LASN is a photographically oriented, professional journal featuring topics of concern and state-of-the-art projects designed or influenced by registered Landscape Architects.
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110 Landscape Architect and Specifier News I n f o r m a t i o n R e q u e s t # 5 5 5 "Where there's a will, there's a way," it's said, but it also holds that "Where there's a need, there's a way." The need in the Atacama Desert plateau on the coast of Chile is fresh water. This "oldest desert on Earth" receives about a half-inch of annual rain. The "way" may be a water collection idea devised by researchers at MIT's School of Engineering, and colleagues at the Pontifical University of Chile in Santiago. They have repurposed and refined a method used by some native plants and insects here to capture water from the prevalent coastal fog, la camanchaca, which moves inland to provide enough moisture to grown algae, lichens and even some cacti. The bug inspiration for the researchers is the Namib beetle, whose bumpy and troughed winged back effectively collects water from the fog. One of the local flora inspirations is Casuarina equisetfolia, whose thin pine needle-like branchlets are good at capturing fog as water droplets. The challenge for the researchers was how to emulate this biology (biomimicry). The research engineers experimented with variations in mesh fiber wettability and spacing. A woven polyolefin, a common inexpensive plastic, collects 2 percent of the fog, while finer mesh collects as much as 10 percent. Experiments determined a fine mesh of stainless-steel filaments about 3-4 times the thickness of human hair worked best. This inexpensive to manufacture mesh, coupled with a "proper coating" improved efficiency by 500 percent. The netting yields two liters of water (desalinated by the sun) a day per square meter of mesh. Researchers believe they can get that figure up to 12 liters per day. Top: The Chilean coastal fog, "camanchaca," moves across the Atacama Desert and hovers over the inland mountains. Researchers are using a fine netting of stainless-steel filaments to capture droplets of water from the thick fog, which is then harvested for potable and irrigation use. There is also a company devising a water bottle to basically do the same thing. Bottom and Inset: Collecting water from Chilean coastal fog is inspired by flora and fauna of the region like the thin pine needles of Casuarina equisetfolia, and the Namib beetle, whose bumpy back and trough-like grooves capture water from the mist. Water from the Mist—Employing Biomimicry