Biochar evaluation criteria to help Compensate select the most sustainable projects on the market

Wednesday, June 15, 2022

Compensate Foundation has, in cooperation and guidance with leading biochar experts, formed criteria for evaluating all biochar projects from which it buys carbon removal credits. With the help of the biochar criteria we are now confident in buying bigger volumes of biochar credits and help scale the market. These evaluation criteria are applied to all biochar projects from May 2022 onwards and the work is funded by FedEx Express Europe. 

What is biochar?

Biochar is a man-made product, with an appearance similar to charcoal. However, it has the capability of binding up to 50% of the carbon which would otherwise be released into the atmosphere, storing it for hundreds of years. The process of creating biochar – called pyrolysis – requires heating biomass side-streams at high temperatures, without oxygen. The resulting biochar has a solid structure and a low degradation rate, which means it holds more carbon than it releases, making it one of the best-performing carbon sinks. Alongside its ability to store carbon, biochar offers several environmental co-benefits. When applied to soil, biochar boosts the properties that lead to increased soil fertility and reduces the need for irrigation.

Why biochar?

Atmospheric CO₂ emissions hit a historical record in May, reaching 421 ppm, which makes the CO₂ concentration now 50% higher than during the pre-industrial era. In the latest IPCC Sixth Assessment Report on Mitigation of Climate Change it is emphasized that to have a chance of avoiding catastrophic climate change consequences, we need not only to urgently reduce emitting more CO₂ in the atmosphere but also start removing it. 

Carbon dioxide removal (CDR), includes both nature-based removals like tree planting and technological removals through direct air capture (DAC), enhanced weathering, and biochar. While nature-based removals are easier to implement, there are many uncertainties relating to the permanence of the carbon stored - the CO₂ could be released back into the atmosphere if the trees are destroyed. Technological removals, on the other hand, provide high permanence in the range of 100 to 1000 years.

However, technological removals are not ready to scale yet to the extent needed to mitigate climate change. There are many direct air capture companies, which are receiving funding for R&D and most are still working on improving the technology to get the cost down before getting out of the lab. Biochar, on the other hand, has been around for decades, and the production technology is already developed with readiness to scale. However, the price of biochar is currently too high to allow for widespread utilization and without the carbon credit revenues, biochar industry growth will be slower and not relevant to the climate.

Biochar criteria overview

Different methodologies for biochar already exist or are being developed - European Biochar Certificate, Puro Standard, and Verra. Some are stricter than others, leaving space for biochar credits with different quality. For instance, if not captured, high methane emissions during pyrolysis can offset any carbon removal at least in the first decades after the pyrolysis. To ensure that the carbon removals are real, projects should not use default values, but conduct a thorough chemical lab analysis to assess the carbon content and stability and a life-cycle assessment of the biochar production process, distribution, and use. One tonne of biochar contains up to 3.67 tCO₂ (depending on the carbon content) and from that amount needs to be reduced all emissions from the sourcing of feedstock, transportation, the biochar production process, distribution, and application. If not all process emissions are accounted for, there is a big variation in the carbon claimed to be removed.

Carbon removals with biochar can result in carbon leakage if the biochar producer, a bioenergy company or grill charcoal, diverts part of the feedstock for biochar production. Carbon leakage occurs as a result of indirect land-use change because additional/alternative energy sources must be found when biochar production does not create enough usable energy itself. Similarly, diverting land from food production to grow energy crops for biochar might result in additional carbon removal certificates, but should we really encourage this only because someone is willing to pay a high price?

Finally, biochar should be applied in a “useful” manner to utilize most of its co-benefits in addition to storing carbon. Alongside its ability to store carbon, biochar offers several environmental co-benefits. When applied to soil, biochar boosts the properties that lead to increased soil fertility and reduces the need for irrigation.

Carbon markets should promote smart utilization of the natural resources because it is not just the climate crisis we are faced with, there is also a biodiversity crisis and a food security crisis. The increased interest in carbon removals has resulted in the notion that every activity removing carbon should be rewarded with carbon credits. Projects burying bio oil, biochar, or wood underground, just for the sake of claiming “additional” carbon removals, are wasting the potential of these valuable products to fight climate change in more ways than just removing carbon.

In addition to evaluating biochar projects considered for the Compensate carbon capture portfolio, Compensate will use the criteria in its advocacy work to reform the market, for instance, participating in public consultations for the upcoming EU-wide Carbon Removal Certificate, which considers biochar.

Photo credit: Valeria Azovskaya

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