Water, Sewage & Effluent March April 2019 | Page 41

www.waterafrica.co.za
From thin air
A team from UC Berkeley and the
Berkeley National Laboratory created
Water Sewage & Effluent March/April 2019
39
innovations
Scientists at the University of California,
Berkeley, have developed a device that
can suck water out of desert skies,
powered by sunlight alone. They hope
that a version of the technology could
eventually supply clean drinking water
in some of the driest and poorest parts
of the globe.
There are two main ways that technology
looks to alleviate the impending water
crises unfolding in arid and tropical
nations alike.
One is by using technology to make
water-intensive processes more efficient.
Agriculture, industrial manufacturing,
and many other large-scale processes
use massive amounts of fresh water and
often contaminate or otherwise waste it in
ways that render previously potable water
useless or even harmful for life on earth.
The other is by using technology
to create fresh water — including in
some remarkably science-fiction ways.
From filtering saline ocean water and
purifying water that was once deemed
permanently toxic, to pulling water
from ‘thin air,’ even in arid climates,
technology promises to save water in
multiple ways.
a device that is entirely passive and
collects water from the atmosphere in
desert environments that routinely see
single-digit humidity measurements.
Using a material called metal organic
framework (MOF), the team built box-
shaped devices that use ambient heat
and the radical temperature swings in
desert environments to gather what
moisture there is in the air and then
condense and release it using natural
heating and cooling as well as spikes in
humidity levels.
The key breakthrough here is the
ability to create a material that can
absorb meaningful amounts of water
from some of the lowest-humidity air in
the world; these are the places that most
naturally experience water shortages.
Researchers are currently working to
perfect the MOF materials to increase
their efficiency, reduce costs, and create
devices that can be scaled to make a
meaningful impact in desert regions from
Arizona to Saudi Arabia.
As Omar Yaghi, who invented the
underlying technology, says, there is
nothing like this. “It operates at ambient
How technology can help
with water crises
Perth Seawater Desalination Plant.