The Sycamore Seed and the Maple Seed

We've been doing the ceiling fan thing all wrong for all these years. Turns out the best design for a fan blade is to twist it into the shape of a seed pod from a Sycamore tree. Spin it around at just 70 to 130 revs per minute, and you get the same airflow as a regular fan cranking its heart out at twice that speed. We're also digging its weirdo looks, too.

You can get these in Australia, but expect this technology to spread far and wide before too long. Someday all fan blades will be made this way. Hey, somebody, pick up this blade design for a PC case fan, and then half the RPMs will equal half the noise. – Charlie White
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I remember when I was kid getting such a kick when there was a big gust of wind and all the dried seeds would come twirling down like waves of little helicopters from the trees. Well apparently nature has the right idea, because it turns out the design of a Sycamore seed makes for an extremely efficient ceiling fan. It creates the same air flow with less noise and at slower speeds than traditional fans, and because it runs slower the natural form and beauty of the dynamically balanced blade is visible even when the fan is in use.

"As best demonstrated by Nature in the case of the aerofoil maple-seed, today's propeller is a pressure-screw and therefore a braking screw, whose purpose is to allow the heavy maple-seed to fall parachute-like slowly towards the ground and to be carried away sideways by the wind in the process. No bird has such a whirling thing on its head, nor a fish on its tail. Only man made use of this natural brake-screw for forward propulsion. As the propeller rotates, so does the resistance rise by the square of the rotational velocity. This is also a sign that this supposed propulsive device is unnaturally constructed and therefore out of place."

– Viktor Schauberger, Implosion Magazine, No. 112, p. 52

http://www.luxist.com/2007/06/22/sycamore-ceiling-fan/
http://gizmodo.com/gadgets/highly-efficient/radical-ceiling-fan-blade-mo...