Scientist develops self-filling water bottle

Added by on November 21, 2012

Water drop on hydrophobic leaf surface

A scientist on Wednesday released details a water bottle he invented that fills itself by extracting water from the surrounding air.

The scientist says the invention was inspired by the Namib Desert Beetle which survives in the arid desert climate, in part, by extracting water from air that passes over the beetle. Water condenses on specific areas on the beetle’s back and flows into a storage area on the beetle.

In an interview with Public Radio International, the scientist said he uses “…nanotechnology to mimic this beetle’s back so that we too can pull water from the air.”

An analyst explained the new surface was created using special coatings that mimic the beetle’s back – the surface causes water to condense when air, circulated by a fan, passes over it.

“We see this being applicable to anything from marathon runners to people in third-world countries, because we realize that water is such a large issue in the world today, and we want to try to alleviate those problems with a cost-efficient solution,” said the scientist.

An analyst explained the idea of extracting water from the air is not new: water harvesters that work in fog have been in development for a long time, as have other types of water harvesters. Fog harvesters are known to be able to extract about one liter of water per day using a one square meter of mesh.

“Air carries about 1g of water per kilogram of air, so you’d need to pass about 1,000 kg, or 1,000 cubic meters, of air over the surface to harvest one liter. The speed of the air is also a factor, since the water bottle should ideally be filled in a reasonable amount of time,” said an analyst.

All of the air on Earth reportedly holds approximately 11 quadrillion liters (3 quadrillion gallons) of water; the total volume of air on Earth is 5,140 trillion tonnes (5.6 tons).