Wind energy - Wind vane

A wind vane is a simple but clever device employed to passively point something in a desired direction relative to the wind.

They work like a flag. Always trailing away from where they are fixed, being carried with the wind.

If we make a rigid flag, it's a wind vane.

If we stick something to the front edge of the wind vane, (where the flagpole is if it was still a flag) we can make that thing face the wind. So for instance if we nailed a sign to the front edge at 90 degrees, the wind would be able to read it.

Rather than a sign, we can stick a wind turbine on to face the wind.

Anything you stick out in the wind wants to act a bit like a wind vane.

Even our windmill blades.

Without the wind vane, the windmill would act like a wind vane itself and would probably loose its sense of direction.

By placing our wind vane at the end of a long pole, we gain a mechanical advantage. Leverage in this case. What that means is a little wind vane at the end of a long stick can overcome the wind's attempt to ruin everything. The little vane at the end of a long stick can stay downwind even though the big windmill wants to be downwind as well.

As long as the entire contraption can rotate freely on the pole that keeps it all up in the air, it will always point the windmill directly into the wind. If the wind changes direction, the windmill rotates and always points the turbine correctly.

I love it when people invent things that use the force they are trying to counter against itself. I realize this is a pretty simple invention, but it was still very clever of whoever thought of it in the first place.

"I wish the wind would stop blowing my windmill out of the wind. I know, I'll just use the wind to point my windmill into the wind."

That's good brain using.

So now we have a better method of making our wind turbine track the wind without having to run outside and re-point our windmills into the wind every time the wind changes direction (the Dutch were a big fan of the running outside method in their early designs). What we need now is a way to point it out of the wind when there is too much of the stuff, without having to run outside. (the Dutch did a lot of running outside to save their windmills from too much wind by furling their windmills.) (actually I think the Dutch windmill operators were live-in like a light house keeper, so they probably didn't go outside so much. They probably just adjusted everything from inside - but I'm pretty sure there was a lot of running around, and constant attention and vigilance involved)

What we need is a method of automatic furling.

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