Biochar has emerged as a powerful waste-to-carbon technology. Produced through pyrolysis by heating biomass in low-oxygen environments, biochar - unlike charcoal made for combustion- transforms organic waste into a stable form of carbon with multiple environmental co-benefits. In the context of waste management, it offers a unique value proposition: divert waste, sequester carbon, and regenerate soils. However, its effective integration into carbon markets and waste systems requires rigorous standards, life-cycle accountability, and clarity around production scale and quality.
Biochar as a waste management solution
Biochar production is fundamentally a waste valorization process. It repurposes organic residues that would otherwise be incinerated, landfilled, or left to decompose. Feedstocks can include these various properties:
- Agricultural residues (e.g. rice husks, nut shells, corn stalks)
- Forestry waste (e.g. sawdust, tree bark)
- Urban biomass (e.g. paper mill sludge, yard plant trimmings)
- Animal manure
Not all biochar projects are created equal. To ensure their environmental integrity and permanence, rigorous standards and methodologies are increasingly required by carbon markets and project investors.
For more on why you should include waste management projects in your portfolio, please read our article.
Standards and methodologies
In the carbon credit landscape, biochar projects must meet high thresholds of accountability. Leading methodologies such as those from Puro.earth, VCS-Verra, the European Biochar Certificate (EBC), the World Biochar Certificate (WBC), and Methodology Biochar Rainbow - RIV-BICRS-GEN V1.0 outline requirements in three key areas:
1. Feedstock sustainability
Methodologies assess whether the biomass meets the following criteria:
- It is a true waste with no higher-value alternative use
- It does not contribute to deforestation or impact high conservation value lands
- It is harvested with full traceability and in a way that supports local sustainability
2. Life-Cycle Assessment (LCA)
To ensure that a biochar project genuinely reduces emissions and doesn’t overestimate its climate benefits, it must conduct a Life-Cycle Assessment (LCA). This means accounting for all greenhouse gas emissions generated throughout the project’s life, not just those captured in the biochar itself.
A robust LCA should include the following features:
- Complies with ISO 14040/44 standards: These are internationally recognized guidelines that ensure the LCA is carried out with scientific rigor and transparency. Following these standards means that the results are consistent, comparable, and credible.
- Follows a "cradle-to-grave" approach: This means the LCA must assess emissions at every stage of the project, including:
- Inputs: Emissions from harvesting, collecting, and transporting the biomass feedstock.
- Production: Emissions from the pyrolysis process, including energy use and any byproducts like methane or syngas.
- Output & Use: Emissions from storing, handling, transporting, and applying the biochar.
- End-of-life: Any emissions or decay from how the biochar is used over time (e.g. in soil or materials).
- Third-party verified: To ensure impartiality and accuracy, the LCA should be reviewed and validated by an independent auditor. This helps prevent inflated carbon credit claims and builds trust with buyers and regulators.
A strong LCA is the backbone of a high-integrity biochar project. It ensures that only real, measurable, and additional carbon removals are credited, reinforcing biochar’s role as a trustworthy solution in both waste management and climate action.
3. Stability & permanence
The long-term climate impact of a biochar project depends on how stable the carbon in the biochar is once it's applied—whether to soil, construction materials, or other systems. This carbon permanence is assessed through laboratory analysis of the biochar’s chemical composition, not the soil it’s applied to.
Two key elemental ratios are used as proxies for biochar stability:
- H/C ratio (Hydrogen-to-Carbon): Indicates the degree of carbonization. A ratio ≤ 0.4 means the biochar has undergone sufficient pyrolysis and is more resistant to microbial breakdown, suggesting high permanence.
- O/C ratio (Oxygen-to-Carbon): Reflects the oxygen content and chemical reactivity. A ratio ≤ 0.2 is ideal, indicating a chemically stable and less degradable material.
These values, combined with production conditions, especially pyrolysis temperatures above 550°C, help determine whether the biochar is suitable for long-term carbon sequestration. When biochar meets these thresholds, it can be considered a highly durable carbon sink, with some carbon remaining stable in the environment for over 1,000 years.
Artisanal vs industrial biochar
The biochar sector spans from artisanal village kilns to industrial-scale pyrolysis plants, each with unique implications for waste management and carbon markets.
Artisanal production
Small-scale biochar operations are often community-led, using simple kilns to convert agricultural or forestry residues into char. These projects:
- Address localized waste problems
- Offer low-cost and low-barrier entry for rural communities
- Can be highly impactful when integrated with sustainable agriculture or cooking systems
However, they often face challenges such as:
- Inconsistent quality control
- Lack of emissions monitoring
- Difficulty meeting certification standards without technical support
Industrial production
On the other end of the spectrum, industrial pyrolysis facilities process large volumes of biomass using high-tech reactors. These projects:
- Produce high-quality, standardized biochar
- Generate co-products like bio-oil and renewable heat
- Are more easily audited for LCA, lab testing, and financial additionality
But industrial projects can struggle with:
- Feedstock sourcing sustainability at scale
- Market leakage, if feedstock is diverted from other climate-friendly uses
- Community engagement and benefit-sharing, especially if disconnected from local needs
Both models have value, artisanal for decentralization and social co-benefits, industrial for carbon scalability and investment readiness. Ideally, both are supported under evolving methodologies that adjust requirements based on project scale and context.
For an example of a waste management project, please check out our blog on the circular economy.
Additionality and carbon market viability
For biochar to be recognized as a credible carbon removal solution in the Voluntary Carbon Market (VCM), it must meet strict standards of additionality, a core requirement that ensures the climate benefit wouldn't have occurred without the project. In other words, a project should only earn carbon credits if it enables outcomes that are beyond business as usual.
Additionality is especially important in biochar projects because the technology can generate co-products and revenue streams beyond carbon credits. To maintain integrity in carbon markets, it's critical to evaluate whether these projects truly depend on carbon finance, and whether they deliver measurable climate mitigation in addition to other environmental and social benefits.
There are three types of additionality that high-quality biochar projects must demonstrate:
- Environmental additionality: Proving the biomass would have emitted CO₂ if not charred (e.g. through decomposition or open burning)
- Financial additionality: Showing that carbon credits are essential to project viability
- Regulatory additionality: Confirming there are no laws mandating the project’s activity
Projects that meet these criteria and disclose financial models, especially where carbon finance is the only enabling income stream, score high on quality assessments.
Social and environmental co-benefits
Biochar doesn’t just manage waste or sequester carbon, it can enhance social equity, soil health, and rural livelihoods.
- Improves soil fertility and reduces input costs for farmers
- Can create jobs in biomass collection, transport, and application
- Offers training in sustainable practices
- Reduces GHG emissions from fertilizers, waste disposal, and water pollution
It contributes directly or indirectly to 13+ Sustainable Development Goals (SDGs), including SDG 2 (Zero Hunger), SDG 6 (Clean Water), and SDG 13 (Climate Action). For an example of a waste management project, please check out our blog on the circular economy.
Biochar represents a practical, permanent, and versatile climate solution. It takes what would otherwise be a liability, organic waste, and turns it into an asset. Leading to long-lived carbon sinks, healthier soils, cleaner water, and new livelihoods.
The key to scaling responsibly lies in methodological rigor, clear standards, and inclusive models. Ones that support both village-level kilns and industrial hubs, while always prioritizing climate, community, and circularity.
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