However, this device can draw out literally liters of water from the air in conditions that have humidity levels as low as 20%, common is desert environments.
"We've built a device that captures water from air", Evelyn Wang, an associate engineering professor at MIT, told Digital Trends. After all, dehumidifiers make sure that a room or home does not easily grow mold by sucking out the moisture from the air, and at the end of the day, you will have to pour all of the water away somewhere else.
Though researchers at Berkeley and MIT have developed a way to extract clean water from thin air, it will take more research and development to bring the prodct to an cheap enough price that it can be economically distributed to countries around the world and aras where clean water is in short supply.
The MIT team then took dust-sized crystals of this MOF and compressed them between a solar absorber and a condenser plate, and placed the whole thing inside a chamber that was exposed to the outside air. They have used Zirconium and adipic acid for designing this MOF. Sunlight heats the MOF and drives the water towards the condenser. While the material has a high affinity for water molecules, it easily releases the concentrated water with a slight change in temperature. And in 2014, Yaghi and his team synthesized MOF-801 having strong affinity for water molecules even under low-humidity conditions.
As they report in the journal Science, Wang and her colleagues tested the prototype of their MOF-based device on the roof of a building at MIT, and it worked great. Other solutions have also been approached, but they typically require significant humidity in the air to work - this one works with nearly no humidity. The key is a special type of compound known as a metal organic framework, or MOF, a crystalline material involving metal ions linked with organic molecules.
FreshWater consists of a larger tank with much higher energy requirements, able to produce from 9 to 28 liters of water per day with a 450W consumption rate. MOFs represent materials developed via stitching, putting together inorganic and organic metallic units, transforming them into porous frameworks with broad surface areas. Thus, this material makes it possible to conserve massive amounts of gasses in some incredibly small receptacle.
MOFs have been used for many different applications in the past, including gas storage, dehumidification and the capture of carbon dioxide emissions. Everyone having their own device at home powered by solar energy to meet daily water requirements.
Researchers behind the project have called it the realization of a "longstanding dream", even if Yaghi himself suggests that there is a lot of potential for improving the concept. "Water goes in at large quantities but at the same time the material doesn't hold on to it too tightly", Yaghi says. Many firms are using these MOF to produce water. If the solar cube can harvest water in the Sahara, it means that it can work in other deserts as well.
PALCA: In a prototype Wang has built, the energy you need to heat the system comes from sunlight - no external power supply needed.
"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".