The recent 12-year drought in Australia’s Murray-Darling basin was the worst in a century and it hit crops hard. You can’t grow food without water. So what’s a farmer to do? Maybe pull water out of thin air.
The AirDrop takes advantage of the fact that even in the driest places, there’s still moisture in the air. A turbine at the top of the device pulls in warm air and moves it underground. As it descends, the air passes through a copper coil and cools to the temperature of the surrounding soil, causing the moisture in the air to condense into drops of water. That water collects in an underground reservoir where it is pumped directly to the roots of crops via a low-pressure drip irrigation system.
The turbine can run without power given sufficient wind. In still conditions, it runs on a solar battery. The AirDrop also has an LCD screen that displays water levels and battery life.
Other "atmospheric water harvesting" devices exist, but they tend to be big, expensive, or high-tech. The AirDrop is relatively low-tech, which Linacre hopes will make it easy for rural farmers to install, use and maintain.
The James Dyson Award, named for the bagless vacuum cleaner inventor, challenges entrants to simply "design something that solves a problem." For solving this one, Linacre will get a $16,000 prize himself and another $16,000 for his alma mater, Swinburne University of Technology in Melbourne. Linacre plans to use the funds for further testing.
And let’s hope that testing goes well. Australia isn’t alone. Encroaching deserts are going to be a problem in Africa and central Asia as well. If we can’t stave off climate change entirely, perhaps innovations like this can at least help us mitigate starvation.