News

Solar-powered moisture harvester collects and cleans water from air

Fei Zhao (L), co author of the study, and Guihua Yu (R) of Yu Research Labs at UT Austin examining a sample of their newly-developed hydrogel.

Credit: Cockrell School of Engineering, The University of Texas at Austin

Fei Zhao (L), co author of the study, and Guihua Yu (R) of Yu Research Labs at UT Austin examining a sample of their newly-developed hydrogel.

Credit: Cockrell School of Engineering, The University of Texas at Austin

Close

Access to clean water remains one of the biggest challenges facing humankind. A breakthrough by engineers at The University of Texas at Austin may offer a new solution through solar-powered technology that absorbs moisture from the air and returns it as clean, usable water.

advertisement

The breakthrough, described in a recent issue of the journal Advanced Materials, could be used in disaster situations, water crises or poverty-stricken areas and developing countries. The technology relies on hydrogels, gel-polymer hybrid materials designed to be "super sponges" that can retain large amounts of water.

A research team led by Guihua Yu in UT Austin s Cockrell School of Engineering combined hydrogels that are both highly water absorbent and can release water upon heating. This unique combination has been successfully proved to work in humid and dry weather conditions and is crucial to enabling the production of clean, safe drinking water from the air.

With an estimated 50,000 cubic kilometers of water contained in the atmosphere, this new system could tap into those reserves and potentially lead to small, inexpensive and portable filtration systems.

"We have developed a completely passive system where all you need to do is leave the hydrogel outside and it will collect water," said Fei Zhao, a postdoctoral researcher on Yu s team and co-author of the study. "The collected water will remain stored in the hydrogel until you expose it to sunlight. After about five minutes under natural sunlight, the water releases."

This technology builds upon a 2018 breakthrough made by Yu and Zhao in which they developed a solar-powered water purification innovation using hydrogels that cleans water from any source using only solar energy. The team s new innovation takes that work a step further by using the water that already exists in the atmosphere. For both hydrogel-based technologies, Yu and his research team developed a way to combine materials that possess both hygroscopic (water-absorbing) qualities and thermal-responsive hydrophilicity (the ability to release water upon simple heating).

"The new material is designed to both harvest moisture from the air and produce clean water under sunlight, avoiding intensive energy consumption," said Yu, an associate professor of materials science and mechanical engineering.

Harvesting water from moisture is not exactly a new concept. Most refrigerators keep things cool through a vapor condensation process. However, the common fridge requires lots of energy to perform that action. The UT team s technology requires only solar power, is compact and can still produce enough water to meet the daily needs of an average household. Prototype tests showed daily water production of up to 50 liters per kilogram of hydrogel.

Representing a novel strategy to improve upon atmospheric water harvesting techniques being used today, the technology could also replace core components in existing solar-powered water purification systems or other moisture-absorbing technologies.

Yu and his team have filed a patent, and Yu is working with UT s Office of Technology Commercialization on the licensing and commercialization of this innovative class of hydrogels. The research was funded by the Alfred P. Sloan Foundation, the Camille & Henry Dreyfus Foundation and the National Science Foundation.

advertisement

Materials provided by . Note: Content may be edited for style and length.

University of Texas at Austin. "Solar-powered moisture harvester collects and cleans water from air." ScienceDaily. ScienceDaily, 14 March 2019. .

University of Texas at Austin. "Solar-powered moisture harvester collects and cleans water from air." ScienceDaily. www.sciencedaily.com/releases/2019/03/190314123149.htm (accessed March 14, 2019).
Read more on sciencedaily.com
News Topics :
RELATED STORIES :
Technology
High humidity causes discomfort and makes hot days feel more unbearable. A team of researchers from the National University of Singapore NUS has invented a novel gel like material that not...
Technology
Homes with solar panels do not require on site storage to reap the biggest economic and environmental benefits of solar energy, according to research from the Cockrell School of Engineering at...
Technology
Optical microscope images of crystals of the newest, aluminum based metal organic framework, MOF 303, which captures twice as much water as the earlier MOF used in the water harvester Credit Omar Yaghi...
Technology
Hydrogels are soft, wet, biocompatible, and can form more friendly interfaces with human organs, says Xuanhe Zhao, associate professor of mechanical engineering and civil and environmental engineering at MIT. Credit...
Technology
A team of engineers led by 94 year old John Goodenough, professor in the Cockrell School of Engineering at The University of Texas at Austin and co inventor of the lithium ion battery, has...