Since bigsleep's anno, below I have been pondering the
frictionless conversion of mechanical into heat energy.
In
lots of places, deforestation is driven by need for cooking
fuel. Cooking over wood or charcoal is smoky and slow.
If
there could be a pedal powered hot plate that would
never
wear out this would be a huge boon.
This would be a plate affixed to magnets that would spin
like a potters wheel. I suspect faster spinning would be
better and there would be a pedal or crank. The
simplest
version would be a stand over the spinning magnets
(maybe
enclosed in plastic to keep them clean) on which you
would
put your pan or wok. The pan would be heated via
induction and you would cook.
One level up of complexity involves an element designed
to
be heated well by induction. It seems like people use
aluminum. Wouldn't nichrome be better? It is an alloy
which heats up a lot with current. The pan would sit
atop
this.
Third level of complexity would be a heat reservoir. For
most cooking the wok or pan is itself the heat reservoir.
It cools off fast when you put the food in. This
reservoir heats up and then stays hot as you cook, so you
don not need to pedal the whole time. You could get
one
of the kids to spin it up to heat while you prepare
ingredients.
Bonus: no flames means no smoke and much less fire
risk.
Bonus 2: Moving parts could be bike parts: easy to fix
almost anywhere in the world. The magnets could be
speaker magnets: easy to replace if the field got weak
with age.
Problem: I do not have a good feel for the amount of
energy needed to heat a pan vs the amount easily
generated by a pedal. If you would need to pedal for
hours
to get the pan hot that would not be good.
//creating a large drag on the rotor and heating
the
plate//
A regenerative system could make a nice cup of
tea.
— bigsleep, May 31 2015
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