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Using PC fans as wind-powered turbines - viable idea? Answered

Hi there, I'm helping to set up the permaculture garden area of a festival this summer and was hoping to make use of some recycled PC cooling fans as mini wind turbines to power some LED lights and maybe a small battery. Would this be possible? Can you generate a small AC current by forcing a motor to spin? Since PC fan bearings are fairly easy to rotate, I thought these would be a good option. I realise we'd need a capacitor connected to convert the AC to DC current, but what value? Sorry, I'm still a bit clueless about all this!

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hai.. can i make use of this pc fan to charge my phone?

Most modern PC fans are electronically controlled inside, you need to remove the electronics and solder directly onto the coils which is a real pita.... I think you'd be better getting some stepper motors and just rectifying the outputs of those.

I'm trying to construct a system that uses brushless PC cooling fans to generate some onboard electricity for an HHO generator. I have the fans. I'm trying to figure out how to plumb it and wire it and it is complicated because I'm combining alot of principles and not much budget into the project. I'm going to use Peltier TEC's, as well, to utilize some engine waste heat converted to electricity to assist with the production of HHO. I have a Dodge Ram 1500 to play with, so it has a fair amount of free space under the hood and elsewhere.

I'm new to this, but i used a big pc cooler, the small ones didn't work well for me, but with the big one i could light a red led with wind! I don't know if it was only that cooler, but i don't need to put anything extra on it, just wire the led directly on the cooler. I think the wind speed was about 15/20 kmph, i don't know for sure. The led starts to light when the cooler starts to make noise.

i have instructable in pogress on the topic. possibly will be out in few days

Sounds like a good idea, I just thought and checked in google and got this link.

Probably we need to do some modification, we can pull out the SMPS fan, stick additional large blade(s) to that existing fan. Since fan is quite small, it cant move in small wind movement, since there is lot of resistance generated in the coil due to flux. So a simple solution is to attach it with a large custom made PVC blade, would do the trick.

Author/Founder: Traffic Squeezer
Also a green enthusiast:
http://trafficsqueezer.sourceforge.net/go_green.html
+Kiran

I puffed into a little PC fan and got 2 volts at the peak. My experience with the Savonius turbine I made for my design class says that you could get even more from an AC vent or the like. The only thing I'm not sure about is what kind of amperage you'd get out of it--I think it'd be kind of low. But Kiteman's suggestion for an array of them wired up right could be the way to go if you have a bunch.

Could you tell us more about the permaculture garden? A critiquer I had for my wind turbine project said he'd like to see something like it running all over in a community garden sort of thing--just, instead of growing green plants, you're growing power plants. Heh.

As for AC, if it is an AC fan (they're often DC), you'll need a rectifier to make it DC. Radio Shack or other retail suppliers have those. If you're feeling more adventurous, though, I would HIGHLY recommend making you own with Schottky diodes (they tend to look like beefer versions of regular diodes.) They have a much lower voltage drop, which is crucial for harvesting as much voltage as you can from the kind of little devices you have in mind.

With the capacitor, get a big one. You're really just looking for something to hold a bunch of charge between the low points of the AC cycle, so no worrying about specific sizes like you would if you were making a filter for certain frequencies.

In fact, I would suggest getting what's called a "supercapacitor". The one I have at home is a .22 f--that's pretty huge as caps go, but it's physically smaller than a Mentos. You can use them like little batteries. I went to a workshop where we made DIY "shakelight" flashlights, and the instructor gave us those to work with. They're fantastic and can not only smooth the current coming from the generator, but can also hold enough charge to run a white LEDS off of it for a good amount of time just on its own. Plus, they don't wear down after multiple rechargings like a NiCad or NiMH would--which might make them slightly more eco-friendly (no idea how they're manufactured, though).

Hi Mike,
Many thanks for the suggestions- your Pringle design looks like a suitable candidate. We'd started off hoping that a large portion of the garden area could be lit by a generated voltage, but have gradually downsized our plans into maybe filling a tree with LEDs for a pleasant evening light-show! The festival site's here if you're curious: http://www.shambalafestival.org/

The other make we wanted to do was a pedal-powered cine-8 projector, so that we can project Charlie Chaplin shorts and soft-core Swedish "educational" films onto the side of a shed after-dark. Will have to research car alternators methinks.....?

I agree with Kiteman. I think they would work, but you will need something to funnel the air in. the fan blades are just not large enough to drive the load in low winds. If you had a coffee can or something funneling a breeze through, it may be enough.

You would need a mighty powerful wind! The high RPM of the fans at 12v means that it would need a similar RPM to generate as much.

True, but if he is looking to power a small battery, I as assuming 1.5 to 5v, and some LED's, then lower spindle speeds may work. Personally, I would just use small DC motors from toys and such with home made propellers geared up or something. PC fans are pretty easy to get though... hmmm....

Oh, picky, picky. The Apple IIc upstairs has a 3 1/2" and a 5 1/4" drive, and the Apple IIGS down here has both. Apple II, Macintosh, whatever. You got me. Hey, I'm only 14. I have the Mac stuff because my dad was the head Macintosh repairman for our local school district back when they were new, and he met my mom when she was in charge of computers at one school..or something like that. So I owe my existence to Apple computers. Thank you, Apple! *keeps typing on the stupid PC*

5.25" floppy drives were available as an option, but never included with any Mac (All Macintosh computers have always been abreviated, Mac). The only real purpose of attaching a 5.25" floppy drives was to access older Apple II floppies. The Macintosh LC & LCII had an optional attachment card that would run as an Apple IIc within the Mac. That card had the entire Apple II in one chip! Unfortunately, Apple never released the pinout to the chip. I'd love to build a miniature, fully functional Apple II!

Yeah, yeah. yeah. There was an Apple 5 1/4" floppy drive, though, so there! I win! Until someone else finds a needle to pierce my voodoo doll of self-pity... :-)

As far as I know, PC fans are actually DC. Have you ever blown at one to make it spin, though? Takes a lot of puff.

If you're wanting to use them "as is", you'll need a lot, maybe in a big panel, wired together (series or parallel? Not sure), with a shroud to accelerate the wind passing into the fans. The shroud is a funnel that "gathers" extra wind and pushes it through the turbine.

For ideas, see:
http://environment.newscientist.com/article/dn1292
http://www.ifb.uni-stuttgart.de/~doerner/vortex.jpg

It wouldn't be too hard to take them apart and remove the motor..or at least make the blades not go with the gears. Spray some wd-40, and you're good to go!

Seem that it might be possible. However, some PC fans are actually stepper motors, I think. Not many, but some. I have an article from eons ago, back in the '80s, about using the stepper motor from a Macintosh (yes, Macintosh, not Mac) 5 1/4" floppy drive and a PC fan-type fan blade...forgot where it was stolen from...and wired it up with LEDs so that as the stepper motor sent out the pulsed signal, the LEDs blinked rapidly and made cool POV designs that changed depending on wind speed. If you get this to work, make an Instructable!

CameronSS, With a logo like yours, surely you know that Macintosh computers never had 5 1/4" floppies! The pioneered the 3.xx" drives, that make that satisfying winding and grinding sound.