Extract water from the air and redistribute it to plants
A new type of soil created by engineers from the university of texas in Austin can extract water from the air and distribute it to plants, which could expand the map of the world's arable land to previously inhospitable places and reduce water use in agriculture in an era of increasing drought.
Enable autonomous agriculture
As published in ACS Materials Letters, the team's atmospheric irrigation system uses super-absorbent gels to capture water from the air. When the soil is heated to a certain temperature, the gels release the water, making it available to plants. As the soil distributes water, some of it returns to the air, which increases humidity and makes it easier to continue the harvest cycle.
Enabling self-sustaining agriculture in areas where it is difficult to establish irrigation and energy systems is essential to freeing crops from the complex water supply chain, as resources are increasingly scarce. rare, said Guihua Yu, associate professor of materials science in Walker's mechanical engineering department.
Each gram of soil can extract about 3 to 4 grams of water. Depending on the crop, about 0,1 to 1 kilogram of soil can provide enough water to irrigate about one square meter of farmland.
Frost in the soil extracts water from the air during the cooler, wetter parts of the night. Solar heat during the day activates gels containing water to release their contents into the soil.
Why a self-watering soil?
The team conducted experiments on the roof of the Cockrell School's Engineering Education Center building at UT Austin to test the soil. They found that the hydrogel soil was able to hold water better than sandy soils dry areas, and needed much less water to grow plants.
During a four-week experiment, the team found that their soil retained about 40% of the amount of water it started with. In contrast, the sandy soil had only 20% of its water left after just a week.
In another experiment, the team planted radishes in both types of soil. The radishes in the hydrogel soil all survived a period of 14 days without any irrigation beyond a first turn to ensure that the plants took root there. The radishes in the sandy soil were irrigated several times during the first four days of the experiment. None of the radishes in the sandy soil survived more than two days after the initial irrigation period.
“Most soils are good enough to support plant growth”, said Fei Zhao, a postdoctoral fellow in the Yu Research Group who led the study with Xingyi Zhou and Panpan Zhang. “Water is the main limitation, which is why we wanted to develop a soil that can collect water from the ambient air”.
A hydraulic gel capable of collecting water
Soil that collects water is the first major application of the technology that Yu's group has been working on for more than two years. Last year, the team developed the ability to use hybrid gel-polymer materials that work like “super sponges,” extracting large amounts of water from the surrounding air, cleaning it and quickly releasing it. thanks to solar energy.
The research team combined hydrogels that strongly absorb water and can release water upon heating. This unique combination has been successfully proven to work in wet and dry weather conditions and is essential to enable the production of clean and safe drinking water from the air.
Solar-powered moisture harvester collects and purifies water from the air
This breakthrough could be used in disaster situations, to stem water crises or in poverty stricken regions and developing countries. Access to drinking water remains one of the great challenges facing humanity. This breakthrough, made by engineers at the University of Austin in Texas, could offer a new solution thanks to this solar technology that absorbs moisture from the air and releases it in the form of clean, usable water.
With around 50000 cubic kilometers of water in the atmosphere, this new system could tap into those reserves and potentially lead to small, portable and inexpensive filtration systems.
However, the team's new innovation goes one step further in this work by using the water that already exists in the atmosphere. For the two hydrogel-based technologies, Yu and his research team developed a way to combine materials that have both hygroscopic (water-absorbing) qualities and thermosensitive hydrophilicity (the ability to release water by simple heating).
The technology could replace basic components of existing solar-powered water purification systems or other moisture-absorbing technologies.
Researchers are considering several other applications of this technology. It could potentially cool solar panels and data centers. As a result, it could expand access to drinking water, either through individual systems for households, or through larger systems for large groups such as workers or soldiers.