On Wednesday of GOAT 2024 we had a small but lively conversation around durable carbon removal with a group of 3-4 folks. Here’s a summary of the notes and resources discussed during that session!
Facilitator: @clevinson
Attendees: @alexbourlier, Sarah Olimpia, Michael Fernandez, @AaronH
Topic: Durable Carbon Removal in agricultural systems (Biochar / Enhanced Rock Weathering)
Carbon Removal vs Carbon Markets
We started the conversation with some background and overview of carbon removal. One key element of this is that “carbon removal != carbon markets”. Private carbon markets and carbon credits are one way of funding carbon removal or avoided emissions, but when speaking about “Carbon Removal”, the conversation was more about the different activities & pathways for reducing CO2 from the atmosphere, independent of the funding mechanisms (e.g. compliance / State mandated systems vs private markets).
Backlash in Voluntary Carbon Markets, and the shift to “Carbon Dioxide Removal”
We discussed how the traditional voluntary carbon market has continued to receive bad press, as showcased in this Guardian Article from Jan 2023, after which prices fell for many forest carbon projects and many corporates pulled out of purchasing such credits.
Over the next several months, a large shift in focus (led my leading tech corporates such as Microsoft, Stripe, Meta, Alphabet, McKinsey) occurred – where the voluntary carbon markets industry claiming that “durable” or more permanent carbon removal projects, with higher quality MRV (monitoring reporting & verification) would be necessary moving forward.
Public & Private funding of Carbon Removal
Several tech corporates launched Frontier Climate, as a funding vehicle for this new category of “durable/permanent” and high quality carbon removal projects. And the industry largely rebranded itself away from avoided emissions (such as incentivizing forest conservation to protect from deforestation) in favor of “carbon dioxide removal” (or CDR for short) as an umbrella term for this activity.
Microsoft & Frontier have been by far the largest purchasers of durable carbon removal to date.
In addition to private funding, the US government has engaged in direct procurement or funding of research for carbon-dioxide removal:
- DOE announced $1.2MM in funding for carbon removal, mostly focused on Direct Air Capture (May 2024)
- ARPA-E announced $36MM in grants to support research in Marine CO2 removal (Oct 2023)
- USDA has published articles on Enhanced Rock Weathering to build literacy amongst farmers
- Yale & Georgia Tech received $4.9MM in funding from USDA to support with direct assistance of implementing enhanced rock weathering for small-scale farmers, as part of Partnership for Climate Smart Commodities
Similar grants & funding programs have existed in Europe as well.
Carbon Removal Pathways applicable to Agriculture
Many pathways exist for carbon-dioxide removal. CDR Primer is an excellent resource on breaking down the many different scientific pathways currently being explored for carbon removal.
When most people think of carbon removal, they think of Direct Air Capture projects, where machines are built to suck CO2 out of the atmosphere, and inject it under the ground for long term geologic storage.
Other non-agriclutural pathways include Ocean carbon removal (either through ocean alkalinity enhancement, kelp/biomass sinking, or coastal blue carbon).
In the context of agriculture, the two main pathways being explored are:
In the case of Biochar, the production of biochar itself is seen as a carbon removal pathway that has durability of 100+ years.
In the case of enhanced rock weathering, the natural process that occurs when rainwater falls on crushed basalt (or other silicate) rock over an agricultural field, sequesters carbon and is estimated to have durability of 1000+ years.
Money not making it to farmers
In both cases of biochar and ERW, many of the companies who are producing these credits or managing the projects intend to sell carbon credits to corporates in the private markets, and its unclear to what extent that revenue will make it to the farmer.
In Biochar, the production of biochar for carbon credits is often seen not as financially sustainable business on its own, divorced from the potential to create an actual value-added product. So often biochar production only makes financial sense for a producer if they also plan to sell the physical product of biochar as a soil amendment, or for other uses (e.g. water filtration, waste water treatment, direct application on farm, fertilizer replacement, etc.).
In Enhanced Rock Weathering, the use of basalt or similar rock instead of agricultural lime is seen as a drop in replacement. Since farmers are often paying for application of agricultural lime, many ERW project developers are offering spreading of basalt rock as a no-cost alternative, with the hopes that this is enough financial incentive for the farmer, and the majority (or all) of the revenue from carbon credits sold would go to the project developer, as opposed to land steward or land owner.
Opportunities for self-production
In the biochar context, the best way for farmers to support and fully claim the GHG benefits of using biochar, is to actually engage in production of biochar themselves with their own bio waste feedstock (e.g. through invasive plant removal, or as an alternatives to controlled burns for wildfire prevention).
Self-production is less likely possible in the context of ERW, as this often depends on being physically close or colocated with a mining facility that has sufficient access to the rock material necessary as the agricultural lime replacement.
Registries for MRV & Certifying Credits
Most carbon credits (if being sold in the voluntary markets) need to be certified & independently verified through a Registry, under a specific protocol that dictates rules for project enrollment, and how quantification must happen.
The existing registries in the legacy carbon markets have been mostly focused on forestry credits. These registries include:
- Verra
- Gold Standard
- American Carbon Registry
The above registries have also issued some protocols for durable carbon removal (mostly biochar), but have seen little traction, and most durable carbon removal is getting certified through new registries that are focused on these novel pathways.
Specifically for durable carbon removal, a new set of parties have taken the lead in developing methodologies & verification protocols for the more novel carbon removal pathways. Many of these protocols require significant upfront capital costs, making it prohibitively expensive for small scale farmers to engage in producing and certifying their own credits without some form of investment.
Carbon removal registries & their protocols for agriculturally relevant pathways:
- Isometric (Biochar protocol, Enhanced Rock Weathering protocol)
- Climate Action Reserve (Biochar protocol)
- Puro.earth (Biochar protocol, Enhanced Rock Weathering protocol)
Carbon Market Dynamics
CDR.fyi is a fantastic resource for tracking market trends in the private CDR market. They have leaderboards showcasing the largest suppliers and purchasers in the industry, as well as frequently write blog posts about market trends.
The industry at large is anticipating a lot more government engagement (either through direct procurement, approval of specific registries & protocols for verification, or tax schemes), but as of now most of the market activity and purchases is still in the private sector, led by the high-margin industry of high-tech companies (e.g. Microsoft, Alphabet, Stripe, Meta, etc.).
One interesting trend in the above link worth noting, is that while direct-air capture is to-date the pathway with some of the most pre-purchases and investment, when ranking pathways by actual deliveries (e.g. tons removed to-date), Biochar takes the lead. This is because most of the novel pathways are still at the pilot stage, and expect to scale over the next several years. Whereas biochar is the pathway that is able to demonstrate the most scale as of today.