Water Off a Beetle’s Back…

What do a cactus, a desert beetle and a pitcher plant add to?

How about a wonder material that could be used to improve the efficiency of power plants and harvest water from thin air? This is the answer researchers at the Harvard John A. Paulson School of Engineering and Applied Science (SEAS) and the Wyss Institute for Biologically Inspired engineering have given after researching each of these biological systems.

The desert beetle has been a subject of academic interest for a while in its ability to harvest water from the air using the bumps on its back. It was assumed that this ability stemmed from hydrophilic (water-attracting) material on the bumps. However, this research found that the geometry of the bumps could alone cause condensation to form.

The team used this to derive an optimal geometry for water harvesting, using computational modelling, and then to produce a truly innovative material. “[We] combined the asymmetry of cactus spines and nearly friction-free coatings of pitcher plants… [to] design a material that could collect and transport a greater volume of water in a shorter time” says Kyoo-Chul Park, the first author of the paper.

The applications of harvesting and controlling the transport of water droplets are diverse. For example, in industrial heat exchangers where steam is converted into water this technology could speed up the process, allowing the exchangers to work at higher temperatures and so run more efficiently. However it is not just the wide reaching applications that make this research significant, but also the “complex bio-inspired approach” which considers many different biological systems to produce useful technologies, which could mark a new era in bio-mimetrics.

Photo: http://www.asknature.org/strategy/dc2127c6d0008a6c7748e4e4474e7aa1