Dwindling reservoirs, prolonged droughts, and increasing demand create a concerning outlook for US water resources. However, a promising area of materials science research may offer a new approach to sourcing this essential resource: pulling water directly from the atmosphere through atmospheric water harvesting (AWH).
Researchers have developed highly porous materials called metal-organic frameworks (MOFs) and covalent organic frameworks (COFs). These crystalline structures possess incredibly large internal surface areas, allowing them to efficiently capture water vapor from the air, even in very dry conditions. Imagine a teaspoon of MOF powder having the surface area of a football field—that gives you a sense of their capacity.
These materials work by combining this vast internal surface area with chemical properties that attract water molecules. Think of it like a sponge specifically designed to soak up water from the air. This process, called atmospheric water harvesting (AWH), requires minimal energy input, making it a potentially sustainable solution for water scarcity.
One company, Atoco, has developed AWH systems that can extract water even when humidity levels are below 20%, a threshold that challenges traditional water harvesting methods. Their approach offers a potential alternative or perhaps a piece of the puzzle to relying solely on increasingly stressed natural water sources.
Atoco recently demonstrated an off-grid, solar-powered water generation unit in Nevada, a state grappling with severe water shortages. Their research suggests that a medium-sized AWH station could generate a significant amount of water daily, offering a decentralized and self-sustaining solution. This is particularly important in regions like Nevada that rely heavily on the overallocated Colorado River system.
The potential impact of this technology extends far beyond the Western US. Scalable solutions like AWH could play a crucial role in ensuring water security worldwide. TWR continues to track innovative and creative solutions such as this.
