Biochar is a charcoal-like material created by heating plant matter without oxygen. It is a powerful, net-negative cleantech solution that sequesters carbon, improves ecosystem health, and has dozens of uses, from fertilizer to insulation to water decontamination. A new report from Boulder-based cleantech venture capital and research firm Saoradh Enterprise Partners (SEP) analyzes opportunities in the biochar market and identifies the most investable companies.