I ran across this idea in reading links on the 'terra preta' soils. That discussion aside, making charcoal out of yard debris rather than composting it appeals to me so I have started building an oven.
So far, I have a 2 foot length of black-painted galvanized steel stove pipe as the vessel which is suspended at the parabolic trough's focal point. (Photo attached below).
As I have a bit of work to do building the trough, I don't want to make it too small and so not achieve the 450F to 500F temperatures I need inside the tube. So, any ideas of how big I need to build the trough? The width I have fixed at 20"; this gives the pipe 4" of extension to accomodate further modules.
Parts/costs: 4" diameter galvanized steel stovepipe ($4.49), & a galvanized steel cap ($2.79), both painted with high-temp flat black paint ($2.19). Yard stick marked in inches for scale.
Drawings & links to come.
