Scaling to Gigatonnes

How much biomass exists—and how much can we use? Global estimate: ~120 billion tons of dry biomass annually from agriculture, forestry, and waste streams. But not all is available. Crop residues needed for erosion control, livestock feed competes with energy uses, and collection costs rise with distance. Practical availability: ~30-40 Gt/year without ecological harm.

Converting to biochar: yields 25-40% by weight. If we pyrolyzed 10 Gt/year at 30% efficiency → 3 Gt biochar. Each ton contains ~0.7 t carbon, equivalent to 2.6 t CO₂ sequestered for centuries. Result: ~8 Gt CO₂/year removal at 10% of feedstock potential. For context, global emissions (2023) were 37 Gt CO₂—biochar could offset 20%+ at scale.

Geographic distribution matters. Asia holds 40% of feedstock (rice husks, sugarcane bagasse), Africa 20% (crop residues, savanna biomass), Americas 25% (corn stover, forest thinnings). Deployment must match local feedstock, soil needs, and infrastructure. Kenya's Kakuzi farm uses coffee husks → biochar → coffee plantations (closed loop). India's rice-growing states could produce 50-100 Mt/year from straw burning alone.

Economic viability unlocks scale. At $500/ton biochar + $50/ton CO₂ carbon credits, revenues exceed costs for medium-large operations. But policy support needed—subsidies, streamlined permitting, ag extension services teaching farmers application methods. IPCC models include 0.5-2 Gt CO₂/year biochar removal by 2050 in 1.5°C scenarios—technically feasible, economically viable with right incentives.