We built a 1000 watt wind turbine to help charge the battery bank that powers our offgrid home. It's a permanent magnet alternator, generating 3 phase ac, rectified to dc, and fed to a charge controller. The magnets spin with the wind, the coils are fixed, so no brushes or slip rings necessary.

Update: DIY Amp Hour meter for monitoring charge!

All about homebrew wind and offgrid power systems, the complete reference!

Step 1: Build the magnet disks

We had 12" steel disks hydro cut. We cut a template for mounting the magnets. Then we mounted 12 grade n50 magnets around the outside edge. We then built a form, and poured the resin with hardner.

Step 2: Build the coil disk

We wound the nine individual coils, soldered them in a 3 phase wye configuration, and encased them in resin. We used 35 turns of 2 parallel strands of 14 gauge enameled (magnet) wire for 12 volts. Use 70 turns of single strand for 24 volts. # 3 phase diagram shown here shows 3 stator coils. each of those coils is actually 3 coils in series. coils 1,4, and 7 are series together, 2,5, and 8 are series together, and 3,6, and 9 are series together.

more details, see the following page 15 for the series star, 1-y diagram.



Step 3: Build the bearing assembly

Two Harley Davidson wheel bearings are inserted into the pipe, with a smaller pipe locked between them to keep them in place.

Step 4: construct the blades

The blades are 2" x 6" pine, cut at 10 degrees on a table saw, and sanded into a rough airfoil. Not perfect, but close enough.

More can be found at




Step 5: Further Reading

<p>How much would this cost to make? I'm thinking of doing this for my senior project.</p>
$1500 or there abouts.
<p>hi sir please replay all of my 4 question because I am doing this as my college project.</p><p> 1. This my rough diagram arrangement of mag rotor,it is correct or any changes take place.(below)</p><p>2.i want to wind 14# 3parallel wires 35 turns to produce 1500w and how many rpms should rotate to get 1.5kv, can u estimate how many amps can I get.</p><p>3.and it can rotate 24hours, are any damage occurs.</p><p>4.i am buying 12v luminous inverter with 1000w*2batter ,how much time will take full the charging.</p><p>Please reply all of my 4questions because I am doing this as my college project. </p><p> Thanks,.</p>
<p>thank q ,</p><p> which type of inverter and battery i should use for storing 1500watts</p>
1500 watts is a instantaneous amount of power. Batteries store amp hours or watt hours. Neither has anything to do with an inverter. clarify your question.
<p>Depends on your daily loads, and how much wind you get daily. Aren't they teaching you this in college? It's basic high school physics.</p>
<p>hi sir ,</p><p> i forgot to say we are implementing only your turbine planes,and we are not doing wind turbine (only we are doing magnet coil rotor),</p><p> please answer IF I GET 1500W AND 125AMPS FOR 1HOUR WHICH TYPE OF INVERTER AND BATTERY I SHOULD USE.</p>
<p>You have not specified your loads. What wattage are they, how many hours do they run, how much run time do you need when the alternator isn't running . This is what determines battery and inverter, not the alternator.</p>
1. correct<br>2. 650 rpm, 1500w / 12v = 125 amps, if you have 12' blades at 15mph, or 4' blades at 30 mph.<br>3. 24 hour operation only affects bearing life.<br>4. battery charge time is dependent on how low the batteries get (amp hours out), and the amount of charging available, (amp hours in). With wind, there's no way to forecast your daily ah production, as wind is too variable.
<p>Thank you</p><p>if the generator is kept constant producing about 800 watts, using an inverter, without using the battery,</p><p>I wonder if you could provide 800 watts to the load used</p><p>without battery</p>
Theoretically, but in practice, loads are rarely constant, and neither is generation.<br>
<p>very friendly and helpful</p><p>Axial Flux buy documents Alternator and Wind Turbine Plans</p><p>that good information and books provided in the same package, very affordable, so you can get valuable and interesting information and practice</p><p>any doubt what consultare</p><p>see you soon</p>
<p>Hello one question</p><p>the coils do not carry any core, the air is nucle</p>
This is an air core design. Reduces cogging.
<p>Is there any way i can see some more photos of the fan? </p>
At <a href="http://green-trust.org/products/" rel="nofollow">http://green-trust.org/products/</a> look for the axial flux wind turbine plans. there's a whole section on blade construction.
<p>can i use any glues</p>
In what context? holding the magnets? heat usually softens glue.
<p>hi sir,</p><p>i am winding a coil with 2 parallel wire of 14 guage. when i am winding the coils they are tight,after removing coil they are getting lose can you suggest any ideas.</p>
<p>Tape them with electrical tape.</p>
<p>thankq </p><p> ok i want to use 14 guage, 2 parallel wires ,35 turns.how much diameter present inside the coil. </p>
you want the magnet to pass one side, then the other, not the ends, so the whole needs to be longer than the magnet.
<p>hi sir,</p><p>can u say coil inside and out side diameter,and i am using 12v winding which guage is best for less wastage of volts. </p><p> thanking u.</p>
coil diameter will depend on wire gauge, and your ability to wind tight coils.
wire gauge has no bearing on volts. The thicker the wire, the more amps you can draw without overheating.
<p>hir sir ,</p><p> how to calculate number of turns required,i want 2kw turbine how many turns i should turn(12v )and 2&quot;*1&quot;*1/2&quot; magnets enough ....?</p>
<p>thanks for u r replay sir'</p><p> 2&quot;*1&quot;*1/2&quot; magnets is enough for producing 2000w turbine</p>
if they are strong enough. N50 should do it.
the number of turns specifies the voltage, the gauge of the wire specifies the amps, and the length of the blades determines whether you can capture enough wind to turn it at that load. You might need 35 turns of 4 parallel strands of 12 gauge wire. You would need around 22mph winds with 8' blades.
<p>hi sir,</p><p> can u suggest diff b/w 24v and 48v. if i wind my turbine for 48v which guage wire should i use and how many turns i should turn , at which rpm i can get 1000w.</p>
to double the voltage, you double the number of turns, and you can use a size 2-3 smaller wire (14 instead of 12awg). You still have to spin at 650 rpm.
<p>can i make it in 1phase by using 12 coils and ,24 magnets,how much amps can i produce in 500 rpm,and how many turns of wire i should turn for 48v and wire guage also explain.</p>
<p>It's not a single phase machine. You are on your own with major design changes.</p>
<p>please advise</p><p>how many RPMs it should turn to produce 1000 W .and at 1000 w how many amp will be produced</p>
650 rpm (30 mph wind), and the ampsdepend on the voltage you wind for 1000w / 24v = 41 amps
<p>I want to make 48v ,1000w, which guage wire i want to use and how many rpm it should turn </p>
<p>PLEASE ADVISE</p><p>I've read almost all the replys (there are so many) but I noticed that no one has considered using alternative materials to mount the magnets onto, are you aware of any issues regarding having them mounted onto steel plates and the potential losses that this may create, also what if they were mounted in slots so that the faces in say a stacked 3 (magnetic) plate system, (the middle plate being mounted in slots and having 2 sets of coil resin discs in between them thus making it a total of 5 layers) so that both sides of the center plate provide the magnetic field thus providing potentially a more efficient system? </p>
<p>I was wondering this too</p>
<p>The magnets need to be mounted on a steel plate to complete the lines of flux.</p>
<p>Thank you <a href="http://www.instructables.com/member/sspence" rel="nofollow">sspence</a> for reminding us, I've taken on board exactly what you have stated, but just on an academic level surely the magnetic lines of flux travel through air space anyway and arrange themselves accordingly , I remember as a child that putting a metal bar across the end of a horseshoe magnet which if memory serves effectively shorts the magnetic field. as I say this is just an academic aspect and hopefully a discussion</p>
The steel plate does not incur losses, it's what completes the magnetic flux, and make this work. having a spinning magnet plate in between two coil plates would require a lot more machining, but it's possible. We went for what's possible in a back yard DIY approach.
<p>I will be talking to a man I know that manufactures magnets, about the potential losses or gains in using different mounting materials and possible benefits of slot mounting etc, they don't let him out much, he's on holiday taking in the sites of several magnet conventions, He's all about magnets, they are his passion ! </p><p>I may have also sourced an affordable priced supplier for these Type N50 at 50mm x 25mm x 10mm, I've not placed any orders as yet. Watch this space.</p>
<p>The magnets need to be mounted on a steel plate to complete the lines of flux.</p>
<p>Thank you for such a prompt response, I am looking to create such a setup as we have discussed, I intend to simply stack these with the magnets mounted in slots, while I'm at it I will be using other metals and will report on / see what occurs, I may use other prime movers as opposed to simply wind power as you have mentioned in a previous posting, this is of course when I can obtain an affordable source of the Neodymium magnets specified, I'm looking at metric 50mm x 25mm x 10mm, these being respectively smaller by the following sizes of 2mm x 0.4mm x 2.5mm-ish smaller than your 2 &quot;x 1&quot;x 1/2&quot;. I do not expect this will create any issues.,I do like this scalable setup and again thank you for bringing it to our attention.</p>
<p>qual o tamanho dos discos( di&acirc;metro interno e externo)?? e qual di&acirc;metro interno das bobinas? grato!</p>
disk is 12&quot;, magnets are 2&quot; x 1&quot; x 1/2&quot;, and coils are just a bit bigger than the magnets, so that the complete magnet passes through the sides of the coil, not the ends.
<p>Are the magnet poles orientated in the opposite direction, relative to the center, on the opposing magnetic rotors? So it goes north to south through the stator coils? Awesome project, i'm making a much smaller one as a trial. I was also wondering, do you know if energy companies would let you use home made turbine on the grid? I want to make one for my house but it's on the grid, and the weather is variable at best in the UK.</p>
<p>I would also like to know which direction the magnets are oriented!!!</p>

About This Instructable




Bio: Professionally, I'm an IT Engineer (Executive Level) and Electronics Tech. I'm a Amateur Radio Operator (KK4HFJ). I lived off grid, with Solar (PV ... More »
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