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Why do wind power plants have just 3 blades? It seems that adding more blades would increase the area that interacts with the wind and gather more energy.

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(Image from Wikipedia.)

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marked as duplicate by dmckee May 13 '13 at 16:25

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

Short answer by (same) Wikipedia: 3-bladed turbines have high tip speeds of over 320 km/h (200 mph), high efficiency, and low torque ripple, which contribute to good reliability – Waffle's Crazy Peanut May 13 '13 at 12:49
I'm pretty sure I've seen 2-bladed ones as well. – Keep these mind May 13 '13 at 13:07
Also see Wikipedia: Blade count. – Keep these mind May 13 '13 at 13:09
up vote 5 down vote accepted

It is just easier, i.e. less expensive, to build and maintain them that way. There exist alternative designs that are more efficient but also more difficult (= more expensive) to build, put up and maintain. You can check those out via this link.

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why down-vote? so this isn't correct? – seb May 13 '13 at 14:57
+1: seems like a pretty good answer to me. – Mozibur Ullah May 13 '13 at 15:08

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