A self-powered solar-powered air-water extraction coupled hydrogen production system

Abstract

This invention relates to the field of hydrogen production technology, specifically to a self-driven solar-powered air-water extraction coupled hydrogen production system. The system includes a photovoltaic-thermal module, an air-water extraction module, a mass transfer driving module, and an electrolysis hydrogen production module. The photovoltaic-thermal module includes a solar panel and a thermally conductive layer. The air-water extraction module includes a moisture-absorbing cloth soaked in a hygroscopic salt solution. The mass transfer driving module includes a first solution tank and a second solution tank with a height difference. The electrolysis hydrogen production module includes an alkaline electrolyzer, inside which are arranged an alkaline electrolyte, an anode, a cathode, and an alkaline electrolysis membrane. A hydrophobic and breathable membrane is located between the evaporation unit and the alkaline electrolyte, and the two ends of the moisture-absorbing cloth are in contact with the liquid surfaces inside the first and second solution tanks, respectively. This system requires no condensation stage, has no moving parts, maintains a stable electrolyte state, and can achieve self-driven operation, thus meeting the urgent need for large-scale deployment of solar-powered air-water extraction hydrogen production technology.

Description

Technical Field

[0001] This invention relates to the field of hydrogen production technology, specifically to a self-driven solar-powered air-water extraction coupled hydrogen production system. Background Technology

[0002] Hydrogen energy is a clean and high-energy-density secondary energy source, playing a crucial role in the global energy transition. Utilizing renewable energy for water electrolysis to produce green hydrogen is a key technological pathway to achieving zero-carbon emission development goals, with wide applications in distributed energy supply in arid regions, hydrogen production in water-scarce outdoor scenarios, and hydrogen refueling in remote areas. Currently, solar-driven air-water harvesting coupled with electrolysis for hydrogen production has become a mainstream research direction for overcoming the spatial mismatch limitations of water resources. Related technologies mainly revolve around the synergistic operation of water collection using adsorption materials and hydrogen supply from the electrolyzer.

[0003] Current solar-powered air-to-water coupling hydrogen production technologies generally employ an adsorption-condensation combined with electrolysis approach. This approach uses silica gel or metal-organic framework materials as adsorbents to absorb moisture from the ambient air at night. During the day, solar heating enables desorption, and the resulting water vapor is converted into liquid water via a condenser. The liquid water is then stored and transported to an electrolyzer to ultimately complete the electrolytic hydrogen production process. This technology has been tested on a large scale in both low-humidity and high-temperature environments.

[0004] However, the aforementioned technical solutions suffer from several inherent drawbacks that are difficult to overcome. The condensation process of water vapor releases a large amount of latent heat, which is directly dissipated to the outside, resulting in significant energy waste. The condensation operation requires cooling the water vapor to below the dew point temperature, which is difficult to achieve stably in low humidity or high temperature environments. The desorption of traditional adsorption materials requires relatively high temperatures, which are difficult to match with the temperature of conventional solar collectors, leading to a significant decrease in water extraction efficiency. The system requires a condenser, water storage tank, water pump, and heat dissipation fins, resulting in a complex and bulky overall structure.

[0005] Furthermore, existing technologies suffer from insufficient electrolyte stability and high difficulty in dynamic matching. Alkaline electrolytes readily react with carbon dioxide in the air under open conditions, forming carbonates that degrade the electrolyte and passivate the electrodes. The rate of water intake from the air fluctuates with ambient humidity, and the rate of hydrogen production by electrolysis fluctuates with light intensity. Both require active control components such as sensors, valves, and pumps to achieve matched operation, increasing the risk of system failure and maintenance costs.

[0006] As the demand for green hydrogen energy continues to increase in arid and water-scarce regions, the industry is placing higher demands on the environmental adaptability, structural simplicity, and operational stability of hydrogen production systems. Summary of the Invention

[0007] To overcome the shortcomings of existing technologies, this application provides a self-driven solar-powered air-to-water hydrogen production system. This system requires no condensation stage, has no moving parts, maintains a stable electrolyte state, and can achieve self-driven operation, thus meeting the urgent need for large-scale deployment of solar-powered air-to-water hydrogen production technology.

[0008] To achieve the above objectives, the present invention provides a self-driven solar-powered air-water extraction coupled hydrogen production system.

[0009] The system includes a photovoltaic-thermal module, an air-water extraction module, a mass transfer-driven module, and an electrolytic hydrogen production module. The photovoltaic-thermal module includes a solar panel and a thermally conductive layer, with one side of the thermally conductive layer in contact with the solar panel. The air-water extraction module includes a moisture-absorbing cloth soaked in a hygroscopic salt solution, divided into a moisture-absorbing unit and an evaporation unit. The other side of the thermally conductive layer is in contact with the evaporation unit, and a hydrophobic and breathable membrane is positioned below the moisture-absorbing cloth. The mass transfer-driven module includes a first solution tank and a second solution tank with a height difference. The electrolytic hydrogen production module includes an alkaline electrolyzer, which contains an alkaline electrolyte, an anode, a cathode, and an alkaline electrolytic membrane. The hydrophobic and breathable membrane is located between the evaporation unit and the alkaline electrolyte, and both ends of the moisture-absorbing cloth are in contact with the liquid surfaces inside the first and second solution tanks, respectively.

[0010] Preferably, a photoelectric conversion area is arranged on the surface of the solar panel, and a thermally conductive layer is fixedly attached to the back of the solar panel.

[0011] Preferably, the output end of the photovoltaic thermal module is electrically connected to the alkaline electrolytic cell.

[0012] Preferably, the absorbent cloth has a continuous capillary transmission channel inside, which connects the absorbent unit and the evaporation unit.

[0013] Preferably, an air gap is provided between the hydrophobic and breathable membrane and the evaporation unit.

[0014] Preferably, a liquid guide pipe or circulation device is provided between the first solution tank and the second solution tank to connect the hygroscopic salt solution inside the two solution tanks.

[0015] Preferably, the anode is located at the upper part of the alkaline electrolytic cell, the cathode is located at the lower part of the alkaline electrolytic cell, and the alkaline electrolytic diaphragm is disposed between the anode and the cathode.

[0016] Preferably, the alkaline electrolytic membrane is a polyphenylene sulfide membrane, a polyether ether ketone membrane, or a composite membrane.

[0017] Preferably, the hygroscopic salt solution is a lithium chloride solution, and the alkaline electrolyte is a potassium hydroxide solution.

[0018] Preferably, the photovoltaic thermal module, the air-water intake module, the mass transfer drive module, and the electrolysis hydrogen production module are stacked in sequence to form an integrated hydrogen production unit.

[0019] Compared with other technologies, the beneficial effects of this application are as follows: Firstly, in terms of technical performance, this invention overcomes the shortcomings of existing air-to-water hydrogen production systems, such as large latent heat loss from condensation and poor adaptability to low-humidity environments, by using a dual-salt solution vapor pressure difference drive and a direct mass transfer design without condensation. This significantly improves the driving force for water vapor transport and greatly enhances the system's energy utilization efficiency. The combination of a closed structure and a hydrophobic, breathable membrane isolates external carbon dioxide and impurities, preventing electrolyte deterioration and electrode passivation, maintaining long-term stable operation of the electrolysis process. Simultaneously, it eliminates the need for auxiliary components such as condensers, water storage devices, and water pumps, making the system structure more compact and reliable.

[0020] Secondly, in terms of economy and operation, this invention utilizes height difference and capillary force to achieve passive moisture transfer, coupled with a self-regulating solution concentration mechanism. It eliminates the need for active control components such as sensors, valves, and pumps, effectively reducing system failure rate and maintenance costs, and achieving fully passive operation without external intervention. The photovoltaic-thermal full-spectrum coupling utilization method can simultaneously complete photoelectric conversion and photothermal desorption, improving the overall utilization rate of solar energy. The hygroscopic materials and alkaline electrolyte used are all conventional industrial raw materials, resulting in low overall preparation costs and good economic efficiency.

[0021] Furthermore, this invention can stably produce hydrogen in environments with low humidity, drought, and lack of external water sources, overcoming the dual limitations of traditional systems on environmental humidity and water resources, and broadening the applicable scenarios for solar-powered hydrogen production. Its modular integrated design facilitates mass production and parallel expansion, meeting diverse needs such as distributed hydrogen production, field energy supply, and hydrogen refueling in remote areas. It aligns with the large-scale development of green hydrogen energy and the dual-carbon policy orientation, possessing broad prospects for industrial application. Attached Figure Description

[0022] This application can be better understood by describing its embodiments in conjunction with the accompanying drawings, in which: Figure 1 This is a schematic diagram of a self-driven solar-powered air-water extraction coupled hydrogen production system according to this application.

[0023] Explanation of icon numbers: 11. Solar panel; 12. Photovoltaic conversion area; 13. Thermal conductive layer; 14. Wire; 21. Moisture-absorbing cloth; 211. High-temperature section; 212. Low-temperature section; 22. Hydrophobic and breathable membrane; 23. Air gap; 31. First solution tank; 32. Second solution tank; 41. Alkaline electrolyte; 42. Anode; 43. Alkaline electrolytic membrane; 44. Cathode. Detailed Implementation

[0024] Unless otherwise defined, the technical or scientific terms used in this specification and claims shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0025] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0026] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0027] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. They can refer to a mechanical connection or an electrical connection. They can refer to a direct connection or an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] This invention provides a method such as Figure 1 The self-driven solar-powered air-water extraction coupled hydrogen production system is shown. This system can achieve integrated operation of air-water extraction and electrolysis hydrogen production without an external water source or active control components. It solves the problems of high condensation energy consumption, easy deterioration of electrolyte, and poor environmental adaptability of traditional water extraction hydrogen production technology. The overall structure is compact and has high energy utilization.

[0030] The self-driven solar-powered air-water extraction coupled hydrogen production system includes a photovoltaic thermal module, an air-water extraction module, a mass transfer drive module, and an electrolysis hydrogen production module.

[0031] The photovoltaic thermal module includes a solar panel 11 and a thermally conductive layer 13, with one side of the thermally conductive layer 13 in contact with the solar panel 11.

[0032] The air-to-water module includes a moisture-absorbing cloth 21 soaked in a hygroscopic salt solution. The moisture-absorbing cloth 21 is divided into a moisture-absorbing unit and an evaporation unit. The other side of the heat-conducting layer 13 is in contact with the evaporation unit. A hydrophobic and breathable membrane 22 is disposed below the moisture-absorbing cloth 21. Figure 1 In the illustrated embodiment, the main body of the air-to-water module is a flexible porous cotton cloth impregnated with lithium chloride solution. This absorbent cloth 21 is divided into a high-temperature section 211 and a low-temperature section 212. The low-temperature section 212 is exposed to ambient air and has a double-sided open structure, used to absorb water vapor from the air at night. The high-temperature section 211 is attached to the back of the solar panel 11 below the heat-conducting layer 13, used to receive solar heat during the day to release the absorbed moisture as water vapor. A hydrophobic and breathable membrane 22 is laid beneath the absorbent cloth 21, with an air gap 23 between the hydrophobic and breathable membrane 22 and the high-temperature section 211 of the absorbent cloth 21. The height of the air gap 23 is 15 mm. The hydrophobic and breathable membrane 22 has a pore size of 0.5 μm, a porosity of 75%, and a thickness of 120 μm, used to prevent liquid water splashing and allow only water vapor to pass through.

[0033] The mass transfer drive module includes a first solution tank 31 and a second solution tank 32 with a height difference. The height difference between the first solution tank 31 and the second solution tank 32 can be 1~5cm. The directional transport of moisture within the absorbent cloth 21 is a key link connecting the moisture absorption and desorption processes. Relying solely on a single concentration gradient for drive can easily lead to local concentration polarization and mass transfer interruption. By leveraging the synergistic effect of the height difference potential energy and capillary permeability, a continuous and stable pressure gradient can be established, ensuring continuous solution replenishment under high evaporation conditions and preventing localized drying and failure of the material.

[0034] The electrolytic hydrogen production module includes an alkaline electrolyzer, which contains an alkaline electrolyte 41, an anode 42, a cathode 44, and an alkaline electrolytic membrane 43. A hydrophobic and breathable membrane 22 is located between the evaporation unit and the alkaline electrolyte 41, and the two ends of the moisture-absorbing cloth 21 are in contact with the liquid surfaces inside the first solution tank 31 and the second solution tank 32, respectively.

[0035] In such Figure 1In the illustrated embodiment, the alkaline electrolytic cell contains a 30% (w / w) potassium hydroxide solution. The anode 42 is located at the top, and the cathode 44 is located at the bottom. An alkaline electrolytic membrane 43 is disposed between the anode 42 and the cathode 44, allowing only hydroxide ions to pass through. An air outlet is provided at the top of the electrolytic cell to discharge oxygen generated by the anode 42 and any air that may have mixed in. A separate hydrogen outlet is provided on the cathode 44 side to collect the hydrogen generated by the cathode 44.

[0036] During system operation, at night, the desiccant unit spontaneously adsorbs water vapor from the air, and under the influence of altitude difference and capillary force, the moisture is directionally transported to the evaporation unit. During the day, the photovoltaic thermal module can simultaneously provide electrical and thermal energy. The evaporation unit releases water vapor upon heating, and the water vapor directly passes through the hydrophobic and breathable membrane 22, is absorbed by the alkaline electrolyte 41, and completes electrolysis. The entire process requires no auxiliary components such as condensation, water storage, or water pumps. The system spontaneously adjusts the vapor partial pressure difference by dynamically changing the concentration of the desiccant salt solution and the alkaline electrolyte 41, automatically matching the desiccant absorption rate and the electrolysis consumption rate, achieving self-balancing operation without external control.

[0037] In some embodiments, a photoelectric conversion region 12 is arranged on the surface of the solar panel 11, and a thermally conductive layer 13 is fixedly attached to the back of the solar panel 11. This arrangement enables the full-spectrum cascade utilization of solar energy, where high-energy photons generate electricity through the photovoltaic effect, and low-energy waste heat photons are converted into heat energy and directionally supplied to the evaporation unit, avoiding the drawbacks of traditional solar energy utilization being singular and waste heat being wasted.

[0038] In some embodiments, the output terminal of the photovoltaic thermal module is electrically connected to the alkaline electrolytic cell. In such cases... Figure 1 In the illustrated embodiment, the output terminal of the photovoltaic thermal module and the alkaline electrolyzer are electrically connected via wire 14. This connection method allows the system to directly utilize solar power to drive the electrolysis process without requiring external power grid supply, making it suitable for remote areas far from the grid.

[0039] In some embodiments, the absorbent cloth 21 has a continuous capillary transport channel inside, which connects the moisture absorption unit and the evaporation unit. The absorbent cloth 21 can be cotton, non-woven fabric, or fiber fabric, with a porosity of 30% to 80%. The moisture absorption unit can adopt a double-sided exposed structure to increase the gas-liquid contact area and enhance static moisture absorption capacity. The capillary transport channel can ensure stable moisture transport, avoid local drying, and ensure continuous and stable moisture absorption and desorption processes.

[0040] In some embodiments, an air gap 23 is provided between the hydrophobic and breathable membrane 22 and the evaporation unit. The height of the air gap 23 can be 10~20mm. The pore size of the hydrophobic and breathable membrane 22 can be 0.1~1μm. The porosity can be 60%~85%, and the thickness can be 50~200μm. The air gap 23 can reduce the mass transfer resistance of water vapor, while blocking the contact between liquid water and electrolyte, maintaining a stable solution concentration. The hydrophobic and breathable membrane 22 adopts a one-way breathable barrier design, preventing the liquid medium from permeating and mixing, and only allowing gaseous water molecules to pass through in a directional manner.

[0041] In some embodiments, a liquid guide pipe or circulation device is provided between the first solution tank 31 and the second solution tank 32 to connect the hygroscopic salt solutions inside the two solution tanks. This structure can maintain a dynamic balance of solution concentration and liquid level in the two solution tanks, reduce the mass transfer attenuation caused by excessive local concentration differences, and ensure the stability of long-term passive mass transfer driving force.

[0042] In some embodiments, the anode 42 is located at the upper part of the alkaline electrolytic cell, the cathode 44 is located at the lower part of the alkaline electrolytic cell, and the alkaline electrolytic diaphragm 43 is disposed between the anode 42 and the cathode 44. This staggered arrangement, with the anode 42 above and the cathode 44 below, allows the oxygen generated at the anode 42 to escape upwards rapidly, while the hydrogen gas at the cathode 44 accumulates downwards, reducing the overpotential rise caused by bubbles covering the electrode surface. This arrangement facilitates rapid gas detachment from the electrode surface, reducing electrolytic overpotential, while also preventing large-scale mixing of hydrogen and oxygen gases, thus improving operational safety.

[0043] In some embodiments, the alkaline electrolytic membrane 43 is a polyphenylene sulfide membrane, a polyether ether ketone membrane, or a composite membrane. The alkali-resistant polymer membrane material possesses excellent resistance to alkali corrosion, is suitable for long-term immersion in the alkaline electrolyte 41, effectively blocks the cross-contamination of hydrogen and oxygen gases, and only allows ion conduction in a directional manner.

[0044] In some embodiments, the hygroscopic salt solution is a lithium chloride solution, and the alkaline electrolyte 41 is a potassium hydroxide solution. The combination of the two salt solutions forms a stable and controllable vapor pressure difference, which can maintain efficient gas-phase mass transfer even in low humidity environments and inhibit the carbonation and deterioration of the electrolyte. The combination of lithium chloride solution and potassium hydroxide solution can form a significant vapor pressure difference, which is much higher than the conventional gas-water saturation pressure difference, thus enhancing the working capability in low humidity environments.

[0045] In some embodiments, the photovoltaic thermal module, the air-water intake module, the mass transfer drive module, and the electrolysis hydrogen production module are stacked sequentially to form an integrated hydrogen production unit. This integrated structure significantly reduces system size, facilitates mass production, flexible deployment, and parallel expansion, and is suitable for distributed hydrogen production scenarios.

[0046] To fully demonstrate the technical advantages of this invention, comparative examples are provided in conjunction with existing similar technical solutions.

[0047] Comparative Example 1 is a water electrolysis hydrogen production device based on direct exposure to hygroscopic potassium hydroxide solution. It places a 30% (w / w) potassium hydroxide solution in an open container, utilizing the hygroscopic property of the potassium hydroxide solution to capture moisture from the ambient air, and simultaneously uses this solution as the electrolyte for alkaline water electrolysis to produce hydrogen. This comparative example has the following drawbacks: (1) Insufficient moisture absorption driving force. The difference between the partial pressure of water vapor on the surface of potassium hydroxide solution and the partial pressure of water vapor in the ambient air is small. When the relative humidity of the environment is below 50%, this vapor pressure difference is usually less than 0.5 kPa, resulting in an extremely low moisture absorption rate, which cannot provide enough water for the electrolysis process. In arid areas with a relative humidity of around 30%, this ratio is almost ineffective in collecting water.

[0048] (2) Poor electrolyte stability. When potassium hydroxide solution is directly exposed to air, it continuously absorbs carbon dioxide from the air to form potassium carbonate, which leads to a decrease in electrolyte conductivity, an increase in viscosity, and electrode passivation. Experiments show that under open conditions, the carbonate content of potassium hydroxide solution can rise to more than 5% within 72 hours, and the electrolysis efficiency decreases by more than 30%.

[0049] (3) It cannot achieve self-driving operation. Since the moisture absorption rate and the electrolysis rate cannot be automatically matched, an additional humidity sensor, water pump and control system are required to adjust the solution concentration and water supply, which increases the system energy consumption and failure risk.

[0050] Therefore, Comparative Example 1 cannot achieve efficient and stable self-driven hydrogen production in arid, off-grid environments.

[0051] Comparative Example 2 is a conventional adsorption-condensation coupled electrolysis hydrogen production device. It uses silica gel or metal-organic framework materials as adsorbents, adsorbing water vapor from the air at night and desorbing it during the day using solar energy. The water vapor is condensed into liquid water in a condenser, collected, and supplied to a PEM electrolyzer for hydrogen production. This comparative example has the following drawbacks: (1) Poor environmental adaptability. In low-temperature and low-humidity environments with temperatures below 10℃ and relative humidity below 40%, the equilibrium adsorption capacity of solid adsorbent materials decreases significantly. At the same time, the temperature required for desorption is usually above 80℃, while the solar thermal temperature in arid regions is generally below 60℃, resulting in incomplete desorption and a sharp drop in water collection efficiency. In high-temperature environments with temperatures above 35℃, the condenser has difficulty cooling water vapor below the dew point, and the condensation efficiency drops sharply, even making it impossible to collect liquid water. For example, in a desert summer with temperatures of 40℃, even if a large amount of water vapor is desorbed, it cannot be effectively condensed.

[0052] (2) Low energy utilization. The condensation process of water vapor releases approximately 2.4 MJ / kg of latent heat, which is directly lost to the environment and not utilized by the system. Taking a daily water production of 100 mL as an example, the latent heat loss from condensation alone reaches 240 kJ, accounting for 20% to 30% of the solar energy input. The overall solar-hydrogen energy conversion efficiency is usually less than 2%, significantly lower than that of this invention.

[0053] (3) The system has a complex structure and many moving parts. This comparative model needs to be equipped with openable and closable covers, condenser fins, water collection tanks, water pipelines, water pumps and valves, etc. It is large in size and weight, and there are risks of failure such as sealing failure and jamming of moving parts, making it difficult to operate for a long time in remote and maintenance-free conditions.

[0054] (4) Poor economic efficiency. PEM electrolyzers require precious metal catalysts such as platinum and iridium, as well as perfluorosulfonic acid membranes, and their manufacturing cost is approximately 3 to 5 times that of alkaline electrolyzers of equivalent power. In addition, the condensed liquid water may dissolve carbon dioxide and other impurities in the air, requiring additional ion exchange resin purification devices, further increasing system complexity and cost. This comparative example also requires external power to drive auxiliary equipment such as water pumps and valves, making fully passive operation impossible.

[0055] To fully verify the actual operating performance of the present invention, a prototype was built to conduct a multi-condition control experiment. The experimental environment covered normal temperature and natural light, and different relative humidity conditions. The water intake rate, hydrogen production efficiency, energy utilization rate and long-term operating stability were continuously monitored.

[0056] Under normal environmental humidity of 55%±5%, the system maintains a stable average water intake rate during the day, which can fully meet the water consumption requirements of continuous electrolysis in an alkaline electrolyzer. In a drought simulation environment with low humidity of 30%±3%, the system can still maintain continuous water intake and stable hydrogen production by relying on the enhanced mass transfer effect of the vapor pressure difference of the dual salt solution, without any water shortage or shutdown.

[0057] Tests showed that the overall solar energy utilization efficiency of the entire device was significantly better than that of traditional adsorption-condensation hydrogen production equipment. Eliminating the condensation stage significantly reduced system heat loss and improved overall energy utilization. Long-term continuous operation tests demonstrated that the closed structure effectively protected the electrolyte. After several days of uninterrupted operation, the potassium hydroxide solution showed no obvious carbonization or deterioration, and the electrode surfaces exhibited no severe passivation or corrosion, demonstrating excellent overall operational stability.

[0058] Compared to Comparative Example 1, this invention employs a dual-salt solution vapor pressure difference composite driving mode, significantly enhancing the hygroscopic mass transfer power and greatly improving adaptability to low-humidity and arid environments. Combined with a fully enclosed isolation structure, it isolates acidic gases and impurities from the source, providing long-term protection for the electrolyte and electrode components. It achieves adaptive balanced operation without complex electronic control components, significantly reducing equipment failure rate and maintenance costs. Compared to Comparative Example 2, this invention completely eliminates intermediate steps such as condensation liquefaction and freshwater storage and transportation, adopting a direct gas-phase mass transfer mode to achieve in-situ heat recovery and utilization, eliminating latent heat loss during condensation and significantly improving energy utilization efficiency. With no easily damaged mechanical parts such as condensers and circulating water pumps, the overall structure is simple and reliable, with a wider range of operating conditions adaptability. Leveraging the low-cost advantage of the alkaline electrolysis system, its overall industrial application value is higher.

[0059] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A self-driven solar-powered air-water extraction coupled hydrogen production system, characterized in that: The system includes a photovoltaic-thermal module, an air-water extraction module, a mass transfer-driven module, and an electrolytic hydrogen production module. The photovoltaic-thermal module comprises a solar panel and a thermally conductive layer, with one side of the thermally conductive layer in contact with the solar panel. The air-water extraction module includes a moisture-absorbing cloth soaked in a hygroscopic salt solution, the cloth being divided into a moisture-absorbing unit and an evaporation unit, with the other side of the thermally conductive layer in contact with the evaporation unit. A hydrophobic and breathable membrane is disposed below the moisture-absorbing cloth. The mass transfer-driven module includes a first solution tank and a second solution tank with a height difference. The electrolytic hydrogen production module includes an alkaline electrolytic cell, which contains an alkaline electrolyte, an anode, a cathode, and an alkaline electrolytic membrane. The hydrophobic and breathable membrane is located between the evaporation unit and the alkaline electrolyte, and the two ends of the absorbent cloth are in contact with the liquid surfaces inside the first solution tank and the second solution tank, respectively.

2. The self-driven solar-powered air-water extraction coupled hydrogen production system according to claim 1, characterized in that: The solar panel has a photoelectric conversion area on its surface, and the thermal conductive layer is fixedly attached to the back of the solar panel.

3. The self-driven solar-powered air-water extraction coupled hydrogen production system according to claim 2, characterized in that: The output terminal of the photovoltaic thermal module is electrically connected to the alkaline electrolytic cell.

4. The self-driven solar-powered air-water extraction coupled hydrogen production system according to claim 1, characterized in that: The absorbent cloth has a continuous capillary transmission channel inside, which connects the absorbent unit and the evaporation unit.

5. The self-driven solar-powered air-water extraction coupled hydrogen production system according to claim 1, characterized in that: An air gap is provided between the hydrophobic and breathable membrane and the evaporation unit.

6. The self-driven solar-powered air-water extraction coupled hydrogen production system according to claim 1, characterized in that: A liquid guide pipe or circulation device is provided between the first solution tank and the second solution tank to connect the hygroscopic salt solution inside the two solution tanks.

7. The self-driven solar-powered air-water extraction coupled hydrogen production system according to claim 1, characterized in that: The anode is located at the top of the alkaline electrolytic cell, the cathode is located at the bottom of the alkaline electrolytic cell, and the alkaline electrolytic diaphragm is disposed between the anode and the cathode.

8. The self-driven solar-powered air-water extraction coupled hydrogen production system according to claim 1, characterized in that: The alkaline electrolytic membrane is a polyphenylene sulfide membrane, a polyether ether ketone membrane, or a composite membrane.

9. The self-driven solar-powered air-water extraction coupled hydrogen production system according to claim 1, characterized in that: The hygroscopic salt solution is a lithium chloride solution, and the alkaline electrolyte is a potassium hydroxide solution.

10. The self-driven solar-powered air-water extraction coupled hydrogen production system according to claim 1, characterized in that: The photovoltaic and photothermal module, air-water intake module, mass transfer drive module, and electrolysis hydrogen production module are arranged in sequence to form an integrated hydrogen production unit.

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