9 ms·
Sheerwind
- arianvanp 13y agoThe way it looks really gives you the feeling like this d'ni engineering. Except this is real! Ok, back to playing Myst
- x0054 13y agoThis looks like an amazing idea. How can I invest in this?
- icebraining 13y agoClick on "Investors"?
- rpedela 13y ago600% sounds impressive, but what is the typical output of wind turbines in absolute terms?
- kubiiii 13y agoIf the windspeed is lower than required for the wind turbine to operate, you can get + infinite % more kwh with this technology.
- rpedela 13y agoFind that hard to believe, and that doesn't answer my question.
- jeena 13y agoYes it does, if the wind is too slow for a normal turbine the normal one outputs 0 kw/h and this one more then 0 and therfore if you let it do its job it will naturally produce much more power then the one which doesn't produce anything.
- brazzy 13y agoIf I look at http://sheerwind.com/technology/field-data http://sheerwind.com/technology/field-data it seems to me the 600% improvement is highly deceptive: that huge funnel tower gives up to 600% (average 300%) more output than the same tiny turbine inside it when it's just placed on top of a pole. If you want to use this technology to boost the output of a modern 100m diameter turbine by 300%, you'd need to build a funnel tower that's over 1km high. I kinda doubt that's cheapter than building three of those turbines.
- Alex_MJ 13y agoAlso, the longer tube you build the less effective the system becomes because the pressure at the top has to move the entire column of [viscous, turbulent] air down the pipe. I haven't done any math on this but I'd imagine it would not take that much height to hit a point at which point piping losses become overwhelmingly large in proportion to the energy you're producing. The turbine and the inlet need to be close together.
- Gurkenglas 13y agoMaybe by "the same turbine" they mean the generator at the center, having swapped out the short blades shown on their site for a traditional set.
- brazzy 13y agoDoesn't look like it, neither in the photo nor the comparison table. Besides, I doubt that it's even built to allow that.
- mschaecher 13y agoI had to dig into that one too. I lost where I found it, but it's actually "up to 600%." Range is 85%-600% with average of like 315% or something.
- gscott 13y agoI applied to ycombinator with this idea two years ago, I read an article about how the wind turbines were driving people who live near them crazy with the noise they create. Having a funnel that would capture the wind, then put it through a turbine, plus the ability to channel the wind, seemed like a good idea. However I am not an engineer, never finished college, and am over 35 which may have hurt my application :)
- tinco 13y agoHi, please don't be fatalist over those things, that's just being unconstructive. You were probably rejected because you had no engineer to validate your idea.
- CmonDev 13y agoDid you present a plan of how to inflate the price of the start-up rapidly for a quick sell-off?
- gscott 13y agoThat was the challenge, I couldn't think of a way to make everyone in the whole world want the product but it seemed like an interesting problem because giant blades spinning just can't be the future of wind energy. The blades take out too many birds and make too much noise. There is a wind energy project maybe 40 miles from me, the installation of the towers and movement of the dirt has caused dust storms for the local residents. A funnel system could be longer and have more support of a wider area, requiring less digging. Big corporations would only switch if they can build it for less and make more money through additional production from each unit so it is unlikely there is big money in developing it, it would have to be a Bill Gates type save the world project and give the designs away for free.
- scythe 13y agoUnfortunately, I think part of the reason your idea was rejected was that it's just a bad idea. The thing is, you -- non-collegiate, over 35 -- are nonetheless capable of doing enough research yourself to determine if an idea is very good. One thing to consider is the cross-sectional area of the funnel -- the size of the mouth. Another is a relation mentioned here: the power available (dF/dT) in wind is proportional to v^3. You can look up "power available in wind" here: http://en.wikipedia.org/wiki/Wind_power http://en.wikipedia.org/wiki/Wind_power You'll be able to test your idea by considering a few scenarios, like "how does the force on the funnel (~area v^2) relate to the power generated (~area v^3) and is this practical?" and "Where would wind farms most likely be located, based on power availability (remote high-wind areas)?". I say this not [primarily] as a criticism, but to hopefully recommend to people that they can use simple math to test their ideas using pubically available information. It helps you form ideas with a closer relationship to reality. Doing research can be good for you, and elementary physics shouldn't be daunting, especially if you're taking things as far as applying for angel funding. Having a broader knowledge base doesn't hurt for coming up with ideas, either.
- deleted 13y ago[deleted]
- Gurkenglas 13y agoIf the wind gets slowed by turning the turbine, shouldn't the output side funnel of the turbine be larger than the input side funnel to be able to hold more air? (So the additional wind coming in from behind doesn't have to waste its own kinetic energy pushing the front air out of the system)
- mgraczyk 13y agoI believe the output side should as wide as possible while still preventing turbulent flow, as would exist if there were no output tube.
- Gurkenglas 13y agoWould turbulences be prevented if 3 radial blades (3 so the 45:15=3fold amount of air can pass without problem) divided the wind from the turbine into 3 funnels as large as the input funnel?
- monsterix 13y agoOkay so it starts with normal wind at as little as 2mph (influx) and then with series of venturi tubes and processes the wind is sped up to 45 miles per hour. Then the blast is shoved through a turbine generating electricity and an exit wind at 15 miles per hour (efflux). All right. So why not take this efflux wind at 15mph back to the top again, or even half way with some loss of course, and achieve a perpetual motion machine [1]? Is something missing in the introduction video about this concept? [1] http://en.wikipedia.org/wiki/Perpetual_motion http://en.wikipedia.org/wiki/Perpetual_motion [Okay got it: The blade area/size of a fan to turn at winds as low as 2mph is quite high (and expensive) as compared to rotor blade size that would work with winds at speed 45 miles per hour. This one looks like a play on lever action of wind on fan blade area/angle w.r.t achievable influx velocity. Not too bad it's a kind of optimization, but for the introduction video that wasn't clear enough.]
- rytis 13y agotake this efflux wind at 15mph back to the top again you need energy to do that, so perhaps by the time 15mph wind gets all the way up to the tower influx, it's less than 2mph
- praptak 13y agoThis is not the reason why it won't work. The 15mph flow will be much thinner than the original input flow, so feeding it back into the top will not have the same effect.
- mgraczyk 13y agoFluids move faster in a smaller tube. http://en.wikipedia.org/wiki/Bernoulli's_principle http://en.wikipedia.org/wiki/Bernoulli's_principle (Search for [18] in the Wikipedia article. Note that if z and p decrease from the air being lower and in a smaller pipe, then v increases.) The reason to make it go faster is that you can't spin a turbine to generate electricity if the wind is 2mph, unless the turbine is really, really big.
- monsterix 13y ago
- forktheif 13y agoInteresting, but I'd like to hear from someone other than the company that's making them. I'm kinda suspicious when I only hear the upsides to something like this.
- aquadrop 13y agoIf it really works it's amazing. But I won't believe it until more information is disclosed and some independent experimental data provided.
- knowitall 13y agoIt seems to lack any kind of physical explanation of why it should be more efficient than traditional turbines? All it says is that it uses a smaller turbine - are those more efficient? I would have expected larger turbines to be more efficient (just on the grounds of larger fans in PCs making less noise...)? It seems irrelevant if the turbine is sitting on the ground or not. "Accelerating" the wind also seems kind of irrelevant - they can't create energy that way. However, if they manage to drive a turbine with little wind that way that would otherwise not have worked, perhaps it is a win. Maybe it is a good technology, just saying that I don't see any reason in the text of why it should be. At least they could have written "small turbines are x% more efficient than large turbines" or sth like that.
- jeena 13y agoThey say they can generate electricity at much lower wind velocities already, long before a normal big blade could.
- adamnemecek 13y agoHate to be that guy but sounds a little too good to be true.
- yardie 13y agoAccording to my old aeronautics professor, 2-blade turbines are the most efficient when pointed directly into the wind. They've tested 3-blade, 5-blade, and vertical turbines and couldn't get the same amount of output. These experimental turbines look great on paper but rarely scale up. The reason why 3-blade is the most common design is 2-blade turbines induce a lot of harmonics at high speed. 3-blade cancels it out but are slightly noisier from the blades slicing through the spoiled air.
- mschaecher 13y agoIf I read various parts of their website correctly it sounds like they aren't in the turbine business(yet), but building this funnel thing around many existing turbines.
- neumann 13y agoActually it is the opposite [1]. Efficiency is theoretically increased with more blades. The three-bladed turbine is the most popular because of the cost benefit of building blades vs efficiency gain of extra blades - although the case of harmonics for even number of blades does hold true. [1] http://onlinelibrary.wiley.com/doi/10.1002/we.274/abstract http://onlinelibrary.wiley.com/doi/10.1002/we.274/abstract
- weland 13y agoI am not an expert in wind turbines, but I am technically an EE, so I have seen a thing or two. I have mixed feelings about this. On one hand, the principle of operation superficially looks OK. The weird shape probably gives more flexibility in the design (I say probably because I honestly don't know anything serious about fluid mechanics). The data they provide seems usable. That being said, the website is fairly scarce in terms of actual details (e.g. the "collected wind is channeled to pick up speed" doesn't seem to be explained anywhere -- how exactly is that done, and how much speed would the wind gain?), and the only paper they published looks rather meagre -- from the works they cite to the dubious editing of the paper (e.g. last sentence before "Conclusions": "The total energy production of INVELOX over 8 days is about 314%" would not have made it past decent peer reviewing). I don't know enough about mechanics to make a proper assessment of this, but my bullshit detector is bleeping, though shyly. Edit: BTW, the website also seems to casually glance over what the (up to) 600% improvement improves upon. If I read their article correctly, it's an improvement over using the same turbine, but without the funky tunnel. In that case, I kindda doubt the economical feasibility of this design.
- pingswept 13y agoYour BS detector should be bleeping at full force. There is a long, long history of failed attempts to build ducted wind turbines. The fundamental question is whether, for the revenue you'll gain from the energy gains, it's more efficient to put the money into building a duct or extending your turbine blades a bit more. Unfortunately, building all the extra structure to support the duct is expensive. The history is long and discouraging. Paul Gipe has some good photos of recent attempts: http://www.wind-works.org/cms/index.php?id=541 http://www.wind-works.org/cms/index.php?id=541
- kubiiii 13y agoYes, at first I thought that the x6 improvement was over real scale turbine or at least a turbine of comparable bulkiness. In France more and more people put wind turbines on their roofs, even if the kwh production is far less than promised by manufacturers (gaps between forecast production and real production of +6000 %, yes that's 60 x are common). The authorities are even giving subsidies for the installation of those inefficient turbines. This might prove better for small scale installations.
- malandrew 13y agoI'm not specialist in fluid dynamics or wind, but isn't some energy going to be robbed by the intakes on the sides not receiving the brunt of the wind? I would imagine that the passive sides would rob the tunnel of pressure. However, if this problem exists and does reduce efficiency, I reckon it's an easy fix that just requires adding dampers for each of the channels and opening them for the ones receiving wind and closing them when not receiving wind. Out of curiosity, what's the fluid dynamics equivalent of a parabola for energy rays? i.e what shapes are known to concentrate and accelerate fluids best? I know a venturi nozzle is one such shape for acceleration of already collected fluids. What's the best collector shape?
- ars 13y agoThey would have to use dampers. Otherwise the wind will enter one side, flow down the tube, then right back up the other side since there is less resistance that way compared to pushing a turbine. You could use passive dampers - just a flap basically.
- varjag 13y agoThe mechanical power carried by wind is normally a cube function of its speed, which suggests that the surface area to generate substantial output from slow winds have to be enormous. This doesn't seem to be the case here. Until there's an independent confirmation (and there seems to be none so far), I'd file it next to cold fusion folder.
- JackWebbHeller 13y agoWhy is the funnel intake octagonal? Making it circular would be more aesthetically pleasing, or is there a technical reason why having 8 'separate' entrances is required? Secondly, paint the funnel intake and top section green, and the 'trunk' brown, stick these on top of a hill, and from a distance it could pass for a tree. Much more visually pleasing than a traditional wind turbine.
- computer 13y agoI suspect the walls in between the "separate entrances" force the wind moving semi-perpendicular to those walls into the entrance as well. Removing them would lose wind.
- dustyleary 13y agoWithout the compartments/channels/separate entrances, wind blowing in from one direction would mostly just go around the central pillar, rather than down into the funnel.
- ars 13y ago> Much more visually pleasing than a traditional wind turbine. But also much larger. It's an inescapable fact that wind energy is proportional to the area captured. So these would have to be as tall and wide as turbine blades. Except it would be a massive structure, not just a small thin blade on a pole. And don't think they could get away with flimsy walls either - the pressure of the wind on this thing is the same as the pressure on a regular turbine. I suspect this last point will sink this project except perhaps in zones with very light wind that can benefit from it's ability to generate with low wind speed (and low pressure, so a weaker structure).
- moocowduckquack 13y agoI doubt that the aesthetics are the prime design consideration. This is to generate electricity, not to stick in a gallery. Power generation isn't generally pretty, but it keeps people alive in the winter.
- elithrar 13y ago
- kermorvan 13y agoThis looks much more difficult to clean, think of all the bugs, birds and sediment that will stick to the INSIDE of that funnel structure. Cleaning the blades of an ordinary wind generator seems much simpler. On the other hand, if this is as tall as they will get, it seems a lot safer to work on than the current behemoths.
- VLM 13y agoIn northern areas I think freezing rain would be extraordinarily exciting.
- mmcclellan 13y agoIt looked good enough to Google to me. Sheerwind hoax is my 4th suggested search.
- bmatthews60 13y agoWhy is this better than just putting a big cone around a small conventional wind turbine? That would also 'concentrate' the wind.
- scblock 13y agoIt's being done, actually. Company called Ogin (was FloDesign Wind Turbine) is developing a 100 kW shrouded wind turbine that is similar to that idea. But it only works on small machines, can you imagine a 100 meter rotor with a shroud around it? http://oginenergy.com/ http://oginenergy.com/
- lafar6502 13y agoOk, the air would flow into the channel facing the wind, but wouldn't it also be sucked out by the side channels as the wind passes by? A movement of air creates a pressure drop proportional to the speed of wind so there would be a sucking force on both sides of the tower (Venturi effect) - did they address that?
- jeena 13y agoI assume you could have something which only lets air in but not out, like a https://en.wikipedia.org/wiki/Check_valve https://en.wikipedia.org/wiki/Check_valve but for wind.
- lafar6502 13y agoYes, but they aren't mentioning that, and I suppose this is quite an important ommission. And btw, valves would create additional drag and reduce efficiency of the device.
- jeena 13y agoIn their FAQ they say: - What are the details of the system inside? Sorry, we do not comment on the details of the inside of our INVELOX system because they are part of our trade secret. So it is not unreasonable to assume that they have something in there. And they could be needing the valve anyway to close the tube if the wind is too strong to protect the turbine.
- lafar6502 13y agoThere's a paper published by sheerwind, detailing the principles of operation - http://sheerwind.com/wp-content/uploads/sheerwind/2012/10/Allaei-Andreopoulos_ASME-ES-FuelCell2013-18311.pdf http://sheerwind.com/wp-content/uploads/sheerwind/2012/10/Al.... There's no mention of any valves, too. But there's a more interesting claim they make: "(...) INVELOX captures the wind kinetic energy and uses the pressure differentials to increase the kinetic energy available to a turbine". I wonder how they manage to increase the kinetic energy of air flow without any external energy source.
- astrobe_ 13y agoPlus, in deserts one can collect water at the same time.
- robewald 13y agoThis is a nice concept. In populated areas there is quite a bit of pushback from the population to install wind turbines due to the distracting movement of the blades and their shadows. This idea solves that nicely by hiding the turbine. Maybe the marked for this is densely populated Europe?
- gambiting 13y agoI feel like this is worse though, as a tower like that looks million times worse than a wind turbine. I would hate if structures like that started appearing across the landscape.
- jokoon 13y agoAt first I thought this was a joke or some april fool.
- DanBC 13y agoIs this really real, or is this something misguided like the "flowerpot candle heater"?
- rikkus 13y agoWas a bit worried until I saw 'Wind returns to environment.' Thought they were going to keep it.
- tzaman 13y agoThe first question that popped my mind is how long until the amount of produced energy exceeds the amount needed to build such a device.
- fpp 13y agoThere has been a lot of hype on low wind speed energy production for years and Sheerwind is just one of the "contestants" of challenging the laws of physics - i.e. there is only so much energy per m3 air / wind power density provided with low wind speeds and you can't harvest more than 100% - also see Betz's law. For a good overview of novelty wind energy approaches (taken with a grain of salt) - http://barnardonwind.com/2013/06/03/good-and-bad-bets-new-wind-technologies-rated/ http://barnardonwind.com/2013/06/03/good-and-bad-bets-new-wi...
- msandford 13y agoThis is an optimization, they're not trying to extract more energy than the wind contains. They're taking 500sqft of wind and channeling it down to 100sqft where their 100sqft wind turbine is. 2mph*500sqft/100sqft = 10mph ignoring all the viscous losses and backpressure, both of which there will certainly be some of. So perhaps instead of 10mph you get 8mph. What they've done is made a 100sqft wind turbine which would have a high cut-in speed effectively a 500sqft wind turbine with a lower cut-in speed. No magic, just a bit of clever engineering provided that the tower is cheaper than the 500sqft wind turbine.
- __alexs 13y agoThis design optimises for low-wind speeds by exploiting the Bernoulli Principle but the problem with doing that is that there is very little energy available in the wind at low speeds to begin with. It's more practical to aim at higher wind speed sites (e.g. off-shore, or simply by being much taller) simply because there is vastly more energy.
- chrisfarms 13y ago> The unit is about 50% shorter than traditional wind towers This is the same thing people say about VAWTs... but they don't build HAWTs really tall just for fun, the wind speed is faster and more consistent up there. So all they are really saying is "the one we built isn't very big" I think the biggest benefit to this design is that it looks like it could be dirt cheap to make and maintain since it appears to have very few moving parts exposed to the elements.
- lotsofcows 13y ago"Wind returns to the environment"? Ahh, running wildly as wind should. Presumably, they mean, "some wind returns to the environment"? Currently, I'm reading that as, "massively inefficient". And it doesn't really "return to the environment" anyway, does it? It's channelled, focused and ?most? of the power is removed.
- keeran 13y agoIs this the same technique employed by the Windcatcher [1] (rapid inflation) [1] http://www.kickstarter.com/projects/1484284472/windcatcher-inflates-in-seconds-with-no-power-or-p http://www.kickstarter.com/projects/1484284472/windcatcher-i...
- deleted 13y ago[deleted]
- stefantalpalaru 13y agoWhat if the wind blows towards the bottom opening of the funnel?
- stormcrowsx 13y agoThe wind moving out of the opening is moving at 15 mph and the wind moving toward the opening would be at 2 mph. The 15 mph wind will win.
- whage 13y agoThe swept area of regular wind turbines seems enormous compared to sheerwind's turbine's. Even the combined area of those 8 entrances look much much smaller. How in the world is this going to compete with those giants? What am I missing?
- venomsnake 13y agoThat you could deploy them anywhere probably - if you put enough on rooftops you could squeeze enough juice for home operation and a change. I can see something like that as a complementary power generator - it is very cheap if produced correctly.
- danmaz74 13y agoWhy would the "swept area" be meaningful? It's the blades that get the kinetic energy from the wind, not the space between the blades.
- whage 13y agodon't be silly, you just claimed that it doesn't matter whether you have 3 meter blades or 30 meter ones. Of course the swept area matters. P = 1/2 x ρ x A x v3 where ρ = air density, A = swept area and v = velocity of the wind
- danmaz74 13y agoDon't be silly yourself. What happens if you add or remove a blade, or change their shape or pitch? The swept area stays the same, but the energy captured changes. The "swept area" is a useful abstraction that gives us the total energy that you can extract from - with your formula - but it's the blades being there with their length that extract that energy. These wind towers on the other hand capture and manipulate the whole air flow from the area of their intake, not just the part directly interacting with the blades of a traditional turbine. That's why it is physically possible to extract much more power than with a traditional turbine with an equivalent "swept area".
- alfor 13y agoNo, it doesn't work. The same principle have been posted many times. The only important thing, is the surface area of the collector, that where the energy comme from. In this case, think about the cost of all this structure vs the same area swept by a blade. The cost of the simple blade is always lower than the same area of 'concentrating funnel'. Right now they are building turbine with blade of 90m of diameter, imagine building a concentrating structure of the same size.
- jpadkins 13y agoRight, but is the mfging and installation costs of the 90m blade vs. the structure of the same size? I see this as a cost optimization, not a way to get more energy from the same source.
- chrisbennet 13y ago"A single experiment is worth a thousand expert opinions."
- ISL 13y agoA single correct experiment, perhaps.
- Houshalter 13y agoOpinions are cheap, experiments are expensive.
- doubt_me 13y agoI just saw one being put up in Rosemont, Illinois last week That thing was huge.
- eliteraspberrie 13y agoAs others have mentioned, the air increases in speed because of the Bernoulli principle: the decreased cross-section increases the dynamic pressure. However, most of the power will be lost in friction, during the "channeling" part -- and the increase in speed will not make up for that loss. The friction is relatively high because the flow is turbulent, not laminar. The friction factor can be calculated with the Colebrook equation, implicitly; if they did the calculation they would realize that the distance between the intake and the turbine is a mistake (especially the height difference, which doesn't make sense for atmospheric flow). It would be better to use natural land features that create the kind of flow you need, such as mountains. Look at the figures here for inspiration: http://journals.ametsoc.org/doi/pdf/10.1175/1520-0469%281973%29030%3C0801%3AATSOTF%3E2.0.CO%3B2 http://journals.ametsoc.org/doi/pdf/10.1175/1520-0469%281973...
- ancientrepeat 13y agoThe physical rationale is fundamentally flawed. It assumes that all wind that is "caught" will enter on the big opening and all of it will leave on the small opening. But that is wrong, the smaller of the narrow region the less wind enters the entire construction. The fundamental flaw of the rationale is that it confounds the concept of an engine to that of wind entering the tube. If you suck cold air into a compartment via a valve and provide heat inside it the air expands rapidly and must leave because it does not fit inside anymore. But note how we spend a lot of energy to expand the air and turn that internal energy into mechanical energy. There is absolutely no way that you could get air freely inside of a tube and have it "speed" up without actually pushing back on the air that is coming in. Imagine that you close the narrow part completely. What happens? Will the construction blow up, of course not? Will the the pressure inside rise to a high value? Of course not. It will simply fill up with air and will experience as much pressure as the wall of the building is subjected to. Can you make the closure experience more pressure than any other part of the building? No that is not how pressure works, it is uniform inside the building. Now imagine that you make a teeny tiny hole in the closed area. Will that lead to air leaking at insane speeds? No it will be barely noticeable, almost no air would be coming out. There is no reason whatsoever that the air would voluntarily go into a building than on it is own choose to leave on the tiny hole instead of leaving the same way where it got in (basically it is not getting in at all because the pressure inside is the same as outside) Does it work, of course to some extent, take the area of the building that catches wind, multiply it with the speed of the wind and density of the air and you get the the mass and volume of air that is moving. Air is actually pretty light, you would be surprised how big the area needs to be.
- tomrod 13y agoAmazing technology! Again I protest the design decision of light gray text on a gray/white background. Higher contrast! :) (sorry to be a broken record).
- dojomouse 13y agoThis is an absolutely awful idea, as it was every other time someone's had it. Consider the following: a) The maximum amount of energy you can get from some wind is a function of the velocity and density of the air and the projected area of your generator. You can't go above 59.3% of the original kinetic energy content. Conventional three axis turbines get pretty damn close to this limit (80% or so). b) That being the case, getting cheaper or better power is a matter of getting a large projected area for a low cost while still keeping pretty good efficiency. c) If you cover a large projected area with a small amount of material, and can point your projection to face the wind... you will do quite well. This is what conventional turbines do. d) If you cover a large projected area with an even smaller amount of material you may do VERY well. This is what Makani power acheived before they were absorbed into GoogleX. e) If you cover a small projected area using an astronomical amount of material, which doesn't turn but is rather built for every direction, you can expect to do really really badly... no matter how many bullshit mystery air acceleration tubes you include. It's bullshit. *edit: I know nothing about the people who are proposing it. They may be doing so in good faith and not realize it's a terrible idea. But it's still a terrible idea.
- shenoybr 13y agoThis reminds me of 'windcatchers' that humans have been using for centuries. https://en.wikipedia.org/wiki/Windcatcher https://en.wikipedia.org/wiki/Windcatcher