whats witchcraft have to do with engines?
Some people claim that they really run on black magic. B-)
Seriously, though. The SITE may be a witchcraft site, but
the ARTICLE is about a (recently completed?) military
project to design a miniaturized diesel generator.
It's intended to replace the $100 disposable one-day-capacity
battery used to power the electronic warfare gear carried by
modern US soldiers.
Personally I think it's a rotten idea for soldiers. Batteries
are silent, while this thing, though "significantly quieter" than
a diesel model airplane engine, is not. Bad for stealth missions.
Diesels emit exhaust, which can easily kill a soldier in an enclosed
environment. Diesels create several times as much heat energy as
output power, making the soldier a much bigger IR target and also
imparing his efficiency in a hot environment. Diesel exhaust leaves
a characteristic odor that lingers, again making him more detectable,
both where he is and where he has been. And so on.
If they want to replace the single-use batteries with something
refuelable, liquid-fueled fuel cells would, IMHO, be a much better
choice.
But for other uses than powering the wearable gear - like a
man-portable power supply for equipment that gets set up in
remote locations - it makes good sense. And for non-military
applications ditto.