MIT engineers have developed an ultrasonic device that rapidly releases water from sorbent materials used in atmospheric harvesting.
By shaking water molecules free instead of heating them, the system boosts efficiency dramatically. Powered by a small solar cell, it could run multiple cycles per day. The advance could make off-grid, air-powered drinking water systems far more practical.
Feeling thirsty? It may be possible to draw drinking water straight from the air. Even very dry places still hold small traces of humidity that the right materials can capture and release as clean, drinkable water.
In the last few years, researchers have created many sponge-like materials capable of this “atmospheric water harvesting.”
However, getting the collected water back out of these materials typically involves heat — and patience. Most systems depend on sunlight to warm the material until the trapped moisture evaporates and condenses into liquid form, a process that can stretch on for hours or even days.
MIT engineers now report a way to speed up this recovery step. Instead of relying on sunlight to coax water out, the team uses ultrasonic vibrations that physically shake the moisture free.
