Imagine a world where every single one of us has a device that pulls all the water the households needs out of the air, by using only the power of the Sun. This actually may be just around the corner: recently, scientists made a water harvester that is using ambient sunlight in order to pull liters of water (out of the air) each day.
This solar-powered harvester was produced at the Massachusetts Institute of Technology, as it was reported in the journal Science.
Omar Yaghi explained: “This is a major breakthrough in the long-standing challenge of harvesting water from the air at low humidity. There is no other way to do that right now, except by using extra energy. Your electric dehumidifier at home ‘produces’ very expensive water.”
The prototype was actually able to pull 2.8 liters of water even under conditions of 20-30 percent humidity in a period of half a day.
“One vision for the future is to have water off-grid, where you have a device at home running on ambient solar for delivering water that satisfies the needs of a household. To me, that will be made possible because of this experiment. I call it personalized water.” Yaghi explained.
This man actually invented metal-organic frameworks more than 20 years when he combined metals like aluminium or magnesium with organic molecules on a some kind of tinker-toy arrangement in order to create rigid, porous structures that appear to be ideal for storing liquids and gases.
Since then, a lot of MOFs were made, but the most crucial one that helped this latest research was synthesized by UC Berkeley team. Yaghi suggested To Evelyn Wang, who is a mechanical engineer at MIT that they should join forces so they can turn the MOF into an amazing system that collects water.
Of course, Wang couldn’t resist this idea. He later explained: “This work offers a new way to harvest water from air that does not require high relative humidity conditions and is much more energy efficient than other existing technologies.”
Wang also said the this concept actually leaves much room for improvement and even if the current MOF is able to absorb only 20% of its weight in water, in the future they will be working on materials that will be able to absorb 40% or even more.
“It’s not just that we made a passive device that sits there collecting water; we have now laid both the experimental and theoretical foundations so that we can screen other MOFs, thousands of which could be made, to find even better materials,” he explained. “There is a lot of potential for scaling up the amount of water that is being harvested. It is just a matter of further engineering now.”
“To have water running all the time, you could design a system that absorbs the humidity during the night and evolves it during the day,” he said. “Or design the solar collector to allow for this at a much faster rate, where more air is pushed in. We wanted to demonstrate that if you are cut off somewhere in the desert, you could survive because of this device. A person needs about a Coke can of water per day. That is something one could collect in less than an hour with this system.