84 DISCOVERMAGAZINE.COM
JAY SMITH
TECH
It’s Raining Water Harvesters
The World Water Council estimates over a billion
people don’t have clean, safe water. Technology’s
answer: Let’s harvest it from the air. Expect to hear
more about solutions like these 2018 inventions.
CITY SLICKERS
« MIT researchers
unveiled a mesh that
uses electric fields to
attract and condense
water in fog.
« The researchers say it
will capture 150 million
gallons of clean water per
year from the discharge of
industrial cooling towers,
like the ones on rooftops
that expel heat from air
conditioning.
« A pilot test on a
cooling tower at MIT is
under construction and
should be operational
in 2019.
Bonus!
GRAPHENE
GREATNESS
« An international team
of engineers collaborated
on a device that uses solar
power not to harvest
water, but to purify and
desalinate it.
« Its design is simple: The
sun heats graphene — a
sheet of carbon atoms —
which creates steam from
salt water that then can be
harvested as clean water.
NIFTY NANO
« Canadian researchers
introduced another water-
harvesting mesh, this one
using carbon nanotubes
to separate water vapor
from air.
« The company, Awn
Nanotech, claims its device
can harvest up to 100 liters
per day.
« The mesh hit the
market this fall, so a water
harvester can be yours for
just $1,000 a pop.
HEAVY METALS
« A team from the
University of California,
Berkeley, invented a
harvester that uses a highly
porous metallic powder
to collect water at night.
« During experiments in
the Arizona desert, each
kilogram (about 2 pounds)
of powder reportedly
produced nearly half a cup
of water every 24 hours.
« The team has already
scaled up the technology
and adapted it to cheap
and readily available
materials. Next up:
commercialization.
MIT’s mesh
in the lab
Graphene
and
salt water
Metallic
powder
Carbon
nanotube
mesh filter
Clean water
Simulated
fog
Collected
water
Collected
water
Collected
water