Biochar is carbon removal's jack of all trades. Here's why

Addressing the climate emergency demands reduced greenhouse gas emissions and effective Carbon Dioxide Removal (CDR) solutions to reverse harm already done.

Only carbon removal can balance hard-to-abate emissions and get us to the required net-zero emissions scenario. One CDR technology is leading the way: Biochar Carbon Removal (BCR), an innovation with game-changing potential. From its carbon removal capabilities to the vast array of co-benefits it offers, BCR is set to become an essential part of any carbon removal portfolio.

BCR is a science-backed approach to carbon removal and its magic lies in pyrolysis: using high heat in a limited oxygen environment to transform biomass into biochar.

Through photosynthesis, biomass accumulates carbon, which via pyrolysis (heating without oxygen) becomes biochar — a highly porous, stable and durable form of carbon that can effectively store CO2 for extended periods and provide a wide range of co-benefits.

For net-zero targets, BCR isn't optional — it's crucial. It can handle between 0.44–2.62 Gt CO2 removal yearly, covering up to 35% of CDR needs in climate stabilization scenarios. BCR can already be deployed on a large scale and is certifiable, traceable, and verifiable under third-party standards. As of 2022, BCR accounted for 87% of total CDR deliveries (52kt delivered) at a substantially lower cost than all other durable CDR approaches. On average, $179/t CO2 for BCR compared to an average price of $388/t across all CDR approaches. The credit rating platform BeZero recently further confirmed confidence in BCR, issuing an A rating to a BCR project, its first appraisal of CDR credits.

Biochar is a stable form of highly concentrated carbon and the durability of BCR hinges on the quality of the biochar used and its end use. Unless through burning, which can be avoided through mixing with non-flammable materials like soil or construction materials, the risk of re-emission of carbon from high-quality biochar is negligible.

When biochar is incorporated into construction materials such as concrete, it becomes an integral part of the material, effectively preventing its physical separation and degradation. As a result, biochar used in construction contributes to long-term carbon removal.

In soil, where a significant portion of biochar is applied, some degradation may occur, but only partially. To understand this, it's crucial to examine biochar's material structure, consisting of both degradable and stable fractions in soil environments. The stable fraction of biochar is characterized by extended structures with fused carbon rings, resistant to microbial degradation. Pyrogenic carbons naturally formed in wildfires exhibit similar structure and persistence, lasting in the environment for millennia.

To qualify as BCR, the stable fraction of biochar must make up at least 50% of its composition and only this fraction is accounted for carbon removal. The key to ensuring the permanence of BCR in soils is accurate indicators and analytical methods to quantify this stable fraction. Well-established molecular characterization methods are already widely used and cross-disciplinary research collaborations across soil science, organic geochemistry and petrology are further advancing biochar characterization methods.

Beyond its contribution as a carbon removal technology, biochar has impactful benefits in several sectors. In agriculture, for example, biochar isn't just beneficial — it's transformative. It boosts food security and drives agricultural sustainability. Thanks to its porous microstructure, the soil gets a lift in both structure and fertility, excelling in nutrient and water retention. And biochar's impact is tremendous for regions with tropical-weathered soils — areas where fertility often dwindles and where some of the globe's most under-resourced farmers reside.

Extensive research, including a systematic review of over 1,500 scientific papers, highlights the positive impacts of biochar in agriculture. On average, biochar application significantly increases plant productivity (+16%), crop yield (+13%), water use efficiency (+20%), soil organic carbon (+39%) and available soil nutrients (+45% for phosphorus). Furthermore, biochar can reduce emissions of nitrogen oxides (-11%) and plant heavy metal uptake (-29%).

Biochar also holds significant promise in the construction industry. By reducing the percentage of cement in concrete, biochar minimises the carbon footprint of construction materials. Astonishingly, adding just 1% by mass of biochar to concrete mixes could sequester 0.5 gigatons of CO2 annually and decrease the greenhouse gas footprint of cement-based industries by 20%. Additionally, biochar improves concrete's thermal insulation capacity and enhances mechanical properties such as compressive and flexural strength.

When introduced to soil, biochar enhances its health, promoting a thriving environment for diverse plant life. It also counters invasive species by neutralizing their toxic secretions. This dual capability makes biochar pivotal for biodiversity conservation. In BCR, adhering to the voluntary carbon market's rigorous sustainability standards is non-negotiable. These standards ensure projects source biomass responsibly, eliminating potential harm to ecosystems or food production. Biochar can sequester 0.44–2.62 gigatons of CO2 annually, balancing conservation with climate action.

The biochar industry holds immense potential, yet scaling has been constrained by limited industry awareness and production costs. Carbon removal credits can alleviate these challenges, bolstering the economic viability of BCR projects. By bridging awareness and funding gaps, these credits can help harness the full promise of biochar.

BCR offers a comprehensive blend of economic, environmental, and social benefits. In regions most affected by climate change, BCR can deliver climate justice, directing mitigation benefits where they're most needed—a sentiment reinforced by the Intergovernmental Panel on Climate Change (IPCC) 2022 report.

As the climate challenge intensifies, BCR emerges as a multi-faceted carbon removal solution. Beyond carbon sequestration, its benefits span agriculture, construction, ecosystem health and community welfare. For businesses looking for effective and reliable solutions to address the climate crisis and achieve climate goals, BCR stands out as a readily scalable technology.

With BCR credits in their portfolio of climate and removal solutions, businesses can take meaningful steps toward a more sustainable future, today.