Ultra-black wool turns saltwater into drinking water using sunlight, costs under $1 per sheet

Researchers have developed an ultra-black wool that absorbs sunlight efficiently to evaporate seawater, producing fresh water. The material is biodegradable and costs less than one dollar for a sheet the size of paper, making it a promising low-cost option for vulnerable communities lacking clean water access. The technology leverages solar thermal conversion, similar to other passive desalination approaches, but with a natural and disposable substrate. This development matters because it addresses both water scarcity and environmental footprint. Unlike conventional desalination membranes that require energy and maintenance, this wool-based approach is simple and could be deployed in off-grid settings. While still early stage, the low cost and material availability suggest potential for scalable production. The next step is field testing in real conditions to verify durability and performance outside the lab.