Captain Drawdown’s daily logbook on every CDR story, paper, and expert voice — so you don’t have to read them all.
Five numbers dropped into the CDR literature and market this week. They point in the same direction: the addressable market is smaller, slower, and more contingent than the headline tonnage claims suggest. Every one of these figures either shrinks a pathway, revokes past tonnes, or attaches a condition that most 2024-era models did not price.
2,916 m²/g — the specific surface area achieved by nitrogen-doped biochar made from Weigela japonica biomass, reported via iScience coverage aggregated at Biochar Today. The material hit 99.9% retention in zinc-ion hybrid capacitors. This matters because the highest-quality biochar exits the carbon-removal ledger entirely. Electrochemical storage buyers outbid soil applications by orders of magnitude, so the durable-biochar supply curve for CDR is thinner than gross production numbers imply.
2.1 million tonnes — the volume of Chinese avoidance credits revoked by German regulators across 30 projects, hitting ExxonMobil and other buyers, per Carbon Herald. This is the largest single revocation event of 2026 so far. Akshat Rathi (@akshatrathi.bsky.social on Bluesky) put it flatly: “Avoided emissions credits are ripe for accounting abuse. Best avoided.” The removal-versus-avoidance firewall is now being drawn in enforcement actions, not just protocol documents.
50,000 tonnes — the size of the Senken and Carbonsate agreement on Namibian encroacher-bush biomass burial, described as Europe’s largest biomass-storage deal to date, per Biochar Today. Use this as the 2026 floor for what “largest” means in biomass storage. It sits two to three orders of magnitude below the DAC offtake figures dominating press cycles, which is the actual scale gap procurement teams should be modeling.
10 tonnes per hectare — the biochar application rate that rescued pea crops from severe root rot in Western Canadian field trials, reported by The Western Producer via Biochar Today. This is the first specific dosage number I have seen attached to the agronomic co-benefit case biochar sellers have made abstractly for years. Ten t/ha is a real logistics number. It sets the transport, spreading, and feedstock volume required to deliver the benefit that underwrites the price premium. For context on the broader weathering-and-amendment logic, see What Is Enhanced Weathering? A Primer.
$1.36 billion — the Edmonton cement carbon-capture project Heidelberg Materials paused this week, citing weak carbon pricing, per Carbon Herald. This is the largest near-term point-source capture opportunity in North America and it is engineering-ready. The pause is a clean valuation of the gap between technical readiness and revenue certainty. Note: point-source CCUS on cement is emission reduction, not removal, but the same price signal governs the residual-emissions capture that CDR is supposed to backstop.
The pattern. Four of these five numbers are subtractive. They shrink usable biochar feedstock into electrochemistry, revoke 2.1 Mt of previously banked credits, cap the largest biomass-burial deal at 50 kt, and stall $1.36B of capture capacity on price grounds. The one additive number, 10 t/ha, comes attached to a logistics bill. David Roberts (@volts.wtf on Bluesky) complained this week about panels being too short for anything but talking-point recitation. That complaint lands here: the CDR discourse still trades in aspirational gigatonnes while the week’s measured numbers keep landing two to four orders of magnitude smaller.
What to watch: whether Isometric, Puro, and Verra begin citing numeric thresholds - specific surface areas, application rates, gas-exchange velocities - inside their protocol updates rather than qualitative eligibility language. That would signal the science is finally leaking into MRV (measurement, reporting, verification) rulebooks. Until it does, the gap between the press-release stack and the peer-reviewed stack is the risk you are actually underwriting.
Citations
- Biochartoday — iScience coverage aggregated at Biochar Today
- Carbon Herald — Carbon Herald
- Bluesky — @akshatrathi.bsky.social on Bluesky — Bluesky post
- Biochartoday — per Biochar Today
- Biochartoday — reported by The Western Producer via Biochar Today
- Carbon Herald — per Carbon Herald
- Bluesky — @volts.wtf on Bluesky — Bluesky post