Understanding Wind Power (Wind Generators / turbines)
- Filed under: Solar Power and Off-Grid Living, Uncategorized
- Date: Aug 14,2008
What seems like a long time ago, I decided to learn how to create my own power from scratch. Partially because my little sister lives in an off-grid home, but mostly because it’s just plain cool ! It took a few months of intensive studying, but I figured out Solar Power pretty fast. At the same time that I started learning how to generate power from the sun, I was learning how to generate power from the wind. It took me until now to finally understand JUST THE BASICS of this subject enough that I feel confident writing about it and starting to work on my own set of wind turbines. This article is about the very BASICS of wind power, as I understand it.
How does a wind turbine work ?
Wind turbines operate on a simple principle. The energy in the wind turns two or three propeller-like blades around a rotor. The rotor is connected to the main shaft, which spins a generator to create electricity. Generators (or alternators) are made of really strong magnets that are spun around very quickly next 
to coils of magnet wire. The effect of the magnets whizzing by each coil produces an electrical current in the coil. You connect the coils together in a certain fashion and then it’s like solar power : you go to a charge controller, which is connected to batteries, then an inverter, then regular house wiring. (Although if you’re turbine is producing AC electricity, which most are, you need a bridge rectifier to convert it back to DC before going to the charge controller.
That was a great example of how a wind turbine works. Imagine this happening, but at MUCH higher speeds thank to the wind pushing a series of magnets over a series of coils. A single spin of the wind turbine would equal what he’s doing during the entire video.
How much power can I expect from a wind turbine ?
This depends entirely on the specifics of that turbine. They can range from tiny little generators that cou
ld pretty much only charge your cell phone, to gigantic turbines that could power a small town. From what i’ve read, you get the most bang for your buck if you learn to make your own wind turbine. This is what i’ve been trying to do for over a year now.
About building your own wind turbine :
As far as i’m concerened, the hardest part of all this is the generator or alternator that actually makes the power. Although i’m finally starting to understand how to build your own alternator from scratch using coils of magnet wire and rare earth magnets, it’s not the only way to do it. (It is the best way though)
An easier way, would be to use permanent magnet motors. PM Motors are pretty much the same thing as an alternator. Usually, you send electricity INTO the motor and it’ll make the motor spin. However, if you reverse the process and spin the motor by hand (or with a drill or by CONNECTING IT TO propellers and putting it up in the air!) it will actually GENERATE electricity where you would usually put power IN to make the motor spin. This is great because if you get your hand on a good PM motor you don’t need to build your own alternator / generator !
IF you had a PM motor, you basically just need to connect the spinning part of the motor to your propellers and you’ve more or less got a wind turbine built ! (Keep in mind, i’m talking only about the very basics here)
Helpful reading materiel about how to build a wind turbine :
Otherpower.Com is one of the best resources on the web as far as alternative energy goes. They have a great forum with very knowledgable people.
This instructable is pretty well documented and helped me understand the principles a lot. He built himself a 1000 Watt wind Turbine from scratch for a few hundred dollars! (The equivalent in solar panels would cost atleast $4000 and would take a lot more room)
This site has done lots of experiments with different sized coils and used hard drive magnets to make his generator. Although the results were not great, this site REALLY helped me a lot to understand how everything comes together.
More to come !
I will be writing much more about wind power, including the different kinds of wind turbines which we haven’t talked about at all in this article. If you’re interested in Solar Power please stick around and browse this site. There is lots of information on this subject. Feel free to email me or leave a comment here on techienation if you have any questions.
If you would like to learn how to build your own wind turbine, you NEED to get these detailed books explaining how to do it without spending a lot of money.
14 Responses for "Understanding Wind Power (Wind Generators / turbines)"
This is a great article! It is very informative and I learned how wind turbines work inside which I didn’t know before. I remember from my physics lessons at school (just about) that you could generate power from a motor. What kind of motors are PM motors? Could I rob the motor from inside one of my kids motorized scooters and hook that up to a propellor? Or do they need to be stepped in a certain way.
Simon
Wow that’s a great question Simon. I should have mentioned that in my article, but it’ll be part of a future one.
I’m still trying to figure out common ways to get a permanent magnet motor. I too have been eyeing that electric scooter I bought myself and wondering if the motor would work.
I know 2 ways of getting these permanent magnet motors. Ebay is easiest. They flat out say they’re permanent magnet motors and give the rated voltage. From what i’ve read and been told, AMETEK motors are the best for this.
The other option, is OLD TAPE DRIVE motors. Not a floppy disk, the good’ol fashion Tape backup drives. Those motors are apparently some of the better ones to use. Treadmill motors are also known to be good for this. Other than that, i’m still looking.
I have started asking all IT people I know to keep old tape drives aside for me, as well as old hard drives so that I can salvage the magnets. (The harddrives I have a feeling i’m gonna be gettings hundreds of them!)
… and yes they do need to be stepped in a certain way. Your basically looking for a PM motor that can supply the required voltage at the lowest possible RPM.
So my question is, can you build US a 1000 watt turbine from scratch for a few hundred dollars?
Hmmmmmmmmmmmmmm?
That’s the plan !!! Although to be honest, you’ll probably end up with a 300 Watt turbine before the 1000 watt one. I plan on building one the easy way first with the PM motor I was describing, and after starting to work on making my own alternator. That 300 Watts extra will make a big difference considering you only have 30 watts of solar panels !! (so 10 times more power!)
Thanks. it is goog. but it’s not a technical text.
hi there.
i have read all the above stuff. its interesting to know all. actually i came accros this site through google search and the idea in my mind was of creating a batery charger as a reverse action from the action of an ordinary home ceiling fan. as we know rotary movement of anything can produce electric current. so why not generate current while using the current. this will enable the UPS (s) to give a longer backup while there is power failure.
can u define anything that could work for such a fan generator to give DC volts to batery for recharging.
anything of such kind would be of great help to redirect the direction of my thinking.
waiting for ur answer.
Hey I was kinda curious. Wouldn’t it be more practical to make a wind turbine that has the standard blade system with the rare earth magnets, and another set of blades on the stator part with those blades reversed with some sort of brush system to collect the energy that is sent to the rectifier. Wouldn’t that in turn make it to where the stator and the rare earth magnets are both spinning, but opposite of each other produce more speed that is spinning between them and produce more power? In response to Ahad khan I have also seen some youtube vids on how to make one out of a fan as well you have to do some customizing with some rare earth magnets inside the case. You can find it on youtube. What you are looking for is a rectifier. it will convert AC current to DC current which you hook up to your batteries and a dump load like a heater or something. I’m not sure how much it will put out but I have 2 spare fans and I’ll find out. You can look up how to make a rectifier on google out of diodes. Haven’t gotten that far yet. Found out that wal-mart has some good earth magnets though for that use in their crafts section. They were all bought out when I went though lol. Would be interesting to hook a stator and magnets to a bicycle as well, that way when there is no wind you still have human power. Hell, linked with solar panels and a wind turbine, I would say you would have yourself a little grid of your own. Check out maglev wind turbines as well. those seem to be more wind sufficient quieter and more space conservant. I like the Idea of a frictionless turbine floating over a stator. Thx btw on the info for the big wind turbine. Very informative. I guess they have the gearbox to up the rpm of the shaft going to the generator.
So I was also reading on your solar panel section, would I also need the charge controller for the turbine and I was wondering does the rectifier keep the power from traveling back to the turbine or would I need another diode between the fan and the rectifier? wasn’t ever exactly certain.
Very good photo show for the components of wind turbine however the photo is for the small wind turbines. The nacelle is very large for the large wind turbines.
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i like this website but i coulden’t find a energy transfer diagram for a wind turbine!!!!
I m very happy to see this web site.this is very useful web site . i want to make a small model .can u give me some tips i m very much thankful to u.
benjamin
please can you help me i have made a stator with 12 coils and a rotor but how much of a gap do i need between them thanks
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