This is the second in our series on removal-based carbon credits that will run throughout February and March.

Rediscovering an ancient solution

Biochar is more than just a carbon removal solution — it's a combination of ancient practices and modern climate innovation. Biochar is a carbon-rich material created through pyrolysis, a process where organic biomass is heated in the absence of oxygen. People across the world have used biochar-like materials to enrich soil for centuries. 

The most famous example comes from as far back as 2,500 years ago, when indigenous communities in the Amazon basin boosted agricultural productivity by adding charred organic matter to nutrient-poor soils to produce “terra preta,” or black earth.

Similar practices have been found in East Asia, where farmers used charcoal ash to retain moisture and improve crop yields, and in West Africa, where burning and burying organic material helped rejuvenate depleted savanna soils. These age-old techniques are now being rediscovered and modernized, showcasing biochar’s incredible potential as both a soil enhancer and a climate solution.

The science behind biochar: pyrolysis unlocked

When biomass, such as agricultural waste, forestry residues, or other organic materials, is subjected to pyrolysis, a portion of the carbon content is locked into a stable form rather than being released as CO2 or other gases. The result is biochar, a durable carbon sink that can store carbon for over a century — sometimes much longer — making it an excellent option for removing CO2 from the atmosphere with a low risk of reversal.

After undergoing pyrolysis, biomass breaks down into three main products: biochar, bio-oil and syngas. This process turns organic material into a long-term carbon sink while also creating useful byproducts.

Here’s a simple way to represent the process:

Biochar, bio-oil and syngas are the three key products of the pyrolysis process, each with unique benefits and applications: 

• Biochar is a solid, carbon-rich material that stands out for its stability and ability to lock away carbon in the soil for centuries, making it a powerful tool for long-term carbon sequestration.
• Bio-oil is a thick liquid composed of organic compounds. With its potential as a renewable energy source, it represents an innovative way to create sustainable fuel alternatives. It may also be pumped below ground to deliver a durable carbon dioxide removal.
• Syngas is a gaseous mixture of hydrogen (H2), carbon monoxide (CO) and methane (CH4). This versatile byproduct can be used to generate energy or heat, adding to the overall efficiency of the pyrolysis process.

Overcoming the barriers to biochar projects

While biochar offers impressive benefits for both the climate and agriculture, there are still significant challenges to bringing these projects to life.

• Daunting costs: Setting up a biochar facility involves investing in specialized pyrolysis equipment, sourcing feedstock and covering operational expenses. For smaller operators or those in developing regions, these upfront costs can be an obstacle to project development.
• Market uncertainty: While biochar has proven benefits, adoption is still in its early stages in many regions. Farmers, industries and communities may not yet fully understand its potential, making it difficult for stakeholders to predict demand or return on investment. Many countries also lack supportive policies or incentives for biochar projects.
• Technical complexity: The biochar production process demands precise control over pyrolysis conditions and consistent monitoring to ensure the final product meets quality standards. Even applying biochar effectively requires knowledge and training — missteps can lead to poor results. Thus, raising awareness and building capacity among potential biochar users may be necessary.
• Logistical hurdles: Finding adequate biomass feedstock, transporting it to a facility and distributing biochar products can be a significant challenge, especially in remote areas. Plus, feedstock competition from other waste management or carbon removal technologies can sometimes overshadow biochar’s potential.

Carbon credits: the biochar lifeline?

These hurdles point to one potential solution: the role of carbon credits. For some biochar projects, carbon finance isn’t just helpful — it’s essential. Income from carbon credits can offset high startup costs, make up for uncertain market returns and provide the financial flexibility needed to refine processes. For those projects, carbon income has the potential to transform biochar from a promising idea into an impactful climate solution. 

Biochar projects can be an important avenue to achieve real, durable CO2 removal. With their potential to deliver on both permanence and additionality, these projects can yield high-quality credits on the voluntary carbon market. Nonetheless, the greenhouse gas integrity of biochar credits cannot be taken for granted, as several key risks remain on a project level. In our next blog post, we will explain some of these risks and how ratings may vary among individual biochar projects. Follow us on LinkedIn to keep up.