Brake/Lock

What can one do to save the windmill under these conditions? How do you stop it once it is going? At what speed of wind do you shut it down? Can one either by hand or with an electric motor and appropriate gears rotate the angle of the windmill so that it is perpendicular to the wind so that it comes to an almost stop. In stormy high wind conditions is it better to bring it to a total stop and tie down the blade? How does one do this? Are there any windmills designed to withstand higher winds? Ultimately, would the small or the large windmill fare better in high winds?

Offered by Mike.

There is a windmill (now 50kW capacity I think) by Bergey that can be put up and taken down by three people for repairs etc.

Offered by John.

Most decent wind generators will flare out at high speeds to prevent damage. The biggest problem won't be from the wind generator but from its tower blowing over. As far as braking and/or tying down, the instructions to do so will be with the wind generator. Each manufacturer may be different. 120mph is the highest speed most are rated, doesn't mean failure, just for the manufacturers, there was no reason to rate anything higher. Best thing to do would be to uninstall. Larger machines are more efficient, but will be harder to work with to install/uninstall. Sufficient diversion loads are generally built in to any decent wind generator.

Offered by Steve.

Some of the windmill models are equipped with braking devices that limit the speed of rotation. These brakes are used to lock the blades in high winds. Of course, here in Kansas, we rarely see winds of more than 100 mph, but that will change. I do not know what the limits are of these braking devices, or how they work, I just observe the windmills in the area that are not turning, though there is wind. A simple device could be built to measure the speed of the wind. Use a fan blade and connect it to a bicycle speedometer (via a gear on the 'axle' of the fan blade that has the correct diameter for the speedometer). When the speed approaches 120 mph, just apply the brakes.

Offered by Roger.