A small wooden cube could soon be the only thing standing between you and a fresh glass of water. Scientists working at the Royal Melbourne Institute of Technology (RMIT) have created an outstanding new water harvester that pulls moisture from the atmosphere and then releases it when exposed to sunlight.
The little cube is especially noteworthy because it doesn’t require any kind of electricity to pull moisture from the air. This means it could be useful in places where power isn’t widely available, making water more accessible to millions. Another part of the breakthrough’s intrigue comes from the fact that it’s made entirely of wood.
The researchers say they took the lignin (which makes wood rigid) out of the wood, and this turned the water harvester into a spongy-like texture that is packed with microscopic pores. These pores are the framework for the device, which was then loaded with lithium chloride salt, which attracts water molecules in the air.
The other side of the cube was then coated in carbon nanotube ink, which is able to convert sunlight into heat. This is what helps the device turn the molecules into actual drinking water when placed in sunlight.
While many other water harvesters like this only work in humid environments, this particular device was able to work in an area with just 30% humidity, which is dry enough for it to work in desert regions where water is much more scarce. During testing, the device was able to capture roughly 2.5 milliliters of water per gram overnight.
It then released the water with a 94% efficiency when exposed to sunlight. The fact that this design doesn’t require significant infrastructure is what makes it such a sustainable option. Other options, like Aquaria’s recently revealed water generator, are also intriguing, but they require far more infrastructure to function.
Other attempts to create water harvesters like this include a gel that can pull water out of thin air.