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Old 15th-February-2008, 04:05 AM
atdub atdub is offline
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Quote:
Originally Posted by Windguy
So solar is now reaching 30% efficiency where as wind is still about less than 1%.
Hi Windguy,

I'd have to disagree there.
Power in the wind can be calculated using:
P(WATTS) = (1/2)*density*Area*(velocity^3)

so for say 10m/s @ 1.225 kg/m^3 we get Power = 612.5 Watts/m sq

From the vestas V90 power curve, the V90 can generate approx 1500kW at 10m/s. This is over the entire swept area of the blades so per m2 = power output / swept area

1500000/6362 = 236W / m sq

which is ~40% of the actual power in the wind. There are some assumptions here but it shows the efficiency is much higher than 1%.

"Backyard" wind turbines are quite easy to make using electric motors that are used in everyday household electronics, plus they are quite simple devices anyway. A solar cell on the other hand obviously requires much more complex processes than jamming a fan on the end of a motor and holding it up high!
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