VAWT Wall

[Tritium]

Here are 4 pics of a VAWT "Wall" near Turkey TX. More info will follow as I can get it.

Thurmond

[electrondady1]

at first i thought they were oil drums

 but in comparison to the size of the trucks it would appear they are much larger.

[feral air]

I'm in awe.

The rotor shape doesn't look all that efficient but maybe that was done on purpose....if its primary purpose is as a wind break (shielding the traffic perhaps?) then a less-efficient rotor could be a good choice.

No matter how you look at it that's quite impressive.

[electrondady1]

ive always liked the three bladed drag design.

i am just guessing each is about 6x10

so 60x30 = about 900 sq. ft. swept area !!

should be just about enough lol

[healerenergy]

I like to see things progressing towards more awareness of better things.

George

[PHinker]

   It looks like the individual units are independent.  Also, the shafts at the bottom don't look nearly heavy enough to take power from a column.  Is this just some sort of 'moving art'?  Considering the swept area, even at low efficiency those two panels are going to capture a fair amount of power.

[Tritium]

No art this is a commercial venture with investors and green certs.

From what I am able to gather from very sketchy information it seems to me that they are using the turbines to generate hydrogen and oxygen then probably using a chinese fuel cell to feed the grid. It is not working yet though and they just brought a expert from china to tweek the system. Rumors indicate that he was caught by US authorities with a lecture bottle of H2 in his luggage. He is currently the guest of the Homeland Security people.

Thurmond

[TomW]

As noted by someone above, I have to ask "where are the alternator located? Probably just art but could push a few watts of power even in a low wind.

Looks cool anyway.

Cheers.

TomW

[Tritium]

Next time I am up that way I'll take a side trip and colllect more information cause the entire thing sounds fishy to me as a commercial venture with 14 employees currently.

Thurmond

[bob g]

i don't think there is a way on earth that thing will harvest any real amount of power,,, the shear area of that thing will produce an enormous torque on the mounting system.

if they try to load it down, the first 30mph wind is going to lay it flat!

i can't imagine that the hiway dept would allow something like this to be erected so close to the road way.

looks a bit scarey to me

bob g

[TomW]

bob;

Yes, it looks a bit under built to bulldog any wind.

Maybe it is "highly engineered"?

Should get the resident vawt guys going, tho.

Cheers.

TomW

[feral air]

Look at the beams. It's really hard to tell but they look like 8"x8" or better.

The back braces are kind of interesting to me too. I would've put braces in both directions, just in case. Especially since if they topple over they're basically in the road. As far as I can tell that seems to be the weakest link.

The shafts hanging from the bottom should be plenty big enough to pull power from. There's some torque to vawts but not that much - usually the torque slowly increases, it doesn't just jump from nothing to insane levels. The fact that you can see the shafts in the photo suggests to me that they're as big around as a manly thumb.

I dunno, it sure looks impressive though...just the size of the things.

[TomW]

feral;

One thing I see as curious, also is the buckets seem to "line up" top to bottom. Seems that they would want them offset a bit to get past torque ripple effects and ensure startup from any rest position.

Not being a mechanical engineer I may be missing something but I can pick out a half dozen things in that array that look a bit under thought out to me. I won't but it just does not seem feasible from here but somebody bought in to the design apparently.

I can just see that rolling off across the prairie and killing a couple folks and then legislation restricting wind turbines in general.

Just a couple of the many thoughts I have on it.

Cheers.

TomW.

[PHinker]

   Right, that's why I thought the individual cells must be independent because it looked like they were neither all lined up nor offset by a regular amount along a column.

   What's the size of a 'manly thumb'?  My thumb is about 1 1/8 inches across but a shaft that size wouldn't be large enough if you connect an alternator/generator to the column.  Seems like they'll twist like a licorice whip.

   I agree with the comments about the nearness to the road.

[boB]

Hey !  they can't do this !  They're going to block all of

my wind !

[Tritium]

Bear in mind that this is an early shot from a few months ago so they may be cabled or braced better now. They were building many of these. Each stack of "rotors" are on 1 shaft with a generator at the bottom of each column. I will probably be in that area in the next couple of weeks so I will get new pics and try to see about talking to the owner of the project for more details.

Thurmond

[scorman]

here are some specs:

http://www.windoptions.com/projects.php

some pricing details:

http://www.windoptions.com/pricing.php

Stew Corman from sunny Endicott

[ghurd]

I think the (unconnected) buckets would naturally line up. Eventually. Loaded or not.

I do wonder where the alternators will be.

G-

[feral air]

1 1/8 inches across is a pretty manly PHinker...I mean thumb. ;-)

Since this is a commercial venture I can almost garauntee that they know the shear strength of the shaft and that they have a pretty good idea of the power those vawts will produce.

Think about what kind of components are in your car and what kind of torque it produces. I doubt 3 of those rotors produces anything like what's under the hood of a geo metro let alone anything with oomph, except maybe in hurricane-level storm winds.

I'm not a mechanical or structural engineer either but I've got a good gut and my intuition rarely fails me. Of course I could be wrong (and I'm not afraid to admit it when I am) but the shaft looks fine to me, especially since their rotor shape looks so inefficient.

All we have is the photos until Tritium makes a trip back out that way so I'm reserving my final judgement. All I can say for certain is that their size is impressive.

[vawtman]

Thurmond,

 Of all the things vawts can do i never thought billboards was one.Cool post.

 Mark

[electrondady1]

way to go tritium !

charge up your camera batteries and see what else you can find out

thanks for the post and links

 each "unit" is 64 sq. ft. those two billboards =1920 sq ft swept area.

[Ungrounded Lightning Rod]

The shafts hanging from the bottom should be plenty big enough to pull power from. There's some torque to vawts but not that much - usually the torque slowly increases, it doesn't just jump from nothing to insane levels. The fact that you can see the shafts in the photo suggests to me that they're as big around as a manly thumb.

If I'm reading the specs right each shaft is expected to produce about 2KW at the 8MPH cutin and a smidgeon over 10KW in a 35 MPH wind.  10 KW is between 13 and 14 HP and assuming 66% efficiency you're taking 20 Brake HP on the shaft.

The individual rotors seem to be about 10' tall by 8' wide.  From a 4' radius and assuming a TSR of 0.8 it should be simple to compute RPM and combine that with the BHP to get the torque.  (Can't spend the time to do that now.  Maybe somebody else will?)

Presuming the RPM is comparable to an auto drive shaft that handles 200 BHP with ease, something a third that radius (1/sqrt(10) is .316...) would handle 20 BHP with the same ease.

[Ungrounded Lightning Rod]

One thing I see as curious, also is the buckets seem to "line up" top to bottom. Seems that they would want them offset a bit to get past torque ripple effects and ensure startup from any rest position.

Looks to me like they're offset 1/9th turn as you go down, which is right for a 3-bladed rotor.

Also looks to me that each shaft's rotors are lined up with those of each other shaft - and at the same position on the second unit, too.  From this I presume they've got them bolted down to the frame while erecting the structure.

[Ungrounded Lightning Rod]

Also looks to me that each shaft's rotors are lined up with those of each other shaft - and at the same position on the second unit, too.

Correction:  The left one has all the shafts in the same position but the right one has them each at some random position.

[CmeBREW]

Now thats COOL! I think TOM hit the nail on the head---Man, I'm going to start building one just like it tomorrow!! (40 oil drums and a BUNCH of 2x4's!)  I hope my neighbors won't think it's an 'eye-sore' or anything like that.  -ThanksThurmond.

[jimjjnn]

What happens when the wind comes from the side? It seems that the wind "shadow" from the turbine in front would block the wind from other turbines. I am assuming tho that they are facing prevailing wind so that the shadow effect would be minimal.

[KEG]

Did someone say the E word in here ?

shame on you

Remember size doe's matter !

LOL

[boB]

>>What happens when the wind comes from the side?

Oh NO !!  Mention that to them and maybe they'll put a tail and a pivot on it so the whole dang wall can rotate into the wind !  Better duck....  No, better learn to limbo !  How low can you go...

boB

[ruddycrazy]

Eh Cmebew,

           In a strong wind 2x4's will fail with an all mighty bang. If your going to make a similar one i'd suggest as a mimuim 150x150x8mm RHS as the frame 'heavy duty steel'. Hopefully we'll see the finished design with alt's attached as this type of struture intriges me. I can just imagine when the power guys come on my farm if decide to make a smaller design and ask what in the hell is that and I tell them its a 10Kw genny to heat our swimming dam

Cheers Bryan always ruddycrazy

[Gary D]

Tom, went to their link and each drum set is 3 bladed. It's a class 4 wind site. Hope they ran the footers and steel 15 feet deep like they do for road signs/ billboards down there.... They are planning to erect quite a few (3000) so they will need the 14 or so people full time! Wonder how many times they will need to stop during lightning storms tho...

 At $30,000 per stack, inverter not included, hope someone has very deep pockets! Lots of stacks in just that one array...

[CmeBREW]

I was just joking after what TOM said "that this would get the VAWT guys going"!!

I would never make that! I had been thinking about a "Wall of VAWTS" though, using long Pieces of PVC pipe (halves as usual)  hooked together at the bottom--with sprokets and chain to add up the torque for one generator at the end. But after seeing the price of that 6" pvc at the store, I changed my mind. I also can't seem to find any 'thin wall' 6" drain pipe anywhere around here. I think I am finished with the PVC Vawts! Not enough torque to mess with. I am now seriously leaning toward making a BIG 7' high "Squirrel cage" VAWT for the corner of my house. It should have nice torque,speed,AND self-regulate in high winds. (hoping!)  

[chadking]

Great pics!  It will be interesting to see how those walls finish up, etc.

The closest thing I've seen to this before were these guys in MA doing some towers like that, each with two walls of rotors...

http://www.massmegawatts.com/

I don't know if either method is efficient for the construction/maintenance costs, but putting that many rotors up in the wind should make some kind of power.

[bob g]

i don't know about the rest of you guys

but i am keepin my investment money in my pocket,, deep in my pocket!

bob g