Hi: I'm interested in making biochar in my 1/4 acre. After looking at various design, it looks like the cone pit / trench method will work best, but I don't have the room to dig a large trench. I'm wondering if anyone has tried this approach that Edible Acres on YT (
https://www.youtube.com/watch?v=lOSDwp20EKM) used: Take a used metal drum and cut it open, and use it as an "above ground" trench. Add material as it burns and drench out the fire at the end, just like the cone pit or trench method.
Thoughts? I'd love to hear your advice!