One of my classmates, Shreerang Chhatre, is doing some very impressive work researching methods to harvest fog in regions without reliable supplies of drinking water.
From CNN:
Let’s say you live in a really dry area and you don’t have much drinking water. Meanwhile, you wake up every morning to the sight of fog floating by. Instead of walking miles and miles to get water from a faraway river, what if you could just extract drinking water from those low-hanging clouds?
That’s what a researcher at MIT is trying to make possible with new work to improve “fog harvesting,” the term for the process of getting water out of mist by using giant tarps made out of engineered materials.
The art of fog harvesting is simultaneously high- and low-tech.
To catch the fog, workers erect giant nets on stands of bamboo sticks or metal poles. This contraption catches the fog as it floats though the meshed material.
The nets don’t catch all that much water — about 1 liter for a net that measures 1 meter by 1 meter — but that’s enough to make a big difference in some parts of the developing world, said Shreerang Chhatre, a Ph.D. candidate at MIT who is doing research on materials that could improve fog technology.
“If you’re thinking from a Western point of view, from the point of view of a Western consumer who consumes 200 liters of water every day” then this technology doesn’t make much sense, he said. “In order to get that, we would need a humongous, huge surface. We want to get drinking water, water that is absolutely necessary for survival for people. That, we need in small quantities.”
From MIT News:
In the arid Namib Desert on the west coast of Africa, one type of beetle has found a distinctive way of surviving. When the morning fog rolls in, the Stenocara gracilipes species, also known as the Namib Beetle, collects water droplets on its bumpy back, then lets the moisture roll down into its mouth, allowing it to drink in an area devoid of flowing water.
What nature has developed, Shreerang Chhatre wants to refine, to help the world’s poor. Chhatre is an engineer and aspiring entrepreneur at MIT who works on fog harvesting, the deployment of devices that, like the beetle, attract water droplets and corral the runoff. This way, poor villagers could collect clean water near their homes, instead of spending hours carrying water from distant wells or streams. In pursuing the technical and financial sides of his project, Chhatre is simultaneously a doctoral candidate in chemical engineering at MIT; an MBA student at the MIT Sloan School of Management; and a fellow at MIT’s Legatum Center for Development and Entrepreneurship.
Access to water is a pressing global issue: the World Health Organization and UNICEF estimate that nearly 900 million people worldwide live without safe drinking water. The burden of finding and transporting that water falls heavily on women and children. “As a middle-class person, I think it’s terrible that the poor have to spend hours a day walking just to obtain a basic necessity,” Chhatre says.
A fog-harvesting device consists of a fence-like mesh panel, which attracts droplets, connected to receptacles into which water drips. Chhatre has co-authored published papers on the materials used in these devices, and believes he has improved their efficacy. “The technical component of my research is done,” Chhatre says. He is pursuing his work at MIT Sloan and the Legatum Center in order to develop a workable business plan for implementing fog-harvesting devices.