Scientists Create Water-Harvesting Technology That Uses Kitchen Scraps and Seashells – Decrypt

Researchers at the University of Texas at Austin have figured out how to turn everyday throwaways into a technology that pulls clean water straight from the atmosphere.

The team used different organic materials to develop “molecularly functionalized biomass hydrogels” that extract drinkable water from air using only mild heat, producing nearly four gallons daily per kilogram of material—about three times more than typical water-harvesting technologies.

“This opens up an entirely new way to think about sustainable water collection, marking a big step towards practical water harvesting systems for households and small community scale,” said Professor Guihua Yu, who led the research team.

The research is relevant today, considering nearly 4.4 billion people have restricted access to safe drinking water, according to recent studies. That’s nearly 50% of the entire human population.

Extracting water out of air is not really new, but what sets this approach apart is its use of natural materials that would otherwise end up in landfills—making it safer and more environmentally friendly too. The researchers successfully converted cellulose (found in plants), starch (from foods like corn and potatoes), and chitosan (from seashells) into high-performance water harvesters.

“At the end of the day, clean water access should be simple, sustainable, and scalable,” said Weixin Guan, another researcher involved in the study. “This material gives us a way to tap into nature’s most abundant resources and make water from air—anytime, anywhere.”

The technology works through a two-step process. First, researchers attach thermoresponsive groups to make the materials sensitive to temperature changes. Then, they add special molecules called “zwitterionic groups” to boost the biomass’ water absorption capacity.

The result is a hydrogel that works somewhat like the silica gel packets found in a normal dehumidifier, but with dramatically better performance and safer composition, using natural materials instead of synthetics.

During field tests, the system demonstrated to be successful—a single kilogram of material produced up to 14.19 liters of water daily. The team says similar technologies typically generate between 1 and 5 liters per kilogram each day.

Unlike conventional water harvesting systems that often rely on energy-hungry refrigeration to condense atmospheric moisture, these hydrogels need only mild heating to 60°C (140°F) to release their captured water—a temperature achievable with simple solar heating or waste heat from other processes.

This minimal energy requirement makes the technology particularly promising for off-grid communities and emergency situations where power might be unavailable.

Professor Yu’s team has been developing water-generating technologies for years, including systems adapted for extremely dry conditions and injectable water filtration systems. They’re now working on scaling production and designing practical devices for commercialization, including portable water harvesters, self-sustaining irrigation systems, and emergency drinking water devices.

Edited by Andrew Hayward