Primitive Technology demonstrated how to make charcoal using the “mound method” by encasing a large pile of wood in mud and then lighting it on fire.
I made a batch of charcoal using the mound method then stored it in baskets for later use. Charcoal is a fuel that burns hotter than the wood it’s made from. This is because the initial energy consuming steps of combustion have taken place while making the charcoal driving off the volatile components of the wood (such as water and sap). The result is a nearly pure carbon fuel that burns hotter than wood without smoke and with less flame. Charcoal was primarily a metallurgical fuel in ancient times but was sometimes used for cooking too.
Earlier this year, Primitive Technology demonstrated how to build primitive cord drills and pump drills which could be used to start fires or drill holes.