Okay, so this one has been drifting around in my head since high school. I keep thinking that any day now I'll come across it in some alternative energy article but the decades pass and I don't. Maybe I'm missing something obvious. Some lethal flaw. Maybe not.
Build a wing cross section. Just for this case let's say that it's two meters long and half a meter from leading edge to trailing edge. Just to keep it simple, the cross-section stays the same from left to right.
Place the wing parallel to the ground with a piston on each side. Put the whole thing on a turntable with a vertical wing above and below to keep the turntable facing into the wind. The wing points slightly downwards such that the wind will push the wing down, just as we've all learned from keeping one hand sticking out of the window of a moving car. The piston has a ratchet so it can go down but not up. As time passes, the wing will push the piston down to the end of its range of travel.
Now it reaches the bottom.
The ratchets realign and the wing does too. Now the wing points slightly up, so the wind will push it to the top of the range of travel of the piston. Up it goes until it reaches the top.
And back down. And up. Forever and ever. Or at least until it breaks.
I'm simplifying the mechanism to explain what it does. Obviously, the whole thing could use chains or cables instead of pistons, the ratchets can be done without in plenty of variants as long as the wing can realign, etc., etc., etc.
So, there are plenty of wind turbine designs out there already. Why should anybody care about this one?
A - Done right, it should be almost silent. Even the realignment can be muffled. In fact, the wing can be built of fabric or something equally plastic and the realignment done just by shifting cable tensions. Motion, typically, can be set to be slow, almost drifty. It's all about how you tweak the pressures needed, ratcheting, and so on.
B - It can be horizontal, not vertical. No complaints when put on a rooftop that it's ruining everybody's view.
C - it can happily sit in intermittent wind of changing speed and direction, blithely pushing up and down, up and down, a simple little pump that just keeps generating power or pumping water or what have you, no matter if it's a quiet spring day or a hurricane. Yield will change but it won't need to shut down or, if built right, get damaged by high winds.
D - It can be built of inexpensive materials. Simply. Any airplane modeler knows how to build a wing. In fact, most of it, including the pistons, pump, etc. can in many cases be built of surplus. Just to test this, I built a test section of wing with steel guide rods back around '88 and it was just as simple as I had expected it to be. Fiberglass from Canal Plastics for the skin. Cut pieces of MDF for the supports. Doped with whatever I had sitting around. I stuck to a 90 degree realignment so the ends of the guide rods were, woo-hoo, squares. No biggie.
Of course, one could spend the rest of one's life coming up with eccentric gears and cogs and sprockets for variations on the beastie but afaic, that's a feature, not a bug.
Just a simple design for a wind turbine. Simple, low profile, almost silent. Suited to cities and areas with more handcrafters than money. I would love to see it start turning up in cities. And over the shops of ambitious auto mechanics in countries most of us haven't even heard of.
Anyway, make of it what you will. There it is.