It is evident that biochar is no longer a niche topic. Though at first sight, it may resemble a familiar fossil fuel, this coal-like material has proved to hold enormous potential as a key technology piece in the battle against the climate crisis.

Interest in biochar carbon removal (BCR) got a boost in October 2018, when the IPCC classified it as a promising “negative emission technology”. Over the past years, BCR has been receiving increased attention, in part because it does not suffer from some of the drawbacks that affect other carbon dioxide removal (CDR) solutions, such as low technological maturity or uncertainty of cost-effectiveness. 

This article examines why BCR seems to have been elevated recently and discusses the emergence of BCR as one of the main durable CDR methods available for delivery today. In addition, it will examine the body of research on its permanence, outline the available third-party standards and methodologies, and highlight some developers of high-quality BCR projects that CEEZER works with. 

What is biochar, and what is it used for?

Biochar is made by heating biomass in an oxygen-limited environment through a process called pyrolysis. The biomass, which has removed CO₂ from the atmosphere during plant growth, is broken down into a carbon-rich material that is then compressed into a solid form. In Germany, biochar is therefore also aptly referred to as “Pflanzenkohle” – meaning plant coal. Without turning it into biochar, the photosynthesis capacity of plants would be wasted from a carbon perspective. Plants absorb CO₂, and without converting the biomass into biochar, the CO₂ would be released back into the atmosphere due to biomass decay or uncontrolled combustion. This process thus locks the CO₂ into the char, making it an effective means of carbon sequestration.

After production, biochar is typically used as a soil amendment, which is the focus of the majority of CDR projects. However, there is a seemingly ever-growing range of other applications for biochar, which all have varying levels of durability. For example, biochar can be stored in long-lasting products or buried deep underground. Other possibilities include its use in wastewater treatment and as an additive for construction, plastics, paper, and textiles. Regardless of the application, it is important to consider that the durability of the carbon depends on the lifetime of the product, or the period the storage is left intact.

The term "biochar" is commonly used, but only refers to one product and not the removal process or the other two products of pyrolysis (i.e. bio-oil and syngas). Furthermore, not all biochar that is produced effectively and permanently removes carbon from the atmosphere – it depends largely on the application.

To address these limitations, the European Biochar Industry Consortium (EBI) recently consulted numerous experts in the biochar industry and settled on a new term: “Biochar Carbon Removal” (BCR). Thus, BCR is used to refer to the process of durable carbon removal. The output of BCR includes biochar, as well as heat and electricity.

Solid science shows that carbon stored in biochar is … pretty solid

Biochar has been extensively researched, accounting for almost 40% of the coverage on CDR methods in approximately 28,000 scientific publications on the topic to date (The State of Carbon Dioxide Removal, 2023). Research on biochar is growing faster than on any other CDR method, representing about 50% of all CDR-related studies published in 2021. Interestingly enough, Henrietta Moon (CEO of Carbo Culture) recently stated in an OpenAir webinar that the science of biochar is so well-established that one can no longer receive a Ph.D. on the topic.

It has been long known that carbon captured in biochar can be stored temporarily, for a very long time. How long exactly remains a topic of discussion, however. Once tilled into soils, the carbon slowly decays over centuries or millennia until almost all of it is gone. How much and for how long precisely it is stored depends on various factors, such as the type of biomass feedstock, pyrolysis conditions, and soil characteristics (Woolf et al., 2021; Tisserant & Cherubini, 2019; Wang et al., 2016).

New research by Hans-Peter Schmidt and colleagues, featured on a website called the Biochar Journal, suggests that biochar may be able to store carbon for longer periods than previously believed. It argues that the stable fraction of biochar, accounting for 75% of its carbon content, will persist after soil application for more than 1,000 years, regardless of soil type and climate. The claims made by this study – which has not been peer-reviewed – have been reproduced across the market since. However, it is yet to be evaluated by other experts, and the conclusions should be taken with a grain of salt.

The science of biochar permanence is still evolving, and the market is awaiting a firmer scientific consensus. Nevertheless, based on the existing body of research, BCR credits can be considered to have a permanence in the range of 100-1,000 years (Woolf et al., 2021; IPCC, 2019). Therefore, CEEZER classifies it as "carbon removal with long-lived storage" (Oxford Category 5).

The icing on the cake is that biochar offers many well-documented benefits beyond just storing carbon. For instance, Schmidt et al. (2021) conducted a review of 26 meta-analyses published since 2016 and concluded that all provide compelling evidence for the beneficial effect of biochar on the agronomic parameters investigated. These include positive effects on yield, root biomass, water use efficiency, microbial activity, and soil organic carbon.

BCR was the main durable CDR method with actual deliveries in 2022

Although the widespread deployment of BCR still faces various barriers, the technological readiness of biochar as a soil additive is relatively high compared to other CDR methods (Möllersten, 2022). Biochar has been around for decades, and its production technology is already developed and ready to scale. In fact, the technique of using charcoal to improve the fertility of soils originated in the Amazon basin many thousands of years ago. In contrast, many other CDR technologies are still validating their approach and are attempting to reduce costs before scaling.

This also explains why the majority of durable CDR credits (i.e., those that sequester carbon for 100 years or longer) that have actually been validated and issued thus far have been from BCR projects. According to CDR.fyi, nearly all the roughly 65,000 tCO₂e that have been removed from the atmosphere in 2022 have been sequestered using this method. Currently, the CDR market is primarily dominated by pre-purchases and offtake agreements. However, BCR, along with bio-oil and enhanced rock weathering, represents an exception to this. Credits from these projects are one of the few CDR credits that companies can purchase and retire in the short term on an ex-post basis, instead of waiting for delivery many years into the future. According to CDR.fyi data, BCR orders are typically fulfilled within about five months of purchase, which is significantly faster than other methods that take an average of 30–58 months.

Timothée Dulac from GECA Environnement supports the view that the market is maturing: “Over the past few years, we have seen significant growth and development in the biochar carbon credit market. More and more companies recognize the value of this technology as a way to reduce emissions and improve soil health”, he says. “We believe this trend will continue in the years to come, and we are committed to playing a leading role in advancing the biochar industry towards removing more CO₂ from the atmosphere.”

Most BCR carbon credit sales in 2022 came from larger projects in North America, such as those from Wakefield Biochar, Douglas Country Forest Product, Freres Biochar, and Oregon Biochar Solutions. As of 2023, it is estimated that there are about 170 biochar producers in the USA, and that number is expected to reach 200 before the end of the year.

Yet, biochar production on the other side of the Atlantic is also growing strongly and will continue to mature. The European Biochar Market Report 2022–2023 notes that the number of biochar production plants in Europe is expected to grow from 130 installations at the end of 2022 to 180 by the end of 2023. The report predicts that over 50,000 tons of biochar, equivalent to up to 150,000 tCO2e, will be produced in 2023. 

Importance of robust methodologies and third-party certification of BCR projects

Of course, BCR is not a panacea. It has its own unique set of challenges and risks, and each project needs to be assessed on its own merits. Potential issues can be the lack of financial additionality, unsustainable feedstock origin, methane emissions that are not accounted for, or the lack of a proper life-cycle assessment. Additionally, the application of the biochar in question is important to look at, especially as this is closely related to its permanence and potential co-benefits.

Strict MRV, methodologies, registries, and third-party verification are vital to ensure the effectiveness and quality of CDR efforts. In order to be listed, CEEZER requires project developers to work with third-party standards. Below, we highlight three key standards for BCR, each of which differs slightly in their coverage, calculations, and monitoring solutions.

In 2019, our partner Puro.earth introduced the very first CDR crediting methodology for BCR to the market. The methodology was updated in 2022 to reflect scientific advances and incorporate feedback from biochar producers, buyers, and auditors. The updated methodology now enables the certification of more biomass sources and different technology types. In August 2022, Verra released the Methodology for Biochar Utilization in Soil and Non-Soil Applications (VM0044), which covers the use of biochar in agricultural soils, as well as some applications such as biochar-amended concrete and building materials.

Another major voluntary standard is the European Biochar Certificate (EBC), which has already been utilized by 100 certified businesses to produce biochar. Since 2020, carbon sinks created by the industrial production of biochar and its subsequent application in agriculture or durable materials can be certified according to the EBC C-sink standard to create tradable climate service tokens. Last year, Carbon Standards International (CSI), became the responsible organization for all operations related to the EBC and now hosts its respective CDR accounting methodology.

On top of that, Climate Action Reserve is also developing the U.S. and Canada Biochar Protocol, which will provide guidance to biochar projects in North America.

Some companies opt to create their own carbon credit standards instead of using existing ones. One such example is BELOW2, whose VCI-S-1000 methodology for BCR projects is partially based on guidelines from the EBC and generally follows the principles outlined in the ISO 14060 family of documents. They argue that “existing certification standards, especially in the area of CO₂ removals, are not sufficiently thorough in addressing data parameters beyond biochar production which have an important influence on the permanence and CO₂ storage capacity of the project.” To address the issue of not tracking the application of biochar, BELOW2 employs a holistic approach to ensure data collection in all value chain stages. For this, they use blockchain to create a fully transparent, traceable, and immutable registry for accounting and documenting carbon credits.

Our partners at Carbonfuture provide an end-to-end digital platform, spanning the supply, tracking, and trading of high-value carbon removal credits based on advanced CDR technologies, such as BCR. Carbonfuture’s tracking system solves carbon credit uncertainty by utilizing third-party methodologies, auditing, and certification as well as full digital traceability from physical removal to retired credit. The system currently supports projects using the CSI and Verra methodology for BCR but is designed to scale across a wide range of CDR technologies and standards as they become available.

The emergence of small-scale biochar projects in the global South

Up until mid-2022, the standards for BCR focused on advanced pyrolysis plants in developed countries. This missed the opportunity to incentivize local and decentralized production of biochar, in which the biomass owner itself benefits from the characteristics of biochar in their soils. By integrating biochar into farming practices, smallholder farmers can contribute to carbon removal while also improving soil health and crop productivity. Low-cost equipment, such as Kon-Tiki-type kilns, can democratize access to the benefits of biochar, even in areas where high-tech production facilities are not available (Schmidt & Taylor, 2014). 

One of the main barriers to the widespread adoption of biochar is the lack of awareness and understanding of the technology among farmers, investors, and policymakers. Many farmers are still unaware of the benefits of biochar and how to use it effectively in their fields. Household-level systems face similar adoption barriers as improved cookstoves, such as attention requirements and sociocultural fit. 

Fortunately, recent standards have now opened the door to support more small-scale biochar projects in rural or less developed regions. The new Verra methodology distinguishes between low- and high-technology production facilities to accommodate small-scale biochar projects. To assist decentralized biochar production, CSI recently introduced a separate standard for smallholder farmers: the Global Artisan C-Sink Standard. This covers the production, processing, and application of biochar by smallholder farmers, focusing on rural, family-orientated farmers, working on plots of land that are no more than a few hectares. The standard allows for third-party certification of biochar made in an artisanal way, such as with Kon-Tiki type pyrolysis.

Mart de Bruijn, a co-founder of Dutch Carboneers, initiated a project under the new standard across 500 villages in Odisha, a province in mid-east India. “A decentralized biochar project is an effective way to do carbon removal, improve climate adaptivity and create more robust soil ecosystems in one go”, he says. “During our visit to India, we were moved by the motivation and impact on the smallholder farmers.”

Developing biochar systems remains a challenging task due to their complexity and long lead times. Several barriers to deployment, such as limited practical know-how and capital constraints, are especially pronounced in developing countries, where the potential for biochar systems to improve soil fertility as a soil amendment is greatest (Fridahl et al., 2021; Möllersten, 2022).

Another example of a pioneering company using the Artisan C-Sink standard is Terra Preta, who is working with Latin American farmers. "Networks of small-scale biochar production sites in the Global South have tremendous potential to remove vast amounts of carbon while boosting income and resilience of rural communities in those regions that are often the most vulnerable to climate change,” says Lorenz Buser, co-founder of Terra Preta. “The Artisan C Sink standard by Carbon Standards International is crucial to ensure the integrity and facilitate trust between carbon removal buyers and organizations focusing on this type of project.”

The role of policy 

As of today, the primary market for carbon removal is the voluntary carbon market (VCM). Although this market is undergoing significant growth, it is still small compared to compliance markets such as the European Emissions Trading Scheme (ETS). In the future – not earlier than 2030 – we could see an inclusion of carbon removal in the ETS, potentially paving the way for inclusion in other compliance markets and marking a step change in the demand for CDR, including BCR.

The biggest challenge in including CDR and BCR in compliance with climate policy today is that there is no clear definition of what high-quality carbon removal actually means, and how to certify it. This is precisely what the European Carbon Removal Certification Framework (CRCF) is trying to address. It includes a section on “permanent removals,” defined as methods with the durability of at least several centuries. Many stakeholders are making a case for the inclusion of BCR in this permanent category. Progress is expected in Q3 of 2023, with decisions to be taken in 2024.

“We are on track to having BCR recognized and certified as a permanent carbon removal technology in European policy, which would be a huge step in scaling BCR to climate relevance”, says Sebastian Manhart, who is Senior Policy Advisor at Carbonfuture and Lead of the Policy Group at EBI. 

The direction of the CRCF is likely going to have immediate impacts on the VCM, seen by many as an early indication of where CDR is heading and followed closely by companies that are currently opting to voluntarily procure CDR, but which might soon be legally obliged to do so. 

In the USA, significant investments have been made to scale up the CDR industry, particularly through the Infrastructure Investment and Jobs Act (IIJA) and the Inflation Reduction Act (IRA). These landmark policies have invested hundreds of billions of dollars into the green transition, including significant funding for CDR through the 45Q tax credits and the DAC Hubs program.

However, the focus has been almost exclusively on Direct Air Capture (DAC), with BCR and biomass-based removals being less well-known and promoted. The Farm Bill, due in 2023, holds a lot of promise for BCR and has enormous potential. In particular, the Biochar Research Network Act – which foresees an investment of $50 million per year for five years into the intersection of biochar and agriculture – looks likely to be incorporated into and passed through the Farm Bill.

What to consider when buying biochar carbon credits

Seeing the various third-party certified methodologies that are already available, it can be argued that biochar has a mature MRV readiness compared to many other carbon removal methods. Yet, as this segment continues to scale, buyers must be aware of project-level risks associated with this emergent credit type. 

Organizations interested in purchasing carbon credits should first check if the biochar is applied in a way that ensures stable sequestration, such as through direct soil applications. In addition, the origin of the feedstock is a key aspect. The biomass used to create biochar needs to be sustainable. Broadly speaking, this means that the specific biomass should not have been grown solely for the purpose of creating biochar. Rather, high-quality projects use agricultural and food processing residues, or other waste materials such as thinning wood and shavings. On top of that, it is important to keep in mind that as this industry matures, the risk of non-additionality increases. Other revenue streams, such as the sale of biochar as a soil amendment or heat, may become sufficient to support the project.

As more projects enter the market, it will be interesting to compare the different approaches taken by each developer, and how this influences the cost structure. Differences in the project location, scale, biomass type, equipment, and co-benefits will ultimately result in widely varying price levels. CEEZER’s experience in this emerging market already confirms this variety: carbon credits from BCR projects can cost everything from $60 – 500 per tCO₂e. 

CEEZER is paving new paths in the VCM to facilitate direct trade between project developers and ambitious organizations that want to take climate action. Our focus is on improving visibility and market access for CDR players, including biochar project developers such as Dutch Carboneers, Terra Preta, and Novocarbo. 

This is also exemplified by the partnership with GECA Environnement, a Canadian organization that supports BCR projects of various sizes by providing technical expertise, project management skills, and access to its network. “Our collaboration with CEEZER has been essential in helping us expand our impact in the biochar market. Through our partnership, we have been able to access new markets and connect with a wider range of stakeholders, including carbon credit buyers.”, Timothée Dulac states. “This is especially true for the European buyer market where we have gained increased exposure through CEEZER's marketplace.”

If you are interested in partnering with CEEZER as a project developer or learning more about BCR and purchasing carbon credits from these projects as a buyer, please get in touch or book a demo today.