Windmills Are NOT Like Dams
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- Опубліковано 31 бер 2021
- Watch the bonus material cut from this video at nebula.tv/minutephysics
The Solution to the Windmill Paradox. This video is about the tradeoff of Windmills: the fact that the more kinetic energy you extract from the wind the slower the wind goes, the less wind you have to extract energy from, etc. How much energy is the sweet spot to extract from the wind??
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"uploading a serious video on april fool's is a fool's errand"
- Tom Scott
xnopyt.
*AAAA*
Also Grimm Drip.
@@captainnomekop5056 !!!
did he actually say that or is this just a made-up quote?
Good april fool's day video considering windmills are giant fans, and they are responsible for all the wind.
@@mikefrommiami yes, wind didn’t exist until the 7th century, when the first practically usable windmills were invented in the persian empire.
Damn never knew....
damn it, those people just won't stop making typhoons
Duh.
WINDMILLS DO NOT WORK THAT WAY! GOODNIGHT!!!!
The best April Fools joke is one that makes you think you're being fooled when in fact you aren't.
The best April Fools joke? Fear.
How much wind dose a windmill mill when a windmill windmill mill
And this is why April fools sucks
yeah I also expected it to be an april fools.
I'm one day late but... same. I looked at the date and thought to myself "this could be a prank"
I have actually learned it in college last year. You used two minutes to explain two whole lecture's knowledge. You are a legend.
Fun fact: All minutephysics videos are so awesome, it only feels like a single minute when you watch. It’s the most enjoyable kind of time dilation.
YES!!!
Content of the video is just over 2mn, which is insane to explain so much!
🤓Umm, ACTUALLY That's why its called "minutephysics"
For the whole time I kept thinking 'you are hiding the april fool's part way to well, people are going to actually believe it if the rest of the video is making too much sense'
How much wind dose a windmill mill when a windmill windmill mill
Wait, what is the joke? I'm actually seriously confused. Is all of this lies or the truth?
the april fools part is implicit, the fact that you spend more money to keep the windmill working than what you earn from selling the energy.
windmills are just machines that convert money into energy !
I can't make gramatical sense from your tongue twister. I propose: How much wind will a windmill mill when a windmill will mill wind?
@@monad_tcp : It's cheaper per kW than a conventional plant. They're putting the things up because it lets them delay (though not avoid) the expensive expansions.
Actually had to study this in one of my majors while studying Mechanical Engineering back in college and this video summarizes and explains this stuff really well!
Indeed! Even much better than that Dr. Prof. Ing. habil. Pleasemakemyweinerhard in my university, who cannot go 5 seconds in a row without having to catch a breath and make that annoying tongue sound, instantly failing at explaining the course.
I'm an average guy with no real academic degree or whatever...but... my thirst for understanding physics grows with every video i see from this amazing channel..
Thank you sir.
you can get a REAL academic degree if you want to... part time study
or take online courses for free!
@@rickkwitkoski1976 thanks for the advice....👍
...thing is that.... well... let's just say that... mathematics aren't my forte.... I've always had trouble with numbers and calculation...and oh god algebra its the freddy krueger of my nightmares....😔😟
Soo when I discovered this channel my hopes of at least understanding just a bit of physics went through the roof.
💯😎
@@kkattavega117 May ur freddy krueger turns into Tom and jerry of ur dreams.
@@BrainPermaDeD 🤣😂😅😁👍
Can anyone join me who is interested please 🥺
I'll be very grateful to you 🙏
This is something I had to learn during my Aerospace studies regarding propellers. It's the same, but the other way around.
Thank you for keeping me from not learning.
But are you really not learning?
@@ervinm.5065 At school, I already know everything they teach. I only learn from videos like this
well, those in Oklahoma may have learn something about windmill: ua-cam.com/video/nSb-33aXK3E/v-deo.html
He is the one of those who uploads video which I can't see in 2x.
1.25x usually does it for me.
Can confirm
@@morkovija I also usually run everything 2x, but sometimes there's these extremely well condensed videos where you need to jump out of warp speed to enjoy them fully.
@@KKdessu I never understand the physics anyway I'm just here for the weird facts
I'm not a native speaker and for me it's not easy to understand him in normal speed, i have to go back 5 seconds often and every time it feels like i've gone back half of the video 😅
Been following your channel since my high school physics teacher introduced the class to your videos over 10 years ago… every week we got to spend the first 2 minutes of class enjoying your videos… glad you’re still making great content
I appreciate that nod to the complexity and the book pages at the end.
This brings back memories about how I found out about this figure.
When I was elementary school (15+ yrs back) I really liked to make windmills from wood wings (like 1,5x5 cm wide wood-piece and with knife/polishing making somewhat triangle from that with smooth "catching" edge and rounded back for light-weight and more "efficiency"). Three best examples had 3 wings (~0,8 m long each), 3 wings (1,1 m each) and my best - 5 wing (1,2 m each) design that worked at lower speeds than 3-wing (it was located low to ground with uneven terrain/trees around so only 1 lower wing (with 120 degrees between) had trouble to keep speed up and it lead to vibrations. 2 lower wings (with 72 degrees between) solved issue and it was smooth and worked as expected. And it was this time when got to figures how wind speed impacts power (not sure how precise but from that time used m/s^3 = W/m2 formula whenever wanted to know how much power windmill actually can extract - and that "nominal" power was based on ~9 m/s windspeed). And how efficient it can get (figure in video) etc.
glad to see you posting again
great video
So a legit video. Apparently cut content - nice!
Thank you.
This couldn't have come at a better time. I'm doing my final year dissertation right now and a section of it is about windmills and energy extraction. This helped me a lot with understanding it better.
What will your degree be in?
Mechanical Engineering
Hang on a sec. You're doing your dissertation on this subject and you didn't know and have full understanding of the basics of the subject already?
@@salerio61 No, my dissertation is on creating an energy efficient home via green energies/technologies. But I haven't touched wind energy in 2 years (since 2 year).
For one of my 2nd year modules I had to design and manufacture a 9 foot wind turbine, so I understand more than just the basics, but its been a long time since covering that, so this video was a good way to essentially refresh my memory. I had a lot of "Ah ha, I remember this" moments in this vid. Hope that clears things up.
The problem with windmills is that when the wind blows in the opposite direction the blades turn the other way and suck electricity out of the grid.
So when are they going to use Diodes?
@@haroldbn6816
What's Welsh people git to do with it?
😁
@@awatt Iam at loss here did I somehow involved the Welsh!!!
Dai Ode and his sister Cath Ode.
Sorry couldn't resist it.
Just putting a marker here to note that the vid and this comment went up on 1st April 2021.
Brilliant! I was gonna make a video about this for my Power Systems students, but now I just have to give them the link to this video!
#notPlagarismBecauseYouWereMakingItAnyways
Great content as always! Though the "solution" in the title actually had me hoping that we were able to surpass the 59% limit! Looking forward to your future videos.
Bruh. Seriously? I never had that thought.
@@BrainPermaDeD Alright lol
Wind...Mill? Behold, sciences latest triumph over wind power - the Windlathe!
Betz's law! Finally I know where that 'magic number' comes. It's quite familiar for mechanical engineering students who studying fluid dynamics
I learned more from this channel than all my online classes combined.
then listen to the classes lol
same goes for probably all the students who went online.
might seem complicated at the first time to me, but it's well explained when replayed. I didn't know I can catch up Betz's law in 6 minute. Thank you
A corridor crew video from 2016 brought me to this channel. Thanks Wren.
Same
Awesome explanation on Nebula! More please, my fellow Physicist!
Wow sir, how did you make this video, without you actually showing yourself onscreen, in the sense your hand!?! Beautiful !
This is a good explanation of the math in Betz's paper! Do you think you could do a video on Betz's paper on multiple rotors?
I was hoping for an April Fool's joke
Same
He did say at the end that "this might be off" lmao.
@@thejuice027 that's not a joke though, just a statement on how practical isn't as efficient as theoretical
@@stinkytoby Maybe you just don't get it, I think it's pretty funny to watch the whole video just to hear "this might not be 100%" at the end. Made me laugh.
I'm already a curiosity stream and nebula subscriber, it would be really cool if you gave us a direct link to this video on those platforms, so I can pop over there and see that video without having to search and find it
Please go more in-depth on the energy differences of drag based windmills vs lift based windmills
Amazing video!
i'm kinda disappointed that i learned something on april 1st
- Making video to explain interesting PrObLeM then do it with the speed of light is a pRoBlEm itself .
- Compressing information to produce a short video that sAvE TiMe made me pause/back a lot in order to catch up , which wAsTe my time any way .
- It is not about given an information , it is about how to present it .
~ keep up the good work , thank you
Didn't know I needed to know this, but I'm a fan.
Ah, I see what you did there :)
Man..you're just blowing hot air
In the first clip of the outflow pipe moving up and down the side of the reservoir, you say that you can lower the water without slowing the flow, but wouldn't lowering it increase the pressure and make it flow out faster?
Great video, thank you.
Could you, maybe next time, also share references to the papers/books you are using in the video?
Chreers
I want to thank you for not uploading an April fools video
Very short, very interesting! I feel like some people may have gotten lost cause of how fast it was, but I was fine (granted I'm a physics and science ed major...)!
0:54 , 1:36 , 1:40 There's an error :
it's not "wind volume" but "wind section" or "wind area" or "closed surface" in mathematics. (in fact, saying "volume" is absolutly wrong, volume per second is actually constant, by conservation of mass)
Plus, you showed why speed at the mill was 3/4 of in speed but not why it means 3/4 of wind in SECTION(!!!), on a slide that titles "conservation of mass" but doesn't use it.
Explanation :
flux formulas :
flux (unit/s) = j (unit/m².s) . Surface (m²)
j (unit/m².s) = density (unit/m³) . velocity (m/s)
( "j" is "flux density" but I wanted to keep one word per variable)
In the case of a windmill, air compression is negligible, so there is no noticable variation in density. We'll consider density as a constant D.
Thus,
flux = D . velocity . surface
For a given flux F, in other words when you conserve mass (or electric charge or "unit" of any quantity), an increase in velocity means a proportionnal decrease of surface. Proof :
F = D . v(a) . S(a) = D . v(b) . S(b)
or more interestingly
v(a) . S(a) = v(b) . S(b)
or in an other form
v(a) / v(b) = S(b) / S(a)
if
v(mill) = 3/4 . v(in)
then,
v(in) . S(in) = 3/4 . v(in) . S(mill)
=> divide both equation members by v(in) =>
S(in) = 3/4 S(mill)
◻
PS : at 1:05 , 1:18 , "as much wind to pass" is given by wind section S(in), not wind velocity v(mill). Yes, it's the same proportion, but mixing surfaces and velocities has no sense... It's like saying a bottle of water has a mass of 1L. Yes, 1L of water = 1kg. But 1L is not a mass!!! Don't mix speed and cross section even if you fall on good numbers.
Hey the videos you make are dense packets of information and are awesome , but here you have just given the explanation for Betz limit right?then how is it a solution to windmill paradox? Or is it just a way of putting content related to April 1?
Ah some minutephysics😃
How much wind dose a windmill mill when a windmill windmill mill
thought it was gonna an Aprils fools video and was waiting the entire video for the nonsense to start
I was partly wondering if this would be about how much grains they could mill, and partly how much they should be allowed to tumble around over the countryside (not on the post, much like a big loose wheel).
minutephysics: Posts a new video.
Almost Everyone: Go straight to the comments section!
On the plus side, this act greatly appeases the algorithm god.
It'd be very nice and handy if the Nebula video was linked in the description.
@minutephysics I really want you to explain CT clamps on AC circuits. How can an RMS value give a direction on the current. Please investigate.
I wish the winds around the region I live could be reduced a lot.. here we even gave a local name to the wind that hits this region of Spain.. It is called Cierzo and it is quite strong, a lot of windmills could have a lot of benefit from it and ease on the wind that hits the city.. haha that would be nice..
Can you make an updated version of your time travel video with endgame, dark and tenet time travel system?
So in the city could a build have windmill floors basically windowless floors funneling air through, would that also help in reducing sway allowing some air to flow through instead of just crashing into.
What are those scientific papers you cite/show ? Why doesnt the description mention and link those, such that we may have a chance to try to make those computations by ourselves? Im sure the math involved is intricate
There was a point where I think you could elaborate more at: when saying that lower speed means the windmill extracts energy from "less" wind, I had to think pretty hard to realise you meant "wind of constant density"...
Can you link the nebula version in the description? Very annoying to have to navigate to it. Also annoying to find out there is an extended version of the video on Nebula at the end after I've just finished watching this version.
Could you please make a video of how does a gear work or how does the engine work
Forgive me if this is a dumb question, but why would we care about the efficiency of the energy extraction - i.e. isn't more energy farmed always better? Why do we care about per unit wind when there's an abundance of it, it's not like there's a problem with taking as much energy out of the wind as possible yeah?
i just noticed a math thing and i’m wondering if there’s a reason for it. ex, 7x7 is 49 and 6x8 is 48. Add one and subtract one from each side of equal products and the answer is always one less than the equal products. Is there a math principle for this? an explanation video would be awesome!
and if you go out further, it’s still consistant. ex, 7x7 is 49 and 5x9 is 45. All other permutations of -2 +2 have a difference of 4. -3 +3 is a difference of 9 in all cases and -4 +4 is a difference of 16. the differences are all square numbers, I’m assuming it continues that pattern indefinitely. it also works with negative numbers. ex, 2x2 is 4 and -1x5 is -5. The difference is 9. I just discovered this and it’s blowing my mind. Could you help me out by telling me someone discovered this 1,000 years ago or something
@@jarethculwell2013 Say the original number is m, and you change them by n,
The difference is then
m^2 - (m+n)*(m-n) = m^2 - (m^2 - n^2) = n^2.
This makes me really wonder, if humanity completely switches to wind power, would that actually influence the climate through slowing down winds???
Yes, everything in excess will kill us.
@Alexandr Semydidko It would, under ideal conditions found only in marketing brochures and activist blogs, but the reality is that for every unit of wind power you build you need at least one unit of inefficient fast ramping power. It just doesn't make sense from a grid point of view to compare consistent reliable power to something that depends on ideal weather in remote places.
At the moment of power production, sure, it might be cleaner, but if you take the whole infrastructure and ecosystem into consideration renewables are just a massive grift by the gas industry.
probably, but so does cities, forests and mountains
@@darkwingscooter9637 Until battery or other storage technology catches up, you mean.
@@JeffreyBrandtLaw The problem is that it needs to be twice as good as nuclear (I'm not advocating for coal here). You are generating power twice: First with the windmill or panel and then again from the battery, with a storage step in between.
Fossil fuels have a leg up because they are, for all intents and purposes, a highly refined, concentrated, and efficient battery that gets used up as it it drains. The fact that there is so much of it means that the the fact that can't be refilled easily is not so much of a problem.
But the initial generation stage was taken care of by the plants, hundreds of millions of years ago, and the storage part by time and pressure.
That's why the comparison between renewables and fossil fuels is misleading and ends up being nothing more than a marketing campaign for gas companies who end up supplying the balancing load. Why do you think oil majors were so keen to jump on the greenfacing bandwagon? They are the ones making bank off of renewables and climate change hysteria. It's counterintuitive, I know, but it's the only way to make sense of it.
Think of it this way: Who really benefits from artificially higher prices if the competing product doesn't really compete and is physically incapable of being a true replacement?
Great woooork 🥳🥳🥳 Thank you 💜💜💜
So i got an important question i need answered.
I read in a few pages that apparently either exists or will exist a type of computer that will run instead of on 2 stages, on and off, with 3 stages, on, off and in between, called quantum computer. If such thing is the case, could we use the principal of teleportation to transfer internet globally at the speed of light without cables? Could we do it with the internet as it is? I hope this makes sense
Hi
We can already transport information at the speed of light without cables using electromagnetic radiation. That's the principle behind satellites.
Also, I don't know a lot about quantum computers, but I think that they don't have much to do with speed of light, so they shouldn't improve much the speed at which information travels (other than maybe being more efficient and fast on solving the cryptographics algorithms neeeded to stablish a safe connection)
POV: You're getting flashbacks of sitting in class and you're the only one who doesn't get it, because the pace is too fast for you
Big fan from india
Windmill from India? 😋
I wish my physics lesson was this short and understandable
Please put a link to the extended Nebula version in your video's descriptions. It's pretty annoying to have to navigate to it (Nebula is slow...)
I actually knew it was about 60% because a friend of mine did a science fair project on it back in highschool (he mounted different windmill designs on top of a truck, it was pretty cool).
But actually this number doesn't matter that much because windfarm windmills actually extract a lot less energy than this, partly because this works for single windmills but doesn't account for several windmills lined up behind each other.
That's why the windmills aren't exactly behind one another in wind farms, but rather they're spread out.
Windmill Energy Conservation, 56.25%
HD TV 16:9 aspect ratio, 56.25%
We need windmills to power our TVs.
The most you can mill from wind is 100%. With a type of mill called sail.
Only if the sail is infinitely large. Real sails "spill" wind around the edges, just like windmill blades.
@@dlwatib it was sort of a joke, dude. It's not that simple, and you can actually sail around 3x faster then the windspeed depending on your rig (and where the real wind is coming from). That still doesn't mean you extract 300% of the energy from the wind though.
The best part is when I had to skip back several time before finally realising I still have no idea what is going on.
2 uploads in one week? From both Veritasium and Minute physics??
I can't make a joke yet, the video hasn't even started
Hearing "Three Fourths" just sounds so alien to me.
We say "Three Quarters" the same way someone says "One Half".
I hope no one says "One Twoths" or something silly like that.
It would be a "second"
@@phosphorus4 I did think that, but thought it was already confusing enough and didn't want peeps to mix time version of seconds into the mix
I can't believe this video is not just a bunch of hot air.
This is called the Betz limit, named for the German physicist who published the mathematical proof in 1919. The magic number is 16/27.
I had never thought about wind volume… that's wild
0:09 thats not entirely correct... The flow pressure is proportional to the outlet's hight, and if im not mistaken - therefor the velocity. But i get the point
Wow, someone gave a thumbs down before it's even started!
Haters are everywhere!
All good points.
Since he was not given credit in the video, the German physicist Albert Betz did the necessary research and math to calculate these limits.
How many birds and bats can a windmill mill?
Fact: Dead bats are found beneath wind turbines all over the world. It’s estimated that tens to hundreds of thousands die at wind turbines each year in North America alone. It is the pressure change--not the blades--that wipe out thousands of bats annually at wind farms
Do windmills have adaptive systems to deal with changing wind speeds?
I love to study physics but I generally gets stuck with lack of formula on the needed time and sometimes I get frustrated by the calculations. Can you help me❤️❤️
I liked the first title of "how much wind should a windmill mill"
as the saying goes
How much wind can a windmill mill if a windmill could mill wind?
It would mill as much as it could if a windmill could mill wind
or did it use woodchucks?
Why does this feel familiar. It says it was uploaded yesterday, but either I've seen this video before, and recently, or someone else made a very similar video very recently.
Isn't this called the Betz Limit ? What about vertical axis wind turbine ? Does this limit apply ?
What i heard was: How much does windmill mill the wind when windmill mills the windmill and windmill slows down.
Love From India🇮🇳❤️
Assuming that both dams and wind turbines are used to generate electricity, don't dams have turbines at the bottom to convert the energy of the falling water to electrical energy? Doesn't that mean the turbine also needs to slow the water down like how the turbine slows down the wind? I mean they're both fluids
If run at 2/3 energy extraction, or 59% efficiency, how often does the blades leading edge need repairs, if run at a lower efficiency rate does that increase the lifespan of the blades before repairs are needed and if so ...by how much, and what's the downtime + expenses going to *drag* (sorry) the overall expenses vs. rewards for the windmill?
Like you said, windturbines (aka windmills) are endlessly complicated and anything from atmosphere conditions to shape of blades will impact the overall durability and energy efficiency of them. All of this without even considering the impact on local wildlife and its people.
Exact name for this is : Betz's law. From Albert Betz.
I figured it out after he said there is more in depth parts to this
“WINDMILLS DO NOT WORK TGAT WAY! GOODNIGHT!! “
I always wonder if slowing the wind any effect on nature? Doesn't nature need winds in order to survive?
We need a video on the muon g-2 results
a video on MUON G-2 experiment please🙏😀
Me: "How much wind could a wind mill mil if a wind mill could mill wind?"
MinutePhysics: "Well looking at the math, a wind mill....."
(3:02 minutes later...)
MinutePhysics: "...and that's how much a wind mill can mill.)
Me: "Math... so much math. B-r-a-i-n H-u-r-t-s..."
Minute physics is galaxy brain
For hydro dam exist maximum peak value but also minimum 0. For windmill blades it is u=v0/2 is maximum value for specific blade angle. That is different because u=v0/2 is fundamental law you can not increase what value where for hydro is optional, closed turbines steam, compressed air hydro turbines operates differently from open air windmills here angle of attack of blades is more important and exist one unique.
i don’t really understand anything he says, but it’s still hella interesting
Title: Windmills Are NOT Like Dams
Me: No shit
**Presses replay and sets speed to 0.5x**