Why Do Wind Turbines Have Three Blades?

Real Engineering
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There is a lot more to this subject than I have covered in this video, this is just the basics. I have used the Wind Turbine Handbook as my primary reference material, it covers pretty much everything you need to know about wind turbines. If you are studying this subject academically I highly recommend it. You buy it on amazon here: www.amazon.com/Wind-Energy-Handbook-Tony-Burton/dp/0470699752
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My Instagram: instagram.com/brianjamesmcmanus
Thank you to ruvid.net/u-Kristianpont
For allowing me to use his sound record of wind turbines
Stock footage sourced from videoblocks.com
Once again thanks to Bensound.com for the amazing royalty free music. This time I used Bensound - New Dawn
[1] Page 340 Wind Energy Handbook - Tony Burton

Published on


Apr 22, 2016




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Comments 80
Real Engineering
Real Engineering 2 years ago
I plan to remake this video at some point. It's a really shallow explanation. I simply did not have the skill and experience to make a longer video when this was released. I could crank this video out in a single day now. The subject definitely deserves a more in-depth explanation.
Jennifer Taylor
Jennifer Taylor Month ago
Real Engineering your really smart
Siddharth Sharma
Siddharth Sharma 2 months ago
would like to see the new one for sure.
Hermann Rochholz
Hermann Rochholz 2 months ago
@Glenn the Geeky Hippie They are also painted light red. Use light colors (correct english?).
Glenn the Geeky Hippie
@Hermann Rochholz Gotcha, and thanks for the quick reply! That's too bad, because I was imagining alleviating the "eye sore" issue by painting them bright primary colors (or even lighter, more pastel colors), essentially imitating gigantic flowers. (I'm big on bright colors as I tend to wear a lot of tie dye shirts, its kind of my trademark). Guess materials scientists need to get on the ball and develop something that can maintain the proper temperature and tensile strength/stiffness needed while not being such plain or drab color.
Hermann Rochholz
Hermann Rochholz 2 months ago
@Glenn the Geeky Hippie Hey - a good question is as good as a good answer! Yes- they have to painted in white or light grey: They are built with plastics. And plastics has a "transition temperature" ($T_G$). This is the temperature when it loses its "stability" resp. physical features (stiffness....) . And when you paint them black the temperature is significantly higher. Everything is woven in wind power. It's relative simple - but connected.
Shad3w Gaming PL
I saw alot of wind turbines with 2 blades
Roland Mousaa
Roland Mousaa 2 days ago
Thanks for the info.. smaller blades..
Wizard Nerd
Wizard Nerd 4 days ago
I ate a wind turbine
Dave 7 days ago
Maybe you could explain to us why AU Optronics "shelfed" its patented U.V. solar panel that's 10 times more productive than a photovoltaic.
Parrot Brand
Parrot Brand 29 days ago
Does a wind turbine with 3 blades rotating at 2 rev per sec hum at 6 Hz or 2 Hz??
MrSummitville 22 days ago
The blades will go past the pole at a rate of 6 blades every second. It is more of a swoosh sound, than a hum.
bhoom bhoom
bhoom bhoom Month ago
Devansh Trivedi
Devansh Trivedi 2 months ago
Then why not use vertical turbines.... aren't they more beneficial as they can react to winds coming from all the directions
MrSummitville 22 days ago
NO, VAWT are less efficient ...
Salila Ranjan Sahu
Salila Ranjan Sahu 2 months ago
Just don't do videos for the sake of it... If you can't explain just don't..
WIE110 2 months ago
Bad explanation.
theklrdude oo
theklrdude oo 3 months ago
they have three blades because : 4 is too many and 2 is not enough !
dimitri motor
dimitri motor 3 months ago
3 is really fast turning 5 was for more power but even more or 5 or 6 then you quickly lose he slows down to power and air release and that was used to pump water in the farwest that was then a crankshaft with a tube the to pump water out of the ground
dimitri motor
dimitri motor 3 months ago
the noise that you hear occurs from wicks that pass read the support post
Tech2 3 months ago
Open the following store to download best Renewable energy books. payhip.com/RenewableEBooks
Jeffrey Kemper
Jeffrey Kemper 3 months ago
The high torque from being too long is why your blades failed and will keep failing. You should of went with more blades and shorter to handle the torque. You can make the blades thicker but then you will need a stronger base. Or you can just do the sensible thing and mount it on the ground instead of way up high and run it off of a semi truck diesel engine and transmission 18spd. Automatic to power the gearbox and generator. It can do it for the mega watt or tera watt output. If a locomotive could run off of 3 semi truck engines. This could too safer then with blades. Plus, the output off of the turbine could power other electric/ hydraulic powered wind turbines. Each putting out a mega watt or tera watt each. All of 100,000 watt motor. I gaurantee it will work for you. Soon you could be putting out the equivalent power of a nuclear reactor power plant or larger. I also gave ideas for how to boost the output of Herbert Hoover Dam to 1,000 times more output.
Zeratul297 3 months ago
Is that an old wind turbine? The ones around here are super quiet or just way too high up
wes monk
wes monk 3 months ago
Why not just make smaller ones...or a vertical wind mill.
Brit Hey
Brit Hey 3 months ago
The best design is zero blades. You dont even need a generator or tower. The savings are enormous. Birds like it too.
dougselsam 4 months ago
Here's the real explanation, from noted expert Mick Sagrillo: "When the blades of a two blade rotor are lined up vertically, they offer little resistance to yawing motion. However, when the blades move one quarter of a turn and are in a horizontal position, they exert maximum resistance to yawing. This continuous shifting of resistance to yaw jerks the wind generator as it hunts the wind. These vibrations eventually degrade the entire system. The inherent imbalance of a two blade rotor is totally eliminated by adding a third blade."
Ray Rowley
Ray Rowley 4 months ago
1:50 annnd now I have cancer.
luigi ionascu
luigi ionascu 5 months ago
_is not good resolv the this probllem _the power of wind against fly pale of turbine is more most with number pale fly _archaicxn lord
Joshua Kiser
Joshua Kiser 5 months ago
I see references to increased power production but slower speed with higher blade counts, I am trying to build a small 1-2 KW wind turbine for battery charging. It says lowered top rpm, which I am interested in. High speeds usually mean high and damaging voltages and burn stators. Has anyone found any reference to how much it reduces rpm? 10-15 mph is what I am optimizing for and I can build the permanent magnet generator to match the torque and rpm. I was considering as many blades as possible. 20 if I could, like an old water windmill.
MrSummitville 22 days ago
A 20-Blade Wind Turbine is not very efficient ...
Ghost Mountain
Ghost Mountain 5 months ago
3 blades make them more efficient bird killers.
Core On Crack
Core On Crack 5 months ago
Doug Grinbergs
Doug Grinbergs 6 months ago
2:19 catastrophic turbine failure!
Anton Qvarfordt
Anton Qvarfordt 6 months ago
Why three? Because it's optimal... I did guess that actually :P
Earn Do
Earn Do 6 months ago
3 unit x 4 blade VS 4 unit x 3 blade, which is cheaper ?
Skill practice
Skill practice 6 months ago
Hi my name is mansur muazu but i didn't know the reason why you don't use tell us your name at least in one of your videos even i the introduction. I have a question to first what is engine control Unit (ex) that is used in most of the petrol cars How is it recognize sensord key without internet connection. Second what is valve and what is the fundamental difference between v8 and v6 that is mostly written at back of cars like Toyota highlander. Thirdly: how CDI work. What is the purpose of adding it between starting coal and body coal. how CDI convert starting coal power and pass it to body coal and from body coal to spark plug.? Thanks
Brandy Ellis
Brandy Ellis 6 months ago
Doug Selsam
Doug Selsam 6 months ago
The real reason two-bladers are seldom seen is they rip themselves apart whenever the wind changes direction (yaw). When the blades are vertical, the turbine can change direction easily. When the blades are horizontal, it can only change direction with great difficulty. That pulsation, twice per rotation, rips apart the turbine. Teetering hubs help, but the problem is still too bad to use only 2 blades. a 2-blde rotor is only blanced in 1 dimension. 3-bladers are naturally balanced in 2 dimensions. 3 blades run smooth when changing direction. 2 blades not so much. I build a lot of 2-bladed turbines, but using multiple rotors on a single very long driveshaft, they do run smooth for me. Otherwise, with a single rotor, I have confirmed, the turbine life is limited to only a few years with 2 blades.
Candy Neige
Candy Neige 6 months ago
In my home town (Which is Chartres, FR, European Union), the energy here is powered by wind turbines.
Savage Dragon
Savage Dragon 7 months ago
Hmm in my country there's an inventor who wants to revolutionize wind turbine designs. He claims that it's erroneous to apply Albert Betz' law, which derives itself from Newton's 2nd law, to wind because wind is a fluid and since Newton's law addresses particle dynamics, you'd arrive at wrong conclusions by using Betz' formula. Here is his statement in his newly claimed patent: patentimages.storage.googleapis.com/57/1e/70/a6c6bbafdf89e4/WO2016011462A1.pdf. Do you have any opinion on this topic?
MrSummitville 22 days ago
Newtons 2nd Law does apply to fluids ...
anth benit
anth benit 7 months ago
magnetic braking?
Jarome Jacksan
Jarome Jacksan 7 months ago
im sure you'll build it yourself. I made it 2 weeks ago thanks to Avasva website.
Gary Hawkins
Gary Hawkins 7 months ago
0:19 The 18 blade units on farms pumped water mechanically I believe. Those would provide a lot of torque at a slower speed, it's a complex topic.
MrSummitville 22 days ago
@Gary Hawkins Go ahead ... make an 18-Blade Wind Turbine and then you can tell us how *INEFFICIENT* it is compared to a 3-Blade Wind Turbine.
Gary Hawkins
Gary Hawkins 22 days ago
It relates to impedance matching, maximization of power transfer. This is in that same area: ruvid.net/video/video-1Pd0lUKWe7o.html Just showing that it is not a simple matter.
MrSummitville 22 days ago
An electric generator is better with higher RPM, not lower RPM ...
Antonio Amigo
Antonio Amigo 8 months ago
100k for a blade? no wonder why wind power isn't popular. That sounds like a massive corruption to suck back government incentives at the cost to the tax payers if I've ever heard one.
Rayman_321 8 months ago
I would go for the 2.5 blade option
Điện Việt Nam
Điện Việt Nam 8 months ago
*Vietnam Association of Electrical Engineers is a RUvid channel specializing in sharing knowledge and experience about electricity, interested people can visit .......................*
JKerman511 8 months ago
Hundreds of thousands of dollars? For a wind turbine? Why? It seems simple enough, how expensive could the raw materials possibly be?
MrSummitville 22 days ago
Design and build one for less, then sell it and make a small fortune or in your case ... go broke.
Actual Trump
Actual Trump 8 months ago
Windmills have 3 wings because president Obama's Lucky number is 3 Everything else is an made-up story
kevin klei
kevin klei 8 months ago
The video of the exploding turbines had 3 blades ????
Harley Me
Harley Me 9 months ago
nah theyre just to stupid to use bigger vertical axis turbine's where most of those problems dont apply
Christoo Hunders
Christoo Hunders 9 months ago
Smart !
exorientelux 10 months ago
Why do they have three blades? Quite simple. The junkies of renewable energy hate birds and bats. With three blades you kann kill three times as many birds and bats as with just one. We already have millions of animals killed by these monsters. We are destroying nature because of climate hysteria.
Big Cheese
Big Cheese 10 months ago
We are running the 3-phase system hence the 3-blades, very simple. No need to over-complicate.
globalcoupledances 10 months ago
I searched for the words "clock" and "cork" in all comments. Nobody asked why blades spin clockwise. That violates corkscrews, traditional windmills, and I think also of propellers and screws of ships
globalcoupledances 22 days ago
@MrSummitville It was not a problem with windmills in Spain and Holland. They all turn counter clockwise. Most videos of propeller airplanes turn counter clockwise, only one I found turn clockwise.
MrSummitville 22 days ago
Does the rotor spin in the direction that tightens the nut on the shaft = clockwise ?
tripjet999 10 months ago
Then, there is not knowing how to properly pronounce, "centrifugal."
MrSummitville 6 months ago
It depends upon where you live on the Earth ...
Abang Kecil
Abang Kecil 10 months ago
Then. Lets see what happens if it has 10 Blades. The wind would be cold
Sven-Erik Jansson
Sven-Erik Jansson 10 months ago
It's fewer blades not less bladed.
Florian Walter
Florian Walter 10 months ago
Why not investigating zero-blade designs? They should be most cost-efficient.
David Hendriks
David Hendriks 11 months ago
Very awesome to see that the first scene of this video is at the Zaanse Schans in the Netherlands, an area where I grew up nearby. I biked past this view daily for nearly 6 years.
oiewey 11 months ago
And where is the new explanation? For the sake of the name "Real Engineering" you owe it since 1 year ago.......Don't blow it.
Alfred Brownell
Alfred Brownell 11 months ago
wouldn't more blades make it faster because of the increased thrust of the wind on the blades?! im so confused
MrSummitville 6 months ago
Typically, more blades can spin faster in slow winds. But slow wind has no power, so who cares? In high winds, fewer blades ( ie 3 ) will spin faster than many blades. And that is where the real power is created.
Saskia van Houtert
Saskia van Houtert 11 months ago
I like windmills, perhaps more rotational is possible with the upperfront, thanks for explanation
Bashi Awan
Bashi Awan Year ago
I might say that this is not the reason as u have mentioned, the reason is solidity factor and others, actually by increasing the more blades we will not simply get the power increase rather the design will become difficult as the factor of axial force coefficient, power coefficient and torque coefficient need a compromise design for getting the max. Power and so on..
Bashi Awan
Bashi Awan Year ago
I wish if I could write more but I have exam tomorrow so next time I.A
oscar garcia
oscar garcia Year ago
They actually release more C02 into environment in the rebar that is needed to build the concrete foundation. The amount of electricity they produce in the lifetime of the wind turbine is more than the amount of C02 coal or natural gas plants would release for the same amount of electricity . But 5 times more expensive which is passed on to your electric bill . Government Oversite do your job investigate these scam artist who find a way
Fred Schnepel
Fred Schnepel Year ago
Because that’s the limit that Liberals can count. Everything after that is free, what!
basant vimal sharma
Three blades is good four bad luck five birds shit and blades stop six scrap metal thieves will dismantle and take it away three frightens everyone.
avada Year ago
Well, I saw a different explanation. One blade would be most efficient, but to imbalanced. Two blades, though balance experience some sort of yaw vibration and such mechanical stress. Three blades are the next best efficiency wise so that's what they use three.
Yoshika Kehelpannala
Your explanations are not adequate. They sounds a little.
Speedy O
Speedy O Year ago
em wind turbines don't need and are not designed be next to houses so count that out
This technology causes cancer!
Dustin Sand
Dustin Sand 7 months ago
That's 5g.
sorry not you
sorry not you Year ago
Jason Jordan
Jason Jordan Year ago
what about smaller turbines for residential use? I live in central Kansas and I see the big ones up close but what design would work best around or on top of my farm house? I've always thought a different design would work better for closer to the ground wind generators. How does say a cylinder or cone shape compare if held in place with magnet bearings instead of traditional bearings? Use gravity to close openings if the speed becomes to great. I live where it's windy more days then not but I don't need a massive generator to power a 2 story farmhouse and a few out buildings.
MrSummitville 22 days ago
Do not put the Wind Turbine on top of your home. Put in on top of a Pole in the ground or on top of the barn
McIntosh McDrone
If you have ever wanted to know how fast one of these wind turbines actually stand I made this video and it gives you a very close up look at that ruvid.net/video/video-vuZotgCqrUU.html
Justin M
Justin M Year ago
i always figured it was the same reason milking stools only have 3 legs
Him Bike
Him Bike Year ago
They have 3 blades to Kill more bald Eagles
Le Typ
Le Typ Year ago
Sadly no numbers to back the "conclusions"! so *vid in a nutshell* - more than 3 blades: not cost effective - less than 3 blades: too noisy
Flavius Nita
Flavius Nita Year ago
because it is not allowed with decimal point!
Mike Everett
Mike Everett Year ago
Good video, but hard to comprehend with that jungle music in the background. Would have liked to hear the upclose noise of the blades but the drum beat drowned it out.
Dragomir Ronilac
Rotational speed stability omitted... Shitty explanation
manila goodmorning
was the video changed? i am a fan of this video. something was changed. i don't exactly know what...
Matt Denihan
Matt Denihan Year ago
Wow I’ve never seen a turbine explode like that
Tom Meyers
Tom Meyers Year ago
Why do illegal aliens have three blades?
Tony Idle
Tony Idle Year ago
Surprising then how many two-blade turbines are in use?
Brian newton
Brian newton Year ago
I didn't know that I wanted to know this information, until I saw the video pop up. Thanks for sharing.
Edward Haughney
Nice presentation. Right to the point.
brensasi Year ago
These damn things just on Vids give me Anxiety Man...they are so big they freak me out
nomercy0401 Year ago
Munich FX
Munich FX Year ago
Giants galore Sancho.
Kerry Galway
Kerry Galway Year ago
The only part you did not explain is the part where the cost of the manufacturing and the energy used to make are more than the turbine will produce in it's lifetime
RZU 147
RZU 147 Year ago
Ok? What are you talking about? What your saying makes no sense.
The V164 is owned and produced by MHI-Vestas not Vestas, which is a separate company from MHI-Vestas with a different product line
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