Hugh Pickens writes writes: "BBC reports on a recent startup that is developing a self-filling water bottle capable of storing up to three liters every hour. Using nature as an inspiration for technology NBD Nano is looking at the Namib Desert Beetle that harvests moisture from the air to survive and using a similar approach, covering the surface of a bottle with hydrophilic (water-attracting) and hydrophobic (water-repellent) materials. The Namib Desert Beetle uses its back to extract its water supply from morning fogs. Wind pushes the moisture into the peaks of the beetle’s back until enough condensation builds up to form droplets of water. "It was important to apply [biomimicry] to our design and we have developed a proof of concept and [are] currently creating our first fully-functional prototype," says Miguel Galvez, co-founder of NBD, "We think our initial prototype will collect anywhere from half a liter of water to three liters per hour, depending on local environments." In some countries, condensation devices on rooftops already harvest water from the air — but these technologies consume large amounts of energy to produce small amounts of water. NBD Nano's prototype seems to be more energy-efficient says Erik Harvey from WaterAid charity adding that although the process would not be able to satisfy the needs of an entire community it doesn't mean the start-up is wasting its time. "There is a range of viable markets for them, like the military or the outdoors market, people going camping, and the advantage that they may have is a much lower energy input device.""