Another Way to Tilt at Windmills

Consider a circle of 100m radius. A breeze pushes air through it at a steady 36 km/hr. That represent wind blowing past with a total power content of ~ 20 GW *.


Following xxxx editorial slamming the practicalities of windfarms, it so happened I attended a brief talk on the potential for off-shore wind farming.

It proved to be an eye-opener. Not because the speaker was riveting (he wasn't), but for what he had to say about wind rotor technology; which was that no real innovations in design had occurred in nearly a century, and that a lot could be doen to rectify this.

Placement: putting the rotors *behind* the nacelle make the system a lot more responsive to wind changes, it also lends itself to:
Flexure: allowing the rotors to flex in response to the forces placed on it reduces the overall need for rigidity (ie weight)
Gearing: placing the motor at the bottom of the shaft further reduces the weight in the nacelle

* That reasonable figure translates to 3.14*100^2 * 29 *1000/22.4