Ken Sterling writes:

A fella runs a junk yard and has a crane with an electro-magnet for
moving scrap metal - he uses a 10,000 watt DC generator to power the
magnet.

Someone might have abstract ideas about doing this by rectifying an AC
generator, or a similar scheme. But 10 KW is a lot of power and it isn't
so simple to just hook up a few parts and have it work for long. Does this
thing really use that much ooomph? Where does all the heat go?