In Africa charcoal is normally produced by cutting down trees, setting them on fire, and tossing on earth. After smoldering for days, enormous amounts of charcoal are created. But this contributes to deforestation and greenhouse gasses. By using solar to “cook” agricultural waste (corn stalks, coconut husks, etc.) we can make charcoal without burning or destroying forests. Charcoal does make CO2 when burned, but (unlike gas or oil) it was created by a modern-day plant removing CO2, so the net carbon is zero. Agricultural waste that is buried produces methane, which is far worse as a greenhouse gas. Charcoal in contrast can be buried as a soil supplement, which means the net carbon is negative–the farmer is actually removing it from the air.