Ithaka Institut

Dig your own soil Kon-Tiki

Biochar can be produced without any investment and with only natural construction materials. Dig a conical pit in the form of a Kon-Tiki, ram the clay, level stones as a upper rim shield around the pit and start barely one hour later to produce your first own biochar.

The production of biochar in soil pits or tranches is an old technique several thousand years old. Before we started at the Ithaka Institute to develop Kon-Tikis made from steel, we conducted our first trials and gained experience with making biochar in soil pits.  Certainly, there are several disadvantages compared to the regular steel Kon-Tiki: You cannot quench with nutrient enriched liquid from the bottom and it's difficult to recover the quenching liquid. As the clay wall of the soil pit is an insulator and not a reflector, the temperature in the soil pit kiln is less homogeneous and the combustion of pyrolysis gases is less optimal. But all these are no relevant disadvantages when you can't afford to build a steel Kon-Tiki. In the following presentation, you find the instructions how to build a Kon-Tiki with a shovel and how to make your first biochar in it.