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Microwind Generator For Low Power Systems
Posted by
CmdrTaco
on Sun Oct 14, 2007 08:06 AM
from the welcome-to-sunday dept.
from the welcome-to-sunday dept.
An anonymous reader wrote in to say that "Shawn Frayne, has developed Windbelt,
efficient, cheap lowpower wind generator built out of taut kite fabric." Everyone has seen the video where the suspension bridge is ripped apart by wind- his idea was to use the same thing to generate power. I doubt I'll be running my desktop off it any time soon, but it's a cool idea.
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Submission: Windbelt: Microwind Generator for lowpower systems by Anonymous Coward
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Macro wind power: Kite Gen (Score:5, Interesting)
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Re:Macro wind power: Kite Gen (Score:4, Insightful)
Laddermill from the Technical University of Delft is also working on it for a number of years now:
http://www.lr.tudelft.nl/live/pagina.jsp?id=8d16d19a-e942-45aa-9b52-48deb9312e92&lang=en [tudelft.nl]
Publications:
http://www.tudelft.nl/live/pagina.jsp?id=fe263f84-29af-4010-8222-2f1112c8f223&lang=en [tudelft.nl]
The more alternatives for environmentally friendly energy sources the better!
Parent
Re: (Score:3, Informative)
Traditional wind farms (using wind turbines) are apparently not much of a problem for birds. I recall a study done years ago in The Netherlands, where some environmental protection group wanted to see how much damage the wind turbines were doing. The startling result: nearly nil! The explanaition: birds will not fly into the turbines because they are warned by the noise.
Now how that would hold up with the kites I don't know. My only experience is with kiting at the beach: we could sometimes see seagulls ma
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I find it hard to see how this "kite" technology works. At such a height, any movement from the air foil would be diminished to a few degrees or less at the generator on the ground.
Check this [susx.ac.uk] paper (PDF) about neural net / genetic algorithms for steering power kites.
"The common element between current proposed traction kites applications is that
the aerodynamic forces developed by the kite are transferred via the lines to perform
work at near-ground level. This could be either the direct acceleration of large masses
such as cargo ships, or the turning of a dynamo as the taut lines slowly spool out
from a reel."
For the reel dynamo, you'd have a power generating reeling out phase, and a po
Re:Macro wind power: Kite Gen (Score:4, Informative)
Parent
Sub-100W generators are very interesting... (Score:5, Informative)
See the discussion here for example: http://www.fieldlines.com/story/2007/10/13/9445/4984 [fieldlines.com]
Much as I'm intrigued by this let's not get into perpetual motion machines nor "beating Betz" just yet! In particular the "30x as efficient as the best microturbines" claim in TFA is particularly suspect: I have a VAWT made from a cardboard cereal packet in my back garden that probably extracts 10% of the available energy.
Rgds
Damon
Re: (Score:2, Interesting)
Re:Sub-100W generators are very interesting... (Score:5, Insightful)
All thing else being considered equal, compare a modern turbine:
-Mast
-At least two (Usually three) airfoil blades (engineered composite materials)
-Gearbox (fairly complex device)
-Generator head (fairly complex device)
To this thing:
-Mast with gap in middle
-Length of strong, flexible material (metal, plastic)
-Permanent magnet
-Coils of wire
That's dead simple and could probably be supplied in kit form and assembled with absolutely minimum tools... like nothing but a large hex wrench.
=Smidge=
Parent
Re:Sub-100W generators are very interesting... (Score:4, Interesting)
Parent
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Yes, the parts are complex, but the interconnections between them are not.
'Taught' material? (Score:5, Insightful)
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Units (Score:4, Funny)
So will the power output be measured in bridges per minute?
Prior Art, 1964 (Score:2, Interesting)
And how exactly does the science work? (Score:2)
Re:And how exactly does the science work? (Score:4, Informative)
Haven't you ever made a blade of grass whistle between your thumbs?
Parent
Dupe, sortof (Score:2, Informative)
Wrong solution (Score:4, Interesting)
The only sure way to help countries of the third world is for countries like the US to open up their subsidized markets. The corn market in the US for example is subsidized to an extent of almost 10 billion dollars in 2005!
If third world countries got just half of that market, a lot of lives would be changed.
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Subsidies are necessary, you're not thinking about how the world works. A country should never let a large proportion of it's food production all be outsourced. What happens in case of war or political/trade fallout? Yeah I thought so too. Whle free-market apologists will cry "protec
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Here is the problem: When the Australians, Japanese and Europeans do exactly that, the US screams "subsidies, subsidies, subsidies...", as if the US is any innocent.
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A country should never let a large proportion of it's food production all be outsourced. What happens in case of war or political/trade fallout?
Here is the problem: When the Australians, Japanese and Europeans do exactly that, the US screams "subsidies, subsidies, subsidies...", as if the US is any innocent.
The U.S. is the bigger market, therefore it can negotiate trade agreements that are in its favor. Chances are, the Australians want access to the U.S. market a lot more badly than the U.S. wants access to Australia's; therefore, the U.S. can keep its subsidies and make other nations get rid of theirs.
Life is not fair.
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Protected industries grew; their customers failed to grow because of the higher prices. The net effect was inferior to free trade.
Re:Wrong solution (Score:5, Interesting)
I have news for you: raw industrial efficiency is not the only measure of a successful economy. How a nation's economy provides for its people, long term, is an equally important metric. I would say, a far more important one. Throwing away domestic manufacturing in favor of cheap imports from inimical foreign powers is not a good way to serve the needs of your people. In fact, free trade, so far as the United States is concerned, is doing exactly the opposite. We are transferring massive amounts of money to China in exchange for cheap imports, while simultaneously losing the ability to provide for ourselves. What good are these customers of whom you speak, when there are no longer any American producers of those products? Explain to me how this is good, how it grows our economy?
The original poster in this thread was correct: if you have any sense of self-preservation whatsoever you protect your key industries. If you don't, and someone takes them away from you (as is happening with virtually every manufacturing sector in the United States today) you are vulnerable at every level. I'm not saying that means exclude all foreign competition, but it does mean that you make damn sure that foreign competition isn't allowed to operate in a predatory manner. Unfortunately for us, our government and corporate leaders sold us out for a song. Now, I don't know exactly what's going to happen over the next few years, but if what I read about American manufacturing being down to 1950's levels is even close to being true, we are in deep shit.
This is not a joke, this is not some philosophical issue with no real-world effects: when a major economy falls people get hurt. Ours is heading for a fall of Biblical proportions, and it's you Free Traders that will bear a significant responsibility for that event.
Parent
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Re:Wrong solution (Score:4, Insightful)
Parent
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Because said Westerner knows that he can have little impact on international trade policy, but does have a potentially nifty, cheap approach to micro-generation? Don't let me stop you from looking that gift-horse in the mouth though.
Re:Wrong solution (Score:5, Insightful)
I've seen your kind of reaction turn up in the Slashdot discussions about the OLPC project. Here's a summary of what I see as being your argument:
"This is a waste of time -- a worthless solution -- because it doesn't provide the power and performance that I, as a westerner, demand from technology."
If that's an accurate summary, I have news for you: if you've spent a lifetime living on the edge of civilization, having a power source that can turn on a few LEDs at night or run a radio, or having a "worthless, underpowered laptop" can mean a real improvement in your life.
I'm sorry if this windbelt doesn't provide you with enough power to run your home's AC unit, your 62 inch plasma display, your 100+ halogen and assorted incandescent light bulbs, and that server room in your basement. The thing is, this solution isn't meant for you. I know that's hard to handle -- that someone might be thinking about people other than yourself -- but please try to accept that possibility. If you find that overly taxing, just crack open another beer and take your Hummer out for a drive to the gas station.
Believe it or not, there are people out there who can get by with a lot less than you, and for them, something like this will be a big deal.
Parent
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If you can't make large improvements that doesn't mean you can't try to make small ones. Not everyone gets to save the world, but some people can make it a slightly better place. Even though this device won't make Tanzania export leader I'm p
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That's not the biggest problem that most of the third world has, not by a long shot. Sure, they'd benefit even more than we would if our tax money wasn't spent on keeping farmers growing more of a given crop than the market wants them to, but the biggest drag on any third world country today is the local kleptocrats who hand out monopolies to their cronies, and use aid money to buy weapo
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None, huh? So why does he show the device powering a radio and a clock in the video? You're right, 40mW isn't much power, but according to the video the device costs $2-$5. For that price, you can easily build a few of them & you start to get to a more useful amount of power. But even 40mW is enough to do things like maintain the charge on a cell phone or charge a flashlight. I'm sure someone with more knowledge of low power syste
A bit more detail (Score:4, Informative)
Mod parent up (Score:2)
Some new materials tech here ... (Score:2)
Must be some kind of memory fiber that returns to its original shape when the wind stops blowing.
bridge is ripped apart by wind- (Score:2)
The wind was just the power to get it to resonate, from that point on it was all vibrations.
Dupe (Score:2)
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Yay for ingenuity! (Score:2)
If you think about it, the wind turbine is essentially based on the old windmill design that has been around for centuries. It's reasonable to think that when people people were first thinking of a way to harness wind energy, that was the first thing they thought of for that exact reason.
Not a Single Engineering Reply (Score:5, Informative)
The whole concept is interesting, because it can work with wood and cloth instead of mylar and aluminum. The "first world" part would be the magnet, coils and the DC rectifier/converter to allow a user to likely charge a battery.
How many of these generators and how big they would be to extract a usable 10 watts of charging power in a 5-10 mph wind hasn't been defined, but with a couple models, that can be determined.
You never learn anything by bitching. Buckling up and testing is the way this & other ideas will be understood and improved. For the 3rd world, just a minimal LED lamp array can make the difference between studying at night or not.
Re:Not a Single Engineering Reply (Score:4, Informative)
I am not an engineer, I do not think I could build this, but were I capable I'd try it out and start to look at the numbers.
1 - It was said it would not work in low winds (5/10 mph) because the demo used a fan. Prove it I say. it may be a combination of material tension and mass of the magnet.
2 - It was said it would buzz. Prove it. Build one and measure the decibels produced. Can the sound be dampened without losing efficiency.
3 - It was said it was not 30x efficient. Prove it. Build one and compare it to other micro wind generators (though the video indicated there were few out there)
I know this is
Parent
Another oscillating generator (Score:3, Interesting)
It's so Popular Mechanics. Another resonant oscillating generator.
This is an old idea, but the usual form is a free-piston engine. [freepistonpower.com] Popular Mechanics was hot about that one back in 2004. For something that will light two LEDs, that thing looks big and expensive. Note the machined aluminum frame. For comparison, here's a toy wind generator kit [amazon.co.uk] ("convert a plastic bottle to a wind generator!").
Notice how the guy with the vibrating ribbon generator demonstrates it in front of an electric fan. On high. That's probably because it only works in a strong wind. People generally don't live where winds are regularly that high. Wind speed in Port-au-Prince has been between 9 and 12MPH all day, so something that cuts in around 9MPH is needed for use in Haiti.
The classic cheapie generator is taking an oil drum, cutting it in half, and using that as a Savonius rotor. Then you get an alternator from a car, and there's your actual generator. The axle sticks up into the air, where the halves of the oil drum collect the wind and turn the alternator. Here's a smaller version [angelfire.com].
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http://shorterlink.org/3266 [shorterlink.org]
Or heating ductwork:
http://shorterlink.org/3267 [shorterlink.org]
As for the frame you're referring to that could easily be made of local materials like wood or recycled plastic or almost anything that will put tension on the material. And the repair on this object is considerably cheaper than replacing something like the spindle bearings of a oil-drum wind generator which will wear out over a long period of constant use.
Re:Nah, this is dumb (Score:5, Interesting)
Not too dumb. He was designing it for use in Haiti. While I suspect there are places where nothing is tenable, a thin ribbon under tension is a whole lot simpler and cheaper to manufacture and maintain than a rotating wind turbine. It doesn't have to be mylar, you could use scrap cloth, although mylar may last longer and be easier to keep under tension. LED's were for the demo. You could use the thing to run any light; or better yet charge a small battery so you have power on demand.
He made another good point in the article: If you break this you have something that a local can fix. If you break a solar panel, your stuck with a broken panel (which is trash). What he didn't mention is that this would run at night too, as opposed to a solar panel that only works during the day.
while I agree with another poster's comment that the 30x improvement in efficiency over a microturbine is probably not real, I think it's fairly interesting. Enough so that, since IAAAP (I am an applied physicist), I'm thinking about building one myself to get some numbers and see how well it scales. I know some people in Africa who might be interested in something like this...
Parent
Re:Nah, this is dumb (Score:4, Insightful)
Sure, but this will only run when there is wind. In any case you are going to need some kind of energy storage, whether batteries for small scale use, or pumped water for larger scale.
With a small scale system like this, you could also combine it with solar panels and a battery and get luggable power generation that would work in most places.
I'm thinking about building one myself to get some numbers and see how well it scales
Cool! I'm sure a lot of people would love to see a project page for a DIY wind generator of this sort!
Parent
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I got a couple of battery re-chargers for AA - C and 9 volt, and started recharging for all my flashlights, MP3 players, and such a few years ago. Last year, I rigged them to a small solar array, so those apps are now completely off the grid. I cold probably have used a very small wind turbine just as well, or an adaptation of a widget like the one in the article. With a good supply of batteries, I can
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My guess is that generators in series can't easily be synchronized, but generators in parallel would tend to self-synchonize (assuming near-identical construction and side-by-side location).