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floodrod
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Joined: 08/07/2009
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Posts: 70

Posted: 03:34pm 31 Aug 2009

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Hi Gang,

My F&P is almost ready and I have my charge controller and battery in hand. So now I am digging into the tower and mounting ideas.

Here's some pics of the F&P Turbine

Since my town requires 125% of the tower height between property lines and occupied buildings, the hardest part is locating the tower far enough from my own house with regards to future building plans.

So when this is worked in, I have an allowable height of around 50' measured from ground to the top of the prop. A 40' tower puts me peeking out of the trees, but not totally clearing all of them. This will have to do.

Guy wires will be difficult because they will be deep in the woods where machinery can not go, and guys will have to dodge an EPA required runoff.. So I am looking at free standing..

It seems free standing wind turbine towers are hard to find. I could only find 1 US dealer who advertises a tower with these ratings.

How do I calculate the thrust force and swept area and compare tat to the tower's specs? For instance, if I have a 3' blade setup, I have 28.3 FT swept area. What ratings in a tower will be adequate?

The Trylon Titans look pretty sturdy http://www.tessco.com/products/displayProductInfo.do?sku=470 784&eventPage=1 and it's within my budget when I calculate 10 yards of concrete trucked in, permits costs, and backhoe expenses.

But I know it's not as easy as comparing antenna dimensions to swept area. Any links or suggestions?

Edited by floodrod 2009-09-02

Gizmo

Admin Group

Joined: 05/06/2004
Location: Australia
Posts: 5119

Posted: 12:01am 01 Sep 2009

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Hi Floodrod, nice looking build.

I guess free standing towers are less common because they have a lot more steel in them compared to guyed towers, and this means they cost more.

Have a look at this thread, is discusses the forces applied to the tower.
http://www.thebackshed.com/windmill/forum1/forum_posts.asp?T ID=252

Glenn

The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ

GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 01:36am 01 Sep 2009

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Just a note here floodrod. The bolts holding the blades appear to only have star washers. You may consider drilling the bolts and using tie wires, or using Nyloc nuts. Those metal blades will work on the fixings and probably undo the nuts with star washers. I saw a wooden blade go 80m. I think those metal blades would have more energy. Don't give the council a reason to make windmill permits harder to get.

Gordon.

become more energy aware

Smart Drives

Senior Member

Joined: 06/07/2009
Location: Australia
Posts: 115

Posted: 02:53am 02 Sep 2009

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For a 14m free standing pole i would say a minimum of 200mm dia x 6mm gal pipe joined to a 100mm x 6mm gal pipe(slipped down approx 1m inside). You can do a pier footing (400-500mm dia) approx ?m deep or a pad footing . Best to find a friend who is a structural engineer to work it out. I am surprised the council haven''t said they want to see an engineers report anyway ? Normally you would have a special mix of concrete too. 12mm - 16mm thick threaded rod 600mm minimum into the footing. 20mm Base plate welded with gussets and the cage for your concrete of course.

Actually if you put 4 stays 75mm dia gal welded or bolted from about 3m up the pole and angled down at 30 degrees , you could concrete those in and that would make the size of your footing smaller ?

Just an idea, cant wait to see the finished product.

PS: that base plate i mentioned would have a mother of a hinge so you could lift it up and down.

PSS: If you could slide the internal 100mm pole up and down inside it make it a lot easier to raise and lower the turbine. Which will be inevitable.
Edited by Smart Drives 2009-09-03

All smart drive parts sold
Custom built turbine parts on
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