Biomass
Biomass
Carbon removal potential: 2.5-5.5 GtCO₂/year¹
Biomass Carbon Removal and Storage (BiCRS or “bikers”) is a new umbrella term introduced by ICEF 2020¹ describing strategies that use biomass to remove CO₂ from the atmosphere and store it underground or in long-lived products. BiCRS includes bioenergy carbon capture and storage (BECCS), where biomass is burned to generate energy and CO₂ emissions are captured and stored. Negative emissions can only be achieved if the CO₂ stored is greater than the CO₂ emitted from incremental biomass production, transport, conversion and utilization. BECCS is included in the majority of modelled pathways as an essential technology to limit global warming such as the IPCC Fifth Assessment Report (2014) and IPCC 1.5℃ scenario².
BiCRS as a carbon removal pathway was conceived twenty years ago, and while today, there are a number of operational BiCRS facilities actively capturing and storing carbon, we believe the current capacity is only 2.5 MtCO₂ gross removals each year with ~25 MtCO₂/yr in planning or development¹. That is 1000-2000 times smaller than the 2.5-5.5 GtCO₂/yr potential of BiCRS. It should be noted that the net emissions from these facilities are still positive meaning the carbon emitted in production and operation is greater than that being stored. Major challenges to scalability include the availability of sufficient, sustainable, consistent and contaminant-free feedstocks and the capital and operational cost of biomass conversion plants, even before the additional overhead of carbon capture and storage. Feedstock characteristics, such as relative lignocellulose content and biogenic ash concentrations can cause complications or impact the efficiency of the conversion process. In addition, BiCRS must scale responsibly without the production of biomass damaging food or water security, rural livelihoods or biodiversity.
There is a wide range of potential biomass solutions. With carbon removal markets placing greater premiums on permanent CO₂ removal, burial solutions have recently grown in prominence alongside more established bioenergy pathways and may well be more efficient as a carbon removal pathway. Or pyrolysing waste biomass can, for instance, form biochar, a dense stable form of carbon that has many under-exploited applications, from soil enrichment to water stabilising, pollution management and waste treatment or even, potentially, in steel production. Carbon negative bioenergy applications also continue to broaden and valuable by-products of waste biomass could help drive the industry forward, particularly given the capital costs involved in many pathways.
Benefits:
Carbon storage by BiCRS is more durable than storage in living biomass.
Biomass conversion can create useful products like green hydrogen and biochar, adding value beyond carbon removal and compensating for high capital costs.
The CO₂ produced from the conversion process is concentrated and therefore easy to capture.
Biomass conversion processes:
Combustion
Fermentation
Gasification
Pyrolysis
Burial
Biomass feedstocks:
Waste (forestry, orchards, agriculture, industrial, municipal)
Bioenergy crops
Micro/macroalgae
Issues we care about:
The process needs to be net negative, from growing to transporting, converting and storing.
As carbon removal strategies scale into the gigatons, pathways can not displace land and challenge food security.
Capitalising on waste as feedstock, taking extra care not to cause harm by displacing other crops or impacting bio-diversity.
Considering the most efficient feedstock for the conversion process, with more positives and fewer negatives than other potential uses.
Ensuring scalability by exploring commercially desirable products that help make the economics work.
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