vawt, a curious phenomenon

[electrondady1]

so many posters express interest in constructing a vawt

and yet so few make any progress to wards completion.

 

[DanG]

Ward is building a VAWT?

[Norm]

VAWTs are neat to look at but most people

can make a hawt pinwheel quicker than they

can make a foam cup savonius.

Both look neat spinning in the wind !

[fungus]

Just a little taster .. if you can see what I've put it on, that'll be chopped up for a frame to hold it in with a top bearing

[gotwind2]

I'm intriqued by that picture Fungus,I was wondering what had happened to the rewound Ametek - Nice easter holidays project - it must be nice for some people

It will be interesting to see what power it can achieve.

Ben.

[Stonebrain]

Be patient,I'm working on a new design,the ultimate vawt is coming.

cheers,

stonebrain

[TomW]

If I had just $0.25 for every time thats been implied, I could buy a Bergey.

I will await your breakthrough with a check ready to invest.

Tom

[Bruce S]

From what I've seen here on the board, even back when there was ton of interest in the 3 bladed VAWT; I believe I even remarked back then that it looked like a set of duck heads :-] while looking down at the paper printout, that they are actually an easy way for people who are looking to copy the successes that Mother Earth News had back in the 70 ~ 80s.

Using big metal drums and welding stuff you could put one up that will indeed work, however, there's the space that it needs to be up for anything that can be a constant source of charging. M.E.N. did that with no problems.

Now, though , there is the need to get as much out of what you can as possible. The early Otherpower forum had lots of stuff using the ceramic magnets , now since the newer ones work so much better those hardly get any mention, but are still good .

Once someone gets their feet wet form trying or completing one and then get "hooked" on the POWER :-) they normally jump to the more powerful HAWTs.

Curiously enough, the city, in an area like where I live, are more likely to allow VAWTs, like the one fungus has up than they would a HAWT any day.

VAWTs are normally slow moving and are there for looked at as Lawn Art or safer with less room needed to keep things safe.

For small units VAWTs look to be even easier to bulid Windstuff Ed's learner kits is a beautiful kit and a prime example.

I certainly would not count it out, have a look at Pepa's unit.

JMHO:-)

Milage my vary...

Cheers

Bruce S

 

[Bruce S]

A true beauty:-)

Did you powder coat that?

Bruce S

[Stonebrain]

That's great,

With the 100$ from volvofarmer (sure my rotor will be a winner)and your check I get really motivated to speed up the work.

Still so much to do and so little time available and I'm working so slow.Desperately trying to keep up with the ideas that are coming up.

...sigh..

Promise to put some photos on the progress in my diary.

Cannot keep it for myself.

cheers,

stonebrain

[gizmo]

Is it been sugested that the VAWT builders should give up? Stick with the proven HAWT axial flux design? I mean, why bother trying something new, it will probably fail.

The way I see it, in clean wind a HAWT wins hands down. And a VAWT with a tail is kind of pointless. But in crap wind ( ie, suburbia ), a omnidirectional VAWT can work and is working for a lot of builders. Besides, they look cool

Glenn

[wdyasq]

"Is it been sugested that the VAWT builders should give up? Stick with the proven HAWT axial flux design? I mean, why bother trying something new, it will probably fail."

I get occasional flack because I tell folks there has been little or no VAWT success. I usually suggested one do the research and not repeat past mistakes.

Sandia Labs did considerable research on VAWTs. If one is planning on building a VAWT and does not at least read what Sandia Labs did and what problems they encountered and how they attempted to solve them, they are probably wasting their own money. Quite possible the US government, through an agency, has already wasted a lot more money on the same thing .... and written a report on it.

At one time or another, I read many of the reports. They are not encouraging for a VAWT builder. Personally, I don't have the money to make all of the mistakes a government agency can and has. One can only surmise the VAWT advocates must be independently wealthy as they ignore the advice and bow-up like a puff-adder.

My advice to a VAWT builder would be to (after reading all possible) build what they desire. Put a 'Prony brake' on it. Get some good readings. Then come to this board and say. "I've got a device producing X torque at Y rpm. I need to design an alternator for it." They might also supply a picture to the curious and non-readers of the board. Of course, I highly recommend of one has such a device in the form of a VAWT they might consider a patent. The cost of a patent would be 'chicken feed' to one who can afford to ignore past art.

Ron

[gizmo]

I agree with you Ron, like I said in clean wind a HAWT cant be beaten, because of its combination of efficiency and ease of manufacture. Designs like the Lenz2 make may power comparable to a similar sized HAWT, but they are a lot harder to make.  And a VAWT that needs a tail is a waste of time because it cant compete against a proven HAWT.

But for a lot of the visitors to this site, a HAWT in clean wind is not an option. Most of the VAWTs we see here are in back yards, where the wind changes direction every few seconds and a HAWT will perform dismally compared to a VAWT. I've had a Lenz2 and a standard 3 blade HAWT up on the same mast for different times of the year, and for the winter months the Lenz2 out performed the HAWT, simply because it could use the turbulent winds better.

The point I was trying to make is the anti-VAWT comments on this board are not helpfull, in fact its down right depressing to read them. As soon as someone suggests they are building a VAWT they are bombarded with negative comments, not constructive comments. VAWT's have a place, they are great teachers, fun to make and cool to look at, even if they dont perform like a HAWT out in the open. Yes most of the VAWT's wont perform as well as the builder hoped, but thats the fun bit, building something and learning from the exercise.

Glenn  

[Volvo farmer]

If you truly have a VAWT in the wind, making power, I would strongly urge you to post a story about it here. Perhaps you already have and I missed it? I would also be very interested in reading on the VAWT vs HAWT in your backyard comparison, perhaps some amp or amp-hour readings? Pictures? Details?

The reason I am against VAWTs is that most people say they want electricity out of them. I have been watching this board pretty closely for a while now, and with the exception of Ed, have not seen a single reported VAWT constructed that will make more than a few watts of electricity.

My goal is to keep some new person, whose goal is making electricity they can use, from wasting a bunch of time and resources. As far as I'm concerned, VAWTs are basically vaporware. I've seen exactly one reported success on this board in all the years I have been reading.

So I would argue that perhaps the anti-VAWT comments are helpful, if given in the right circumstance. It's an open board, maybe you could speak up and give these new users a template for a successful VAWT, as you seem to have built one. Until I see some modicum of success though, I will continue to view them as vaporware.

If someone comes in here says they want a fun project, or something cool to look at, or a learning experience building a VAWT, my mouth will remain shut. However if they are looking for watts, and do not seem to understand the pitfalls, I will continue to discourage them from building a VAWT.

[Bruce S]

Gizmo;

   I'm curious about the toothed one you had up on your website. How's that one coming along.?

Bruce S

[electrondady1]

 just want to say i am delighted  with the tone this thread has taken.

 and i'm  in complete agreement with all the opinions voiced.

  a suburban niche exists and vawtes seem best suited to fill it.

there seems to be less difficulty in constructing the spinney bits

than in properly matching them to an alternator.

i think that's were most novice builders run into difficulty and abandon

there projects.

i think it may be helpful if we could discuss how the design of a vawt alternator

might  differ from the typical hawt alternators  that have become so successful here.

 

[gizmo]

Some links to the Lenz2 windmill.

http://www.thebackshed.com/Windmill/FORUM1/forum_posts.asp?TID=497&KW=lenz2

http://www.thebackshed.com/Windmill/photos4.asp

http://www.thebackshed.com/Windmill/PumpControler.asp

http://www.thebackshed.com/Windmill/FORUM1/search.asp?KW=lenz2&SM=1&SI=PT&FM=0&OB=1

http://au.youtube.com/watch?v=CCfEq851cxs

The Lenz2 spent some time as a water pump, before ending up on the tower last year for several months. I think the most I ever saw was 60 watts into 12 volts. Not much, but fact is the 6 foot HAWT it replaced was making NOTHING! Watt Hours, the Lenz2 kicked butt. The Lenz was only small, 1300*1200mm. I had started to build a  bigger one thats 1800*2400, but its in the list of half finished projects for now, cost of the aluminium skin was too much at the time to complete the job.

But, in Summer, when the winds are from the North, I put up the HAWT, as it works better in the clean winds. Thats my point, a VAWT has a place, and under certain conditions it can out perform a HAWT.

Glenn

[gizmo]

Your dead right on that electrondady1. I think the VAWTs attract interrest cause they seam easier to make, but fact is, they are a nightmare compared to a HAWT. The problems I found are tower wobble, the shear weight of the things, and whats the best material to cover the wings with.

Glenn

[gizmo]

Do you mean the little cyclonturbine thingy with the tail?

It worked, but like I said I dont see the point of a VAWT with a tail. Was fun to make and watch, lots of moving parts though and needed to be oiled every couple of weeks. Wouldn't make another one.

Glenn

[thefinis]

One problem/advantage with vawts is that there are so many types out there. H rotor, S  rotor, eggbeater, helix, combo designs lift/drag like a lenz or a high lift H rotor with a drag S rotor starter. A hawt has many versions too but most are lift based. A turbine needs to fit your needs, skills, and materials available. As Gizmo pointed out many folks when looking around feel that the vawt is the easiest to build but weight, materials, reality and rpm matching tend to slow the builders to a point that many never finish. This may hold true for hawt builders too as they work towards a finished product goal.

Personally I have made many vawt turbines but never made one that I was willing to hook up to make electric power yet. Most either didn't make enough power to follow through on or were constructed for testing and were not sturdy enough to attach to a suitable generator and transmission. I did find that while vawts work in gusty turbulent flow the power seemed to be reduced by more than I expected. Wind speed cubed bites on extracting power as average wind speed drops. You have to get above the trees. The next project is to put some up on a tower in cleaner air.

Finis

[feral air]

I've got a new half-secret plan but I'm gonna spend some more time on it before I share. I kind of want to see for myself if it really works or not, if it makes any sense. I've got some stuff to build and referb yet...

Don't worry, I'll save you guys from having to hear about it for a while longer. take it easy