Biochar is a carbon-rich material produced by heating biomass in a low-oxygen environment. This process, called pyrolysis, transforms part of the biomass carbon into stable aromatic structures that resist rapid decomposition.
When the feedstock would otherwise decay or be burned and the resulting biochar is placed in an eligible long-term use, the activity can generate carbon removal certificates.
The carbon accounting chain
A biochar project begins with feedstock eligibility. The methodology tests source, moisture, alternative fate and transport. The production calculation then accounts for energy use, process emissions, methane and nitrous oxide where relevant, and the fraction of carbon retained in the final product.
Laboratory analysis measures properties such as organic carbon content and hydrogen-to-carbon ratio. These values help determine stability and the quantity of durable carbon stored.
Durability depends on production and use
Not all char is equivalent. Temperature, residence time, reactor control and feedstock characteristics influence stability. The final application also matters. Approved soil, construction or other storage uses need traceability and controls that prevent the material from being burned or otherwise destroyed.
Methodologies apply conservative durability factors and deductions rather than assuming every tonne of carbon remains stored indefinitely.
MRV at batch level
High-quality projects track feedstock receipts, production conditions, energy consumption, output mass, laboratory results and final use for each eligible batch. Digital systems can connect these records to unique certificates and independent verification.
This production-level evidence is one reason biochar has become a leading form of delivered durable carbon removal.
Buyer questions
Buyers should review feedstock sustainability, additionality, net energy balance, technology performance, end-use contracts and the methodology's durability assumptions. They should also distinguish current operating capacity from future scale.
Dark Earth applies this approach inside Singapore's urban organic waste system, creating traceable biochar removals from locally available residues.
