The scientists at the University of California, Berkley, have some good news for people living in arid regions. These scientists have successfully harvested water from the air with the help of a solar-powered system.
The test was conducted in Scottsdale, Arizona at a location in the Arizona desert. This desert area sees a relative humidity drop from a high of 40 percent at night to low of 8 percent during the day making it an ideal testing area.
The advantages of this solar-powered water harvester are many, especially in water-stressed regions, as it can extract drinkable water at very low humidity and at low cost every day and night. The harvester can be easily adjusted according to the humidity by adding more of the water absorber.
“It operates at ambient temperature with ambient sunlight, and with no additional energy input you can collect water in the desert. This laboratory-to-desert journey allowed us to really turn water harvesting from an interesting phenomenon into science,” said Omar Yaghi, the inventor of this harvesting technology.
Metal-organic framework (MOF), a highly porous material, is used to absorb water. It is made from a metal called Zirconium. Researchers at the university expect that they will be able to extract about 200 milliliters (about 7 ounces) of water per kilogram (2.2 pounds) of MOF, or 3 ounces of water per pound.
Given that Zirconium is expensive, the team has created another MOF that is aluminum-based. This MOF is 150 times cheaper and captures twice as much water than Zirconium based MOFs in laboratory tests. According to the results, it can produce more than 400 ml (3 cups) of water per day from a kilogram of MOF. That is the equivalent of half a 12-ounce soda can per pound per day.
This technology, if commercialized, can be extremely useful in states like Rajasthan in India which has tremendous solar potential but not enough water.
Image credit: UC Berkley