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Homemade Wind Generator

By RD Copeland

Tags: off the grid, wind power, generators, home energy, wind turbine, Texas, RD Copeland,

 DIY Wind Generator

Are you headed for the beach or going camping in the mountains? Maybe you live on a boat, visit a remote cabin or you're living off-grid. Electricity is yours for the taking as long as the wind is blowing... And you can get it on the CHEAP with an easy homemade wind generator. Light up that storeroom, barn or use the generator to keep all your vehicle batteries charged too.

My off-grid cabin's electricity comes from solar and wind power, stored in 6-Volt golf cart batteries. A charge controller and battery minder keeps my system from under-and over charging. The whole shebang cost me less than $1000 and I have lights, fans, TV and stereo, refrigeration, and a disco ball that goes up for special occasions.

If you can turn a wrench and operate an electric drill, you can build this simple generator in two days: one day of chasing down parts and one day assembling the components. The FOUR basic components include a GM pickup truck alternator ($40 new), a GM fan-clutch assembly ($35 used), the bracket for mounting the generator on a tower or pole ($25 galvanized pipe and fittings version), and a tower or pole ($20 for 15 feet of 2" tubing, used). If you're a Ford guy or a MOPAR gal that's fine, just make sure the alternator has a built-in voltage regulator. You'll also need some electric cable or wires to hook it up to your storage battery. I used 8 gauge, three-strand copper wire pilfered from the oil patch. (And they said the transition from fossil fuels to renewables would take years. Pfft!)

My Wind Generator Parts List

Car/Truck Alternator - GM 1988, 350 motor, alternator with built-in regulator (used in illustration). Almost any alternator with a regulator will work but use a new one. It should have a warranty. 

GM Alternator

Car/Truck Fan Clutch Assembly - GM 1988, 350 motor -used

 GM Fan Clutch Assembly

Bracket Assembly for Mounting Alternator/Fan

If you have a welder, making a bracket is simple. I used 1" square tubing for all the bracket pieces and a 2-feet long piece of 1" pipe for the Rotating Stem that fits inside the pole. If you don't have a welder, fear not. The Bracket Assembly can be fitted up with 1/2" galvanized pipe and fittings. Here's a list of the pipe fittings you'll need:

1/2" Tee (5X)
1/2" Elbow (2X)
1/2" X 12" Nipple (2X)
1/2" X 6" Nipple (2X)
1/2" X 1-1/2" Nipple (2X)
1/2" X 2" Nipple (2X)
1/2" X Close (2X)
Galvanized Pipe Bracket

A tail fan to spin the generator around lining it up with the wind's direction must be attached to the 12" nipple at the back of the bracket. Cut a fan out of old tin siding or roofing with tin snips or a cutting torch. A right angle triangle shape works best. Drill three holes in the nipple. Use self-tapping screws (steel roofing screws work good) to affix the tail to the nipple.
(See photo)

Tower/Pole - I used an old Television antenna tower 20' tall with a 2-1/2" diameter pipe top piece. You'll also need a Stop at the top of the tower which lines up with the Stop on your bracket assembly. This can be welded or bolted onto the tower. The Stops will only allow the generator to turn 360° clockwise and counterclockwise so your cable doesn't get twisted around and around the pole/tower.

A joint of 2-3/8" oil field tubing anywhere from 10' to 20' in length (height) attached to a building or bolted to your truck bumper makes a good tower. Make sure it is secure and you may need to use guy wires. If you aren't sure how to mount the generator, send me a message and I'll try to help.

Fan Clutch to Alternator Attachment:

The fan clutch hub can be welded directly to the alternator hub, just make certain the fan is perfectly straight in line with the alternator shaft. Make sure the alternator's built-in wire plug ins are located on what will be the bottom of the generator. If you don't have access to a welder, create a union from the 3" washer and four bolts, which will fasten the two major components together. Drill four holes to match the holes in the fan clutch. Use a 1/4" tap to cut threads in the holes. Unscrew the alternator pulley nut, remove the pulley and small fan. Slide the union over the alternator shaft---bolts pointing away from alternator, then reattach the alternator fan and nut onto the shaft (leave pulley off). The large nut will hold the union in place. Attach the fan clutch assembly to the bolts now protruding from the alternator. Tighten nuts with lock washers in place.
You'll need:

3" washer, 3/16" thick, 5/8" hole.
Electric drill
1/4" steel drill bit
1/4" thread tap
1/4" X 1-1/2" to 2-1/2" bolts (4) and lock washers (4)
(To determine length of bolts, stack the fan on top of the alternator with both shafts in line, fan pulley on alternator pulley. Measure length along the two shafts from back of alternator fan to back fan clutch hub. Use this length for the bolts.)

Tower of Power

Once you have all the generator components fastened together, mount it on your pole or tower. Insert the pipe on the generator inside the larger pole pipe (or the top of your tower). Use two steel washers together to create a bearing between the generator and tower for a smooth surface for the generator to pivot 360 degrees. Attach the positive and negative wires to the alternator and secure with zip ties, baling wire and/or duct tape on the bracket and along the tower. It isn't really homemade unless it has a little baling wire and duct tape on it somewhere, now is it?! You'll need assistance standing the tower and generator upright as it will be pretty heavy. Ropes and a come-along will help if you're going up fairly high. If it's always windy in your location, you only need to be high enough off the ground to keep the moving parts safely overhead. Securely fasten your tower in place. The wind can be deceptively strong so do not cut corners on this final assembly stage.

Now that you've erected the wind generator connect the wires to your battery(ies) with a charge controller in between to prevent over-under charging. Now you're ready to hit the lights, crank up the jams and bust out those old disco moves I know you've been saving up for an electric slide on the beach with your family and friends.

Build and use at your own risk. My generator works fine but you are responsible for your work. Good Luck and Power Up!

6/5/2016 10:21:14 AM

OK, This system could work....if you had 50 MPH winds... An alternator,(automotive), requires a minimum of 700 rpm to activate the field coil for electrical production, Running the blade directly off of the shaft is extremely unlikely to achieve this speed under less than hurricane conditions. This problem can be overcome by inserting permanent magnets in the spaces left open on the armature. Doing this will allow the alternator to produce electricity without having to activate the coils.

2/28/2016 9:59:19 PM

What is so incredible about it? in the first place the fan is wrong way around, there are no wires connected to it, it look like a redneck rig that did not work so they gave up. It can work with some modifications and some electronic circuitry to cut the field current when there is no wind, or the rotor have to be fitted with permanent magnets in the place of the rotor coil. Some more improvements will be to change the stater coils from star to delta.

2/13/2016 8:51:02 PM

What type minder and regulator are used?

1/25/2016 4:02:24 PM

I assume that one also needs an inverter for use that is connected between the battery bank (how many and what size - 12 volt, deep cycle?) and an inverter (how many watts for the GM 350 alternator?).

9/7/2015 7:58:23 AM

This is so wrong on many levels. Too many blades, will turn too slow. Inefficient alternator (power robbing field coils) designed to run at fast rpm's That this turbine can't achieve). This is a lawn ornament, not a power plant.

7/15/2015 8:18:30 PM

OOOhhh Great idea!!!!

6/4/2015 4:03:27 AM

That is Very good innovation in Generators filed, till now we heard about diesel generator, electrical generator, solar generators. Wind Generator is showing creating mind of man power. Wind generator is cheap in prices and easily established where wind is blowing. Like you online battery store gives generator batteries on cheapest price and genuine products.

4/26/2015 11:15:26 PM

older alternators produce 110 volts if you remove the voltage regulator.

4/26/2015 9:58:23 PM

Very good article. This is the type of project I like because the use stuff that's easy to find or that I already have. One minor comment on the fan clutch to alternator attachment. If you are going to tap the holes for 1/4" bolts, you need to drill them with the correct tap drill size. Buy the tap first. It should have the tap drill size indicated on it. Now I just have to start scounging parts.

4/25/2015 4:51:38 PM

The wind generator is a great idea and the article is well written and provides clear directions to anyone wanting to build one. Iwould add one small observation, however. The picture showing the completed unit shows the wind blade attached to the shaft with the convex surfaces of the blades facing forwards into the wind, as if it were an electric fan or an aircraft propeller blade, intended to PULL air into itself and blow it out the back past the motor. I would suggest, that if the blade were flipped over 180 degrees on the shaft so that the concave surfaces of the blades face the incoming wind flow, the air would be directed more efficiently in a radial direction off of the blades, thus providing more action-reaction thrust against the blades to turn the unit. This would be more efficient and would provide more mechanical HP to the shaft to turn the generator, and hence, more electrical power from the same amount of wind flow. But my compliments to the designer/author. This can make a great project.

4/24/2015 11:16:21 AM

any chance of some pictures of the copper pipe /plastic pipe set up ... so you don't wrap up the power cable? A pic or two is worth a thousand words! Love this mag! This is a very usefully project ... I would like one for the roof of my motorhome. ( set up once I arrive at the camp site) Thx for your time!!
4/24/2015 10:05:48 AM

How much energy does this generate?

4/7/2015 10:29:50 PM

hello i was wondering how to i hook up the wire from the alternator to other power cables

3/26/2015 3:54:30 PM

I have an old gas generator I plan to try as another wind generator when I finish up planting this season. All I can say is try it. You might attach the fan to the generator, mount it on a short pole or even a sturdy post, catch some good winds, then test it with a multimeter before you mount it for good. I have four, 6-volt golf cart batteries wired for 12-volt system, hooked up to the wind generator and two solar panels which produces electricity for my cabin and a water well. Thanks.

3/25/2015 3:20:50 PM

Could an old gas generator be used for the inverter in it? If so, id like to see how this could be wired in, along with the batteries. Would use this for my camper, eliminating the need for propane.

3/2/2015 10:13:21 PM

How mean battery's do you need for the wind mill ?

11/16/2014 4:54:43 AM

Gen good, stops bad. Pass power down thru larger rotating bushing with 'commutator' made of 3/8" & ½" copper pipe with plastic tubing between the two pipes and over the outer pipe for insulation. At bottom, outer pipe 1" shorter than inner. Solder gen wires to pipes, pot pipe assembly centered in bushing w/epoxy. Below on tower, pick power off rotating pipes with copper strip brushes (4 per pipe, 1 ea. side, 8 total) held in wood frame. Could also use replacement generator brushes. Now windmill can rotate freely w/out cable wrap and won't get stuck against stop.

7/30/2014 8:06:59 PM

This is exactly the type of set up I've been looking for. I've seen other designs on the web and although inexpensive the parts are hard to come by. This post shows very easy to find materials and gives great instruction. More like this please. lol!

7/17/2014 9:07:56 PM

I thoroughly enjoyed the article! Keep em coming, you are doing an amazing job educating the internet!

7/10/2014 7:57:17 AM

And to think, some companies charge thousands for those things! Small investment, free energy - what's not to love? (Unless, of course, you think you'll miss the adrenaline spike one gets when opening their electric bill each month!) Great article - think I'll give it a try.