[Stoves] Turn down by moving the pot

[Crispin Pembert-Pigott]

Dear Teddy and Kevin

 

The most common 'old' method was to have an opening on the stove top (rings)
which were removed to expose the pot bottom to the fire for high power
cooking and to put the ring or disk back in order to turn it down. Placing a
metal plate on top of a metal cooking surface between the pot and stove
accomplishes the same thing, giving 'even heat' (which is a good point to
highlight). 

 

Clearly this lowers the fuel efficiency of cooking, but it may not matter if
a) the stove is really fuel-efficient, b) if the fuel is easily available
and reducing consumption is not a priority or c) if there is some other
benefit such as space heating that is desired at the same time. 

 

The last case prevails in Mongolia during the 9-month heating season. The
cooking efficiency (which ranges from 15-25%) is barely considered as the
main task is heating. Some stoves are not used for cooking at all.

 

In some areas of Indonesia the main daily cooking task is evaporating water
to make palm sugar so that continues at high power while the cooking is done
on secondary or tertiary pots. Those additional pots are used together with
rings and plates to control the power reaching them. Some stoves have a
moveable baffle that directs the hot gases upwards, either more or less.

 

The point is of course, to control the cooking power to suit the meal being
prepared. It is important that stove designers are aware that there is no
specific requirement to control the fire itself 'enough to reduce the
cooking power over the range of 4:1' (for example) just a requirement that
such a reduction can be engineered by the cook using the facilities of the
stove.

 

Regards

Crispin

 

 

 

Dear Kevin, 

 

Thank you very much for this, I have been thinking about that quite alot in
regards how people in Kenya (and E.A) cook ugali (a polenta maize flour type
of food). It starts out liquid but ends up a solid - how much will the size
(diameter) of the source contribute to cold/hot spots during this
conversion? Is a graduated turn down function or a simple high/low better
for controlling this? 

 

Thanks, 


Teddy 




Cookswell Jikos



 

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