# COMMUNITY : FORUMS : SQUARE PEGS

## Small generators.

Most everyone here knows (I assume) how the generators work in RC cars and there's an instructable that shows it can be used to output electricity. Elementary science at it's best. If any of you have took them apart you'd notice it draws eletricity from touching the center metal pole. Two little brush/copper/zinic contacts. Basically I've been trying to think of ways to extract eletricity without having a need for them. They cause friction. Uh-oh, a few lightbulbs lit up in peoples minds by now and they're going "oh no not another person trying to beat the laws of thermodynamics and acheive perpetual motion" Yep. As we all know eletricity CAN jump if it's powerful enough and arc, but this doesn't make it too safe either. However it's a small scale model to start out and can be contained so the arc won't be a problem. My other problem is the calculations. They need to be precise. To get it working I need a low rpm generator that will generate high output. For this it requires torque which kinda kicks me, it will also need to use (I assume) rare earth magnets. So basically lets stick with my latter problem since it's more down to earth. I need a fairly small generator if possible (It can be larger if no other solutions are present) At least the size of a walnut I don't plan to make anything immense in size as I lack the funding. As pointed, small is key. Not to be redundant but to paint a clearer picture. It will also need to generate decent voltage at a low rpm speed. I cannot emphasis this enough because it's one of the key parts to make my idea function. Hum... Yeah that about covers it. So if any tech wiz's are out there that know of such thing I'd apperecaite it if you'd part the knowledge to me :P I'm also very aware that perpetual motion is eh, impossible... by current standards. The intention of this project is to deepen my knowledge and figure out why things won't work, figure out solutions and on so forth. A learning project for now and perhaps one day it might become something far more awesome.

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Dark-half (author) 10 years ago
I suppose that's one problem solved. Changes the center of mass so I'm a little worried how that'd affect the RPMs but inturn it actually works with the general idea. By the way the last few steps don't show up for the gen. I do get the concept however. They sure do like their resin hehe. I still need the whole low rotations/high output. I can't get it to work unless it generates decent eletricity in just a few rotations. Evidently rare earth magnets are best, for sure. I've been reading up on them being used in a generator configuration and it seems alot of them have a problem, a fatal one infact heat generation, bad heat generation. Looks like I'm going to have to employ some heat sinks or creamatics to bleed it off... Those little things you stuck on yer CPUs and the compound you use to adhesive it stuck seems to be a prime idea to employ. Erm, yeah.... Here's the basic idea of my concept. You got a disc that spins, at the edge are plates or magnets as it spins it generates electricity obviously. Now the electricity is funneled from the center as per the new design/idea then you got that converted into soft magnetic pulses that will push or pull at the very edge of the disc and hopefully build up kinetic energy to continue the cycle a couple more times. Ideally if I could find a way to have a stable levitation that requires no power source and just cleverly placed magnets to /pin/ the disc on an axis and stick it in a vacuum chamber in theory I would have perpetual motion as there would be completely zero friction, but you got to deal with entropy. Can't get more out of it than you input into it right?
10 years ago
You're just not going to get high output with low input. Energy doesn't work that way. If you increase the size/power of the magnets and/or increase the winding, you will increase the output of the generator and, at the same time, increase the amount to energy needed to turn the generator. As to a motor/generator combination, in a vacuum with no friction, you still have loss converting mechanical energy to electical energy and back. Since there is loss, it will not be perpetual. Even if you were to wire the device entirely with 24K gold wire, there would still be loss.
Dark-half (author)  LasVegas10 years ago
That's really too bad. I guess that's why I've been having trouble finding one on the net. I've seen a couple that boast the low rpm - high output claim, but the sites didn't seem too crediable. I suppose a better goal to aim at than perpetual motion is sort of a type of energy that will last awhile after the intinal input -- we got those crank magnet thingies in flashlights and radios. Those are perfect examples but you can't really employ them into a vehile. Well... you can but I don't think it'd worth the effort of cranking portioning to how far it would go. with all the technology we have vehicles seem rather rudimentary compared to everything else. They still run on fossil fuel. I'm sort of straying off topic here but it was the ultier motive behind learning about making clean efficent energy and all sorts of fun things.
10 years ago
As BoomGuy said, those devices do indeed use "SuperCaps" that charge after 30 seconds or so of hard cranking of the generator (or shaking in some cases). This uses quite a bit of human energy to charge the capacitor and then powers a very low current device for about 20X the time spent generating the power. You could eliminate the battery/capacitor and power the LED with just the generator and it would work with 1/20th the cranking power, but any extra cranking would go to waste (heat/drag) and the moment you stop cranking the LED would go out. So think of the battery/capacitor as a reservoir for the energy.
10 years ago
Dude, those flashlights use LEDs. A coil and magnet to generate electricity. A capacitor to store the electricity. By a quick search for LEDs and a quick back of the envelope calculation a ten LED flashlight only uses 1 Watt. Essentially the capacitor is a tiny rechargeable battery. The energy doesn't "last a while". It's just stored.
VIRON10 years ago
Look inside of various bad disc drives for brushless motors that can also generate useful power especially if diodes turn it into DC. Some have hall effect sensors like fans. Those have to be bypassed.
lemonie10 years ago
LasVegas10 years ago
An arc is actually going to burn off more power than the drag of brushes would. The light of the arc and heat generated is all wasted power. You also need to generate a rather high voltage to acheve an arc of any feasable distance. Mush higher voltage then a walnut size generator
Tool Using Animal10 years ago
spin the magnets around a stationary coil, rectify the output.