Getting water from fog: Shorebird's beak inspires research on water collection

The device could provide water in drought-stricken areas of the world or deserts around the globe.

Xin Heng, left, a doctoral student in Mechanical and Aerospace Engineering, and Cheng Luo, MAE professor, have made a device that can use fog and dew to collect water.

Cheng Luo, professor in the Mechanical & Aerospace Engineering Department, and Xin Heng, PhD candidate in the same College of Engineering department, published "Bioinspired Plate-Based Fog Collectors" in the Aug. 25 edition of ACS' (American Chemical Society) Applied Materials & Interfaces journal. 

The idea began when Heng saw an article that explained the physical mechanism shorebirds use to collect their food -- driving food sources into their throats by opening and closing their beaks. Luo said that inspired the team to try to replicate the natural beak in the lab.

"We wanted to see if we could do that first," Luo said. "When we made the artificial beaks, we saw that multiple water drops were transported by narrow, beak-like glass plates. That made us think of whether we could harvest the water from fog and dew."

Their experiments were successful. They found out they could harvest about four tablespoons of water in a couple of hours from glass plates that were about 26 centimeters long by 10 centimeters wide.

Shorebirds refers to a general category of bird that lives on the world's shorelines. They typically have long, hinged beaks that are designed to ferret around for prey whether in the sand or the water.

Luo said the hinged, non-parallel artificial beaks the team made in the lab mimic the shorebirds' beaks, forcing the condensation to the point where the two glass plates meet. The water is pumped through a channel, and then the process is repeated.

Luo and Heng said more sustainable methods are needed for accumulating water in arid or semi-arid places, which make up about half of the world's land mass.

"And really, if this method could be mass-produced, it could be used anywhere in the world fog or dew exist," Luo said.

Khosrow Behbehani, dean of the College of Engineering, said the research could help drought-stricken areas like Texas and California.

"The research shows innovative ideas can be triggered by careful observation of seemingly unrelated phenomenon," Behbehani said. "Collecting water from existing fog or dew using this novel method offers another alternative for communities that are strapped for our most precious resource."