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Vertical Axis Wind Turbine With Push and Pull
Sterling D. Allan writes "After 10 years of prototyping, wind tunnel testing, patenting, and tweaking, Ron Taylor of Cheyenne (windy) Wyoming is ready to take his vertical axis wind turbine into commercial production. Design creates pull on the back side contributing to 40%+ wind conversion efficiencies. Because it spins at wind speed, it doesn't kill birds, and it runs more quietly. It also doesn't need to be installed as high, and it can withstand significantly higher winds (can generate in winds up to 70 mph, compared to ~54 mph tops for propeller designs). Generating costs estimated at 2.5 cents per kilowatt-hour, putting it in the lead pocket-book-wise not just of wind and solar, but of conventional power as well. Production prototype completion expected in 5-7 months."
...but I don't take anything "Open Source Energy News" posts seriously anymore. It seems like every post that comes from them is a crackpot.
While vertical axis wind generators aren't new - the Soviets utilized vertical designs for the most part - this design is. Wind power usually isn't practical or environmental for large-scale deployment (land usage/kW is too high), and I expect this design won't change that, but it could make wind an even better choice for microgrids.
Shame the article reads like Yet Another Slashvertisment (someone wants venture capital I guess) - I'd like some more details.
From: http://www.windside.com/
"Windside works, when others don't, with gentle summer breeze and in a violent winter storm. It works, when others are in deep frost. Windside produces electricity at least 50 % more in a year than traditional propeller models. All the year round. Many things make it extraordinary. And therefore it gives the best value for the money."
Not sure what the differences might be. Winside apparently has been producing these vertical axis windmills for extreme environments for, they say, about twenty years. But they do seem costly. They use a helix type design for the blades, see: http://www.windside.com/products.html
A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
And it's all... horseshit.
/. crowd, by pulling us all in to wow at the latest, greatest power generation technique that's going to revolutionize our world.
5 58, or http://www.windstuffnow.com/main/vawt.htm.
What he's proposing is a Savonius windmill. A fancy aenometer. Which we already do much, much better with the Darrius approach. The maximum possible energy that we can get out of the wind is 59%. Savonius windmills are far, far less efficient, as they rely on drag, and not lift.
Of course, he claims that it works off of lift, which-- if his mill even exists in reality-- it probably does, but the fact that it only gets "a little" boost from lift means that it is almost completely drag based.
One problem that people have when visualizing a windmill is the question, "Why not do it like a paddle-wheel? Like on an old steam-boat?" Well, do you still see those old steam-boats tooling up the river and across the ocean. No? Maybe you should wondered why. It's because... surprise, surprise, it's less efficient.
Not to mention the ridiculous claims about hurricane/tornado proof design. And the centripital forces it's have to undergo at these speeds. (Real VAWTs tend to be able to spin at such high speeds that they are explosively dangerous.) And the torque exerted on the bearing coupling of a several story high building when there's 150mph of wind pressing on the top.
opensourceenergy.com seems to be nothing more than a shrewd attempt to make fun of the
For some real information on VAWTs, check out otherpower.com. For instance, http://www.fieldlines.com/story/2005/10/7/63930/5
www.eissq.com/BandP.html Ball and Plate System. Amuse your friends. Crush your enemies.
I'll be honest, I really have to wonder about the whole windmills-killing-birds business. It always gets dragged up, but does anyone really know how many birds those propellers actually kill? I'm willing to bet it's very low; I also suspect way more birds are killed by flying into vehicles on the highway, or into the sides of highrise buildings (I had one kamikaze into my house last week, and that's not even a high rise).
The whole bird thing sounds like a convenient excuse invented by people who really oppose windmills because of noise or land use issues, but want a fuzzier, more PR-friendly excuse. The kill zone on a windmill is basically going to be the circle described by the rotor tips as they go through the air, so it's not a huge zone (as you get towards the center they're not moving as fast, tangentially) and at any given time it's not as if just flying into that ring would result in death, you'd have to be at a point at the particular moment in time when the blade moved through it. Last time I checked, birds don't hover, so you have two moving objects that would have to compete against some long odds to end up in the same place at the same time. Also, the turbines are noisy as hell -- something which is a legitimate criticism -- and I find it hard to imagine that birds wouldn't be scared off by the sound, air currents, and motion. (Actually they wouldn't make a bad large-scale scarecrow over farmland...)
Call me overly cynical but I find that particular objection dubious.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
A lot of it has to do with materials. VAWTs suffer from two notable stresses that are inexistant on HAWTs. 1) centripital forces and 2) vibration.
1) These things spin *quickly*. Far faster than the windspeed. Now, that's not so much a problem in a propeller blade because all the mass is on the inside and the blade happens to be strongest here, too. But on a VAWT, all the mass is on the outside, meaning that there is a significant amount of energy stored as they spin round and round. This pull can quickly destroy the windmill, and apparently has caused a couple deaths (Or so I have read in the windmill forums. Caveat reader.).
2) Because of the way the VAWTs spin, the mill is subject to pulsing as the blades change their angle of attack and speed with respect to the wind. Of course, this is reduced by having more blades which are thinner, (the ideal propeller being made out of an infinite number of infinitely thin blades) but the materials have limits and it seems that 2, 3, and 4 blades are all we can reasonably do. So the pulsing motion fatigues the support and can lead to failure.
HAWTs don't suffer from these problems, although they do have other problems-- such as torque applied by gyroscopic precession, torque applied by higher windspeeds at the top of the mill than at the bottom, orientation into the wind-- but they don't seem to be as difficult to overcome as the VAWT ones.
www.eissq.com/BandP.html Ball and Plate System. Amuse your friends. Crush your enemies.
Hi,
I was at the UK national Bat conference this years and there were a couple of presentations on bat kills around wind turbines. It turns out that the strange noised attrach insects and therefore bats. Certain wind farms in the use, I forget which, are on migration paths for bats. There is a suggestion that they turn off the wind turbines come migration session.
Since bats are a key part of bug control, particularly in the US, you might want to think about protecting them,
Lonely
This is the third post I recall by Stirling D. Allan recently, the others being
The first in that list featured complete crackpot pseudoscience. The second seems to be of dubious scientific merit. A quick look at Mr. Allan's website shows they are involved with a number of other areas of pseudoscience (or to put it less kindly, scientific hoaxes) such as "magnet motors" and "zero point energy" (as an energy source). That together with the two other submissions he's made leads me to doubt the validity of the information in these "stories". The main problem, however, is that these are not balanced informative articles, but rather they seem to be little more than ads seeking venture capital. Furthermore, it looks like Slashdot is soon to become little more than a mouthpiece for opensourceenergy.org at this rate.
"You call it a new way of thinking; I call it regression to ignorance!" -- Operation Ivy
it scales vertically. we built one with 6 55 gallon drums. 3 on the lower tier 3 on the upper tier cut in a way to have 6 blades per tier. all attached to the central shaft using a thrust bearing at the top and botton and then to a pulley that turns the rotor on a home built alternator at 3 times the rpm that the windmill is spinning at.
works great. put another next to it and now I get 2X the power generating capacity. add 3 I get 3 times the power generating capacity. that's the neat part 1 windmill does not slow down all the wind and scaling up works perfectly when you think of it in a multiples instead of one giant windmill.
a small village trying to be seld sustaining could create a farm of these and generate power. wind is not the only source you need, you have to couple it with solar. because the days it's not windy it's usually very sunny. and all of it needsto go into a storage system.
Typically simpler = better. because you can make more of them to compensate for the lack of efficiency that highly complex may or may not give you.
that's the problem with alternative energy, too many people make it complex as hell and scares the realy users away from it. Anyone can create a hang out your window solar heat collector that works fantastically well for about $19.00 in parts and a little time gluing, nailing and painting. But you only see the hyper expensive requires engineers to install systems advertised or talked about. same as solar electricity. you can buy your solar cells for pretty darn cheap, you do not have to pay $5000.00 per panel for new state of the art stuff.
Same as you do not need to be a aeronautical engineer and able to carve an airfoil propeller to make a good working windmill.
Do not look at laser with remaining good eye.