Biochar Carbon Credits: How Biochar Carbon Removal Works

Biochar locks carbon that plants pulled out of the air into a form that breaks down very slowly. When that biochar ends up somewhere it stays - in soil, in concrete, in a reclaimed mine site - the carbon is removed from the atmosphere for centuries. That removal can be measured, certified and sold as a carbon removal credit, and for many producers the credit is worth as much as the biochar itself.

Biochar is also the carbon removal method that actually delivers. According to market tracker CDR.fyi, biochar accounted for 86% of all durable carbon removal credits delivered worldwide between 2022 and mid-2025 (CDR.fyi, September 2025). This guide is written for producers and sellers: what has to be true for your biochar to earn credits, which methodologies certify it, what the credits sell for, and where to sell them.

What a biochar carbon removal credit is

One carbon removal credit stands for one tonne of CO₂ taken out of the atmosphere and stored durably. For biochar, the number of credits a batch earns is roughly:

• the carbon in the biochar, converted to CO₂ (1 kg of carbon = 3.67 kg of CO₂),
• minus the share expected to break down over the durability period (the persistence discount),
• minus the emissions from collecting the biomass, running the pyrolysis process, and transporting and applying the biochar.

Depending on carbon content and how far the biochar travels, a tonne of well-made biochar typically yields around 2 to 2.5 credits. The exact figure is calculated batch by batch under your carbon methodology.

If you are new to biochar

A credit is not attached to the biochar you sell. It is a separate certificate that lives in a registry. You can sell the biochar to a farmer and the credit to a company - two products from one batch - as long as only one party ever claims the removal.

Artisan or industrial - two ways to make creditable biochar

Biochar carbon removal comes from two very different kinds of producers, and the carbon methodologies treat them differently.

• Artisan (distributed) production uses simple technology: open flame-curtain kilns such as the Kon-Tiki, soil pits or small batch kilns, run by trained farmers or local cooperatives close to where the biomass grows. Investment is low and the biochar usually goes straight back into local soils. Because there is no flue-gas treatment, each batch produces more methane and particulate emissions, quality varies more from batch to batch, and credits depend on careful operator training and batch-level records. To support the biochar mission where it does the most good, artisan certification is generally limited to low- and middle-income countries. CSI's Global Artisan C-Sink, for example, only covers countries classified by the World Bank as low-income, lower-middle-income or upper-middle-income, which pushes producers in high-income countries towards industrial pyrolysis.
• Industrial production covers continuous or large batch pyrolysis plants with varying levels of technology - from compact containerised units to large multi-tonne-per-hour plants. What they have in common is controlled process conditions: monitored temperatures and residence times, combustion or after-burning of the pyrolysis gases, often heat recovery, and stronger emission control. The result is more consistent biochar quality, larger volumes and lower process emissions per credit.

	Artisan / distributed	Industrial
Technology	Flame-curtain kilns (e.g. Kon-Tiki), pits, small batch kilns	Continuous or large batch pyrolysis plants
Emission control	Limited - relies on good operating practice	Gas combustion, monitoring, often heat recovery
Quality consistency	Varies by batch and operator	Consistent, process-controlled
Where it is certified	Generally low- and middle-income countries	Worldwide
Typical methodologies	CSI Global Artisan C-Sink, Isometric distributed production module	CSI Global Biochar C-Sink, Puro.earth, Isometric, Verra VM0044

Removal versus avoidance - why it matters where your biochar goes

On BiocharLink, each use case carries a chip: Carbon Removal Compatible or Carbon Avoidance Compatible. The difference decides whether a credit is possible at all.

• Carbon removal means the carbon stays stored. Biochar mixed into soil, cast into concrete or asphalt, used to reclaim mine land, or fed to livestock and returned to the soil through manure keeps most of its carbon for a century or more. These end uses can earn removal credits.
• Carbon avoidance means the biochar replaces a fossil fuel and is then burned. Bio-coal used as a reductant or fuel in steelmaking (met-coal) releases its carbon in the furnace. The climate benefit is real - fossil coal stays in the ground - but nothing is stored, so it cannot be sold as a removal. Avoidance is usually counted inside the steelmaker's own emissions reporting, for example under CBAM and the EU ETS, rather than as a removal credit.

End use on BiocharLink	Carbon outcome	Removal credit possible?
Agriculture and soil amendment	Stored in soil	Yes
Construction (concrete, asphalt, mortar)	Locked in the material	Yes
Mine reclamation and soil remediation	Stored in soil	Yes
Animal feed and bedding	Passes into manure and then soil	Yes, under rules that track it to the soil
Met-coal for steel	Burned in the furnace	No - avoidance only
Activated carbon	Often regenerated or incinerated	Usually not

Every methodology keeps a list of accepted end uses, and the lists differ. Check that your buyer's application is on your methodology's list before you promise credits.

Quality certification and carbon methodology are two different things

This is the point most new sellers mix up.

• A quality certification says what the biochar is: that it is made from approved feedstock, meets limits for contaminants such as heavy metals and PAHs, and is safe for a given use. The best-known schemes are the European Biochar Certificate (EBC) and the World Biochar Certificate (WBC), both run by Carbon Standards International (CSI). A quality certificate on its own earns no carbon credits. Many buyers in agriculture and construction ask for one, but plenty of producers - especially artisan producers and those selling into markets that do not require it - sell biochar without any quality certification at all.
• A carbon methodology says how much carbon was removed: it sets the rules for measuring, deducting emissions, tracking the biochar to its end use and verifying the result, and the registry then issues credits. A carbon methodology is what you need to sell credits.

The two can overlap. CSI's Global Biochar C-Sink builds on EBC or WBC certification of the production site, so on that route you get both from the same body. Other methodologies, such as Puro.earth and Isometric, set their own sampling and lab-testing requirements inside the methodology and do not need a separate quality certificate - so producers on those routes usually skip EBC or WBC unless their biochar buyers ask for it or it opens a market for them. What a full lab report contains, and what the quality limits are, is covered in our guide to biochar specifications. Whichever route you choose, register each tonne under one methodology only - crediting the same tonne twice is double counting, and buyers check for it.

How durability is measured

Not all of the carbon in biochar is equally stable. Most of it sits in condensed aromatic rings that soil microbes can barely touch. A smaller share is more reactive and breaks down within decades. Methodologies therefore credit only the part expected to remain after a set period.

• H/Corg ratio. The molar ratio of hydrogen to organic carbon is the standard lab proxy for stability: the lower the ratio, the more condensed the carbon. Biochar generally has to stay below 0.7, and the strictest durability tiers ask for below 0.4.
• 100-year and longer claims. Most credits are calculated on a 100-year horizon. Puro.earth's 2025 methodology added a 200+ year label (CORC200+) for biochar that qualifies.
• 1,000-year claims. Isometric certifies 1,000-year durability using random reflectance - a microscopy method borrowed from coal science that measures how much of the biochar behaves like inertinite, a carbon form that is stable over geological time. The method is newer and some researchers still debate how conservative it is in soil, so expect buyers to ask about it.

If you are new to biochar

Pyrolysis temperature drives stability. Biochar made at higher temperatures (roughly 550 °C and above) usually has a lower H/Corg ratio and earns more credits per tonne. A lab report showing H/Corg, organic carbon and ash for each production batch is the first document any credit buyer will ask for.

The carbon methodologies

A standard body runs the rules and the registry; the methodology (or protocol) is the specific rulebook a project is certified under. Some bodies run more than one.

Standard body	Methodology	Scale	Credit	Durability basis
Carbon Standards International (CSI)	Global Biochar C-Sink	Industrial	C-sink certificate	Persistence model per end use; builds on EBC/WBC certification
Carbon Standards International (CSI)	Global Artisan C-Sink	Artisan, low- and middle-income countries only	C-sink certificate	Flame-curtain production by trained operators
Puro.earth	Biochar Methodology (Edition 2025)	Industrial	CORC	100 years, with a 200+ year label
Isometric	Biochar Protocol, with production and storage modules (including a distributed-production module)	Industrial and distributed	Isometric Certified Removal	Up to 1,000 years, using random reflectance
Verra	VM0044 (v1.2, active since June 2025; v2.0 in revision)	Industrial	VCU	Set by the methodology

Digital MRV - why it is essential

Every credit rests on MRV: monitoring, reporting and verification. Someone has to prove which biomass went in, how each batch was pyrolysed, how much biochar came out, where every tonne went and that it was actually applied. Done on paper and spreadsheets, that evidence is slow to audit, easy to get wrong and hard for a buyer to trust - and most failed verifications trace back to gaps in exactly these records.

Digital MRV (dMRV) captures the data at the source - sensor readings from the plant, geotagged photos, digital delivery notes signed by the end user - and keeps it in one tamper-evident chain from biomass intake to the final carbon sink. It cuts the time from production to issued credits, makes audits cheaper, and gives buyers the transparency that now decides which credits sell. With buyers and methodologies tightening their evidence requirements every year, dMRV is no longer optional for a serious project.

One example is Sarva Carbon by PyroCCS, a dMRV and workflow platform for industrial biochar projects. It is approved by CSI under the EBC/WBC guidelines and compatible with Puro.earth and Isometric. Each biochar delivery carries a QR code that the customer scans to confirm receipt, record the sink type and GPS location, and sign off the transfer - creating an auditable record from production to permanent storage.

What credits sell for, and who buys them

• Price. The Nasdaq/Puro.earth biochar index (CORCCHAR) averaged $125-145 per tonne through 2025, and CDR.fyi's weighted average for biochar sat at roughly $136 per tonne in 2026. Individual deals range more widely, from about $100 to $250, depending on durability claim, artisan or industrial origin, co-benefits, volume and the buyer's requirements.
• Buyers. Demand is concentrated. Microsoft alone accounts for 46% of all biochar removal tonnes contracted to date, and together with Google, BCG and JPMorgan the top four buyers hold 57% (CDR.fyi, 2025). Swiss Re, SEB and Nasdaq are among the companies that buy almost only biochar.
• Deal size. Most transactions are small: more than half of delivered tonnes come from orders under 100 tonnes. A small producer can sell, but usually through a marketplace or broker rather than direct to a hyperscaler.

If you are new to biochar

Do not plan your business on the credit price alone. Credits are paid on delivery of verified tonnes, verification adds months, and a single large buyer can move the market. The producers who do best treat credits as a second revenue line on top of a biochar product that already sells.

Where to sell biochar credits

Once your credits are issued, most producers sell them through carbon removal marketplaces and procurement platforms, which bundle credits from many projects for corporate buyers. Each runs its own due diligence before listing a project, so expect to share your methodology documents, verification reports and MRV data.

• Patch - a platform and API that companies use to buy carbon credits, including embedding removal purchases in their own products.
• CEEZER - a procurement platform helping companies build and buy carbon credit portfolios.
• Klimate - a carbon removal platform that builds removal portfolios for companies.
• Supercritical - a marketplace focused on permanent carbon removal.
• Senken - a carbon credit marketplace with its own project due diligence.
• CNaught - a provider of curated carbon credit portfolios for businesses.

Larger producers also sign offtake agreements - multi-year forward contracts - directly with big buyers, usually once they have a verified track record.

What you need before a buyer will sign

1. A carbon methodology. A registered project under one methodology that fits your scale (artisan or industrial) and your end uses.
2. Sustainable feedstock records. Proof the biomass is a residue or sustainably sourced, and EUDR documentation where it applies.
3. Lab data per batch. Organic carbon, H/Corg, ash and contaminants, as your methodology requires.
4. A life-cycle assessment. Emissions from feedstock, production, transport and application, built to your methodology's template.
5. End-use tracking. Records showing where each tonne went and that it was applied - ideally captured digitally through dMRV.
6. Independent verification. A validation and verification body that checks your data before credits are issued.
7. A registry account. Credits are issued, transferred and retired there. The retirement record is what your buyer reports.
8. Quality certification, if your biochar buyers need it. EBC or WBC is often expected in agriculture and construction, and it is required on the CSI Global Biochar C-Sink route.

Common pitfalls

• Treating a quality certificate as a credit. EBC or WBC proves the biochar is fit for use; it does not make it a carbon credit.
• Selling the same tonne twice. If your biochar customer also claims the removal in their own reporting, you cannot sell a credit for it. Put the credit rights in writing in every sale contract.
• Losing the end-use trail. Biochar sold to a trader who resells it without application records usually cannot be credited.
• Mixing removal and avoidance. Credits for biochar that went into a furnace will not survive an audit.
• Overstating durability. Buyers increasingly ask which time horizon and test method sit behind a claim. Be precise: "100-year, H/Corg 0.3" is worth more to them than "permanent".

Questions a credit buyer will ask

1. Which methodology certifies your credits, and is the project registered or only in validation?
2. Is the production artisan or industrial, and where is it located?
3. What durability horizon do your credits claim, and on which test (H/Corg, random reflectance)?
4. What is the end use, and how do you track each tonne to it?
5. How is your MRV data captured - digitally at the source, or compiled afterwards?
6. What are your process emissions per tonne of biochar, and who reviewed the LCA?
7. How many credits have been issued and delivered so far, and to whom?
8. How do you prevent double counting with your biochar customers?

Next steps

BiocharLink connects biochar producers with buyers for both the material and its applications. If your biochar goes into soil, construction, mine reclamation or animal feed, it is carbon removal compatible - list it, and buyers who need certified removal can find you.

List your biochar on BiocharLink

Looking at the buyer's side? Our buying guides explain what each application needs from the biochar itself. Questions about methodologies or credit sales? Reach out via our contact form.

Market figures as of October 2026. Sources: CDR.fyi, "Biochar Carbon Removal Market Snapshot 2025" (September 2025); Nasdaq/Puro.earth CORCCHAR index; Puro.earth Biochar Methodology, Edition 2025; Isometric Biochar Protocol; Carbon Standards International, Global Biochar C-Sink and Global Artisan C-Sink guidelines; Verra VM0044.