> >BUT it may be easier to simply use a fixed magnet and rotate a coil past it
> >to generate voltage.
>
> In this case, where does the power come from?  I know it'll work, but I'm
> having trouble working out the source of the energy.  Does it come from
> the fan, indirectly?  If we increase the load on the coil, does the current
> draw of the fan increase?  This may require some experimentation...

The power comes from the movement between the coil and the magnet. The moving
part will experience a "resistance" because of this. So yes, the fan motor
will need to be stronger than otherwise to do this.
--
D. Jay Newman           !
jay@sprucegrove.com     ! Xander: Giles, don't make cave-slayer unhappy.
http://enerd.ws/robots/ !

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