Opportunity
The global challenges of water scarcity and food insecurity are intensifying due to population growth, overconsumption, and climate change. Billions of people face dire water shortages, which severely limit agricultural regions and contribute to widespread malnutrition. Traditional agriculture is heavily dependent on freshwater irrigation and chemical fertilizers. However, freshwater resources are increasingly depleted, and the misuse of chemical fertilizers imposes a significant burden on the environment and human health, causing pollution and ecosystem damage. There is a critical need for sustainable, off-grid solutions that can provide essential water and nutrients, particularly for arid and barren areas, to enhance food production without exacerbating environmental problems or relying on conventional energy-intensive infrastructure.
Technology
This patent discloses an integrated Water and Nutrient Capture System (WNCS) that directly harvests water and produces nitrogen-based fertilizers from the air. The core innovation is a synergistic combination of three main components: a biomimetic fog harvester, an electricity generator, and a discharge reactor. The fog harvester features a three-dimensional, modular design with units shaped as hollow cylinders covered in spikes. The surface of these spikes is engineered with a biphilic patterned structure—typically a hydrophilic pattern (e.g., circles or triangles) on a hydrophobic substrate. This design, inspired by cacti and beetles, enhances internal air vortices to trap fog droplets and optimizes droplet coalescence and detachment, achieving a high water collection rate exceeding 6 kg/m²/h and an efficiency of about 35%. The collected water then flows into a spark-type droplet-based electric generator (SDEG), such as a Kelvin water dropper. This device harnesses the gravitational potential energy and triboelectric effect of the falling droplets to generate high-voltage electricity (up to ~8 kV) without external power. This electricity powers a discharge reactor where high-voltage electric sparks facilitate nitrogen fixation. The sparks ionize air, converting atmospheric nitrogen and oxygen into nitrogen oxides (NO/NO₂), which dissolve in water to form nitrate-rich fertilizer for plants. The entire system operates as a self-sustaining, closed-loop process that converts atmospheric fog and air into vital agricultural resources.
Advantages
- Provides a sustainable, off-grid source of both water and nitrogen fertilizer directly from the atmosphere.
- Eliminates reliance on traditional, energy-intensive fertilizer production (e.g., Haber-Bosch process) and reduces dependency on freshwater irrigation.
- The biomimetic fog harvester design achieves superior water collection efficiency (over 35%) and fog harvesting capability compared to conventional mesh or harp structures.
- Integrates energy generation (from water flow) and consumption (for nitrogen fixation) within a single, self-powered system.
- Modular design allows for scalable deployment, from small units to large arrays, adaptable to various environments and needs.
- Promotes plant growth and enhances nutritional content (e.g., increased chlorophyll, protein, vitamins) in crops like peas and wheat.
- Can also be used to apply an electric field to seeds, significantly improving germination rates.
Applications
- Agriculture and Horticulture: Providing irrigation water and organic nitrate fertilizer for crop cultivation, especially in arid, semi-arid, or remote regions.
- Afforestation and Land Reclamation: Supporting plant growth in barren or nutrient-deficient soils for ecosystem restoration.
- Water Security: Harvesting atmospheric water for drinking or irrigation in water-scarce communities.
- Sustainable Fertilizer Production: On-site generation of nitrogenous nutrients, reducing the carbon footprint and pollution associated with chemical fertilizer manufacturing and transport.
- Controlled Environment Agriculture: Integrating into greenhouse or vertical farming systems for resource-efficient food production.
