The methodology you choose shapes everything downstream — how you measure, what you can claim, which buyers you reach and what price you achieve. Here is how the leading biochar pathways compare.
The shortlist
For durable biochar removals, four standards dominate: Verra VM0044, Puro.earth, Isometric and Gold Standard. Most projects we advise focus on the first three.
Verra VM0044
VM0044 covers biochar utilisation in soil and non-soil applications. Verra's scale and brand recognition give credits broad market acceptance, and the methodology accommodates a wide range of feedstocks and end-uses.
- Strengths: market familiarity, breadth of applications, large buyer base.
- Consider: rigorous documentation and validation expectations.
Puro.earth
Puro.earth issues CO₂ Removal Certificates (CORCs) and was an early mover in durable removals. Its biochar methodology is well understood by corporate buyers focused specifically on engineered/durable CDR.
- Strengths: strong durable-removal positioning, established buyer relationships.
- Consider: platform-specific processes and supplier onboarding.
Isometric
Isometric is a science-first registry with a transparent, public protocol and heavy emphasis on measurement rigour. It appeals to buyers who prioritise scientific defensibility.
- Strengths: transparency, scientific credibility, high-quality buyer pool.
- Consider: demanding MRV and data requirements.
How to choose
Work through these questions:
- End-use. Soil application, construction materials, or both? Some methodologies handle non-soil uses more readily.
- Buyer demand. Which credits do your target buyers prefer to purchase?
- MRV capacity. How much measurement and data infrastructure can you realistically support?
- Timeline. How quickly do you need issuance, and what are the validation lead times?
- Permanence claims. What durability can your biochar's H:Corg ratio credibly support?
The role of H:Corg
Across every methodology, the hydrogen-to-organic-carbon (H:Corg) ratio is central to permanence. A ratio below 0.7 is generally associated with centuries-scale stability; below 0.4 with longer durability still. Production temperature and conditions drive this number, so technology selection and methodology choice are linked.
Our take
We are methodology- and vendor-neutral. In practice, we model two or three pathways for a project, compare expected issuance, cost and buyer fit, and recommend the one that maximises both integrity and value.
If you would like that analysis for your project, start with a feasibility assessment.