
Biochar Quality Is the CDR Field's Credibility Problem
Biochar is frequently cited as one of the most cost-competitive carbon dioxide removal pathways. Costs of $50–200 per tonne CO₂ are achievable at scale — far below direct air capture at $400–1,000+ per tonne, and competitive with enhanced weathering at larger deployment volumes. But there’s a catch: not all biochar is equal. The gap between high-quality and low-quality biochar is large enough to determine whether a buyer is purchasing centuries of durable carbon storage or a product that will degrade meaningfully within decades. ...








