Sustainability Problem: Water

Almost one third of the world population lives in arid regions where water is scarce. As population grows and climate heats up,  water scarcity has the capacity to create or amplify poverty, migration and conflict problems. Although the ability to extract clean water from air is not new, existing techniques require high moisture levels and a lot of electricity. There is a need for technologies that pull water from air in areas where the percent of humidity is low and potable water is a pressing need.

Technology: New system for extracting water from very low humidity locations

• Scientists at MIT and the University of California at Berkeley developed a new device that looks like a box. They used materials called metal-organic frameworks or MOFs, made of combinations of metal irons and organic units that act like a sponge to capture as much water as possible when the box is open. The structure of the MOF encompasses space, allowing the liquid to enter the interior of the porous. Once water is captured, the box is manually closed and exposed to some source of heat, which will heat up the material so it releases water from its surface in the vapor phase. The vapor is then converted to the liquid phase with a condenser.
• Tests showed that one kilogram (just over two pounds) of the material could collect about three quarts of fresh water per day, about enough to supply drinking water for one person, from very dry air with a humidity of just 20 percent.
• This is the first device that has potential for widespread use in dry locations that have a lot of sun.  Scalability is one of the main advantages of this technology in comparison to technologies that only extract water from very moist air, such as “fog harvesting” systems.

Stakeholders:

• Governments
• Academia
• Industries

Implementation:

• This technology is currently in the proof of concept phase. Initial experiments have proved that the concept work, but additional research is needed to refine the design of more effective varieties of the MOF.
• After additional experiments are conducted, the next phase will be scaling up the prototype so that the final product can produce enough water for a family of four.
• Later on, it will be necessary to develop a cost estimate and a business plan.

Sources:

• http://news.mit.edu/2017/MOF-device-harvests-fresh-water-from-air-0414
• http://money.cnn.com/2017/04/19/technology/future/solar-powered-device-drinking-water/index.html

Comment on another post

• Post: Nano Ganesh: Controlling your irrigation pump through your mobile device
• Comment: This device seems to offer an attractive and convenient option for farmers that would like to use their phones to switch irrigation pumps in remote areas, saving time that otherwise they would be spending commuting. In the website of the company, some farmers also claimed that the device saved overflowing of water. In 2015, the company announced the expansion of the device to urban settings to help residents plug wastage of water in the city.

Suellen Aguiar – ss195