Water – fresh and clean – is something we humans need. Without it we’re sick or dead. Drilling deeper wells will work for a while, but that’s expensive and once we use up deep aquifers they’re gone for our lifetime. Desalination sounds like the perfect answer – but it’s also expensive and if the salty concentrate is dumped near the intake (as it usually is) the water becomes harder to treat.
Oh, for nature’s pure water, freely given from the sky. Ten percent of Earth’s fresh water is floating around in the air at any given time – so close at hand but so hard to reach. Maybe until now.
You can’t squeeze blood from a stone, but wringing water from the desert sky is now possible, thanks to a new spongelike device that uses sunlight to suck water vapor from air, even in low humidity… homes in the driest parts of the world could soon have a solar-powered appliance capable of delivering all the water they need, offering relief to billions of people. sciencemag.org
The device is powered by solar energy – abundant in poor dry communities. It requires zirconium-based, porous organo-metallic crystals pressed onto sheets of copper. Hmmm, that sounds harder to come by. Indeed, it’s too expensive right now, but researchers at University of California, Berkeley, are
Designing future water harvesters cheap enough not only to slake the thirst of people in arid regions, but perhaps even supply water to farmers in the desert.
Too often, scaling up a lab success proves disappointing. That’s why a lot of the “breakthroughs” you read about in the popular press are never heard from again. But so many people need water. I hope this idea works out.
Here’s my ode to a champion desert dweller, the desert watermelon. I hope this new idea is an effective.
Kate's Science - Real and Fantastic 