Welcome to the first CaptainDrawdown roundup — a regular digest of what’s happening across the CDR landscape. Let’s dive in.

🏭 Direct Air Capture

Climeworks’ Mammoth plant is operational in Iceland. The world’s largest DAC facility, with a nameplate capacity of 36,000 tonnes CO₂/yr, has been ramping up since it began operations in May 2024 (Climeworks, 2024; Reuters, 2024). Early operational data suggests the modular design is performing as expected, and Climeworks is already planning the next generation of larger plants. The big question remains cost — the company targets around $300/tonne by 2030 (CNN, 2024).

1PointFive’s Texas project continues to scale. Oxy’s DAC subsidiary, using Carbon Engineering’s liquid solvent technology, is building what will be the largest DAC facility in the world. When fully operational, it aims to capture up to 500,000 tonnes CO₂/yr (Carbon Engineering, 2022; Oxy, 2024). The project benefits from the US 45Q tax credit, which offers $180/tonne for DAC with geological storage (IRA Section 45Q; Carbon Capture Coalition, 2025).

🪨 Enhanced Weathering

Field trial data keeps coming in. Multiple enhanced weathering companies — including UNDO, Lithos, and Eion — have been publishing results from multi-year agricultural deployments. The emerging consensus: basalt application rates of 20-50 tonnes/hectare can sequester 0.5-2 tonnes CO₂/hectare/year, with measurable co-benefits for soil pH and crop yields (Amann et al., PNAS, 2024; Beerling et al., Nature, 2020). MRV (measurement, reporting, and verification) remains the biggest challenge, but methodologies are maturing fast (Calabrese et al., Nature Reviews Earth & Environment, 2025).

Carbon credit demand is growing. Enhanced weathering credits are attracting interest from corporate buyers looking for durable removal with co-benefits. Prices currently range from $80–200/tonne for the underlying removal cost, though credit prices from ERW providers average over $200/tonne depending on the provider and verification methodology (Sylvera, 2025; cCarbon, 2025).

🌊 Ocean CDR

Ocean alkalinity enhancement gets serious attention. Several startups — including Planetary and Vesta — are running pilot projects to test adding alkaline minerals to ocean waters. Research in Nature Communications Earth & Environment (2025) describes OAE as having “gigatonne-scale potential” for atmospheric CO₂ removal, though more research on ecological impacts and monitoring frameworks is needed (Subhas et al., Comms Earth & Env, 2025).

📜 Policy & Markets

EU Carbon Removal Certification Framework (CRCF) advancing. The EU is building the regulatory infrastructure for certified carbon removals, which will be critical for creating demand and ensuring quality. The framework distinguishes between permanent removals, carbon farming, and carbon storage in products. In November 2025, the Commission adopted Implementing Regulation (EU) 2025/2358 on certification schemes, with first certifications expected throughout 2026 (European Commission, 2025; CarbonGap CRCF Tracker).

Voluntary carbon market stabilizing. After a turbulent 2023-2024 period of scrutiny and quality concerns, the voluntary market for carbon removal credits is showing signs of maturation. Buyers are increasingly sophisticated, demanding high-quality MRV and favoring durable removal methods over avoidance credits.

📚 Research Worth Reading

  • “Potential for large-scale CO₂ removal via enhanced rock weathering with croplands” (Beerling et al., Nature, 2020) — Modeling suggests 2–4 GtCO₂/yr potential at costs of US$80–180/tonne, concentrated in tropical and subtropical regions. doi:10.1038/s41586-020-2448-9
  • “Long-term stability of biochar in soil systems” — Meta-analyses and reviews confirm biochar carbon persistence of hundreds to thousands of years in most soil conditions, with mean residence times around 556 years for recalcitrant components (Wang et al., Agronomy, 2021; Kalu et al., Frontiers in Soil Science, 2024)
  • “Direct air capture cost projections” — Multiple analyses suggest DAC could reach $200–250/tonne by 2050 with aggressive scale-up, though the $100/tonne target remains challenging (Belfer Center, Harvard, 2023; Forbes, 2024)

That’s the snapshot. I’ll be doing these roundups regularly — tracking the startups, the science, and the policy moves that are shaping the CDR industry.

Want me to cover something specific? Find me on Bluesky, X, or Mastodon.

Until next time. 🌍

Sources

  1. Climeworks (2024). “Climeworks switches on world’s largest direct air capture plant Mammoth.” climeworks.com
  2. Reuters (2024). “Climeworks opens world’s largest plant to extract CO2 from air in Iceland.” reuters.com
  3. CNN (2024). “‘World’s largest’ plant to suck carbon out of the air.” cnn.com
  4. Carbon Engineering (2022). “Construction of Direct Air Capture in Texas.” carbonengineering.com
  5. Occidental Petroleum (2024). “1PointFive’s South Texas DAC Hub Awarded DOE Funding.” oxy.com
  6. Carbon Capture Coalition (2025). “The One Big Beautiful Bill Act — 45Q Fact Sheet.” carboncapturecoalition.org
  7. Congressional Research Service. “The Section 45Q Tax Credit for Carbon Sequestration.” congress.gov
  8. Amann, T. et al. (2024). “Enhanced weathering in the US Corn Belt.” PNAS. doi:10.1073/pnas.2319436121
  9. Beerling, D.J. et al. (2020). “Potential for large-scale CO₂ removal via enhanced rock weathering with croplands.” Nature, 583, 242–248. doi:10.1038/s41586-020-2448-9
  10. Calabrese, S. et al. (2025). “Challenges and opportunities in scaling enhanced weathering for CDR.” Nature Reviews Earth & Environment. doi:10.1038/s43017-025-00713-7
  11. Sylvera (2025). “Carbon Offset Pricing Trends: What Buyers Should Budget for in 2026.” sylvera.com
  12. cCarbon (2025). “CDR Series: Enhanced Weathering And Mineralization.” ccarbon.info
  13. Subhas, A.V. et al. (2025). “Effects of ocean alkalinity enhancement on plankton.” Communications Earth & Environment. doi:10.1038/s43247-025-02248-7
  14. European Commission (2025). “Carbon Removals and Carbon Farming.” climate.ec.europa.eu
  15. CarbonGap. “EU CRCF Explained.” tracker.carbongap.org
  16. Wang, J. et al. (2021). “Soil Organic Carbon Sequestration after Biochar Application: A Global Meta-Analysis.” Agronomy. doi:10.3390/agronomy11122474
  17. Kalu, S. et al. (2024). “Biochar – a sustainable soil conditioner.” Frontiers in Soil Science. doi:10.3389/fsoil.2024.1376159
  18. Belfer Center, Harvard Kennedy School (2023). “Prospects for DACCS: Costs, Scale, and Funding.” belfercenter.org
  19. De Luna, P. (2024). “Will Direct Air Capture Ever Cost Less Than $100 Per Ton?” Forbes. forbes.com