On 18 Sep 2006 00:54:57 -0700 someone who may be "robgraham" wrote this:-
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shows a range of turbines with a cut-in speed of 3m/s, a rated speed of around 9m/s (depends on model) and a maximum speed of 40m/s (70m/s on the largest model).
For comparison large turbines tend to cut-in at around 4m/s, be rated at around 14m/s and shut-down at 25m/s.
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give average values, when it works.