Pneumatic wind mill

[Bushman]

My brother in law and I where talking about building a pneumatic wind mill made with PVC pipe a Check valve a tube and some old air tanks.
 I would use a old school wind mill. ( my wife really wants one ) I would build a simple PVC piston connected to. A Check valve that would pump air down a cheap plastic  pneumatic tube to an old air compressor tank. You could put as many in line as you would like. The stored compressed air would act as a battery that could power many air tools.

Air motors are cheap and easy to come by. Maybe you could retro fit a generator to be turned by a air motor. I have talked to many people about this and the more I talk about it and research it it seems like a cheap way to go for an extra source of energy.

Has anyone tried this idea? Anyone have any reasons that it would not work or maybe other uses for this kind of system.

[Bolomark]

probably not very efficient you would have to be able to store a lot of CFM which would be used by an air tool very quickly.
then wait while the windmill fills it back up.

[Bushman]

For me in my situation the mass amount of stored air is not that much of an issue. I have 7 100 gallon tanks. With full pressure of  150 to 200 psi that is a lot of stored energy. Many air tools use large amounts of air. Many do not. I could probably run a water pump for about 30 minutes on a full charge. That was the original idea to use the air to make enough pressure so that I could water my garden.

[Bolomark]

give it a whirl. literally

[strangetanks]

I've thought about this same thing.  To me it makes more sense to store mechanical energy as mechanical energy.

Here's the hard part in my mind.  2 things I think you would want to figure out.

First you would want some kind of transmission that would gear up your compressor to pump faster at low pressure and slower but with more torque as the pressure got higher.

Second, if you could figure out a way to fill your tanks one at a time. For example, bring the first tank up to 100 psi then the extra air would start dumping into the second tank until that one came up to pressure....ect.  That way you wouldn't have to wait a week to get up to operating pressure.

[Perfesser]

Probably the best use of wind power but a few things come to mind right away.

This thing could run for days on end, I think you'll need lubrication. You might get away with water lube on your PVC. Or a small compressor head(not an oil-less). Probably need some kind of low power centrifugal clutch like for a go-cart to get things spinning before engaging the compressor.
Use an inline pressure relief valve after the first tank to pipe excess air into the second (or more) after the first is at full pressure.

[TheRetiredRancher]

There is a commercial windmill that has a compressor directly powered by the fan.  The high pressure air then powers a jet pump to lift the water out of the well.  Google windmill and jet pump together and you can probably find it pretty quickly.  It was slightly cheaper than a conventional windmill but if I remember right it was about $15,000.  It would not lift water from deep enough for me so I went solar.  I think jet pumps are good to about 200 feet, but look it up don't trust my poor memory.

[Bushman]

Cool stuff and great info. I was thinking of use ing solinoids with a priority order to fill each tank in line one at a time. From there I was looking at automating a system that would drive a air motor that would drive a magneto from a generator and store it into battery's for electricity. Now the cool thing with use ing air motors is that you can transfer the air from one full tank to another tank and not lose the stored energy you are just use ing the difference in pressure between the two tanks to run your motor. So by use ing just two tanks that are full you could gain 50 percent energy out put. I am not saying that it would or would not be more efficient then an eletric wind mill but if you have a pneumatic windmill this would be a better way of use ing the power. I have thought of use ing a small compressor head as the drive for the air. As long as you have a small enough of a compressor and a wide enough windmill you should be fine even with a light wind to turn the compressor.  You may need a Check valve to off load the pressure from a dead re start. I have found at tractor supply a 15 ft windmill that has a aeration pump for ponds built in to it. It cost 1200 bucks, I thought that would work for the time being. I hope I'll have time this summer to build this system. When I do I'll post pics.

[TheRetiredRancher]

Please post the pictures.  It sounds like an interesting project.