Speaker Wire vs. Enameled Wire

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I have a science project to build a hydro generator, I went to home depot to get wiring for the coils and he gave me some copper wire, the copper wire was twisted and stuff and it looked fine, so I bring it home then i realized the wire had to be enameled, and I doubt he gave me enameled wiring and by the looks of it it doesn't look enameled. (Then again it might be) So I was looking through my house and found some speaker wire, covered in plastic and it had 2 wires in it... If i strip both the pieces apart can those be used as wires to be coiled for the electricity generation?
Short answer no.
You need enamelled wire which you won't find at Home Depot.
Google it.
If you live in a large city, maybe you can find a guy who rewinds electric motors, he might sell you a little.
Or get an old but still good transformer (it won't do if burnt) and carefully disassemble it.
With the speaker wire, the fill factor of your coils will be very low, because the thick insulation takes up space that is not available for windings, leading to poor performance as a magnet or generator coil.

Better get some (enameled) magnet wire. Or sacrifice an old transformer and unwind it. It's quite easy after removing the laminations...

Yes, if you want to try, separate it then coil it.

Another question comes to mind: Do you have to build everything from scratch? A small DC motor with a permanent magnet stator (as used in many toys, car stuff like power windows, wiper etc) would work as a generator if your model power plant makes it mechanically turn.

Do you know how many current will flow by this conductor? Be sure that current density (Ampers div mm squeared of copper area) isn't less than 4 A/mm2. If this isn't the case, the wire will become overheated.

If he is trying to build a generator with thick insulated, coiled wire, the efficiency as well as the current density will be close to zero, so no problem with overheating :)
Or take an old (non toroidal) transformer, pull the laminations then use the laminations to build a suitable magnetic structure around the ready wound bobin, either a permanent magnet alternator or a full on externally excited machine should be possible, and it saves you a lot of coil winding.
Transformer laminations have good magnetic properties for this kind of thing anyway.

You could use speaker wire, but the machine will be massive and very inefficient as the insulation is very thick.

One interesting variant to play with is a homopolar machine, for the contacts graphite will do in a pinch, but when I built one in high school I found that a mercury wetted wiping contact had lower resistance, and let me make more spectacular fields. Granted the early experiments I did had mercury spraying everywhere due to mechanical resonances as the thing spun up, and I suspect that a kilo or so of copper disk at 90K RPM or so would cause paperwork in a school context these days (We just piled some sandbags around it in case of a bearing failure).

Both Mouser and Digikey will have a wide range of enameled wires available, and I bet the schools physics department can find you some if you ask (The local university physics department will almost certainally have some if your teacher asks nicely).

Regards, Dan.
This is solely a science project for class, my assigned project was to build a generator, she said that it must be able to give off power, I will plug it into a multimeter so she can see that power is being generated, as long as it will generate some sort of energy to the lightbulb then it is fine if i coil the speaker wire with the plastic coating it will still generate some electricity, the efficiency no matter how low will still be above 0 right?
Above zero yes, but I sincerely doubt that a reasonably sized coil of speaker wire will generate enough electricity for even a small torchlight bulb...

If you have to build everything from scratch, did you already make yourself familiar with the basic principles of electric power generation? Just winding a coil will not make a generator...

If you have the magnets, just go to your local Radio Shack or electronics parts store, tell them what you want to do and they will sell you some small gauge enamelled wire to build your generator. Then go online and google it, there are tons of sites from hobbyist's that show you exactly how to. I did this sort of thing with my GF's son all the time. It's cheap, fast, easy and it's a lot of fun if it's something you are actually interested in.

EDIT: It seems you have the design already, good. It's fun when you see that light bulb glow. :)
I'm fine with space being lost but would it work? I am barely powering a small lightbulb. As long as it works (Faint glow) It should be fine... So can I coil it?

Post your project.
Otherwise it's imposible to answer with precision.
By the way, lighting even "a small bulb" is quite some power.

This bicycle light generator does just that, and needs quite a few turns of wire, at high RPM to accomplish it:
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