What is a biochar cook stove

It is a cook stove that uses very little wood for the amount of heat that is generated. The wood itself does not burn, but the gas (smoke) that the hot wood releases is burned, which gives it the intense heat. At the end of the burn process pure carbon is left behind. Because the gas (smoke) is burnt the carbon particulates that are released into the air are negligible and do not contribute to the carbon particulates in the air that conventional fires release, and are therefore better for the environment. The carbon (biochar) that is left behind can then be added into the soil, thereby sequestering carbon. It can also be charged with bacteria, can hold onto moisture and air, which are the main components of what makes healthy soil.



There are so many variables in making a biochar cook stove, so there is no way to give a precise list of materials. So I will list some of the most common ways I have made them.

Normally I make them using 4 separate parts

  1. Burn chamber
  2. Surround for airflow
  3. Chimney
  4. Pot stand

1. Burn chamber

Often this can be a steel drum (between 20 and 100 litres
Do not use galvanised steel, as this is toxic when heated
Example image of a burn chamber (on facebook)
Using a gas bottle as a burn chamber (on facebook)


2. Surround for airflow

Either this can be a drum, that is larger than the burn chamber or we can use a metal sheet to make a surround
Example of a corrugated metal sheet (on facebook)

When using a sheet to make the surround airflow, we need to make a lid to sit the chimney onto
Example lid (on facebook)

Example 1 of a drum (on facebook)
Example 2 of a drum (facebook)
In both cases of using a drum, we added the chimney to the drum


3. Chimney

The diameter of the chimney should be approximately ⅔ the diameter of the burn chamber

See previous pics for examples of chimneys


4. Pot stand

Again there are so many ways this can be done. I prefer to have a pot stand which has a sheet around the pot which forces the heat to hit the side of the pot, hence the pot sits inside. Not sure how to explain this, so just look at the pictures ;)

Pot stand using rebar to sit the pot onto (on facebook)
Another variation of a pot stand (on facebook)



Biochar cook stove examples on google photos
Biochar cook stove examples on facebook