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someone else is selling one just like mine on ebay.

item #120836527301

i took the metal fly wheel off mine.
can someone tell me how i could hook up a regulator to this one?
 
i have a tread mill motor that ill sell.its dc and puts out good power at a fairly low rpm with a drill.puts out more power than my automotive meter will read at higher rpms.it would need a regulator.
It's my understanding that when hooked directly (thru a diode) to a battery that the battery will "clamp" the voltage at it's charging level, in other words a regulator shouldn't be required. But as with any/all wind turbines a method must be used to "dump" excessive current when ever the battery is fully charged. Check out the otherpower site and search "dump load".

Remember that it's important to match the blade size/pitch to your alternator/generator.

Note that (when talking wind power) a alternator generates a AC voltage and a generator generates a DC voltage

The bigger/better home made turbines normally use 3phase alternators (rectified and hooked to a battery bank) and then they use a INVERTER to change the DC battery voltage to 120vac.
 
someone else is selling one just like mine on ebay.

item #120836527301

i took the metal fly wheel off mine.
can someone tell me how i could hook up a regulator to this one?
As I already mentioned, you shouldn't need a regulator.
But you will need a diode between it and your battery to prevent the battery from back feeding into your motor.
 
Discussion starter · #24 ·
This question pops up here fairly often, and the bottom line is NO. Auto alternators have a number of problems that make them poor choices for Wind Turbines. They need to spin FAST, They require power to operate, They aren't sealed for the weather elements and they are simply very inefficient.

As already posted many people have used treadmill motors. Also used are most any DC motor (permanent magnet) or AC/DC servo motors.

There's a LOT more to wind turbines than mounting a set of blades to a alternator.

I suggest that you check out the Otherpower site. There you'll find all kinds of threads and help. People who have done it all and are more than willing to give advise.




http://www.fieldlines.com/board/

Thanks very much for this.
 
look into VAWT. something like this. ideas all over the net.
http://youtu.be/8MQaT9EbMDQ
VAWT's Vertical Axis Wind Turbines have been around for a long long time and have an advantage in that they don't need to turn (follow) into the wind.

But the number of disadvantages are numerous. They deliver fairly high speed but at very low torque. Their effective wind/surface area is only 1/2 of the actual area because there is 1/2 that is moving with the wind, but the other 1/2 is moving (fighting) into the wind. Their area is A=WxH a 6 foot high by 3 foot wide has an area of 6x3=18sqft. But only 1/2 is following the wind.. So 18/2=9sqft. That's a total of 9sqft exposed to the wind (not accounting for that other 9 foot that is fighting the same wind that is spinning it)

a HAWT Horizontal Axis Wind Turbine The area of a circle is A=PI x Rsq.
A six foot blade (six foot radius) has an area of 3.14x6x6=113.04sqft.
and all of that 113.04sqft is exposed to the wind.

If you had a HAWT that is 45 feet tall and 5 feet wide 45x5=225sqft and half that 225/2=112.5sqft (just picture how big that would be!).

You can see just how big of a HAWT you would need to equal the same swept area of a VAWT

Capturing/converting Wind power into electrical power is ALL ABOUT swept area. AND HEIGHT and of course WIND.

HAWTs DO work, but with current technology they have a long long way to go to reach the "current" level of VAWTs.


I'd like to mention that I am in a LOUSY location for a VAWT, I'd need a 200 foot tower to get it to clear surrounding obstructions (I'm in a valley) so I really REALLY wish HAWTs worked!
 
What about an old bike?

Here in the interior of Alaska we don't get alot of wind in the winter, at least not where I live. After reading all the post about alternators, old car generators and treadmill motors I got to thinking, what if you hooked up a treadmill motor to a 21 spead bike. Would take some modification but you could keep the kids in good shape and possibly generate some electricity. I'm not an engineer, so if anybody has suggestions I'm up for it. Happy peddling!
 
In that scenario, you are converting food engery into kinetic energy and then that into electrical energy and losing effeciency at each step. Only worth doing if you have an emergency where you need electricity- eg to use a radio to call in a rescue.

Each step loses a hell of a lot of the original energy - better off using the original source as fuel to drive a motor that drives a generator. It is however, a lot easier to put a dynamo on a bike and pedal than rig up a steam engine and fuel that with tinned beans.

If someone was using a stationary exercise bike anyway, and you had the batteries to store the electricity and what ever V kit to run or an inverter to convert it, then it would be a goer. Setting up just to use this kind of power is not economical.

When you consider your time into the bargain aswell, then you could earn a lot more money than what you would save on elecrtricity. Effiency must look at every avenue - could you generate the same amount in cost of electricty peddeling a bike for one hour as you could earn that amount of money working for half of minimum wage for one hour? No.
 
Electric generation

Check axial flux generator, there is alot of info on the Internet for building these at home. Also there are several ideas on many different designs for your windmill.
 
A car alternator or generator starts producing power around 500rpm and full power around 1000-1500rpm, thats why your voltage can sometimes drop when you start at a light with the lights and wipers and defroster and such all on at the same time.
You can rewind an alternator or generator to produce power at a lower speed but need a lot of time and wire.
Treadmill motors seem to be the best bet, high voltage dc when spun at a low speed will put out a low voltage dc.
You do need some sort of voltage regulator and you need some way to prevent over spinning the motor should you get a high wind (storm).
Search for variations of the 555 timer based charge controller, its a simple home built charge regulator and many will just shunt the extra power to a large load resistor which will work as a brake in high winds.
example" http://hackaday.com/2011/02/24/555-timer-based-charge-controller/

I've responded to several craigslist ads for free treadmills now, made the mistake of telling them what I was doing so one free treadmill ad disappeared and a $50 wind generator appeared that was from the same location :)
 
Here in the interior of Alaska we don't get alot of wind in the winter, at least not where I live. After reading all the post about alternators, old car generators and treadmill motors I got to thinking, what if you hooked up a treadmill motor to a 21 spead bike. Would take some modification but you could keep the kids in good shape and possibly generate some electricity. I'm not an engineer, so if anybody has suggestions I'm up for it. Happy peddling!
That's been done a number of times. You'll be surprised at how little electrical power a person can produce.


Again, check out http://www.fieldlines.com/board/

Here's one story.. http://fieldlines.com/board/index.php?PHPSESSID=2a76d9d43177f1d580a7a7d2bc3a4bce&topic=145055.0

and another (more current date wise) http://fieldlines.com/board/index.php?PHPSESSID=2a76d9d43177f1d580a7a7d2bc3a4bce&topic=145702.0
 
A car alternator or generator starts producing power around 500rpm and full power around 1000-1500rpm, thats why your voltage can sometimes drop when you start at a light with the lights and wipers and defroster and such all on at the same time.
You can rewind an alternator or generator to produce power at a lower speed but need a lot of time and wire.
Treadmill motors seem to be the best bet, high voltage dc when spun at a low speed will put out a low voltage dc.
You do need some sort of voltage regulator and you need some way to prevent over spinning the motor should you get a high wind (storm).
Search for variations of the 555 timer based charge controller, its a simple home built charge regulator and many will just shunt the extra power to a large load resistor which will work as a brake in high winds.
example" http://hackaday.com/2011/02/24/555-timer-based-charge-controller/

I've responded to several craigslist ads for free treadmills now, made the mistake of telling them what I was doing so one free treadmill ad disappeared and a $50 wind generator appeared that was from the same location :)

I'm not sure but I think you're talking about the RPM of the car engine and not the actual speed at which the alternator is spinning. The speed of the alternator is a function (besides engine speed) of the ratio of the drive/driven pulleys.
 
I'm not sure but I think you're talking about the RPM of the car engine and not the actual speed at which the alternator is spinning. The speed of the alternator is a function (besides engine speed) of the ratio of the drive/driven pulleys.
Yes, I should have specified that. Although if you take the pulleys into account the crankshaft pulley is usually larger than the alternator pulley so its spinning even faster, usually a 2:1 ratio so your alternator is spinning 1000rpm at a 500rpm engine idle and its not even putting out full power then.
 
Yes, I should have specified that. Although if you take the pulleys into account the crankshaft pulley is usually larger than the alternator pulley so its spinning even faster, usually a 2:1 ratio so your alternator is spinning 1000rpm at a 500rpm engine idle and its not even putting out full power then.
And that is my point, a cars alternator needs to spin FAST in order to generate power. And don't forget that while it's putting out power it's USING a good portion of that power to generate the magnetic field it needs in order for it to operate. In a car where there's lots of available horse power, using several of them (horse power) is a NON issue. Remember that a ONE horse power is "about" equal to 746 watts. So if that alternator is "eating up" 3 horse power that's 2238 Watts or 2.238KW. That's more power than most large home built wind turbines put out.
 
I've made several attempts to make an alternator into a wind turbine. I have had turbines, hooked to a battery to energize it spinning so fast that the blades of the turbine self destructed, and could not get it to charge. A car engine idles at 600-700 RPM. the crank pulley is 3-4 times bigger than the alternator pulley. I am a mechanic by trade, and I have to bring an engine up to 1000-1500 RPM to get a good test reading. Without modification, I don't see it ever working. The problem with gearing it up is that it takes more force to rotate the turbine as you increase the gear ratio. You can gear it for a 100:1 ratio, but you would need a huricane to make it spin. I have a 6 hp briggs and stratton engine on a 120 amp alternator, I have a 5 inch pulley driving a 3 inch pulley, and if I really load it, it will stall it.
 
And that is my point, a cars alternator needs to spin FAST in order to generate power. And don't forget that while it's putting out power it's USING a good portion of that power to generate the magnetic field it needs in order for it to operate. In a car where there's lots of available horse power, using several of them (horse power) is a NON issue. Remember that a ONE horse power is "about" equal to 746 watts. So if that alternator is "eating up" 3 horse power that's 2238 Watts or 2.238KW. That's more power than most large home built wind turbines put out.
Thats what I was saying too, you can't spin your blades fast enough to produce any power with a car alternator or generator.
 
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