Device produces drinkable water from desert air
Researcher have discovered a way to produce water in the desert from thin air.Scientists at the Massachusetts Institute of Technology (MIT) have developed technology that could save lives in harsh desert climates. The technology allows users to transform moisture in the air into water.
A new report by the researchers, published in Nature Communications, explains how this can be useful around the world since the air in every desert holds at least some moisture. The new research could help people survive the most arid climates on earth, the MIT team said.
The technology was first proposed in a paper published in Science last year, and it drew both optimistic attention and skepticism from the scientific community.Prof. Evelyn Wang, who worked on the original paper as well as the recently published study, said: “It got a lot of hype and some criticism.“All of the questions that were raised from last time were explicitly demonstrated in this paper. We’ve validated those points.”
The new product was tested in Tempe, Arizona, and the testing confirmed that it has the potential to help people stay hydrated in deserts.The analysis said: “The system, based on relatively new high-surface-area materials called metal-organic frameworks (MOFs), can extract potable water from even the driest of desert air with relative humidities as low as 10 percent.
“Current methods for extracting water from air require much higher levels – 100 percent humidity for fog-harvesting methods and above 50 percent for dew-harvesting refrigeration-based systems, which also require large amounts of energy for cooling.“So the new system could potentially fill an unmet need for water even in the world’s driest regions.”How much water can be produced from desert air? MIT researchers have developed a way to produce heat in the dessert. Their technology could be used to provide hydration in dangerously dry areas around the world.
The device is powered by sunlight only, and the researchers said it could eventually be used to provide more than one-fourth of a liter of water per kilogram of metal-organic framework each day.This output could be much higher if a more efficient material were to be used, the report stated.The technology operates on a night-and-day cycle using sunlight.
But, researcher Dr. Hyunho Kim said, “continuous operation is also possible by utilizing abundant low-grade heat sources such as biomass and waste heat.”Professor Wang said the device’s placement during testing – on the rooftop of an Arizona State University building – allowed researchers to observe the technology “in a place that’s representative of arid areas, and [it] showed that we can actually harvest the water even in subzero dewpoints.”
Additionally, the system is more low maintenance than competing methods.Researcher Sameer Rao said: “This has no moving parts. It can be operated in a completely passive manner in places with low humidity but large amounts of sunlight.“Now we have demonstrated that this is indeed possible.”
Professor Wang noted that the next step is to boost the technology’s efficiency.“We hope to have a system that’s able to produce liters of water. We want to see water pouring out,” she said.“These small, initial test systems were only designed to produce a few milliliters to prove the concept worked in real-world conditions, [but] the idea would be to produce units sufficient to supply water for individual households,” the study said.No impurities were detected in the water created during the testing.