow therethrough; andconfiguring at least one branch controller (204) to control each direct air capture unit (102, 202) of the plurality of direct air capture units (102, 202);operating the first direct air capture unit (202A) and the second direct air capture unit (202B) in a desorption mode and an adsorption mode, or vice-versa, at the same time by means of the at least one branch controller (204).

11. The method of claim 10, further comprises providing a branch controller (204A, 204B, 204C) associated with each direct air capture units (202A, 202B, 202C), and wherein each branch controller (204A, 204B, 204C) is configured to operate each direct air capture units (202A, 202B, 202C) based on a set of direct air capture properties, the direct air capture properties comprising at least one of an amount of moisture of ambient air, an adsorption capacity, a threshold of sorbent saturation and a completeness of desorption, or a combination thereof.

12. The method of claim 11, further comprises operating three times more direct air capture units (202B, 202C, 202D) in cooling mode than in heating mode (202A) by each branch controller (204A, 204B, 204C).

13. The method of claim 12, further comprises sending control signals by each branch controller (204A, 204B, 204C) to operate each direct air capture units (202A, 202B, 202C) in different modes, each control signal comprising three data parts, wherein the first data part indicates the priority, the second data part indicates whether to start or stop and the third data part indicates whether the direct air capture unit should be in heating or cooling mode.

14. The method of claim 13, wherein the control signals are based on one of the following states: a sorbent breakthrough state, an end of adsorption state, an end of desorption state, and an end of air-cooling state, a cooled adsorption state and / or an uncooled adsorption state.

15. The method of any one of claims 9 to 14, further comprises connecting the plurality of direct air capture units (202) with a compressor (206) and an outdoor unit (208), and wherein the heat transfer fluid is provided by the compressor (206) in the form of a refrigerant.

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