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

[AC_Hacker]

Originally Posted by Robaroni

...My thinking is that instead of one windmill up 80 feet, I'll put up a couple of 10 footers up 40 feet or so...

Your idea of more than one windmill at a lower height is reasonable, but I think that if you did a bit of research into the issue, you will find that 2 windmills at 40 feet does not equal 1 windmill at 80 feet. I don't know exactly what the relationship is, but I think that you will find that it takes 3 or 4 windmills at 40 feet to equal 1 windmill at 80 feet.

-AC

[stevehull]

Rob,

Wind power has always excited me. The concept of capturing and transducing potential kinetic energy, that goes up exponentially with wind speed, is just magnificent. Incredibly captivating.

But this thing REALLY needs to be up high in order to capture what is called "clean air" that is not turbulent and is free of ground effect . . .

I spent many hours (likely scores of hours) in my youth on top of 60-80 foot towers putting up antenna rotators, four element Yagi beam antennas and doing the necessary cabling. Worked on upright towers with "gin poles" and also on "tilt over" type towers.

Ham radio was great and it taught me a lot about practical and theoretical issues having to do with many aspects of high frequency radio.

Some of the very practical things. I never got injured, but I saw some terrific injuries. I didn't have fear height, but one mistake up there and you are toast. I saw people loose footing and only by the grace of god did they survive.

I would FAR rather work on a roof and have as my only problem a sunburn from the reflected sunlight.

I appreciate the enthusiasm, but I am rather done climbing up on towers and lifting multi hundred lb devices that turn about . . .

Guess I am weannie!

But I sincerely DO encourage you to try it!

Steve
ps just get a VERY good climbing harness . . . .

[Robaroni]

Originally Posted by AC_Hacker

Your idea of more than one windmill at a lower height is reasonable, but I think that if you did a bit of research into the issue, you will find that 2 windmills at 40 feet does not equal 1 windmill at 80 feet. I don't know exactly what the relationship is, but I think that you will find that it takes 3 or 4 windmills at 40 feet to equal 1 windmill at 80 feet.

-AC

Thank you both for your views. Yes, I know that two windmills at 40' don't equal one 80' mill. The shear winds at 40' are greater too and maybe a VAWT might be a better option for shear winds.
I'm happy getting less power with two mills much lower without the cost and maintenance of the higher tower.
The other thing is that I've been doing site surveys for several years and I do have the average wind speed here to benefit from wind. That with my ability to inexpensively produce windmills ( I figure under $300.00 each with blades) makes wind viable for me, especially now that I have my PV in.
Microhydro will go in this summer too and this should round out my energy very well (I hope!)

Steve,
I've put up several ham antennas too. (W2IE)
Rob

[pinballlooking]

Originally Posted by Robaroni

Thank you both for your views. Yes, I know that two windmills at 40' don't equal one 80' mill. The shear winds at 40' are greater too and maybe a VAWT might be a better option for shear winds.
I'm happy getting less power with two mills much lower without the cost and maintenance of the higher tower.
The other thing is that I've been doing site surveys for several years and I do have the average wind speed here to benefit from wind. That with my ability to inexpensively produce windmills ( I figure under $300.00 each with blades) makes wind viable for me, especially now that I have my PV in.
Microhydro will go in this summer too and this should round out my energy very well (I hope!)

Steve,
I've put up several ham antennas too. (W2IE)
Rob

Very cool. Make a build post with lots of pictures along the way. We don’t have much wind but this has always interested me.

[Robaroni]

Originally Posted by pinballlooking

Very cool. Make a build post with lots of pictures along the way. We don’t have much wind but this has always interested me.

You bet, I plan to.
Rob

[Acuario]

Where I live it's regularly very windy, I'm not that far from the windiest place in Spain - if only I had known as I hate the wind.
.
I have seen more small cheap wind turbines with blades, tail fins, nosecones missing than I can remember. Nearly everyone here that has invested in one regrets it. A couple of years ago one was installed close to me that must have cost 5000+ euros. First winds it lost 2 blades. They did repair it but now it looks like it spends more time in braking mode than in generating mode.

The problem is the turbulent air and almost continually changing directions and gusts. It destroys conventional turbines.

The only ones that seem to survive are the vertical turbines - I have yet to see a broken one. they seem ideally suited to the 'type' of wind we have here.

Personally I always advise clients to buy a couple of extra pv panels as we tend not to suffer from a deficit of sun and here when it's windy in the day 9 times out of 10 it is also sunny.

Acuario

[Servicetech]

Got Wind?

Hour-by-hour wind predictor for Thursday | KOCO Home - Weather

[pinballlooking]

Originally Posted by Acuario

Where I live it's regularly very windy, I'm not that far from the windiest place in Spain - if only I had known as I hate the wind.
.
I have seen more small cheap wind turbines with blades, tail fins, nosecones missing than I can remember. Nearly everyone here that has invested in one regrets it. A couple of years ago one was installed close to me that must have cost 5000+ euros. First winds it lost 2 blades. They did repair it but now it looks like it spends more time in braking mode than in generating mode.

The problem is the turbulent air and almost continually changing directions and gusts. It destroys conventional turbines.

The only ones that seem to survive are the vertical turbines - I have yet to see a broken one. they seem ideally suited to the 'type' of wind we have here.

Personally I always advise clients to buy a couple of extra pv panels as we tend not to suffer from a deficit of sun and here when it's windy in the day 9 times out of 10 it is also sunny.

Acuario

The wind always helps solar production. It seems to keep the panels cooler so the make more power.

[Robaroni]

Originally Posted by Acuario

Where I live it's regularly very windy, I'm not that far from the windiest place in Spain - if only I had known as I hate the wind.
.
I have seen more small cheap wind turbines with blades, tail fins, nosecones missing than I can remember. Nearly everyone here that has invested in one regrets it. A couple of years ago one was installed close to me that must have cost 5000+ euros. First winds it lost 2 blades. They did repair it but now it looks like it spends more time in braking mode than in generating mode.

The problem is the turbulent air and almost continually changing directions and gusts. It destroys conventional turbines.

The only ones that seem to survive are the vertical turbines - I have yet to see a broken one. they seem ideally suited to the 'type' of wind we have here.

Personally I always advise clients to buy a couple of extra pv panels as we tend not to suffer from a deficit of sun and here when it's windy in the day 9 times out of 10 it is also sunny.

Acuario

Acuario,
You make a good point about VAWTs (vertical turbines). The horizontal guys love to turn their noses up at VAWTs but they have some very strong points.
No yoke bearings, no furling, much sturdier, better for birds, etc. Yes, they put out less power but sometimes less power is better than a mill with broken blades!
Living in very windy places is tough, once and awhile the wind gets to be steady around here and it puts people on edge, I can't imagine what living in Northern Scotland is like!

Rob

[Robaroni]

Originally Posted by pinballlooking

The wind always helps solar production. It seems to keep the panels cooler so the make more power.

I notice this too. On windy days with a full sun I put out more power. I was wondering if the wind 'cleaned' the air up a bit?

Rob