Captain Drawdown’s daily logbook on every CDR story, paper, and expert voice — so you don’t have to read them all.
Why this matters now
Biochar is currently the highest-volume durable carbon dioxide removal credit category by tonnes issued, and most of those credits are certified under one document: Verra’s VM0044. That methodology is now open for a revision, and the choices Verra makes in this drafting window will set the permanence and quantification math for a large share of the durable CDR market for years. If you sell, buy, or verify biochar tonnes, this is the moment the numbers get decided.
What is it?
VM0044 is Verra’s Verified Carbon Standard methodology titled “Methodology for Biochar Utilization in Soil and Non-Soil Applications.” It defines how a biochar project quantifies removed CO2: what feedstocks qualify, how you estimate how long the carbon stays put (the permanence factor), how soil applications are treated versus non-soil uses like concrete or asphalt, and what counts as the baseline scenario. Every credit issued under VM0044 traces back to the formulas and default values inside that document.
Who is involved?
Verra, the standard-setter, runs the consultation and ultimately approves the revised text. Project developers producing biochar credits, verification bodies auditing them, and buyers (corporates, brokers, and portfolio managers like CUR8 and Frontier Climate) are the constituencies whose economics move with the numbers. Researchers publishing on biochar recalcitrance and soil interactions provide the empirical basis Verra can lean on, or ignore.
What just happened?
Verra has opened a public consultation on a revision to VM0044, covering biochar in both soil and non-soil applications (Verra methodology revision page). The revision arrives against a backdrop of new science pointing to quantification gaps in current frameworks. A recent CDRXIV preprint reports that cation trapping by biochar in soils can reduce net atmospheric CO2 uptake relative to what standard accounting assumes (Ahmed et al., CDRXIV). Long-duration field data on biochar’s behavior in soil is also finally arriving, including a 14-year study I covered recently (Captain Drawdown). Separately, Rainbow Standard has announced that Frontier Climate approved its Biogenic Carbon Capture and Storage methodology, which Rainbow describes as aligned with the EU Carbon Removals and Carbon Farming (CRCF) framework (Rainbow Standard, LinkedIn). Buyer-side alternatives to VM0044 are multiplying while VM0044 itself is being rewritten.
Open questions to track
- Does the revised VM0044 replace flat permanence defaults with tiered factors tied to feedstock, pyrolysis temperature, and end-use, or keep a single average?
- How does Verra treat soil interaction effects such as cation trapping, priming, and mineral-associated carbon that recent literature has flagged?
- Are non-soil applications (concrete, asphalt, filtration media) given distinct permanence and monitoring rules, or folded into the soil framework?
- Who submits public comments, and what do the largest incumbent issuers argue for? Public comment letters will make the political economy visible.
Further reading
- Verra: VM0044 revision consultation page — the primary document and comment portal.
- Ahmed et al., “Cation trapping by biochar reduces carbon removal efficiency,” CDRXIV — the accounting critique the revision has to engage with.
- McMahon, Brown, Daugaard: feedstock moisture and biochar recalcitrance dataset — process-level data relevant to differentiated permanence factors.
Biochar credits are load-bearing infrastructure for the durable CDR market right now. Whatever VM0044 says next will either extend that role or shrink it. The consultation is where that gets decided, in writing, on the record.
Citations
- Verra — Verra methodology revision page
- Cdrxiv — Ahmed et al., CDRXIV
- LinkedIn — Rainbow Standard, LinkedIn — LinkedIn post
- DOI-resolved paper — McMahon, Brown, Daugaard: feedstock moisture and biochar recalcitrance dataset