Biochar deployment in net zero scenarios: Identification of industrial feasibility constraints

According to the IPCC, carbon dioxide removal is unavoidable to reach the Paris Agreements climate targets C (Shukla et al., 2022). Carbon dioxide removal include all human activities aiming at removing carbon dioxide from the atmosphere and durably storing it (Smith et al., 2024). Biochar is a carbon-dense, biogenic charcoal produced through the pyrolysis of biomass, which transforms the carbon content originating from atmospheric CO2 (fixed through photosynthesis) into a more stable form of carbon for long term storage. This process also co-produces syngas and bio-oil and, once applied to agricultural soil, biochar can increase crop yields. Biochar is one of the mature CDR methods that private investors invest in the most. In 2023, it represented more carbon removed from the atmosphere than Bioenergy with Carbon Capture and Storage (BECCS) and Direct Air Capture with CCS (DACCS) combined (Pongratz et al., 2024), with a global market worth $600 millions (Global Biochar Market Soars to $600 Million in 2023, Setting the Stage for Future Growth, 2024). However, Biochar is much less included in Integrated Assessment Models (IAM) scenarios than the two others less mature CDR technologies, with only two scenarios accounting for biochar in the latest IPCC report compared to 280 for DACCS (Byers et al., 2022). Certain scenarios were shown to rely too heavily on BECCS and CCS to reach our climate targets (Kazlou et al., 2024; Workman et al., 2021), questioning our ability to meet our climate targets and our aim is to identify of it is the case for Biochar. IPCC scenarios accounting for biochar plan for an acceleration phase until 2040 stabilizing until 2100 with a maximum of 2,4 Gt CO2 in 2050 (Byers et al., 2022). The objective of this paper is to analyze the industrial feasibility of biochar, beyond the hype in the private sector and the lack of data in the scientific literature. Biochar industrial development challenges existing scenarios and offers new realistic estimates for the potential of carbon dioxide removal with a mature technology. In this paper, we will investigate the potential and industrial limitations of Biochar as a contributor to Net Zero efforts.