Are the sub $300, 400w wind generator from china/ebay worth it?

[NeilBlanchard]

The wind cools the panels, and that raises their efficiency.

[nibs]

In the 1980's I built about 600 wind machines, with 4ft diameter blades, I rated them as 200 watt machines because they developed about 20 amps at 12 volts in 20kts wind.
They were very efficient, I developed the blade from NACA 0010 foil then modified it to suit the PM generators I used.
The market was a really good one, and about the only place I would still recommend a wind machine over PV panels. Sailboats, my unit was designed to hang in the rigging, when at anchor. Quiet reliable and at a base price of $250 1980 dollars was affordable.
Two days ago I took apart the generator of one I built ...30+ years ago and the insides were in very good condition, the generator now gets used as a 12V motor to pump water.

[pinballlooking]

Originally Posted by nibs

In the 1980's I built about 600 wind machines, with 4ft diameter blades, I rated them as 200 watt machines because they developed about 20 amps at 12 volts in 20kts wind.
They were very efficient, I developed the blade from NACA 0010 foil then modified it to suit the PM generators I used.
The market was a really good one, and about the only place I would still recommend a wind machine over PV panels. Sailboats, my unit was designed to hang in the rigging, when at anchor. Quiet reliable and at a base price of $250 1980 dollars was affordable.
Two days ago I took apart the generator of one I built ...30+ years ago and the insides were in very good condition, the generator now gets used as a 12V motor to pump water.

Do you have any pictures of them.

[Robaroni]

Originally Posted by NeilBlanchard

The wind cools the panels, and that raises their efficiency.

Thanks Neil, I didn't know that.

Rob

[Robaroni]

Originally Posted by nibs

In the 1980's I built about 600 wind machines, with 4ft diameter blades, I rated them as 200 watt machines because they developed about 20 amps at 12 volts in 20kts wind.
They were very efficient, I developed the blade from NACA 0010 foil then modified it to suit the PM generators I used.
The market was a really good one, and about the only place I would still recommend a wind machine over PV panels. Sailboats, my unit was designed to hang in the rigging, when at anchor. Quiet reliable and at a base price of $250 1980 dollars was affordable.
Two days ago I took apart the generator of one I built ...30+ years ago and the insides were in very good condition, the generator now gets used as a 12V motor to pump water.

I'm going to try and put together a couple of 8 to 10 footers if I can find the time this summer. Did you wind your own alternators?

Rob

[nibs]

Rob, I used tape drive motors which are no longer available in any quantity, and the manufacturers would not make them for me because of liability.
We enclosed them in stainless housing with tapered stanchions for the mounting.

Be careful with 8ft blades I made a 7ft blade out of a 2X6 clear doug fir, I cut it away near the hub to get a nice steep angle for starting, with about a 1/2 degree washout at the tip. The tip chord was about 3" and about 3/8" thick. you must taper the trailing edge to be sharp, or it will moan and the neighbors will moan almost as loudly. An 8' blade is not trivial, be careful.'

[Robaroni]

Originally Posted by nibs

Rob, I used tape drive motors which are no longer available in any quantity, and the manufacturers would not make them for me because of liability.
We enclosed them in stainless housing with tapered stanchions for the mounting.

Be careful with 8ft blades I made a 7ft blade out of a 2X6 clear doug fir, I cut it away near the hub to get a nice steep angle for starting, with about a 1/2 degree washout at the tip. The tip chord was about 3" and about 3/8" thick. you must taper the trailing edge to be sharp, or it will moan and the neighbors will moan almost as loudly. An 8' blade is not trivial, be careful.'

Thanks,
Yes, I know I've built windmills, I see these people who never built a mill thinking they're going to built 20 footers. Yikes, that's a lot of mill!

I wind my own motors from old AC motor cores that I get at the local motor rebuilding shop. They saved me a 5HP one that will work great for my microhydro and my mills. I don't especially like the flux core alternators. They're OK if you don't have a machine shop like I do but they have inherent problems.

Noise isn't a problem, my nearest neighbor lives about 1/4 mile away. That's one of the bennies of living out in the county, I can do just about anything I want and no one gripes.

Rob