On Thu, 24 Jun 2004 03:51:08 -0500, Richard J Kinch
wrote:



A 25% efficient 5 HP lawnmower engine
dissipates more heat than that, with far less surface area.

Perhaps, but it has the advantage of blowing most of that heat out the
exhaust, instead of raising itself to a temperature that blackbody radiates
it.

Good point. The engine also has forced-air cooling on the fins.
Still, those magnets are pretty big so there's lots of area for
convection air cooling.

To your first point, we don't know that the magnet draws 10KW, only
that it was driven by a generator capable of 10KW. How much power
the magnet really draws is indeed a relevant question.