Biochar

Industry

Old whale bone providing fertile conditions for vascular plants, Antarctic Peninsula

The concentration of GHGs in the atmosphere will have to be stabilized or lowered to mitigate or even reverse current global warming. To achieve this, current GHG emissions need to be reduced. Such mitigation strategies will however take time to deploy, and some emission sources will be difficult to mitigate. Moreover, since current atmospheric levels are already having a major warming effect, negative emission or Carbon Dioxide Removal (CDR) measures that reduce the amount of GHGs in the atmosphere are an active topic of research.

The most widely studied carbon storage technique is the large-scale application of biochar. Biochar is produced when biomass is pyrolysed - a thermal process in which oxygen for combustion is lacking. Although carbon is released during pyrolysis, this could potentially be captured, and the remaining carbon is then stabilized and can be removed from the atmospheric carbon cycle. Generally, biochar is envisioned to be used as a soil amendment, which allows carbon to be stored while benefiting soil fertility, or even to restore soil quality of degradation or polluted areas. Yet, it could also be used in production processes or stored underground.

Technological Readiness Level (TRL)

High 3

Biochar has been used throughout history, mostly in tropical areas. Although the technology therefore already exists, and can be considered amongst the most technological ready amongst CDR measures (Möllersten and Naqvi, 2022), much new research is currently being done on the properties of specific production processes and materials. An extensive literature review by Elkhlifi et al. (2023) stressed the need to develop economically viable production methods, and encouraged further research into specific production and application procedures.

Technological Readiness Level (TRL)

A technology with a TRL of 7-9: TRL 7 – prototype demonstrated; TRL 8 – system complete; TRL 9 – system proven

Scalability

Medium 2

Although the measure seems promising, uncertainties remain about the extent of the scalability of biochar (Smith et al. 2023). Chiquier et al. (2022) comparative study of carbon removal technologies suggest biochar is relatively inefficient at sequestration, and risks decreasing in efficiency due to the decay overtime. Furthermore, if biochar is produced on regular agricultural land it can take up valuable space that would otherwise be used for food or energy purposes.

Scalability

Physically somewhat scalable; linear efficiency

Timeliness for near-future effects

High 3

The technology already exists and will likely play some role in mitigating carbon emissions, but uncertainties remain about total effectiveness.

Timeliness for near-future effects

Implemented in time to make a significant difference

Northern + Arctic potential

Low 1

Although biochar has historically been mainly used in tropical areas, Lévesque et al. (2021) literature review shows certain specifically produced sorts are also beneficial to temperate areas. Since biochar application can have a multitude of other beneficial soil effects besides carbon sequestration, it might be beneficial to polluted areas in the Arctic. Studies by Karppinen et al. (2017) and Zahed et al. (2021) for example suggest biochar could be used to remediate soils that have been contaminated by hydrocarbons, especially if specific kinds of biochar production techniques are used. Tregubova et al. (2021) experimental study equally showed that biochar has a capacity to restore soils that were polluted by long term emissions of the nickel industry in the Kola peninsula.

Northern + Arctic potential

No noticeable extra positive effect beyond the global average; technology is unsuited to the Arctic

Global potential

Medium 2

Both the State of Carbon Dioxide Removal report and the IPCC AR6 wg3 report estimate a potential global carbon capture potential between 0.3 and 6.6 GtCO2/yr (Smith et al, 2023; IPCC, 2022). Although biochar will likely play an increasing role in global mitigation strategies, uncertainties however remain about the possible scale of mitigation, as uncertainties remain, for example around the potential warming effect of low-albedo biochar to soils (Meyer et al, 2012).

Global potential

Statistically detectable impacts

Cost - benefit

Medium 2

The cost of biochar application would be highly case dependent (Möllersten and Naqvi, 2022). The State of Carbon Dioxide Removal report estimates potential costs of 10 to 345 $/tCO2 (Smith et al. 2023). alongside the highly spread costing estimate, durability of sequestration should also be taken into consideration, with Chiquier et al.’s (2022) comparative CDR study finding that biochar is relatively inefficient at sequestration, and risks decreasing in efficiency due to the decay overtime.

Cost - benefit

Significant investment costs needed, but still much cheaper than the avoided damage costs (e.g., 30%).

Environmental risks

Medium 2

As mentioned above, many studies indicate possible beneficial effects of biochar application for polluted areas. There might however be negative environmental effects of the production process, and unsustainable material harvesting (Smith et al. 2023; IPCC AR6, WG3 2022). Given the already occurring increase of natural and anthropogenic black carbon in the Arctic (Stubbins et al, 2015), large-scale application of biochar in the region should likely be further studied.

Environmental risks

More widespread and possibly regional impacts that extend beyond the immediate solution deployment location

Community impacts

Beneficial 3

The IPCC AR6 WG3 report (2022) warns that poorly implemented biochar production and distribution risks causing adverse effects for local communities and ecosystems. However, biochar could also be greatly beneficial due to positive side effects on soil fertility and potential to mitigate certain toxins and increase drought resistance (Smith et al. 2023). A 2019 study by Keske et al. specifically showed that in the case of a majority indigenous inhabited remote area in Labrador, Canada, the practically free by-products of wood logging could be utilized for biochar production. The subsequent usage on the area's marginal soils could for some produce form an economic benefit and might improve food security. The authors furthermore argue that from an environmental justice standpoint, it could even be argued that the government should forward the high initial investments to create a biochar industry for a region that has been historically exploited.

Community impacts

Significant benefits to communities

Ease of reversibility

Medium 2

The biochar would decay overtime.

Ease of reversibility

Possible with significant investment

Risk of termination shock

Low 3

Risk of termination shock

Low or insignificant termination shock or damage

Legality/governance

High 3

This would fall under national legislation.

Legality/governance

Currently legal to deploy, with governance structures in place to facilitate it and/or financial incentives to develop it

Scientific/media attention

High 3

Although public attention seems limited, and popular media references more limited as opposed to more spectacular geoengineering ideas, biochar is by far the most studied CDR ideas. There are many research projects, roughly 40% of all studies on CDR methods being biochar related, and around 50% of all CDR studies published in 2021 studying biochor (Smith et al. 2023).

Scientific/media attention

Numerous scientific papers with substantial funding and ongoing research groups; significant media attention and "hype"; many companies exploring commercialization options

References

Chiquier, S., Patrizio, P., Bui, M., Sunny, N., & Mac Dowell, N. (2022). A comparative analysis of the efficiency, timing, and permanence of CO 2 removal pathways. Energy & Environmental Science, 15(10), 4389-4403. https://doi.org/10.1039/D2EE01021F

Elkhlifi, Z., Iftikhar, J., Sarraf, M., Ali, B., Saleem, M. H., Ibranshahib, I., ... & Chen, Z. (2023). Potential role of biochar on capturing soil nutrients, carbon sequestration and managing environmental challenges: a review. Sustainability, 15(3), 2527. https://doi.org/10.3390/su15032527

Karppinen, E. M., Stewart, K. J., Farrell, R. E., & Siciliano, S. D. (2017). Petroleum hydrocarbon remediation in frozen soil using a meat and bonemeal biochar plus fertilizer. Chemosphere, 173, 330-339. https://doi.org/10.1016/j.chemosphere.2017.01.016

Keske, C., Godfrey, T., Hoag, D. L. K., & Abedin, J. (2019). Economic feasibility of biochar and agriculture coproduction from Canadian black spruce forest. Food and Energy Security. https://doi.org/10.1002/fes3.188

Lévesque, V., Oelbermann, M., & Ziadi, N. (2021). Biochar in temperate soils: opportunities and challenges. Canadian Journal of Soil Science, 102(1), 1-26. https://doi.org/10.1139/cjss-2021-0047

Meyer, S.; Bright, R.M.; Fischer, D.; Schulz, H.; Glaser, B. Albedo Impact on the Suitability of Biochar Systems to Mitigate Global Warming. Environ. Sci. Technol. 2012, 46, 12726–12734. https://doi.org/10.1021/es302302g

Möllersten, K., & Naqvi, R. (2022). Technology Readiness Assessment, Costs, and Limitations of five shortlisted NETs. Available at: https://www.researchgate.net/publication/359427009_Technology_Readiness_Assessment_Costs_and_Limitations_of_five_shortlisted_NETs_Accelerated_mineralisation_Biochar_as_soil_additive_BECCS_DACCS_Wetland_restoration [Accessed 22 July 2024]

Oliveira, F. R., Patel, A. K., Jaisi, D. P., Adhikari, S., Lu, H., & Khanal, S. K. (2017). Environmental application of biochar: Current status and perspectives. Bioresource technology, 246, 110-122. https://doi.org/10.1016/j.biortech.2017.08.122

Sagarese, S. R., Frisk, M. G., Cerrato, R. M., Sosebee, K. A., Musick, J. A., & Rago, P. J. (2014). Application of generalized additive models to examine ontogenetic and seasonal distributions of spiny dogfish (Squalus acanthias) in the Northeast (US) shelf large marine ecosystem. Canadian Journal of Fisheries and Aquatic Sciences, 71(6), 847-877. https://doi.org/10.1139/cjfas-2013-0342

Smith, S. M., Geden, O., Nemet, G., Gidden, M., Lamb, W. F., Powis, C., Bellamy, R., Callaghan, M., Cowie, A., Cox, E., Fuss, S., Gasser, T., Grassi, G., Greene, J., Lück, S., Mohan, A., Müller-Hansen, F., Peters, G., Pratama, Y., Repke, T., Riahi, K., Schenuit, F., Steinhauser, J., Strefler, J., Valenzuela, J. M., and Minx, J. C. (2023). The State of Carbon Dioxide Removal - 1st Edition. The State of Carbon Dioxide Removal. https://doi.org/10.17605/OSF.IO/W3B4Z

Stubbins, A., Spencer, R. G., Mann, P. J., Holmes, R. M., McClelland, J. W., Niggemann, J., & Dittmar, T. (2015). Utilizing colored dissolved organic matter to derive dissolved black carbon export by arctic rivers. Frontiers in Earth Science, 3, 63. https://doi.org/10.3389/feart.2015.00063

Tregubova, P., Koptsik, G., Stepanov, A., Koptsik, S., & Spiers, G. (2021). Organic amendments potentially stabilize metals in smelter contaminated Arctic soils: An incubation study. Heliyon, 7(1), e06022. https://doi.org/10.1016/j.heliyon.2021.e06022

Woolf, Dominic; Amonette, James E.; Street-Perrott, F. Alayne; Lehmann, Johannes; Joseph, Stephen (10 August 2010). "Sustainable biochar to mitigate global climate change". Nature Communications. 1 (5): 56. https://doi.org/10.1038/ncomms1053

Zahed, M. A., Salehi, S., Madadi, R., & Hejabi, F. (2021). Biochar as a sustainable product for remediation of petroleum contaminated soil. Current Research in Green and Sustainable Chemistry, 4, 100055. https://doi.org/10.1016/j.crgsc.2021.100055

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Ice sheets and glaciers

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Sea ice covered Coast in July, Sterlegova, Taymyr, Russia

Sea ice & icebergs

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Land-based measures

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Large areas of the Northern and Arctic regions consist of permafrost, almost permanently frozen soil. As global temperatures rise, these permafrost areas are thawing at an ever faster rate. This thawing leads to massive amounts of GHGs being released into the atmosphere, as carbon stored in the permafrost is converted into methane by bacteria. Because methane is a very potent GHG, the thawing of the permafrost is considered a major tipping point in the climatic system. Permafrost preservation is of the utmost importance because Arctic terrestrial regions alone hold up to 1500 Pg C (Schuur et al. 2015), and although there is large uncertainty about the total amount of emissions from permafrost (Miner et al. 2022), especially when it comes to nonlinear abrupt thawing (Turetsky et al. 2020), significant amounts of carbon release is to be expected as the Northern regions warm.

Industry

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Ice sheets and glaciers

Glacier albedo increase

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Blueberries (Vaccinium myrtillus) as part of the vegetation 5 years after forest fire, Mykland, Aust Agder, Norway

Land-based measures

Rewilding

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Sea ice, North-West Spitsbergen National Park, Svalbard

Sea ice & icebergs

Sea Ice growth management

Land-based measures

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