Searching for Water in an Untapped Source: the Air
As climate change and the needs of 7 billion humans increase demands on the global water supply, the pressure is on to come up with ways to squeeze water from a stone—or at least from the air. The Airdrop is a new gadget that steps up to the challenge by helping farmers in severely dry regions source water for irrigation systems by harvesting moisture that's evaporated into the ether. Edward Linnacre, the engineering student behind the project, won this year's James Dyson Award for creativity in engineering design for his low-tech solution to a grave problem.
The scientific principle guiding the technology is one that anyone who's seen dewy leaves in the morning can understand: condensation. As Linnacre explains in an elevator pitch on YouTube, "There's just an abundant resource of water in the air that surrounds us, even in places like the Negev desert in Israel, which is one of the driest deserts on the planet... All you need to do is reduce that air down to a certain temperature and you release that moisture." While other machines that do the same job are expensive and technologically complicated, the Airdrop is so simple that rural farmers could set it up themselves.
Air enters through a turbine sticking out of the ground and is pushed underground through a series of pipes. The air cools as it approaches the much-colder soil beneath the ground. Water condenses, dripping into a holding tank below. The final step is a connection to a drip irrigation system, "putting the water back into the roots of plants where it belongs, and where it has evaporated from," Linnacre says. The Airdrop was inspired by devastating droughts in Linnacre's native Australia, so let's hope it can make a difference there and for farmers around the world.
Photo via Facebook