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Microwind Generator For Low Power Systems
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.
And now for a really interesting renewable energy concept: kite gen. Would have made Newton smile :)
They who would give up an essential liberty for temporary security, deserve neither liberty or security - Ben Franklin
Could jogging appearal be made for the tin foil cap people?
WWPD - What Would Picard Do?
...but it is not at all clear what their efficiency or $/Watt or manufacturing cost will be. Although absolute efficiency is maybe not critical for many applications given that the wind is free, cost is important in, for example, third-world deployments.
See the discussion here for example: http://www.fieldlines.com/story/2007/10/13/9445/4984
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
http://m.earth.org.uk/
What did they teach it? Um, Editors, I think the word you're looking for is 'taut'.
You can learn a lot about a person if you just take the time to inject them with sodium pentathol
I recently was looking at microturbines for my urban house recently and decided it was a bad idea because of the noise they make when the wind isnt going fast and people are trying to sleep - woosh...woosh...woosh...woosh...
I wonder if this makes a noise. buzzzzzzzzzzzzzzzzzzzzzzzzz
I have decided to use these instead of microturbines and added a pivot and tail so it can turn with the wind direction, and put 20 up on my roof. Would be interesting to see how the buzz multiplies. Would I be living under a swarm of bees?
So will the power output be measured in bridges per minute?
(In fiction at least) The Subways Of Tazoo, Colin Kapp, 1964. In the story, it was strings rather than ribbons. The story involves an alien race that killed themselves by climate change. Tsk, what science-fiction twaddle!
One line blog. I hear that they're called Twitters now.
Could someone explain the science behind this? I remember from high school physics that the collapse of the Tacoma Narrows Bridge was used as an example of forced resonance, but now I see from the Wikipedia article that resonance has nothing to do with it, and that complicated aerodynamics come in to play. Are there any experts out there who could conjecture on how the Windbelt actually works and explain it in terms of the bridge collapse?
Phoenix, Boston, Little Rock, see a pattern?
This turbine was one of the items mentioned few days ago on Slashdot in another post. See: http://science.slashdot.org/article.pl?sid=07/10/11/212243
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.
Shawn Frayne's Windbelt Wins Popular Mechanics 2007 Breakthrough Award
One line blog. I hear that they're called Twitters now.
Exactly. It's a good thing to ship these to our struggling bros, but I'm installing an ARRAY in my backyard. Here in the armpit of the San Joaquin delta, the wind is very adequate and reliable.
The cost of that cleanup, of course, will be borne by taxpayers, not industry.
From the summary: taught kite fabric.
Must be some kind of memory fiber that returns to its original shape when the wind stops blowing.
The higher the technology, the sharper that two-edged sword.
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...
On a windy day you won't have to crank your computer!
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
It wasn't just the wind, it was also the resonance of the poorly designed structure.
The wind was just the power to get it to resonate, from that point on it was all vibrations.
---- Booth was a patriot ----
This was just posted on Thursday.
"Flamebait"? This should be "Informative".
How can a post be modded "overrated" or "underrated" when it hasn't been rated yet?
This right here is what science and inventing is all about. Forget how things have been done in the past and come up with something better.
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.
Technoli
There was not any engineering detail to go on from the video, I agree. But trashing the idea without getting the numbers is bad science, more akin to the nightly news.
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.
You are thinking too in the box when you think a pet project can't go and help third world countries. It all must start with a small idea first. How do you think the XO-laptop was developed? I'm sure it started with a really simple mockup prototype at the earliest stages, a "pet project".
It all starts with some dude tinkering in his garage, in his office playing with components. Then you go to the engineering/R and D level which applies the PRINCIPLES of the pet project onto a larger scale. Not the same little toy, but the same concepts shown in the toy. Once a device has been built that captures the same principles at a much larger level, it then can be sent to third world countries. Solar panels started out as a "pet project" in some scientist's lab in the middle of the 20th century. They're now being sent all around third world countries to run water pumps to help villages get water, run Buddhist monasteries in the Himalayas, etc...
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.
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!
This has actually given me an idea to see if the same basic principle can be applied to a denser medium, ie water.
Seven puppies were harmed during the making of this post.
Huh!? What d'ya think?
Great, provided we can store the energy and use it to electrocute the winner. In the name of preventing global warming, of course.
Seven puppies were harmed during the making of this post.
Hear, hear! Well said, AC.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
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).
Contribute to civilization: ari.aynrand.org/donate
RTFA. The claim is that turbines don't scale down very well, which they don't. 30x efficiency over a turbine that generates the same (very small) amount of power isn't an unreasonable claim at all.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
First off, i only heard claims of 10x more efficient in the demo video, but i may have missed 30x in the article somewhere. honestly though, if the device costs what he claimed it did (3-5$) and it can power a small radio. (it puts out enough power to replace a couple double A's) then its a useful device. as i understand it, its not a 10x more efficient in terms of wind energy converted to power, its 10x more cost efficient in terms of being able to power small devices for x number of $ invested. to make a turbine wind generator that is useful on any level for even 10$, is a VERY daunting task, if not impossible. This defiantly won't solve the world's energy problems, but it has lots of potential uses. someone mentioned AC to DC. in the video, he talked about "costs a quarter" power conditioners, and we saw the device power a clock and a radio, which both use DC. i appears he has solved that problem. this device is literally, a 5$ wind battery, provided the article/video was not just blowing smoke.
I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.
It's so Popular Mechanics. Another resonant oscillating generator.
This is an old idea, but the usual form is a free-piston engine. 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 ("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.
-- I ignore anonymous replies to my comments and postings.
"but now I see from the Wikipedia article that resonance has nothing to do with it"
Did you read the whole article, because you seem to have missed this part,
"The wind-induced collapse occurred on November 7, 1940 at 11:00 AM(Pacific time), due partially to a physical phenomenon known as mechanical resonance."
I only go to buffets for the unlimited soft serve.
Why doesn't he use the same source of power that's running the fan?
Common sense isn't so common, is it?
I'm not saying that this is the greatest thing since sliced bread, BUT... Those who think a thing to be impossible should shut up and get out of the way of those who are doing it. You can waste your time cursing the darkness, but it's probably not going to be as productive as trying to light a candle. Or an LED.
Looks interesting, but it makes me skeptical when no real data is given. I'd be more interested in see him hook it to a multimeter and test it out at different wind speeds. Or put it outside and measure the output for a week.
You, and other posters, are right, however, that he's completely and utterly wrong.
You could use the thing to run any light; or better yet charge a small battery so you have power on demand.
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 afford to wait a bit for a sunny day, so solar's what I went with. I doubt I'm saving the environment much, if at all, given manufacturing costs of the devices, but I keep seeing the whole idea dismissed on the basis of that one argument about ecological fitness, or related argeuments about scaling.
Meanwhile, if the local power grid goes down for a day or three, I have some things which will still run, including a bit of light and an emergency radio.
It's like another, 1,000 year older tech adaptation. I also have a fireplace in my house. I don't heat with it on any regular basis, but I have a hinge mounted, cast iron widget with a hook on the end that can swing over the fire, so I can cook over it pretty expediously. The fireplace is never going to be an energy efficient way of routine heating for millions of people now using gas or electric heat. It doesn't fix any of the current problems related to old infrastructure, global warming, and overpopulation. Scaling arguments are actually negative (if we all go back to burning wood, we'll screw up the environment more, not less), but my fireplace will keep a few people warm or a very cold night without power, and even give them some hot soup or cocoa. If we do have a lengthy outage in the winter, The chimney's clean, I have a couple of ricks of wood already cut, and an axe if I need more, and we'll probably not just manage for ourselves, but put up the little old lady across the street on our couch, take some hot soup to another neighbor or two, and so on. Plus the radios mean I'll know what sort of problem it is early, and can plan. I'll know if the problem is expected to last long enough that I'd better conserve the chainsaw for real emergencies, etc.
I'm not even sure but what that IS a potential huge net ecological savings. People who cope on their own if the big, gridded systems go down aren't as likely to be a drain on emergency services. What's the carbon footprint of a helicopter rescue operation?
I'm starting to think scaling arguments are mostly rubbish anyway. Whenever we start addressing scaling, we're talking about getting up to sizes where someone can centralize the production, and rent services to the common people. A stable, long term sustainable, ecologically sound system shouldn't assume centralized control is desirable, in fact, all other things being equal, it's a bad thing.
Who is John Cabal?
This is only a prototype, but obvious improvements would be to put magnets and coils on both ends, or along the entire length.
Picture this, you have a machine that takes two strips of heat fusible plastic and fuses them around coils of wire, so you have a roll of tape that has coils of wire embedded along its entire length.
You then have a second machine that takes a single coil of mylar and applies a thin film magnet along it's entire length. So now you have two rolls of plastic tape, one with embedded coils, the other with a thin film magnet.
Now you cut alternating strips from both spools and mount them under tension in a window frame, like horizontal louvered blinds and let the wind vibrate all of the strips. The power is being generated along the entire legnth of the strips now, and the coil wire tape and the thin film magnet tape should have different resonant frequencies so that the alternating strips will be vibrating asynchronously along their lengths. Seems like it would produce far more power this way than his original basic prototype.
I have one question. If the Japanese Ministry of Agriculture is not in charge of Gundam, then who is?
I'd like to point out that is global warming is real and we are going to do anything about it, we ALL need to learn to live with less power consumption.
Heck even if global warming is bunk, if the Chinese keep their head long rush to consume like westerners, then we are ALL going to need to do more with less.
The other question is how well will it scale?
Think Deeply.
Or take one salvaged windshield-wiper motor with a three blades. Maybe $15 for 10 watts, or $1.50 per watt. Which is cheaper and easier to install and maintain?
I dunno ... sounds like it would be blast!
The higher the technology, the sharper that two-edged sword.
Helping them through the aftermath was OK, but helping them rebuild New Orleans almost exactly the same as before? That's definitely the wrong solution. If you want to help them, help them move elsewhere. The cost to build in New Orleans should be commensurate with the risk to discourage people from building structures that cannot survive the conditions and cannot be economically insured by the parties that build or occupy them without outside subsidization.
Hiding the cost is only going to encourage more people to live more dangerously. That's not going to be so great come the next storm.
Can you be Even More Awesome?!
Yeah, it's called research and peer review.
This article is a dupe. Here's what I said about Shawn last time:
:More about Shawn at MIT by arbitraryaardvark (Score:4)
===
http://science.slashdot.org/article.pl?sid=07/10/11/212243
Low-tech Inventions That Help Change Lives
arbitraryaardvark (845916) on Thursday October 11, @07:41PM (#20947701)
(http://vark.blogspot.com/ | Last Journal: Friday October 12, @03:26AM)
http://www.wired.com/culture/lifestyle/news/2004/10/65276 [wired.com]
A MacGyver for the Third World
http://www.flickr.com/photos/aidg/612856202/in/set-72157600466239024/ [flickr.com]
flickr
http://instapundit.com/archives2/010388.php [instapundit.com]
instapundit is blogging the conference
http://www.aidg.org/component/option,com_jd-wp/Itemid,34/p,33/ [aidg.org]
some blog
Shawn Frayne is the founder of Haddock Invention LLC and its recent spin-off company, Humdinger Wind Energy, LLC. The mission of these companies is two-fold. First, to create technologies that can address long-standing problems in developing countries; and second, to leverage the novel aspects of those inventions through licensing deals in capital-rich nations such as the U.S., thereby generating a self-supporting revenue stream for the projects.
His work has so far focused in the fields of solar water disinfection, inflatable packaging, food preservation, charcoal-production, and wind power generation, with several products successfully licensed or sold. It was during his time as a student in MIT's D-Lab that Shawn first became convinced that the key inventions of the next century won't necessarily be born in wealthy countries. Rather, the new industries of the coming years will be founded on breakthrough technologies invented in Haiti or Zambia or Guatemala, where the hardest problems in the world will yield the greatest inventions.
[ Reply to This | Parent ]
even more
Starting Score: 1 point
Moderation +2
100% Interesting
Extra 'Interesting' Modifier 0 (Edit)
Karma-Bonus Modifier +1 (Edit)
Total Score: 4
nice idea, but I could imagine the noise problem as a major obstacle.
Popular Mechanics is just a front for Press Releases most of the time and probably lost most their educated staff many years ago back when I stopped reading the trash it became (not that it was ever a quality source for science news.)
Look at savonius for cheap power.
Off the top of my head:
Take the design from those shake flashlights (aka "jerk off" lights) and balance the thing so it can totter up and down enough for the magnet to slide past the coil. Then hook up just about anything that will flap in the wind to the other side...
One could also use a simple air foil which mechanically alters its own pitch (to create a wave motion) and have it pump the shake light magnet up and down... Or the magnet could be lifted up and down thru wave motion and no wind is required at all. 2 different methods of power!
Popular Mechanics can send my award money to slashdot.
Democracy Now! - uncensored, anti-establishment news
Wind power is very well understood. The power in the wind is (1/2)*p*A*v^3. Where p is air density in units (kg/m^3), A is the swept area in units (m^2) and v is the velocity of the wind in units (m/s). This is intuitive from a physics perspective if the energy of a moving object is (1/2)*m*v^2 then p*A*v is mass. Albert Betz proved that the maximum efficiency of a wind generating device is 59%. Many small wind turbines can achieve an efficiency of over 30%. From the article it says "his device [is] 10 to 30 times as efficient as the best microturbines" That would put the efficiency of the device at at least 300%. Not only is that higher than the betz limit it is higher than the energy available. A quick example. Lets use an air density of 1 and a swept area of 1 (for a rotary turbine this would be a blade radius of .56m), a wind velocity of 10mph (4.47 m/s) and an efficiency of 30%. This will make 13.4 watts of power. That would be enough to power several small led light.
Probably, but the mass and viscosity of the water would dampen out the vibrations, making it not very efficient (very low frequency).
uses unconventional wind generators too.
Democracy Now! - uncensored, anti-establishment news
uses unconventional wind generators too.
Theo Jansen
Democracy Now! - uncensored, anti-establishment news
awesome! this is a dramatic improvement of my idea to line the nation's highways with millions of cheap and disposable/easily-repairable wind-to-energy devices to recapture all that lost power!
My assessment:
pluss:
-Will not kill birds
minus:
-expensive,
-noisy, and
-inefficient
A propeller and a generator is currently mass produced, cheap and efficient. In the setup the fan probably draws 300W, and the belt generates 1W, or 0.3% efficiency. What a joke.
don't cut it off www.mgmbill.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.
Build it vertically, put the generator at the top, hang a weight on the bottom, trim it to the desired wind speed by adjusting the weight.
It might even be possible to come up with a mechanism to adjust the tension to the wind speed using a couple of levers and a vane attached to the counterweight and the frame.
I saw the tag tacomanarrows and was thinking "WTF are Man Arrows!?" for a while before I realised what the tag meant.
Me lost me cookie at the disco.
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!
I too wind interested to build one. Given the low power output, I think that stacking a few together would help increase the resultant power output. As for pointing in th right direction, a wind vane would do the job. As for having the right tension for the wind speed, I wonder whether attaching a wind speed meter would do the job, or more mechanical approach. The mechanical approach I am thinking of would be to have the 'string' weighted and then tension adjusted according to a propellor lifting the weight - its a bit sketchy at the momemnt, so I haven't decided the exact setup.
Jumpstart the tartan drive.
The Space Elevator projects face a problem of aiming their beam at a climber on a vibrating tether under tension.
Just thought I'd point this out to everyone here.
Actually, if he did patent it, then he's going to limit it's application in his intended markets (3rd world). However, even if he did, I can help him subsidize this. I know of an application in remote sensing that this would probably power; and we sell a LOT of these remote sensors...
This is more like a ribbon microphone than anything. Ways to change the output and efficiency:
1) Using super-efficient magnets and coil windings
2) Studies into super light weight and flexible materials ( preferably made out of cheap materials or waste). They would also have to be cleaned easily or not accumulate any residue from climate, or bird crap.
3) Create an auto-tensioner for the membrane that is adjusted by a sensor that detects wind speed. Could be run off a computer that has aggregate wind model data for a region synced to 24 hr. wind speeds.
4) Possible suspending of the magnet in a ferofluid that overcomes the effects of gravity and makes it that much easier for it to travel off miniscule amounts of wind.
5) Possibly using multiple nano-sized motors in an all-in-one module attached to the membrane. Maybe enclosed in a vacuum.
-The best possible thing would for every manufacturer to start making DC power supplies for their products instead of AC. If everyone was using DC instead of AC with the supply coming from their own property, you would not have to worry about transmission losses and distribution. DC would be more efficient. This was the whole debate when AC and DC power were first developed and trying to get public support. The power equivalent of BETA vs. VHS.
Why don't we choose the best energy system we have today. Simply modelled, it is a superconductor ring with an EM wave travelling around it. When the wave travels through an inductor connected to a secondary circuit it produces a current in that secondary circuit. I know about its existence as I was stabbed by an arseXXXX when I started talking to people about it (approx 1-2 years ago). It is free energy. It is non-polluting, probably uses very low pressure nitrogen as a refrigerant, does not explode when cracked, provides unlimited energy (you don't turn it off) etc. My blog is at http://overunityenergy.blogspot.com/ and provides other evidence of its existence.
One of the neater aspects about this project is that you can build it out of trash you have laying around. Salvage magnets from headphones or speakers, salvage magnet wire from a motor, build the frame out of whateverthehell you have laying around, and use a strip of waxed silk or something for the ribbon. You need a little bit more know-how to turn that into DC, but that's also very basic, and the components could also be salvaged from just about anything. Hell, same thing with LEDs. Let's face it, people in the third world are superb scavengers -- look at the sudden proliferation of satellite dishes made from hammered-out cans that popped up in Afghanistan after we toppled their regime.
I think the magnet placement is a concession to engineering; if it oscillates too much it may not enter the magnet cavity property.
Piezoelectric transducers defeat the beauty of this project, which is that pretty much any component can be replaced by a trip to a trash heap.
Most modern wind turbines don't have a gearbox. That's one of the reasons a 1G windpark is more quiet nowadays than an 1G coal or nuclear power station.
Trust me, I work for the government.
...the first thing that came to mind when I S(kimmed)TFA was those little flashlights that you shake up to charge. Could this tower design be expanded by, say, multiple magnets/coils along the length of the belt? I'm not talking about a large number of magnets, or anything particularly heavy of course, just something that will add a little extra kick to the single-magnet design shown in the article, without adding to the device's physical footprint.
Wouldn't you want more tension for higher wind speeds? It seems that what you are suggesting would work the other way around.
I think the best way would be to have a paddle that faces into the wind and is attached to the tensioning of the belt (possibly some gearing needed here to get the appropriate level of tightening) - when the wind blows the paddle move back and pulls the belt righter!
Don't believe the nonsense, unless you hear it from me directly.
In contrast, this new vertical idea is tuned for low wind conditions, low power gen, and for all practical intents and purposes has one moving part. Pure genius in terms of non-grid electrical usage. A right sized windvane plus a much more moderate PV panel and charging system would be enough for a rural-minimal power setup, or maybe to be the seed power for another form of energy generation: a methane digester which basically can take any form of tiny chopped up bio-waste or *ahem* post-digested organic materials... and when blended with water and allowed to stew properly at the right temps will produce moderate amounts of methane that can be used for heating, cooling, and power apps...
Let's see where this pans out....
...Open Source isn't the only answer -- but it's almost always a better value than the alternatives...
"Haven't you ever made a blade of grass whistle between your thumbs?"
I'm whistling impaired, you insensitive clod!
"As God is my witness, I thought turkeys could fly." A. Carlson
Glad to see I'm not the only one who thought of dynamic tension on the ribbon.
Personally I had envisioned a wind-speed prop (doesn't have to be big) that drives a governor, that is in turn attached to a spring-loaded tensioner. A kite, or similar mechanical analog like your string, attached to a tensioner might work too.
Ultimately, I think it comes down to generating enough torque to adjust tension in a way that isn't completely overcome by the torque generated by the resonance of the ribbon. Perhaps something electro-mechanical that can *lock* into place on specific tension settings (like shifting gears in a car - do turbines even do that?) is the way to go.
Produce the coil, magnet and rectifier as a module. Ship it to third world countries either with the airfoil, possibly in kit form so that they might be able to assemble it locally. In addition, make the generator module available separately. Some innovative locals might be able to find some other sources of reciprocating motion that they can harness for a small amount of power.
Have gnu, will travel.
Hi,
Thanks for your comments: I've posted this response on another thread, but I'm trying to nip this in the bud, so here it is again. The Windbelt generator as it's currently sized is 10X more efficient than the current state of the art in microturbines on the same size scales. Importantly, this claim is with reference to 'micro'turbines. Definitely not 10X more efficient than turbines on the large scale. Here are some references from a recent article that you can use to do your own due diligence:
http://www.humdingerwind.com/docs/Handheld%20windmills%20serve%20as%20electric%20generators.pdf
http://www.humdingerwind.com/docs/ApplPhysLett_priya.pdf
The device noted in these articles (with which I am not affiliated) is the micro-turbine that got a lot of press a few years ago after Nature published a small article about Wind-powered Wi-Fi. I thought this was a good benchmark for comparison purposes.
I do appreciate the hesitation that folks have at first reading the claims. I am absolutely not claiming to have made a "Betz buster". We've used a particular point of reference based on an article in Nature as the "state-of-the-art" in microturbines, and then compared the Windbelt to that reference. Turbines on the large scale have efficiencies slightly higher than the current Windbelt variations we've experimented with in the past. That said, we are presently experimenting with larger scales (1-20W range, 2-3 meter tall belts) which may show different characteristics. Maybe.
Perhaps needless to say, in a rural lighting application, the cost/watt and the entry level price to light something up are the two aspects that matter most, and not the energy efficiency. They are related, definitely, but cost is the name of the game when dealing with these sorts of applications.
I hope this clears things up a bit -- thanks for all your interest, and keep an eye on humdingerwind.com in mid-January 2008, when we plan to post a tech brief of how to make your own Windbelt from scratch. This hopefully will let people do some peer-review on this new technology.
-Shawn Frayne
humdingerwind.com
Hi,
Thanks for your comments: I've posted this response on another thread, but I'm trying to nip this in the bud, so here it is again. The Windbelt generator as it's currently sized is 10X more efficient than the current state of the art in microturbines on the same size scales. Importantly, this claim is with reference to 'micro'turbines. Definitely not 10X more efficient than turbines on the large scale. Here are some references from a recent article that you can use to do your own due diligence:
http://www.humdingerwind.com/docs/Handheld%20windmills%20serve%20as%20electric%20generators.pdf [humdingerwind.com]
http://www.humdingerwind.com/docs/ApplPhysLett_priya.pdf [humdingerwind.com]
The device noted in these articles (with which I am not affiliated) is the micro-turbine that got a lot of press a few years ago after Nature published a small article about Wind-powered Wi-Fi. I thought this was a good benchmark for comparison purposes.
I do appreciate the hesitation that folks have at first reading the claims. I am absolutely not claiming to have made a "Betz buster". We've used a particular point of reference based on an article in Nature as the "state-of-the-art" in microturbines, and then compared the Windbelt to that reference. Turbines on the large scale have efficiencies slightly higher than the current Windbelt variations we've experimented with in the past. That said, we are presently experimenting with larger scales (1-20W range, 2-3 meter tall belts) which may show different characteristics. Maybe. This is new stuff, and hopefully a lot of folks get their hands into it.
Regardless, as you note, in a rural lighting application, the cost/watt and the entry level price to light something up are the two aspects that matter most, and not the energy efficiency. They are related, definitely, but cost is the name of the game when dealing with these sorts of applications.
I hope this clears things up a bit -- thanks for all your interest, and keep an eye on humdingerwind.com in mid-January 2008, when we plan to post a tech brief of how to make your own Windbelt from scratch. This hopefully will let people do some peer-review on this new technology.
-Shawn Frayne
humdingerwind.com
How is this only +2 6 days out? ... no mod points for me to use :-(