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Green Design: Inspired by Nature
Natural Forms of Flattery
From trains to air-conditioning systems, many of the amenities we’ve come to enjoy were inspired by nature.

Click on the images above for a slideshow.

FINESSING FINS
Humpback Whales Wind Turbines

Despite their gargantuan size (40 to 50 feet; 25 to 40 tons), humpback whales are surprisingly agile in the water. They swim in tight, concentric circles as they corral krill during mealtimes. Marine life biomechanics researcher Frank Fish (yes, that’s his name) discovered it isn’t the humpback’s skin, body structure, or muscle that allows it to move with such nimbleness, but its odd, bumpy fins. Contrary to popular belief, water tends to break up and form eddies as it flows over smooth surfaces. The humpback’s serrated fins guide water flowing over the surface into smaller channels, which consequently cuts down on turbulence and drag. Fish applied the design to wind turbine blades with success; wind tunnel tests showed an eight percent improvement in lift and 32 percent reduction in drag compared to smooth turbines. The blade’s manufacturer, Whalepower, states the technology increases electrical production by 20 percent while also reducing noise. The company hopes to apply the technology to compressors, pumps, and fans as well.

 

SLEEK BEAK
Kingfisher Train

When the Shinkansen Bullet Train of the West Japan Railway Company was developed in the late 1990s, it was one of the fastest trains in the world, reaching 200 miles per hour. With all that speed, however, came loud thunderclaps of noise caused by sudden changes in pressure as the train shot through tunnels, which caused residents up to 1300 feet away from the tracks to complain about the booming sounds. Eiji Nakatsu, the project’s chief engineer, looked to nature for inspiration and found it in kingfishers. Known for their spectacular diving skills, these brightly colored birds barely make a splash as they plunge into rivers, lakes, and estuaries after small fish. Nakatsu and his engineering team digitally mapped the kingfisher’s body and discovered its beak was the ideal shape to cut through sudden pressure changes like those in water—or tunnels. The train, now equipped with a nearly 50-foot kingfisher-shaped nose, is not only quieter, but it also uses 15 percent less electricity while traveling 10 percent faster.  

 

FREE FLOW
African Termite Mounds Air Conditioning Systems

Termite mounds can be found in some of the most variable climates on earth, including the deserts and grasslands of Sub-Saharan Africa where temperatures can swing between 107ºF and 37ºF from day to night. Yet the inside of these intricate nests, which are made of dirt, grass and shrubs, remain relatively constant at roughly 87ºF, thanks to a network of precisely placed tunnels that allow for constant air flow. Architects tapped into the design of these natural cooling systems for the Eastgate Building, an office-retail building in Harare, Zimbabwe, to eliminate expensive, climate-impacting air conditioning.  Architect Mike Pearce and engineers at Arup Associates created a network of ventilation tunnels that allow air from outside to flow freely through the building without using electricity. The result is a system that traps chilly evening air inside for cooling during the day and warm daytime air for heating at night. This system, along with reduced solar glazing on windows and light-colored construction materials—both of which reflect heat—have enabled the Eastgate Building to use only 10 percent of the energy of a conventional structure its size. The facility saved nearly $3.5 million in air conditioning costs during its first five years of operation.  

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