Scientists have developed devices that could pull our water from the desert areas, powered only by sunlight. They are hoping that a version of this technology could probably start the supply of purified drinking water in the dry and poor areas of the world.
These devices work on a novel kind of material which could extract a large volume of water into its various number of pores. According to a study published in the journal Science this Thursday, around a kilogramme of its material are capable of capturing litres of water each day when the humidity level is as low as 20 percent, which is typical of arid areas.
A report during the last year in Science Advances had found that nearly four billion residents, almost half in India as well as in China, face “severe water scarcity at least during one month of the year.” This means that water shortages have affected about two-thirds of the world’s growing population. These shortages—and conflicts are only expected to get more popular in large parts of the globe as the climatic changes accelerate.
A team at MIT has developed the technology working in Omar Yaghi’s laboratory at the University of California, Berkeley. These devices have components which promise a class of synthetic porous materials also known as metal-organic frameworks and are composed of organic molecules attached along with the metal atoms, which Yaghi developed. The size of the material and its chemical character have pores which can be customized for capturing some particular category of molecules and allows them to flow through. The material consists of a massive area of the surface, in order of a football field per gram, allowing it to connect with large quantities of particles.
“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,” said Yaghi. “To me, that will be made possible because of this experiment. I call it personalised water,” he said. The new system is composed of dust-sized MOF particles which are compressed between a solar absorber and a condenser plate, which is placed inside a chamber which is left open to the air.
As the atmospheric air gets diffused while passing through the porous MOF, , the water molecules that are by preference get attached to the interior surfaces. Sun rays that are entering by means of a window heats up the MOF and the bound water rushes to the condenser, which has the same temperature as is the temperature of the outside air. The vapor gets condensed in the form of liquid water and drips inside the collector from where clean water can be obtained.
This process is passive by nature, and the need for solar panels is no more require batteries or any other additional energy. The older water-harvesting technologies have been made limited to the areas having fog or other high-moisture conditions.Tags: devices, dry, energy, nature, Solar, water