Tom Scott - This tiny hovercraft went viral.
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thank you!
will be a good read with a cuppa!
well sign posted!
Could hanging wind turbines make any sense?
Dear all, an idea is haunting me since a couple of months which may be a bit off-topic, but related to AWE, so I would like to tap your combined expertise to find out whether (and why) this is completely crazy and doomed, or already old and described somewhere else (where?), or if it is indeed an idea that may have potential. Also please let me know if this is not the right place to discuss the idea and tell me where it should be moved if there is a better place.
I am aware of the well-know arguments in favor of AWE (better winds, potentially less material & lower cost, less interference with nature and people living nearby), but I also observe that AWE is incredibly hard to implement in real life. My explanation is simple: Tapping wind in high altitude has huge potential, but building scalable and robust devices that fly under often adverse conditions is also extremely hard, which makes it immensely challenging to compete against the tremendous successes of main stream wind energy which has undergone decades of optimization and scaling.
My proposal: a compromise and maybe an intermediate step toward AWE could be to try and reach high altitudes without actually flying.
The next best thing I can think of is to hang a WT from a support that is already in high altitudes, such as a steel cable spanned between mountain tops (like in aerial lifts) or between poles/masts/towers, held by guy-wires if needed.
The idea would be that on one such cable we could have several or even many, perhaps smaller wind turbines that hang down, but may move sideways in the wind. The cable could also support electrical wires that bring the harvested energy down to earth. I think the idea is compatible with quite a number of shapes the turbines may have, including VAWTs, laddermills, some variant of Doug Selsamās superturbines or anything else one could dream of. In all cases, I see it as an advantage that there is no need to work against gravity, but gravity can be our friend, and even if there is no wind, the devices, however they may look like, do not need to be landed but can just hang around waiting for the next opportunity to generate electricity. In my view that might take out just enough complexity to make the whole thing feasible in a not-so-distant future (given my age and the urgency of the matter I want to focus on things I may still see working in the coming two decades). A hanging WT with the possibility to move/bend sideways could also help to address one of the drawbacks of VAWT, namely the inability to be turned out of the wind if it is too strong.
Has anything like this ever been described or worked out? Are there even patents or practical explorations? Or is this idea completely dead in the water for obvious reasons I just do not manage to see? Could someone please help me out?
Thanks a lot for your opinions on this!
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Probably dead in the water. But this is too abstract perhaps to make definitive statements about.
The most obvious use would be undersea, but that has obvious probably insurmountable difficulties. See a recent discussion:
What does wind look like in the mountains? Where are some steep windy mountains? Can you make or grow a cheaper tower?
I know Selsam had some concepts like that, with a wire over a valleyā¦
I also think itās an idea worth exploring more.
There was a proposal - think it was called a wind dam.
I drew a few ideas waaay back. And flew a valley suspended daisy kite turbine.
The advantage of mountain gaps as pre raised rigid structure seems obviously worth investigating.
I worked on an algorithm to take a set of anchor points and then fill the bounded volume with tensile rope lattice (like kids 3d climbing frames)
Using structures like that for infilling gaps with fixed āflyingā utility and generation elements could also be really handy.
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An alternative method to suspending an AWE device between mountains is to have a method of rapid retraction of the kite if wind conditions are unstable too strong, or the wind dies completely. One concept is my idea of using a [RESTRAINED LIFTER KITE] to launch and land. Launching and landing is intrinsically safer than trying to limit overspeed by furloughing or various other means. If we assume that the kite is flying at an altitude of 1000 m and we can retract the kite at a speed of 12 m/s, then the kite can be lowered in only 1.4 minutes which is a reasonable time. With the ability to launch and land we do not require strong materials for the kite and turbine system and so the system can be constructed of lighter materials.
Interesting this discussion about the wind gradient in the annual report. They are using a power 1/4 whereas the āstandardā value used today is more 1/7 for the wind profile power law. The power 1/4 would correspond to the stable boundary layer. I recommend this paper for this interesting by wind at sea with experimental evidences https://www.researchgate.net/publication/354631486_PRELIMINARY_RESULTS_ON_MEASUREMENTS_OF_THE_ATMOSPHERIC_BOUNDARY_LAYER_OVER_THE_ATLANTIC
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I once though about this at small scale when I was doing a hackathon in Matera for the kiderwind project Redirecting...
It didnāt go further, but I think you can test at small scale (should be difficult enough already !), but you might find some niche applications.
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if i may interject? there is a few ways. if going for suspended AWES?
1.cable across any canyon or ravine?
2. fix to pre existing structure like bridges or viaducts?
the grand canyon would make for an awesome site if you were to go the cable route?
Britain has loads of abandoned railway infrastructure? i suspect it like that in many place round the world? so would not take muck to retrofit? many are in deep valleys anyway?
with this option you do have the potential for using less primary materials? and its one way to make the railways a we bit greener? absolutely thousands of bridges and viaducts to choose from? there might even be opportunities to restore damaged infrastructure?
though it donāt have to be conventional three bladed turbine. to work? just depend on what you hope to rig up?
donāt quote me here? but there may have been a few proposals to stretch solar across a ravine using cables? i wish i had more info than that? quick picture i saw a few years pack i wish i had remembered exactly who posted it and where? if true that would mean it can be on multiple levels?
as for my machinations on this? which i have had several Iāve been meaning to write down? one involve a multi purpose bridge across the biggest gap you can find? my dreaming were more local to me. like old harry to the needles. a city inside a bridge? even a use bridge for cargo transfer? even water treatment and other services like road and rail, coms, electrical? was even thing of building and airport on the bridge? im sure the MOD would like a super secret base? HMS bridge? because most modern bridges use down force. like the seven bridge does? most are hollow?
there is potential for awes application. because of my special interests in engineering structures thereās a mind to various techniques used historically? like box girder bridges? and old architectural features like segmented arches? that are completely self supporting?
in essence segmented box girder bridge? im lucky that few people have done the geological work in my area? so ive a rough idea where fault zones are? and roughly what dynamics are in play? university of Southampton has some information on the rock in my region
Geology of the Wessex Coast, Southern England by Ian West - Index and Home Page (soton.ac.uk) and
there is a lot more read on the university of Southampton website link.
this would come in a category of mega awes? geo engineering? in my mind its possible? it a question to how practical it would be? as you need the geological surveys? just to asses thrust pressure on the geology? so you need to know exactly where the faults are? one man made earthquake? bye bye bridge? obviously this would need to be dialled in for any region? especial because of the compression force being so high? that it would act like a hydraulic press? on the rock? which would shatter and pulverise the rock? a careful design would have to be chosen?
the bridge option possibly the quickest solution? because of the massive swept area? this would also could be an aeromine variant with jet turbine built into the super structure? there was talk of bridging the baring strait for the trans global network? it was figuring out how to get across and still allow ice to flow underneath? and for shipping to continue? it would be possible to build the sections in a dry dock and float them out to site? or if more remote? use aerodynamics to help out? by flying the bridge section into place? they are sort of an ready made aerofoil? there are thing like vtol? variable vector controls? just Iāve never seen it on a massive scale? so peeps? that just a little take on it from my end of things? there is scaling potentials? @AndreasEisele @Windy_Skies @tallakt @gordon_sp @batlabat @Rodread @PierreB @dougselsam
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Custom made AWE per site is a limited market so that could be a reason it did not attract venture capital. I hope that the AWE community doesnt end up destroying a monumental piece of nature like the grand canyon.
That all being said, there could be enough places where some small scale AWE could make sense, like bridges maybe?
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Custom doesnāt have to be difficult
An automated process from a parametric design model can belch out custom fit without modification on modular parts
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agreed lads.
with lazer scanning be a wildly used tool now days. there would be a high degree of accuracy? especially with custom fits? im fairly sure the (scan Britain project)? has some the required data? something the OS did? as it was their job to go around scanning monuments and anything of historic value? it also heavily use in the up keep of many bridges? i know hampshire county council had a unit? because during the design phase of the replacement holmsley bridge. they model the site before had to get the measurements? even it it was a simple lazer reading at given points? ive heard of drones being able to this task? which means that with a few quick passes you have all the data set you need? lazer scan technologies being even used to detect flaws in the structure and recommend actions? Iāve even heard of radar being used? because its able to generate a 3d model. with it even being able to show material thickness? not quite at scan pyramids level but still fairly handy to know? it generally exploits the penetration depths of certain wavelengths? there was talk of it when i was in college? so the scanning tech has been about some time has been bout some time? i dont know if you might be able to find what is required on Archie maps? which is lidar data base? it was good at pointing out hidden feature in the landscape? it showed several thing in my area? potential site of interest archaeology wise. had a bit of a barney over it with remote sensing? because i swore i could see where a roman temple complex? in bisterne manor? there was also what also looked like a motte and baily castle from near Colehill in Wimborne? and even the foundation trenches to the priory on st catharines hill? on what looked like an odd axis? it might of even had an apse? folk law in my area goes into that one? and attributes it the the Christ man himself for why the priory didnāt end up on a hill overlooking two valleys? still it does sit on the fault line? so that a quest some other might like to ask? why churches and fault lines go hand in hand? colonge cathedral so different? i digress? remote scanning is an awesome technology! definitely handy if awes need to dip its toe?
i would guess that there would be a long term bonus to taking the bridge approach? one being lower maintenance costs on modular component due to a longer life span?
i know there is alot of grumbling over turbine towers being only fit for x number of years? 20 - 30 year at best? before structural fatigue set in? as those thing are radiculiosly expensive to begin with? you want something that going to last longer? and use fewest materials? my closest viaduct not in use is the borne valley road viaduct? formally served Bournemouth west before beeching cuts? it can be a site for urban explores to go have a poke at? ive been there when the odd gust would either take you of your feet? or cause you to swerve on a bike? the wind runs right up the valley most days?
fairly sure there room for improvement? also give people the opportunity to survey structure like this? effect repair where required? many of the arches are of quite a span? as they do cross a local road? the a few feet tall? if i recall correct the the tallest spans about 130 foot? there 10 spans to get across the valley there are plenty like this up and down the county? ours would only possibly take a few turbines? sure to near by housing? this is just an example? you do have more remote ones? which wouldnt make some shudder at the thought of a retrofit? i am disapointed with wikipeadia as it seams to be missing a few of the viducts and bridges? so dont take the next like as gospel? List of railway bridges and viaducts in the United Kingdom - Wikipedia it does kindly mention the one that were demolished?
if this was a few year back i might be suggesting old mill chimneys? who donāt love an old steeplejack? but as many of the old mill chimney met with an un-ceremonial end? they prehaps not best for AWES applications? though seeing one of rod turbines on top would have been quite something? just another idea in the cooking pot to consider? i have see suggestion for incorporated turbines between sky scrapers? considering that some street make a made made valleys? it a problem in some cites. there have been reports of people being injured after being swept off their feet? it does get a mention on the incredible engineering blunders fixed? plenty of design consideration?
even if you were to clad the inside of the arches with a custom style areomine? with a turbine house in a set of arches? your may still face an issue with how do you keep boot firmly planted on the ground? at the same time of generating electricity? it one i have thought a co flow design would work rather well? expanding on the co flow shelf idea i had? multi vector strategy? could work well? it not just rail bridges you have many type that could be useful for suspended awes? even something like rotor wing to move through the vortices? created under the super structure? might also do the job? when i was toying 3d print? it had occurred to me then how easy it would to use wind shear to power a turbine? plenty of option should that road be travelled?
@AndreasEisele @Windy_Skies @tallakt @gordon_sp @batlabat @Rodread @PierreB @dougselsam
then its all about companies who maybe able to assist in creating the final product? for me that an all hand on deck? then let see where this goes?
i know this is something many here would be interested in? there plenty of rivers this can happen in? they would have to be away form main navigations? but as you love the kite that doo this? with a turbine at it heart it something that can work in both mediums. if you connect in series you can up the anti with green tech? some where where you have a wide river and high flow? you could have one in every river? this examples from Sabogawa River in japan. i see the potential of arrays like this? this would be something like a kite barrage? or kite train? the bonus it would be cheep and low impact. it would fit in with suspend types of AWES.
i can imaging the grand canyon crisscrossed by these. both airborne and submerged types? if you wanted simply beautiful? then tis is one way to go? plus if the mouth is wide open? held open with some like gravity potential generator like Iāve have postulated using? everythingās gravy lads! could look something like this? but really down do every individual creator/maker?
retail for these I would suspect to be in the region of Ā£500 per unit? if you have 1000s thats a lot of energy?
bonus is less damage with birds/fish and all other wild life. if you want amazing? this would be one way to go? it might also work for tidal power? as it self orienting with the flow. it would be less likely to become damaged by debris? if that the case? then it could see wide spread roll out? instead of months development you talk 5 min of plug and play then your way.
this might also interest local authorities? because of adaptability of the design and potential for upgrade and refits? all depending demands of the system? it can be completely recycled or reused in another location. which ad to economic longevity. if you spend Ā£500 it last 100 years? Ā£50 a year is good economy per unit. there is plenty of room for manufactures to get involved. i know Donald trump was caught saying he hates the current turbines. when asked about king Charles 3rd eco agenda before tomorrowās coronation. if AWES could get someone trump on side? the would be huge? usually if it make sense to him? then it will make sense to more business types? Iām not an huge estimator. but my reckoning suggest there a billion dollar market to the right customers? so there my take, any wishes to chime in, please do?
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From https://www.mindmeister.com/132484153/awe-map?fullscreen=1 at the bottom of the page under auto-zenith:
fyi it popped in to the feed today. curious i took a gander at it?
looks there a few thing that might pan out here?
he says 80% efficient due to how much energy is transferred to fly wheel?
i reckon you cold get more? maybe as high as 95% as is nearly a Francis turbine for wind.
i leave this here,so people can make their minds up?
if you care about those sort of thing? you have to remember not everyone does as he does. he not doing it to be smart or clever. he doing to have a bit of technical fun. production and design channel it ok? it not top brass sure. get you bet it what are you after? maybe i want a broad scope? that dont make me stupid? maybe unaware? not stupid. may not be the greatest of the best? but heās making things. he does take a critical view and admits he can be wildly off an times. even says try for yourselves. why is he wrong? if wind energy is all about how efficient you can covert airflow in to work? i mention a while back something about the mass of the rotor need to proportionate to the mass.? volume of airflow.
i believe it was you who mentioned that air flow donāt stop when it hit buildings? so it how to manage the flow? he showing one example? i donāt take everything as gospel. if it genuine that cool? if you donāt stop the wind from moving then you have high efficiencies? does it beat the betz limit? ok @Windy_Skies why will any one know less? if your not try to gain much? just watch some guy make thing what the issue? your more than welcome to prove him wrong? he open sourcing this so you can go to his tinkercad and print his files? should you want to? why is he wrong? he know ther are thing out there he need know more about. that why he running open source for inputs? you welcome to point him the way if you know any better? so is he wrong this time?
Heās not breaking Betz's law - Wikipedia. He has no regard for the truth, that makes him a bullshitter and with that the exact wrong kind of person to follow if you want to learn stuff. Heās filling your head with gobbledygook.
If you have a result like that you donāt go thatās interesting, anywayā¦, which he does often the times I managed to suffer through part of another video of his, you go hmm, where did I make a mistakeā¦
The video could have been a nice intro on how to better measure wind turbine output and his struggles to get more accurate results, from which we could have learned something. Instead we got this. Donāt waste your time with rubbish when there is so much content available that isnāt rubbish, again, for the love of fuck.
Any comment of yours that includes a link to his videos gets an automatic down vote from me.