Systems and methods for operating a direct air carbon capture system intermittently based on energy availability

Abstract

Embodiments described herein relate to capturing CO2 emissions from the atmosphere. Methods and apparatus described herein can include a carbonation module configured to contact a gas stream containing CO2 with a carbonation medium such that the carbonation medium absorbs CO2 from the gas stream to produce a metal carbonate or a metal bicarbonate, a regenerator configured to heat the metal carbonate or the metal bicarbonate to release CO2 and regenerate the carbonation medium, and a control unit operably coupled to the carbonation module and the regenerator, the control unit configured to transfer (1) the carbonation medium from the regenerator to the carbonation module and (2) the metal carbonate or the metal bicarbonate from the carbonation module to the regenerator in response to changes in a supply of energy.

Description

Agent's File Ref. HRLM-007 / 01WD 342972-2046PROCESS AND METHODS FOR OPERATING A DIRECT AIRCARBON CAPTURE SYSTEM INTERMITTENTLY BASED ONENERGY AVAILABILITYCROSS-REFERENCE TO RELATED APPLICATIONS|0001 | This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 714,035, filed on October 30, 2024, and titled “Process And Methods For Operating a Direct Air Carbon Capture System Intermittently Based On Energy Availability,” which is incorporated by reference herein in its entirety.TECHNICAL FIELD[0002J Embodiments described herein relate to capture of carbon dioxide (CO2) from the atmosphere.BACKGROUND

[0003] The atmospheric concentration of CO2 has reached 420 parts per million by volume (ppm), an increase of almost 25 ppm in the last 10 years. As current emission levels exceed 37 GtCO2 / year, a diverse portfolio of CO2 mitigation technologies must be developed and strategically deployed to avoid a 2 °C increase in Earth's temperature above pre-industrial levels. Due to global reliance on fossil fuels, this portfolio must include technologies that can remove current and future CO2 emissions from the atmosphere, some of which include the acceleration of natural processes such as the CO2 uptake of oceans and the terrestrial biosphere (e.g., soils, forests, minerals, etc.), bioenergy with carbon capture and storage (BECCS), and synthetic approaches using chemicals also known as direct air capture (DAC) technologies.[0004| DAC is an important component of the global carbon management. Unlike pointsource carbon capture, which targets emissions at their origin, DAC systems extract carbon dioxide (CO2) directly from the atmosphere. As such, DAC systems are not necessarily restricted to certain sites (e.g., cement production plants) and can be quickly deployed at any number of locations for decarbonization purposes. DAC systems include a series of chemical processes that bind CO2 from the air to a sorbent material. The CO2 can then be removed from the sorbent and stored (e.g., permanently stored) geologically, or utilized to produce chemicals,1326537142Agent’s File Ref. HRLM-007 / 01WO 342972-2046 fuels, or other materials. For example, in some instances, a DAC system can use limestone as the sorbent due to the relative abundance and low cost of limestone. The DAC system can heat limestone (e.g., limestone composed primarily of calcium carbonate (CaCCh)) in a regenerator (e.g., kiln, calciner, reactor, etc.) to release CO2 and form calcium oxide (CaO), as shown in the chemical equation below:CaCO3+ energy -> CaO + CO2(1)

[0005] The CaO byproduct can be hydrated to produce calcium hydroxide (Ca(OH)2) which binds to atmospheric CO2 to regenerate CaCOs and thus remove CO2 from the atmosphere. The reaction of Ca(OH)2 binding the atmospheric CO2 effectively cleans the CO2 from the atmospheric air. This is an iterative process that can continue to draw down additional CO2 from the atmosphere. DAC systems typically use regenerators that require large amounts of energy to heat the sorbent material to release CO2. The inherently intermittent nature of the generation of many types of energy sources such as renewable wind and solar power, and their associated fluctuations in energy prices, can result in prohibitively high costs for the operation of a DAC systems. Consequently, there is a need in the field to develop DAC systems that can operate with variable energy sources achieving high energy efficiency and low cost.SUMMARY

[0006] Embodiments described herein relate to capturing and sequestering CO2 emissions from the atmosphere. In some embodiments, a system can include a carbonation module, a regenerator, and a control unit operably coupled to the carbonation module and the regenerator. The carbonation module can be configured to contact a gas stream containing CO2 with a carbonation medium such that the carbonation medium absorbs CO2 from the gas stream to produce a metal carbonate or a metal bicarbonate. The regenerator can be configured to heat the metal carbonate or the metal bicarbonate to release CO2 and regenerate the carbonation medium. The control unit can be configured to transfer (1) the carbonation medium from the regenerator to the carbonation module and (2) the metal carbonate or the metal bicarbonate from the carbonation module to the regenerator in response to changes in a supply of energy.BRIEF DESCRIPTION OF THE DRAWINGS

[0007] FIG. 1A is a block diagram of an example DAC system operating in a first mode, according to an embodiment.2326537142Agent’s File Ref. HRLM-007 / 01WD 342972-2046|0008| FIG. IB is a block diagram of the DAC system of FIG. 1 A operating in a second mode, according to an embodiment.DETAILED DESCRIPTION[0009[ Typically, DAC systems require high, continuous energy supply to maintain operations efficiency. In some instances, this can prove inefficient when energy sources fluctuate in energy production or price / cost. Some energy sources (e.g., renewable energy sources such as wind or solar) inherently provide intermittent energy' supply due to, for example, the weather. During periods of high energy generation from energy sources, there is a surplus of energy that can be unutilized or wasted. Alternatively, during periods of low energy generation from sources, there is shortage of energy input to the DAC system which can stall efficiency. Moreover, the processes of a DAC system have varying energy requirements, thereby further aggravating energy input fluctuations. The capture of CO2 requires relatively little energy compared to the release of CO2 from the sorbent (e.g., 85% - 95% of total system energy use) due to the electrical energy required to heat the calciner.

[0010] Some DAC system use battery storage solutions in order to store energy from the energy sources and prevent imposing a high energy demand on the grid. The use of battery systems to store energy' from energy' sources can increase capital investment to install and operate a operate a DAC system.

[0011] Methods described herein improve the efficiency and flexibility of mineral looping DAC systems by enabling load-following capability’. Methods described herein allow an example DAC system to operate continuously during favorable energy conditions and reduce or pause energy-intensive processes during peak demand or intermittent energy generation. Specifically, the example DAC system increases energy' consumption during periods of excess energy generation by running carbonation and calcination processes at full capacity. Conversely, the example DAC system decreases energy consumption during periods of peak demand or intermittent energy generation by idling the calcination process. As such, methods described herein maximize energy efficiency of energy sources by storing and processing materials when energy is cheapest. Further, methods described herein may not need expensive grid-level energy storage, which alleviates stress on the grid. For example, an example DAC system described herein adjusts energy consumption based on real-time grid demand by absorbing excess electricity during off-peak hours and absorbing less (i.e., idling) electricity use during peak demand. Thus, the example DAC system is an effective tool in demand-side3326537142Agent’s File Ref. HRLM-007 / 01WD 342972-2046 management, contributing to a more stable energy supply, reducing reliance on traditional backup generation or costly energy storage during peak times, having lower operational costs and better economic viability, reducing carbon footprint, etc. Additionally, the example DAC system described herein can enable the use of oversized calciners and material stockpiling so that sorbent regeneration can occur when energy is abundant and inexpensive.

[0012] In various embodiments, systems and methods are provided for capturing, concentrating, and regenerating CO2 using cyclic carbonation and regeneration reactions that are dynamically responsive to fluctuations in energy price and availability. The system generally includes a carbonation module, a regenerator, and a control unit that coordinates material and energy flow between these components.Carbonation Module

[0013] The carbonation module is configured to contact a C Ch-containing gas stream with a carbonation medium capable of chemically binding CO2 to form a metal carbonate or metal bicarbonate. The gas stream may include ambient air (in direct air capture or DAC applications), flue gas (typically containing 3-15 vol% CO2), or industrial process gases (containing up to 40 vol% CO2). The carbonation medium may be a metal oxide, metal hydroxide, or a pre-carbonated metal carbonate capable of reversible CO2 absorption and desorption. Exemplary carbonation media include calcium oxide (CaO), magnesium oxide (MgO), sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), sodium carbonate (Na2COs), and potassium carbonate (K2CO3).

[0014] During carbonation, these materials react with CO2 and, in the presence of moisture, may form metal carbonates or metal bicarbonates according to the following general reactions:CaO + CO2-> CaCO3Calcium carbonate') (2)Na2CO2+ H2O + CO2-> 2NaHCO2(Sodium bicarbonate) (3)Mg(0H)2+ CO2-> MgCO2+ H2(Magnesium carbonate) (4)

[0015] Reaction temperatures for carbonation may range from 10 °C to 200 °C. with a preferred range of 30 °C to 120 °C for hydroxide and carbonate media to balance kinetics and thermodynamic favorability. The partial pressure of CO2 in the contacting gas can range from 0.04 vol% (atmospheric) up to 30 vol%, and carbonation may occur at pressures from 0.8 to 2 bar absolute. The carbonation step can be conducted in a fixed-bed, moving-bed. or fluidized-4326537142Agent’s File Ref. HRLM-007 / 01WO 342972-2046 bed reactor, or via slurry' contact between a liquid-phase alkali solution and a gaseous CO2 stream.[0016| In certain embodiments, the carbonation module is continuously supplied with regenerated carbonation medium from the regenerator, while the carbonated product (e.g., CaCCh, NaHCOv or MgCCh) is intermittently or continuously removed for regeneration.Regenerator

[0017] The regenerator is configured to thermally decompose the metal carbonate or metal bicarbonate to release CO2 and regenerate the active carbonation medium. In many embodiments, the regenerator includes a calciner, which can operate as a rotary kiln, shaft furnace, fluidized-bed reactor, or indirectly heated electric calciner.100181 For calcium-based cycles, calcium carbonate (CaCOs) is decomposed at temperatures of approximately 850-950 °C, preferably around 900 °C, according to the reaction:CaCO3-> CaO + CO2(5)

[0019] For magnesium-based systems, magnesium carbonate (MgCCh) decomposes at lower temperatures, typically 350-700 °C, depending on the CO2 partial pressure. Sodium bicarbonate and potassium bicarbonate decompose at around 80-200 °C to yield the corresponding carbonate, water vapor, and CO2.[O02O| The regeneration step may be operated at pressures between 0.5 and 5 bar, for instance, and the CO2 released may be collected as a high-purity gas stream suitable for compression, utilization, or geological sequestration. The CO2 concentration is typically greater than 70% by volume, more preferably greater than 85%, and ideally greater than 95% on a dry basis, depending on process configuration and system airtightness. This high CO2 concentration enables efficient downstream handling without the need for large-scale amine or membrane capture systems. After regeneration, the CCh-rich gas may be post-processed through gas cleanup and conditioning steps that remove residual w ater vapor or trace oxygen or nitrogen. These steps can include condensation, adsorption, or catalytic polishing units. The purified CO2 stream is then compressed to transport or sequestration pressure and either routed to geological storage, mineralization, or utilization processes such as fuel synthesis or carbonation of industrial byproducts.5326537142Agent’s File Ref. HRLM-007 / 01WO 342972-2046|0021| The regeneration step may be operated at pressures between 0.5 and 5 bar, for instance, and the CO2 released may be collected as a high-purity gas stream suitable for compression, utilization, or geological sequestration. The CO2 concentration is ty pically greater than 70% by volume, more preferably greater than 85%, and ideally greater than 95% on a dry basis, depending on process configuration and system airtightness. This high CO2 concentration enables efficient downstream handling without the need for large-scale amine or membrane capture systems. After regeneration, the CCh-rich gas may be post-processed through gas cleanup and conditioning steps that remove residual water vapor or trace oxygen or nitrogen. These steps can include condensation, adsorption, or catalytic polishing units. The purified CO2 stream is then compressed to transport or sequestration pressure and either routed to geological storage, mineralization, or utilization processes such as fuel synthesis or carbonation of industrial byproducts.System Integration

[0022] The term contactor module may refer either to an individual contactor unit or, more broadly, to the collective arrangement of contactor units that together form the overall contactor architecture. For example, a single contactor module may comprise one contactor unit, while a multi-unit contactor architecture may include a plurality of such modules operated in parallel or series to achieve a desired overall capture rate. Similarly, the regeneration module may refer to a single calciner or hydrator unit, or collectively to the regeneration architecture comprising multiple calciners and hydrators operating in concert. This modular framework allows capacity to be scaled incrementally and enables independent operation, maintenance, or replacement of individual modules without requiring full system shutdown.

[0023] In certain embodiments, the regeneration system may be oversized relative to the carbonation system to accommodate periods of intermittent or constrained energy availability, such as during operation on variable renewable power. An oversized regenerator may operate at higher throughput during periods of abundant energy to build an inventory of regenerated solids (e.g., calcium oxide or hydroxide) that can be stored and later supplied to the contactor during lower-energy periods. This design enables temporal decoupling between the carbonation and regeneration processes, improving overall system flexibility and utilization. The relative sizing of the regenerator to the contactor may vary, for example, from approximately 1.1 times (e.g., l. lx) to over 10 times (e.g., lOx) the nominal steady-state throughput of the carbonation loop, depending on site-specific energy profiles, storage6326537142Agent’s File Ref. HRLM-007 / 01WG 342972-2046 capacity, and operational strategy'. In some embodiments, the regenerator is oversized relative to the carbonation module, by a factor of 1.1 to 2.0, and in some embodiments by 1.1, or 1.3 or 1.5, to accommodate transient increases in throughput when low-cost or surplus renewable energy is available.

[0024] Optional buffers or stockpile vessels may be positioned between modules to store intermediate solids. For example, a first buffer can hold calcium carbonate awaiting calcination, while a second buffer may hold regenerated calcium oxide or calcium hydroxide prior to recirculation to the carbonation module. The buffer capacity may correspond to 0. 1 to over 10,000 hours of steady -state system throughput, providing operational flexibility during periods of variable energy supply.

[0025] The system may further include a control unit configured to monitor, coordinate, and optimize operation of the carbonation and regeneration modules, as well as any intermediate buffers or storage vessels. In some embodiments, the control unit comprises one or more processors executing a control algorithm that adjusts process parameters - such as gas flow rate, solids circulation rate, calciner temperature, or module throughput - in response to real-time data on energy availability, CO2 capture rate, and system inventory levels. The control unit may receive input from sensors measuring temperature, pressure, flow, or composition at various points in the system, and may actuate valves, drives, or heaters to maintain desired operating conditions. In certain embodiments, the control unit interfaces with external signals such as electricity' price forecasts, renewable generation output, or grid dispatch instructions, allowing dynamic modulation of regeneration activity to minimize energy cost or maximize utilization of low-carbon power. The control unit may be implemented as a distributed control system (DCS), a supervisory control and data acquisition (SCADA) platform, or a cloud-based optimization layer employing predictive or machinelearning algorithms to continuously refine operating setpoints based on historical performance and forecasted conditions.

[0026] A control unit operably connects the carbonation and regeneration modules, dynamically adjusting material and energy flow in response to real-time energy supply conditions. The control logic may reference price signals, energy availability metrics, or renewable generation forecasts. For instance, when the price of electricity exceeds a first threshold (e.g., $60 per Megawatt hour (MWh), $80 per MWh, $100 perMWh, $120 per MWh, $200 per MWh, or $500 per MWh), the control unit may reduce calciner throughput or enter a standby mode, whereas when the price drops below a second threshold (e.g., $10 per MWh,7326537142Agent’s File Ref. HRLM-007 / 01WO 342972-2046$25 per MWh, $40 per MWh, or $60 per MWh), the system may increase throughput or fully utilize available regeneration capacity.

[0027] Similarly, the control unit may reduce throughput when renewable generation availability (such as solar irradiance or wind capacity factor) falls below 30-50% of nominal output, and increase throughput when it exceeds 70-90%. The calciner may be operated intermittently, or held at a standby temperature (e.g., 200-800 °C) to allow rapid resumption of operation with minimal thermal cycling stress.

[0028] In some embodiments, the control system directs energy flow between a behind- the-meter renewable energy source and the electrical grid. When energy prices on the grid exceed a specified export threshold, excess renewable electricity (e.g., from on-site solar PV) may be diverted to the grid. Conversely, when prices fall below the import threshold, the regenerator may draw from the grid to take advantage of low-cost, low-carbon electricity.Energy Sources and Variability

[0029] The system is particularly suited for integration with variable low-carbon energy sources, including wind, solar photovoltaic, geothermal, hydroelectric, and nuclear energy. These sources exhibit inherent temporal variability, which the system leverages by modulating regeneration activity according to energy availability across multiple timescales. For example, a facility co-located with a 100 megawatt (MW) wind farm may operate the carbonation module continuously while varying the calciner throughput between approximately 25% and 100% in response to real-time wind generation. Similarly, a solar-powered calciner may operate at full capacity during daylight hours (e.g., 8-10 hours per day) and pause or maintain standby temperature at night. Over longer timescales, the system may also accommodate seasonal variability in renewable energy' supply — for instance, increasing regeneration activity during summer months with higher solar irradiance, or during windy winter periods, and reducing regeneration throughput during low-generation seasons. Such flexibility enables high utilization of variable low-carbon energy while maintaining continuous CO2 capture through buffered or stored solids.

[0030] Energy pricing in low-carbon grids often reflects this variability', with wholesale electricity' prices fluctuating from negative values (-$10 / MWh) during oversupply to peak values exceeding $200 / MWh during scarcity events. Time-of-use optimization can therefore yield significant cost reductions by regenerating CO2 only when prices are low or renewable output is high. In certain embodiments, the system may be integrated with battery energy8326537142Agent’s File Ref. HRLM-007 / 01WO 342972-2046 storage, such as lithium-ion or flow batteries, allowing short-term buffering of power for continuous operation of control and auxiliary systems.[0031 | This dynamic operation provides a pathway to dispatchable carbon removal, wherein CO2 capture and release are temporally decoupled but energetically synchronized with the evolving structure of renewable energy markets. The approach enables lower-cost, lower- carbon CO2 management with flexibility suitable for large-scale deployment.

[0032] As used herein, “stream” can refer to a How of a material, where the material may t include a solid, a liquid, and / or gas. For example, a stream can include a solid in granular form conveyed on a conveyor device. A stream can also include a liquid and / or gas flowing through a pipe. A stream can include a solution and / or a dispersion of a solid in a liquid or a gas.

[0033] As used in this specification, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, the term “a member” is intended to mean a single member or a combination of members, “a material” is intended to mean one or more materials, or a combination thereof.

[0034] The term “substantially” when used in connection with “cylindrical,” “linear,” and / or other geometric relationships is intended to convey that the structure so defined is nominally cylindrical, linear or the like. As one example, a portion of a support member that is described as being “substantially linear” is intended to convey that, although linearity of the portion is desirable, some non-linearity' can occur in a “substantially linear” portion. Such nonlinearity can result from manufacturing tolerances, or other practical considerations (such as, for example, the pressure or force applied to the support member). Thus, a geometric construction modified by the term “substantially” includes such geometric properties within a tolerance of plus or minus 5% of the stated geometric construction. For example, a “substantially linear” portion is a portion that defines an axis or center line that is within plus or minus 5% of being linear.

[0035] As used herein, the term “set” and “plurality” can refer to multiple features or a singular feature with multiple parts. For example, when referring to a set of electrodes, the set of electrodes can be considered as one electrode with multiple portions, or the set of electrodes can be considered as multiple, distinct electrodes. Additionally, for example, when referring to a plurality of electrochemical cells, the plurality' of electrochemical cells can be considered as multiple, distinct electrochemical cells or as one electrochemical cell with multiple portions.9326537142Agent’s File Ref. HRLM-007 / 01WG 342972-2046Thus, a set of portions or a plurality of portions may include multiple portions that are either continuous or discontinuous from each other. A plurality of particles or a plurality of materials can also be fabricated from multiple items that are produced separately and are later joined together (e.g., via mixing, an adhesive, or any suitable method).

[0036] FIG. 1A is a block diagram of a DAC system 100 that captures CO2 from a gas stream containing CO2 operating in a first modality, according to an embodiment. In some implementations, the DAC system 100 (also referred to herein as the system 100) can capture CO2 from atmospheric air (e.g., the gas stream containing CO2 can be ambient air). In other implementations the system 100 can capture CO2 from other sources such as biogenic sources (e.g., fermentation or bioenergy with carbon capture storage (BECCS)), industrial sources (e.g., cement or steel), and / or the like (e.g., the gas stream can be any suitable gas which contains CO2). FIG. 1 A shows the DAC system 100 includes a carbonation module 110, a regenerator 120, and a control unit 130 operably coupled to the carbonation module 110 and the regenerator 120. Optionally, in some embodiments the system 100 can include a carbonated material storage component 140, a carbonation medium storage component 150, and a sequestration / utilization space 160. The carbonation module 110 can be configured to contact an incoming gas stream containing CO2 with a carbonation medium such as CaO or Ca(OH)2 which can absorb CO2 included in the incoming gas stream and produce a carbonated material such as a metal carbonate (e.g., CaCCh) or a metal bicarbonate. The carbonation module 110 releases an outgoing gas stream having a concentration of CO2 lower than the incoming gas stream. In some implementations, when the gas stream is atmospheric air, the outgoing gas stream can be air without CO2 (i.e., cleaned air) which can be released back into the atmosphere. The regenerator 120 can be configured to receive the carbonated material and heat the carbonated material to release the CO2 and regenerate the carbonation medium. In some embodiments, the regenerator 120 can be a kiln that heats the carbonated material to (i) release CO2 and (ii) regenerate the carbonation medium to cycle back to the process. The regenerated carbonation medium from the regenerator 120 can be routed back to the carbonation module 110 to continue capturing CO2, restarting the iterative process. The sequestration / utilization space 160 can store the CO2 released from the regenerator 120. In some embodiments, the CO2 in the sequestration / utilization space 160 can be utilized to produce fuel, chemicals, or other materials. FIG. 1 A illustrates a first mode and / or modality of operating the system 100 when energy (e.g., from the grid or low-carbon energy) is in excess or is otherwise available. As shown in FIG 1A, the system 100 can direct the operation of the10326537142Agent’s File Ref. HRLM-007 / 01WG 342972-2046 carbonation module 110 and the regenerator 120 such that the carbonation medium is transferred from the regenerator 120 to the carbonation module 110 continuously while the carbonated material is transferred from the carbonation module 110 to the regenerator 120 continuously. In some embodiments in which the system 100 includes the optional carbonated material storage component 140, the control unit 130 can facilitate the transfer of carbonated material from the carbonation module to the carbonated material storage component 140, and then from the carbonated material storage component 140 to the regenerator 120. Similarly, in some embodiments in which the system 100 includes a carbonation medium storage component 150, the control unit 130 can facilitate the transfer of carbonation medium from the regenerator to the carbonation medium storage component 150, and then from the carbonation medium storage component 150 to the carbonation module 110.

[0037] In FIG. 1 A. the regenerator 120 needs energy to heat the carbonated material in the regenerator 120. When energy is abundant, the system 100 can stockpile carbonation medium for use in situations where the energy supply is limited and / or the regenerator 120 is idling or turned off. In FIG. 1 A, the system 100 can stockpile, store, provide, etc., carbonation medium in the carbonation medium storage component 150 when energy' is abundant. Similarly, when either the grid energy or the low-carbon energy is abundant, the system 100 can stockpile carbonated material for use in situations where energy supply is limited. The system 100 can stockpile, store, provide, etc., the excess carbonated material in the carbonated material storage component 140 when energy is abundant. In some examples, the regenerator 120 can access the excess carbonated material in the carbonated material storage component 140 for subsequent heating and regeneration purposes. In some embodiments, the sorbent and / or the excess carbonated material can be stored in mineral silos, piles, etc.[0038| FIG. IB is a block diagram of the direct air carbon capture system 100 that captures CO2 from atmospheric air operating in a second modality, according to an embodiment. As described above, in some implementations the system 100 can capture CO2 from atmospheric air (e.g., the gas stream containing CO2 can be ambient air). In other implementations, the system 100 can capture CO2 from other sources such as biogenic sources (e.g., fermentation or bioenergy with carbon capture storage (BECCS)), industrial sources (e.g., cement or steel), and / or the like. FIG. IB illustrates a second mode and / or modality of operating the system 100 when energy (e.g., from the grid or low-carbon energy) is in short supply, unavailable, or costly (e.g.. during winter months). Due to the limited energy available, the regenerator 120 may not have sufficient energy to heat the carbonated material. Without heating the carbonated11326537142Agent’s File Ref. HRLM-007 / 01WG 342972-2046 material, the system 100 is limited from providing carbonation medium back to the carbonation module 110 to continue removing CO2 from the gas stream, as described in connection with FIG. 1A. However, during the abundant energy situation of FIG. 1A, the regenerator 120 can stockpile excess carbonation material in the carbonation medium storage component 150. As such, during the limited energy7situation of FIG. IB, the carbonation module 110 can access the carbonation medium from the carbonation medium storage component 150 while the regenerator 120 is idling or turned off (due to limited energy' supply). Further, the carbonation module 110 can stockpile any' excess carbonated material in the carbonated material storage component 140 (since the regenerator 120 may be turned off or otherwise unable to store the excess carbonated material). In some embodiments, the control unit 130 of the system 100 includes software or other instructions to monitor the grid or low-carbon energy sources for bandwidth, availability7, costs, etc., to optimize operation between the first mode (described in connection with FIG. 1A) and the second mode (described in connection with FIG. IB). Key systems like energy management, process control, predictive analytics, and Supervisory Control and Data Acquisition (SCAD A) can manage the load-following operations of methods described herein.100391 Various concepts may be embodied as one or more methods, of which at least one example has been provided. The acts performed as part of the method may be ordered in any suitable way. Accordingly, embodiments may be constructed in which acts are performed in an order different than illustrated, which may include performing some acts simultaneously, even though shown as sequential acts in illustrative embodiments. Put differently, it is to be understood that such features may not necessarily be limited to a particular order of execution, but rather, any number of threads, processes, services, servers, and / or the like that may execute serially, asynchronously, concurrently, in parallel, simultaneously, synchronously, and / or the like in a manner consistent with the disclosure. As such, some of these features may be mutually contradictory, in that they cannot be simultaneously present in a single embodiment. Similarly, some features are applicable to one aspect of the innovations, and inapplicable to others.

[0040] In addition, the disclosure may include other innovations not presently described. The Applicant reserves all rights in such innovations, including the right to embodiment such innovations, file additional applications, continuations, continuations-in-part, divisionals, and / or the like thereof. As such, it should be understood that advantages, embodiments, examples, functional, features, logical, operational, organizational, structural, topological,12326537142Agent’s File Ref. HRLM-007 / 01WG 342972-2046 and / or other aspects of the disclosure are not to be considered limitations on the disclosure as defined by the embodiments or limitations on equivalents to the embodiments. Depending on the particular desires and / or characteristics of an individual and / or enterprise user, database configuration and / or relational model, datatype, data transmission and / or network framework, syntax structure, and / or the like, various embodiments of the technology7disclosed herein maybe implemented in a manner that enables a great deal of flexibility and customization as described herein.

[0041] All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and / or ordinary meanings of the defined terms.

[0042] As used herein, in particular embodiments, the terms “about” or “approximately” when preceding a numerical value indicates the value plus or minus a range of 10%. Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limit of that range and any other stated or intervening value in that stated range is encompassed within the disclosure. That the upper and lower limits of these smaller ranges can independently be included in the smaller ranges is also encompassed within the disclosure, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the disclosure.

[0043] The phrase “and / or,” as used herein in the specification and in the embodiments, should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Multiple elements listed with “and / or” should be construed in the same fashion, i.e., “one or more” of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the “and / or” clause, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, a reference to “A and / or B”, when used in conjunction with open-ended language such as “comprising” can refer, in one embodiment, to A only (optionally including elements other than B); in another embodiment, to B only (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc.13326537142Agent’s File Ref. HRLM-007 / 01WO 342972-2046|0044| As used herein in the specification and in the embodiments, ‘"or” should be understood to have the same meaning as “and / or” as defined above. For example, when separating items in a list, “or” or “and / or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary', such as “only- one of’ or “exactly one of,” or, when used in the embodiments, “consisting of,” will refer to the inclusion of exactly one element of a number or list of elements. In general, the term “or” as used herein shall only be interpreted as indicating exclusive alternatives (i.e., “one or the other but not both”) when preceded by terms of exclusivity7, such as “either,” “one of,” “only one of,” or “exactly one of.” “Consisting essentially of,” when used in the embodiments, shall have its ordinary meaning as used in the field of patent law.

[0045] As used herein in the specification and in the embodiments, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every7element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, “at least one of A and B” (or, equivalently, “at least one of A or B,” or, equivalently “at least one of A and / or B”) can refer, in one embodiment, to at least one. optionally including more than one, A, with no B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc.

[0046] In the embodiments, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” “composed of,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of’ and “consisting essentially of’ shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures, Section 2111.03.14326537142Agent’s File Ref. HRLM-007 / 01WD 342972-2046|0047| While specific embodiments of the present disclosure have been outlined above, many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, the embodiments set forth herein are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the disclosure. Where methods and steps described above indicate certain events occurring in a certain order, those of ordinary skill in the art having the benefit of this disclosure would recognize that the ordering of certain steps may be modified and such modification are in accordance with the variations of the invention. Additionally, certain of the steps may be performed concurrently in a parallel process when possible, as well as performed sequentially as described above. The embodiments have been particularly shown and described, but it will be understood that various changes in form and details may be madeEXAMPLESExample 1:

[0048] Solar-driven operation with diurnal modulation. In one embodiment, a DAC facility configured for 1 MTA net CO2 removal is co-located with a 500 MW solar photovoltaic array. The carbonation system operates continuously, while the regeneration system (e.g., a high-temperature calciner) is designed for 2x nominal throughput capacity7to align operation with daylight availability7. During approximately 8-10 hours of daytime solar generation, the calciner operates at full capacity to regenerate calcium oxide and replenish a solids buffer. At night, regeneration pauses or turns down while the contactor continues operating using stored solids. Assuming solar electricity costs of US $20 / MWh and grid backup at US $80 / MWh, the optimized dispatch strategy reduces average regeneration energy cost by over 40% compared to steady -state grid operation.Example 2:[0049| Wind-powered operation with real-time load following. In another embodiment, a 1 MTA DAC system is integrated with a 250 MW onshore wind facility characterized by power output fluctuations between 25% and 100% of rated capacity. The regenerator is oversized by 1.5x relative to the carbonation loop and dynamically modulates calcination throughput in proportion to instantaneous wind generation. When wind power is abundant, the system increases calcination rate and stores regenerated solids; when power is low, the calciner idles and the contactor continues drawing from storage. With wind electricity priced at US $25- 35 / MWh during high-output periods and US $70 / MWh during low-output periods, this control15326537142Agent’s File Ref. HRLM-007 / 01WD 342972-2046 strategy achieves equivalent CO2 removal at 20-30% lower energy cost than constant-output operation.Example 3:

[0050] Seasonal variability' and regenerator oversizing. In a further embodiment, the system is located in a region with strong seasonal variation in renewable availability’, such as northern Europe, where winter wind generation is 2-3 times higher than summer output. The regeneration system is therefore sized to 3 times (e.g., 3x) the steady-state throughput of the carbonation loop, enabling stockpiling of regenerated solids during high-wind winter months. These solids are stored and consumed during summer, allowing year-round operation of the contactor at 1 MTA CO2 removal. Assuming average winter electricity prices of US $25 / MWh and summer prices of US $80 / MWh, this seasonal load-shifting strategy reduces annualized energy costs by approximately 35%, while maintaining continuous net removal with minimal curtailment.Example 4:

[0051] Hybrid solar-grid operation with price-based dispatch. In yet another embodiment, a 1 MTA DAC system operates in a grid with dynamic pricing that varies hourly between US $15 / MWh (off-peak midday solar) and US $120 / MWh (evening peak). The regeneration module is sized to 2 times (e.g., 2x) nominal capacity and configured to operate preferentially during hours with electricity7prices below7US $40 / MWh, producing excess regenerated solids for later use. During peak-price periods, the calciner remains idle while the carbonation process continues using buffered material. Modelled dispatch optimization over a representative year shows a 45% reduction in average energy cost per tonne of CO2 removed, while maintaining steady overall annual capture.Example 5:[00521 Grid-connected operation under a power purchase agreement (PPA). In another embodiment, a 1 MTA DAC facility operates using grid electricity supplied under a hybrid pow7er purchase agreement combining a fixed renew able tranche and variable market exposure. The facility' secures a 15-year PPA for 100 MW of baseload wind and solar power at a fixed price of US $35 / MWh. while retaining the option to draw additional power from the grid during low-price periods and curtail consumption during price spikes. The regeneration module is sized to 1.5x the nominal carbonation capacity, enabling flexible operation to exploit price volatility. During off-peak hours (e.g., night or high-wind conditions) when spot prices fall16326537142Agent’s File Ref. HRLM-007 / 01WD 342972-2046 below US $30 / MWh, the calciner operates at elevated throughput to build a solids buffer. During peak hours when prices exceed US $100 / MWh, regeneration pauses, and the contactor continues operation using stored regenerated solids. Dispatch modeling for a representative year demonstrates that this hybrid PPA approach can reduce net energy cost per tonne of CO2 removed by 25-40%, while providing stable, contract-backed revenue predictability for the renewable power supplier and ensuring continuous DAC operation.17326537142

Claims

Agent’s File Ref. HRLM-007 / 01WO 342972-2046CLAIMS1. A system, comprising: a carbonation module configured to contact a gas stream containing CO2 with a carbonation medium such that the carbonation medium absorbs CO2 from the gas stream to produce a metal carbonate or a metal bicarbonate; a regenerator configured to heat the metal carbonate or the metal bicarbonate to release CO2 and regenerate the carbonation medium; and a control unit operably coupled to the carbonation module and the regenerator, the control unit configured to transfer (1) the carbonation medium from the regenerator to the carbonation module and (2) the metal carbonate or the metal bicarbonate from the carbonation module to the regenerator in response to changes in a supply of energy.

2. The system of claim 1, wherein the control unit is configured to (1) reduce throughput through the regenerator when a price of energy exceeds a first threshold setpoint or (2) increase throughput through the regenerator when the price of the energy falls below a second threshold setpoint.

3. The system of claim 1. wherein the control unit is configured to (1) reduce throughput through the regenerator when an aval 1 abi 1 ity of energy falls below a first threshold setpoint or (2) increase throughput through the regenerator when the availability of energy exceeds a second threshold setpoint.

4. The system of claim 1, wherein the regenerator includes a calciner.

5. The system of claim 4. wherein the control unit is configured to (1) reduce throughput through the calciner when a price of energy exceeds a first threshold setpoint or (2) increase throughput through the calciner when the price of energy falls below a second threshold setpoint.

6. The system of claim 4, wherein the control unit is configured to (1) reduce throughput through the calciner when an availability of energy falls below a first threshold setpoint or (2) increase throughput through the calciner when the availability of energy exceeds a second threshold setpoint.18326537142Agent’s File Ref. HRLM-007 / 01WO 342972-20467. The system of claim 4, wherein the control unit operates the calciner intermittently.

8. The system of claim 4, wherein the control unit holds the calciner at an operational temperature and pauses a feed of the metal carbonate or the metal bicarbonate to the calciner.

9. The system of claim 4, wherein the control unit holds the calciner at a reduced temperature and pauses a feed of the metal carbonate or the metal bicarbonate to the calciner.

10. The system of claim 1, wherein the energy includes one or more of wind, solar, hydro, nuclear, or geothermal energy.

11. The system of claim 1 , wherein the energy is draw n at least in part from the grid.

12. The system of claim 1, wherein the energy is draw n at least in part from a battery.

13. The system of claim 1, wherein the energy is drawn at least in part from a behind-the- meter energy' facility7.

14. The system of claim 1, wherein the control unit directs energy from a behind-the-meter energy facility to the grid when a price of energy exceeds a threshold setpoint.

15. The system of claim 1 , wherein the carbonation medium comprises a metal oxide, metal hydroxide, or metal carbonate.

16. The system of claim 15, wherein the metal is calcium, sodium, magnesium, or potassium.

17. A system, comprising: a carbonation module configured to react a carbonation medium with CO2 to form a metal carbonate or metal bicarbonate; a regenerator configured to heat the metal carbonate or metal bicarbonate in a calciner to release CO2. wherein the regenerator is sized to accommodate a higher throughput than the carbonation module.19326537142Agent’s File Ref. HRLM-007 / 01WO 342972-204618. The system of claim 17, wherein the calciner is oversized.

19. The system of claim 18, wherein the calciner is oversized by a factor of at least 1.1.

20. The system of claim 18, wherein the calciner is oversized by a factor of at least 1.3.

21. The system of claim 18, wherein the calciner is oversized by a factor of at least 1.5.

22. The system of claim 17, wherein the regenerator includes an oversized hydrator.

23. The system of claim 17, further comprising a buffer between the carbonation module and the regenerator to stockpile material prior to introduction to the regeneration system.

24. The system of claim 23, wherein the material is a metal carbonate or metal bicarbonate.

25. The system of claim 17, further comprising a buffer between the regenerator and the carbonation module to stockpile material prior to introduction to the carbonation module.

26. The system of claim 25, wherein the material is metal oxide, metal hydroxide, or metal bicarbonate.

27. A method for load following in a CO2 capture system comprising a carbonation module configured to react a carbonation medium with CO2 to form a metal carbonate or a metal bicarbonate, a regenerator that heats the metal carbonate or the metal bicarbonate in a calciner to release CO2, and a control unit that dynamically adjusts operations in response to real-time changes in supply of energy, the method comprising: reducing throughput through the regenerator when a price of energy exceeds a first threshold setpoint or increasing throughput through the regenerator when the price of energy falls below a second threshold setpoint; or reducing throughput through the regenerator when an availability of energy falls below a first threshold setpoint or increasing throughput through the regenerator when the availability of energy exceeds a second threshold setpoint.

28. The method of claim 27, wherein the regenerator includes a calciner.20326537142Agent’s File Ref. HRLM-007 / 01WO 342972-204629. The method of claim 28, wherein the control unit reduces throughput through the calciner when the price of energy exceeds a first threshold setpoint or increases throughput through the calciner when the price of energy falls below a second threshold setpoint.

30. The method of claim 28, wherein the control unit reduces throughput through the calciner when the availability of energy falls below' a first threshold setpoint or increases throughput through the calciner when the availability' of energy exceeds a second threshold setpoint.

31. The method of claim 28, wherein the control unit operates the calciner intermittently.

32. The method of claim 28, wherein the control unit configured to hold the calciner at an operational temperature and pauses a feed of the metal carbonate or the metal bicarbonate to the calciner.

33. The method of claim 28, wherein the control unit is configured to hold the calciner at a reduced temperature and pauses a feed of the metal carbonate or the metal bicarbonate to the calciner.

34. The method of claim 27, wherein the energy' comprises one or more of wind, solar, hydro, nuclear, or geothermal energy.

35. The method of claim 27, wherein the energy is drawn at least in part from the grid.

36. The method of claim 27, w'herein the energy is draw n at least in part from a battery.21326537142

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