I have been experimenting with small wood stoves lately & stumbled across a "new" type called "Inverted Downdraft Gasifier " stoves.
Although the theory of opperation is counter intuitive (top lit, burns top to bottom) it works in practice.

Easy to make, very efficient, low to no cost... I made one and was quite supprised.

Burn time, about 1/2 hr., on a handfull of twigs !
Boil time, 1pt. water 6 - 12 min. depending on fuel used ect.
Weight, 2 - 3 oz.
Almost no smoke !

A simple design avalible at.

web page Wood Gas Stove





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