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Biochar Production and Storage
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This Protocol (A document that describes how to quantitatively assess the net amount of CO₂ removed by a process. To Isometric, a Protocol is specific to a Project Proponent's process and comprised of Modules representing the Carbon Fluxes involved in the CDR process. A Protocol measures the full carbon impact of a process against the Baseline of it not occurring.) provides the requirements and procedures for the calculation of net carbon dioxide equivalent (CO2e (The amount of CO₂ emissions that would cause the same integrated radiative forcing or temperature change, over a given time horizon, as an emitted amount of GHG or a mixture of GHGs. One common metric of CO₂e is the 100-year Global Warming Potential.)) Removal (The term used to represent the CO₂ taken out of the atmosphere as a result of a CDR process.) from the atmosphere viathrough the production of biochar and its durable Storage (Describes the addition of carbon dioxide removed from the atmosphere to a reservoir, which serves as its ultimate destination. This is also referred to as “sequestration”.).
Biochar is a chemically durable, carbon-rich solid material produced from the pyrolysis of biomass. Pyrolysis is a thermochemical conversion process, where biomass is heated in an oxygen free environment to produce a mixture of solid biochar andas well as condensable and non-condensable gasses. This process chemically stabilizes the carbon in the biomass, originally captured by plants through photosynthesis, preventing it from returning to the atmosphere through natural decomposition, or combustion, and thereby contributing to long-term carbon removal.
Upon production, all biochar consists of a reactive organic carbon pool, the more easily degradable compounds, and a non-reactive fraction, the stable polyaromatic structures. The proportions of which are highly affected by the biomass feedstock (Raw material which is used for CO₂ Removal or GHG Reduction.) composition, as well as the pyrolysis conditions it is exposed to. There are a growing number of examples of biochar being stable in the environment at centennial and millennial scale. One of the most-cited and tangible examples of this is Terra Preta - soil enriched with biochar in the Amazon Basin, which has been radiocarbon-dated to up to 7,000 years 1. Demonstrating the remarkable durability (The amount of time carbon removed from the atmosphere by an intervention – for example, a CDR project – is expected to reside in a given Reservoir, taking into account both physical risks and socioeconomic constructs (such as contracts) to protect the Reservoir in question.) of biochar, even in some of the most extreme tropical soil environments that are known for their rapid breakdown and cycling of nutrients and organic matter. Alongside Terra Preta and other global analogues in Europe2, Australia3, and Africa4, there are numerous examples of char that persists for millennia in soils, including that produced by wildfires5,6,7.
Biochar's chemical properties, dictate its durability by influencing its stability and how it interacts with its environment. Generally, feedstocks exposed to higher temperature (> 500°C) pyrolysis conditions translate to increased biochar stability, leading to the formation of a larger volume of stable polyaromatic structures8. Polyaromatic structures are highly recalcitrant to both biotic (through the action of marco- and micro- organisms and plants) and abiotic (UV, oxidation, temperature and moisture) breakdown9. A higher H/C ratio indicates less stable biochar, while a high degree of aromatic carbon (low H/C) and low oxygen content (low O/C ratio) signifies greater chemical stability and durability, especially from biochar produced at high temperature.
Isometric offers several storage options for biochar produced by pyrolysis, suchtheses asinclude application to surface soil in agricultural settings, burial in the shallow subsurface, and incorporation into buildingmaterials materialsin the built environment. In each of these settings, a substantial fraction of the organic carbon content can be stored durably. The amount of carbon stored within biochar may decrease over time if the biochar is exposed to oxidizing conditions. Several physical and chemical properties of the biocharNevertheless, as well as environmental factors associated with the application site, affect the rate at which organic carbon in the biochar can be potentially released back into the atmosphere. Thisthis Protocol adopts a conservative (Purposefully erring on the side of caution under conditions of Uncertainty by choosing input parameter values that will result in a lower net CO₂ Removal or GHG Reduction than if using the median input values. This is done to increase the likelihood that a given Removal or Reduction calculation is an underestimation rather than an overestimation.) approach to crediting, with only the highly durable fraction of the organic carbon content inof the biochar being eligible for the generation of Credits (A publicly visible uniquely identifiable Credit Certificate Issued by a Registry that gives the owner of the Credit the right to account for one net metric tonne of Verified CO₂e Removal or Reduction. In the case of this Standard, the net tonne of CO₂e Removal or Reduction comes from a Project Validated against a Certified Protocol.).
All quantification of biochar durability for carbon crediting to date are based on modeling studies using the initial biochar characteristics, namely H:C ratios, or comparison to geological (inertinite) proxies (A measurement which correlates with but is not a direct measurement of the variable of interest.) combined with the organic carbon (Corg) content. The production process through which the biochar is created and the Module (Independent components of Isometric Certified Protocols which are transferable between and applicable to different Protocols.) through which the biochar is being stored will determine which method is most appropriate for quantifying durability and the associated carbon crediting duration.
This Protocol accountssets out the requirements and methods for the quantification of the gross amount of CO2 removed via the production and durable storage (Describes the addition of carbon dioxide removed from the atmosphere to a reservoir, which serves as its ultimate destination. This is also referred to as “sequestration”.) of biochar and all cradle-to-grave (Considering impacts at each stage of a product's life cycle, from the time natural resources are extracted from the ground and processed through each subsequent stage of manufacturing, transportation, product use, and ultimately, disposal.) life-cycle Greenhouse Gas (GHG) (Those gaseous constituents of the atmosphere, both natural and anthropogenic (human-caused), that absorb and emit radiation at specific wavelengths within the spectrum of terrestrial radiation emitted by the Earth’s surface, by the atmosphere itself, and by clouds. This property causes the greenhouse effect, whereby heat is trapped in Earth’s atmosphere (CDR Primer, 2022).)emissions (The term used to describe greenhouse gas emissions to the atmosphere as a result of Project activities.) associated with the process, to determine the netgross carbon dioxide equivalent (CO2e) removal.
This ProtocolIt is developed to adhere to the requirements of ISO (A worldwide federation (NGO) of national standards bodies from more than 160 countries, one from each member country.) 14064-2: 2019 – Greenhouse Gasses – Part 2: Specification with guidance at the Project (An activity or process or group of activities or processes that alter the condition of a Baseline and leads to Removals or Reductions.) level for quantification, monitoring, and reporting of greenhouse gas emission reductions (Lowering future GHG releases from a specific entity.) or removal enhancements. ThisEnsuring Protocol ensuresthat:
This Protocol mainly utilizes and is intended to be compliant with the following standards and protocolsProtocols:
Additional reference standards that inform the requirements and overall practices incorporated in this Protocol include:
Additional standards, methodologies and protocolsprinciples that were reviewed,considered referencedin or for which attempts were made to align with or leverage duringthe development of this Protocol and aligned with, where feasible, include:
Protocols and Methodologies that were assessed as part of a literature review during the development of this Protocol include:
This Protocol was developed based on the current state of the art, publicly available science regarding biochar production and storage. The Protocol will be updated in future versions as the science underlying biochar production and storage evolves and the overall body of knowledge and data across all processes is increased, for examples regarding Feedstock (Raw material which is used for CO₂ Removal or GHG Reduction.) supply, thermochemical conversion, and durable storage.
This Protocol will be reviewed at a minimum every 2 years and/or when there is an update to scientific published literature which would affect net CO₂e removal quantification or the monitoring guidelines outlined in this Protocol. Because biochar production and storage is a novel Carbon Dioxide Removal (CDR) (Activities that remove carbon dioxide (CO₂) from the atmosphere and store it in products or geological, terrestrial, and oceanic Reservoirs. CDR includes the enhancement of biological or geochemical sinks and direct air capture (DAC) and storage, but excludes natural CO₂ uptake not directly caused by human intervention.) approach, this Protocol incorporates requirements that may be more stringent than some current relevant regulations or other protocolsProtocols related to biochar for CDR. In particular, requirements for demonstrating Durability (The amount of time carbon removed from the atmosphere by an intervention – for example, a CDR project – is expected to reside in a given Reservoir, taking into account both physical risks and socioeconomic constructs (such as contracts) to protect the Reservoir in question.)Durability of biochar will be updated as the stability of CO2carbon captured by biochar becomes wellbetter demonstrated and documentedunderstood, and biochar degradation is proven to be limited. Nevertheless this Protocol adopts a conservative approach to crediting and risk to ensure the integrity of carbon Credits issued against it.
Additionally, this Protocol will be reviewed when there is an update to published scientific literature, government policies, or legal requirements which would affect net CO2e removal quantification or the monitoring guidelines outlined in this Protocol, or at a minimum of every 2 years.
This project applies to projects or processes which:
This Protocol applies to projects and associated operations that meet all of the following project conditions:
FollowingIn line with the Isometric Standard, the issuance (Credits are issued to the Credit Account of a Project Proponent with whom Isometric has a Validated Protocol after an Order for Verification and Credit Issuance services from a Buyer and once a Verified Removal or Reduction has taken place.) of Credits under this Protocol areis contingent onupon the implementation, transparent reporting, and independent Verification (A process for evaluating and confirming the net Removals and Reductions for a Project, using data and information collected from the Project and assessing conformity with the criteria set forth in the Isometric Standard and the Protocol by which it is governed. Verification must be completed by an Isometric approved third-party (VVB).) of comprehensive safeguards. These safeguards encompass a wide range of considerations, includingcover environmental protection, social equity, community engagement, and respect for cultural values. The process mandates that safeguardSafeguard plans must be incorporatedintegrated into all major projectphases phasesof the Project, with detailed reports made accessibleavailable to Stakeholders (Any person or entity who can potentially affect or be affected by Isometric or an individual Project activity.). Adherence to, and verificationVerification of, these environmental and social safeguards is a mandatory condition for all Crediting Projects.
Project Proponents (The organization that develops and/or has overall legal ownership or control of a Removal or Reduction Project.) must comply with all national and local laws, regulations, and policies in line with the Isometric Standard. Project Proponents are required to document all activities (The steps of a Project Proponent’s Removal or Reduction process that result in carbon fluxes. The carbon flux associated with an activity is a component of the Project Proponent’s Protocol.) conducted under the Project that necessitate environmental permits, including the permits obtained and receivethe authorities that issued them, in the Project Design Document (The document, written by a permitProject Proponent, which records key characteristics of a Project and which forms the basis for anyProject projectValidation activitiesand undertakenevaluation fromin accordance with the relevant authorityCertified Protocol. Where(Also relevantknown as “PDD”).) (PDD).
Where applicable, projects must also comply with international conventions and standards related to human rights and environmental protection, particularly when conductedactivities occur within or foreseeablyhave impactingforeseeable impacts on jurisdictions that are party jurisdictionsto such agreements.
Project Proponents must document activities conducted under The Project that would require it to obtain environmental permits.
The Project must assess environmental and social impacts across all project locations—including biomass sourcing areas, pyrolysis facilities, biochar deployment sites, and biomass or biochar transportation routes.
[/G-4REH-1]Appropriate measures must be implementedin place to identify and eliminate potential risks to terrestrial and aquatic ecosystems and biodiversity (The diversity of life across taxonomic and spatial scales. Biodiversity can be measured within species (i.e. genetic diversity and variations in allele frequencies across populations), between species (i.e. the total number and abundance of species within and across defined regions), within ecosystems (i.e. the variation in functional diversity, such as guilds, life-history traits, and food-webs), and between ecosystems (variation in the services of abiotic and biotic communities across large, landscape-level scales) that support ecoregions and biomes.). Where risks cannot be eliminated, the ProjectPDD Designmust Documentoutline (PDD)a (Theproject-specific documentmitigation plan that clearly outlines how a Project will generate rigorously quantifiable Additional high-quality Removals or Reductions.) must identifyincludes measures to monitor ecosystem health and mitigateaddress adverse effects through a project-specific mitigation plan. Mitigation plans must be carried out by subject matter experts, in consultation with Isometric. Refer to Section 3.7 of the Isometric Standard for further guidelines on environmental and social impacts.
Environmental and social risk assessment in adherence with Section 3.7 of the Isometric Standard must be completed to identify potential risks, followed by the development of tailored mitigation plans. These plans must encompass specific actions to avoid, minimize or rectify identified impacts. Effective implementation of these measures must also be accompanied by a robust monitoring plan to detect negative impacts and stop projects when necessary.
The severity of these risks vary baseddepends on site-specific specificsconditions and on the intensity and duration of project activities. EnvironmentalEach andProject socialmust conduct risk identification, assessment, avoidance, and mitigation planning willin bea uniqueway tothat eachreflects Project’sits own technical, environmental, and social contextscontext.
The risks identifiedoutlined in this Protocol arerepresent a minimum set toof whichrequired considerations. Additional risks may be identified by Isometric andor the Project Proponent can add risks on a case -by -case basis, whichand wouldmust be included in the PDD.
The Project Proponent must conduct an environmental risk assessment which adheres to Section 3.7.1 of the Isometric Standard. PotentialBiochar additionalProduction and storage has the potential to contaminate of soil, water, or surrounding ecosystems through improper use. The specific nature and magnitude of these risks depend on factors such as feedstock composition, production technology, operating conditions, and storage practices and rates. Appropriate controls, monitoring, and compliance with relevant environmental risksstandards are necessary to minimize potential impacts. For example, there is more environmental risk associated with biochar productionapplication to soils (particularly agricultural soils) due to the potential impact on ecosystem service provision, compared to biochar encapsulated in the built environment and low oxygen environments. All storage environments require at least a declaration of quantity of potential pollutants contained within the biochar, with lower thresholds in soil storage environments to mitigate environmental risk. Potential pollutants of concern for environmental and human health are listed below.
Polycyclic Aromatic Hydrocarbons (PAHs) and heavy metals are pollutants of concern that may be found in biochar110,211:
Projects must evidence that pollutants are within the upper bound limits for thesethe parametersassociated pollutants set by World Biochar Certificate (WBC).
The Project Proponent must conduct a social risk assessment which adheres to Section 3.7.2 of the Isometric Standard on social impacts. In particular, this should include specific risks to human health that may be associated with biochar production, application and/or storage during the Project, for example risk of dust inhalation during transport and application due to dust.
In accordance with Section 3.5 of the Isometric Standard, Project Proponents must demonstrate active stakeholder engagement through a Stakeholder Input Process throughout project planning and operation, ensuring that all risk mitigation strategies contribute to sustainable project outcomes. Local stakeholders situated in the vicinity of the Projectproject site may contribute an in-depth understanding of the local system and provide invaluable insights and recommendations on the potential risks, necessary safeguards and specific monitoring needs. The Stakeholder Input Process must adhere to requirements outlined in Section 3.5 of the Isometric Standard, and evidence of these meetings must be submitted in the PDD.
Community engagement is not required in biochar offtake (A contract in which a Buyer agrees to purchase a set Removal and/or Reduction at a set price.) locations where biochar is sold or transferred through a commercial transaction. However, where biochar is distributed or applied without financial exchange (e.g., donated or provided free of charge), the Project Proponent must conduct appropriate stakeholder consultation to ensure that recipients and local communities are informed of potential impacts and consent to its use.
Project Proponents must include in the PDD a plan for information sharing, emergency response and conditions for stopping or pausing a deployment.
[/R-BC4H-1]Plans for pausing or stopping a deployment must be in place in instances where there may be:
The following topics are covered briefly in this Protocol due to their inclusion in the Isometric Standard, which governs all Isometric Protocols. See in-text references to the Isometric Standard for further guidance.
For each specific projectProject to be evaluated under this Protocol, the Project Proponent must document project characteristics in a Project Design Document (PDD) as outlined in Section 3.2 of the Isometric Standard. The PDD will form the basis for Project Validation (A systematic and independent process for evaluating the reasonableness of the assumptions, limitations and methods that support a Project and assessing whether the Project conforms to the criteria set forth in the Isometric Standard and the Protocol by which the Project is governed. Validation must be completed by an Isometric approved third-party (VVB).) and evaluation in accordance with this Protocol, and must include consideration of processes unique to biomass such as:
Projects must be validated and net CO2e removals verified by an independent third party, a Validation and Verification Body (VVB (Third-party auditing organizations that are experts in their sector and used to determine if a project conforms to the rules, regulations, and standards set out by a governing body. A VVB must be approved by Isometric prior to conducting validation and verification.)), consistent with the requirements described in this Protocol and in Section 4 of the Isometric Standard.
The Validation and Verification Body (VVB) must consider the following requisite components:
The threshold for Materiality (An acceptable difference between reported Removals/emissions or Reductions/emissions and what an auditor determines is the actual Removal/emissions or Reduction/emissions.), considering the totality of all omissions, errors and mis-statements is 5%, in accordance with Section 4.3 of the Isometric Standard.
Verifiers must also verify the documentation of Uncertainty (A lack of knowledge of the exact amount of CO₂ removed by a particular process, Uncertainty may be quantified using probability distributions, confidence intervals, or variance estimates.) of the GHG Statement as required by Section 2.5.7 of the Isometric Standard. Qualitative Materiality issues may also be identified and documented, such as:
Project validationValidation and verificationVerification must incorporate site visits to project facilities in accordance with the requirements of ISO 14064-3, 6.1.4.2. This is to include, includingat a minimum, site visits during validationthe andfirst initialValidation verificationor Verification of a Project, to the biomass pyrolysis site and the biochar application site.
A site visit must occur at least once during each Project Validation. Additional site visits may be required if there are substantial changes to field operations over the course of a Project's Validation period, or if deemed necessary by Isometric or the VVB. Site visit plans are to be determined according to the VVB's internal assessment, in consultation with Isometric.
In the instance of multiple application sites under a single verification event, a representative number of application sites can be selected for the site visits. Validators should, whenever possible, observe operation of the biochar processing and deployment to ensure full documentation of process inputs and outputs through visual observation. Guidanceand on the numbervalidation of sitesinstrumentation, to be taken as a "representative" number here should be outlined in the PDDmeasurements, and agreedrequired upondata withquality Isometric prior to verification. In cases where it is not possible to line up site visits to the pyrolysis site and application site, alternative arrangements may be agreed in advance with Isometric, for example using photo and video evidence of activities at the application site, and/or introducing spot check site visits for ongoing operationsmeasures.
Verifiers and validators must comply with the requirements defined in Section 4 of the Isometric Standard. In addition, teams must maintain and demonstrate expertise associated with the specific technologies of interest, including biomass growth or production, biomass processing and pyrolysis, sampling, analysis, and data processing, and material storage.
Competency must be demonstrated in accordance with Isometric's VVB policy, for example based on the relevant sectoral scope accreditations in IAF MD 14, or another demonstration of relevant expertise for this protocolProtocol and the selected storage moduleModule(s).
CDR via biochar is often a result of a multi-step process (such as biomass growth, harvesting, transport, pyrolysis, processing, and storage), with activities in each step potentially managed and operated by a different operator, company, or owner. When there are multiple parties involved in the process, and to avoid Double Counting (Improperly allocating the same Removal or Reduction from a Project Proponent more than once to multiple Buyers.) of net CO2e removals, a single Project Proponent must be specified contractually as the sole owner of the Credits. Contracts must comply with all requirements defined in Section 3.1 of the Isometric Standard.
The Project Proponent must be able to demonstrate Additionality (An evaluation of the likelihood that an intervention—for example, a CDR Project—causes a climate benefit above and beyond what would have happened in a no-intervention Baseline scenario.) through compliance with Section 2.5.3 of the Isometric Standard. The baseline (A set of data describing pre-intervention or control conditions to be used as a reference scenario for comparison.) scenario and counterfactual (An assessment of what would have happened in the absence of a particular intervention – i.e., assuming the Baseline scenario.) utilized to assess additionality must be project-specific, and are described in Section 7.2 of this Protocol.
Additionality determinations should be reviewed and completed at the time of initial verification or whenever project operating conditions change significantly, such as the following:
Any review and change in the determination of additionality shall not affect the availability of Carbon Finance and Credits for the current or past Crediting Periods (The period of time over which a Project Design Document is valid, and over which Removals or Reductions may be Verified, resulting in Issued Credits.). If the review indicates the Project has become non-additional, this shall make The Project ineligible for future Credits413.
The uncertainty in the overall estimate of the net CO2e removal as a result of the Project must be accounted for. The total net CO2e removed for a specific Reporting Period, [math: RP], (Reporting Period) CO2eRemoval, RP, must be conservatively (Purposefully erring on the side of caution under conditions of Uncertainty by choosing input parameter values that will result in a lower net CO₂ Removal or GHG Reduction than if using the median input values. This is done to increase the likelihood that a given Removal or Reduction calculation is an underestimation rather than an overestimation.) determined in accordance with the requirements outlined in Section 2.5.7 of the Isometric Standard.
Projects must detail and justify their uncertainty analysis and any uncertainty adjustments (e.g. %) applied in instances of high uncertainty.
[/R-Z106-1]Including:
The uncertainty information should at least include the minimum and maximum values of a variable. More detailed uncertainty information should be provided if available, as outlined in Section 2.5.7 of the Isometric Standard.
[/G-JV4P-1]In addition, a sensitivity analysis (An analysis of how much different components in a Model contribute to the overall Uncertainty.) that demonstrates the impact of each input parameter’s uncertainty on the final net CO2e uncertainty must be provided. Details of the sensitivity analysis method must be provided such that a third party can reproduce the results. Input variables may be omitted from an uncertainty analysis if they contribute to a < 1% change in the net CO2e removal. For all other parameters, information about uncertainty must be specified.
In accordance with the Isometric Standard, all evidence and data related to the underlying quantification of the net CO₂2e removal and environmental and social safeguards monitoring will be available to the public through Isometric's platform. This includes:
The Project Proponent can request certain information to be restricted (only available to authorized Buyers (An entity that purchases Removals or Reductions, often with the purpose of Retiring Credits to make a Removal or Reduction claim.), the Registry (A database that holds information on Verified Removals and Reductions based on Protocols. Registries Issue Credits, and track their ownership and Retirement.) and Validation and Verification Bodies (VVBs) (Third-party auditing organizations that are experts in their sector and used to determine if a project conforms to the rules, regulations, and standards set out by a governing body. A VVB must be approved by Isometric prior to conducting validation and verification.)) where it is subject to confidentiality. This includes emissions factors from licensed databases. However, all other numerical data produced or used as part of the quantification of net CO₂2e removal will be made available.
The scope of this Protocol includes GHG sources (Any process or activity that releases a greenhouse gas, an aerosol, or a precursor of a greenhouse gas into the atmosphere.), sinks (Any process, activity, or mechanism that removes a greenhouse gas, a precursor to a greenhouse gas, or an aerosol from the atmosphere.) and reservoirs (A location where carbon is stored. This can be via physical barriers (such as geological formations) or through partitioning based on chemical or biological processes (such as mineralization or photosynthesis).) (SSRs) (Sources, Sinks and Reservoirs) associated with a biochar CDR project.
A cradle-to-grave (Considering impacts at each stage of a product's life cycle, from the time natural resources are extracted from the ground and processed through each subsequent stage of manufacturing, transportation, product use, and ultimately, disposal.) GHG Statement must be prepared encompassing the GHG emissions relating to the activities outlined within the system boundary.
GHG emissions associated with The Project may be as direct emissions (Emissions that are produced by a specific CDR process and are directly controllable.) from a process or storage system or as indirect emissions from combustion of fuels, electricity generation, or other sources.
Emissions must include all GHG SSRs within the system boundary, from the construction or manufacturing of each physical site and associated equipment, closure and disposal of each site and associated equipment, and operation of each process, including Embodiedembodied Emissionsemissions (Life cycle GHG emissions associated with production of materials, transportation, and construction or other processes for goods or buildings.) of equipment and consumables used in The Project. The Project Proponent is responsible for identifying all sources of emissions directly or indirectly related to project activities.
Any emissions from sub-processes or process changes that would not have taken place without the CDR project, such as subsequent transportation and refining,Project must be fully considered in the system boundary.
Any Biomassactivity feedstockthat (Rawultimately materialleads whichto isthe usedissuance forof CO₂ Removal or GHG Reduction.) emissionsCredits must be calculated as outlinedincluded in the Biomasssystem Feedstock Accounting Moduleboundary. This allows for accurate consideration of additional
The system boundary must include all SSRs controlled by and related to theThe Project, including but not limited to the SSRs in Figure 1 and Table 1. If any GHG SSRs within Table 1 are deemed not appropriate to include in the system boundary, they may be excluded provided that robust justification and appropriate evidence is provided in the PDD.
Figure 1: Process flow diagram showing system boundary for biochar projects[Image:
Figure 1]
Table 1. Scope of activities and GHG SSRs to be included in the system boundary
Activity | GHG Source, sink or reservoir | GHG | Scope | Timescale of emissions and accounting allocation |
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Project Establishment | Equipment and materials manufacture | All GHGs | Embodied emissions associated with equipment and materials manufacture for project establishment (lifecycle | Before project operations start - must be accounted for in the first Reporting Period or amortized in line with allocation rules (See Section 8. |
Equipment and materials transport to site | All GHGs | Transport emissions associated with transporting materials and equipment to | ||
Construction and installation | All GHGs | Emissions related to construction and installation of the project site(s) (lifecycle | ||
Initial surveys and feasibility studies | All GHGs | Any embodied, energy and transport emissions associated with surveys or feasibility studies required for establishment of the project site. | ||
Misc. | All GHGs | Any SSRs not captured by categories above, for example staff transport. | ||
Operations | Biomass feedstock sourcing | All GHGs | Any embodied, energy and transport emissions associated with biomass cultivation and harvesting. | Over each Reporting Period - must be accounted for in the relevant Reporting Period (See Section 8. |
Biomass feedstock transport | All GHGs | Transport of biomass including to biomass processing site and all other transport of biomass ahead of biochar production. | ||
Biomass feedstock processing | All GHGs | Any embodied, energy and transport emissions associated with biomass feedstock processing. | ||
Pyrolysis | All GHGs | Emissions associated with pyrolysis including:
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Direct emissions | All GHGs | Direct emissions released during pyrolysis. See Section | ||
Biochar processing | All GHGs | Emissions associated with biochar processing and characterization including:
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Biochar transport | All GHGs | All transport of biochar including to biochar processing site and to the biochar storage site. | ||
Biochar storage | All GHGs | Emissions associated with biochar storage (e.g. spreading on agricultural fields) including:
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CO₂ Stored | CO₂ only | The gross amount of CO₂ removed and durably stored from a biochar project over a Reporting Period. | ||
Sampling required for MRV (The multi-step process to monitor the Removals or Reductions and impacts of a Project, report the findings to an accredited third party, and have this third party Verify the report so that the results can be Certified.) | All GHGs | Any embodied, energy and transport emissions associated with sampling for MRV purposes, including transportation to collect samples, shipping of samples for laboratory analysis and sample processing. | ||
Staff travel | All GHGs | Flight, car, train or other travel required for | ||
Surveys | All GHGs | Equipment, energy use and transport associated with surveys e.g. ecological surveys. | ||
Misc. | All GHGs | Any SSRs not captured by categories above. | ||
End-of-Life | End-of-life of project facilities | All GHGs | Anticipated end-of-life emissions (lifecycle | After Reporting Period - must be accounted for in the first Reporting Period or amortized in line with allocation rules (See Section 8. |
Misc. | All GHGs | Any emissions SSR not captured by categories above. |
Miscellaneous GHG emissions are those that cannot be categorized by the GHG SSR categories provided in Table 1.
The Project Proponent is responsible for identifying all sources of emissions directly or indirectly related to project activities and must report any outside of the SSR categories identified as miscellaneous emissions.
[/G-CJYA-1]Emissions associated with The Project's impact on activities that fall outside of the system boundary of The Project must also be considered. This is covered under Leakage (The increase in GHG emissions outside the geographic or temporal boundary of a project that results from that project's activities.) in Section 8.6.4.
[/G-KWNM-1]In some instances, the project activities may be integrated into existing activities, such as biochar spreading while tilling. Activities that were already occurring, and would continue to occur in the absence of The Project, may be omitted from the system boundary of the GHG accounting if evidence of this is provided.
In line with the GHG Accounting Module v1.0, The Project must:
For all other activities all GHGs must be considered. For example, the release of CO2, CH4, and N2O is expected during diesel consumption.;
Miscellaneous; GHGand
Emissions associatedline with aIsometric project's impact on activities that fall outside of the system boundary of a project must also be consideredrequirements. This is covered under Leakage (The increase in GHG emissions outside the geographic or temporal boundary of a project that results from that project's activities.) in Section 8.5.4.
Project boundaryProponents considerations
AncillarySSRs activitieswhere (suchthe astotal supplementaryemissions researchfor that SSR, and developmentall activitiesexcluded andSSRs corporate administrative activities) thatcollectively, are associated with a project but are not directly or indirectly related to the issuance of Credits can be excluded from the system boundary.
Biochar may have additional impacts on GHG emissions beyond the scope of this Protocol. For example, there may be potential for increased Soil Organic Carbon (SOC) as a result of biochar application to soil. These potential secondary climate effects are uncertain at this time and are not covered by this Protocol.
Embodied emissions associated with system inputs consideredexpected to be wastenegligible. productsNegligible canSSRs beare excludedthose fromwhich fall below a Materiality threshold based on environmental significance of < 1% of net CO2e removals. Project Proponents must follow the accountingMateriality assessment requirements set out in Section 5 of the GHG Statement system boundary provided the appropriate eligibility criteria are met.
For waste energy inputs, for example the use of waste heat, refer to the Energy Use Accounting Module v1.2.
Refer to Energy Use Accounting Module for the calculation guidelines.
For waste biomass feedstocks, refer to the Biomass Feedstock Accounting Module v1.2. All eligibility criteria described in the Biomass Feedstock Accounting Module must be satisfied in order to exclude biomass sourcing emissions from the system boundary. Emissions relating to any processing and transport of biomass feedstock must be included in the system boundary.
See Biomass Feedstock Accounting Module for eligibility criteria.
For all other waste inputs, the following criteria shall be considered. If EC1 in Table 2 is satisfied, embodied emissions associated with the waste product input can be excluded from the system boundary. Market leakage emissions associated with waste inputs may also be excluded from the system boundary, as compliance with EC1 would result in no change to the waste producer behavior (i.e. no market leakage) and indicates there are no alternative users of the waste product (i.e. no replacement emissions (Any emissions that occur to compensate for biomass that was previously serving another purpose and is now being used for carbon removal or GHG reduction. For example, if agricultural waste was previously left on a field to decompose - fertilizer production to replace those nutrients need to be accounted for.)).
Table 2. Waste input emissions exclusion criteria, EC1
If EC2 and EC3 in Table 3 are both satisfied, embodied emissions associated with the waste product input can be excluded from the system boundary. Market leakage emissions associated with waste inputs may also be excluded from the system boundary, as compliance with EC2 and EC3 would result in no significant change to the waste producer behavior (i.e. no market leakage) and there are no alternative use cases for the waste product (i.e. no replacement emissions).
Table 3. Waste input emissions exclusion criteria, EC2 and EC3
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In some instances, the project activities (The steps of a Project Proponent’s Removal or Reduction process that result in carbon fluxes. The carbon flux associated with an activity is a component of the Project Proponent’s Protocol.) may be integrated into existing activities, such as biochar spreading while tilling. Activities that were already occurring, and would continue to occur in the absence of The Project, may be omitted from the system boundary of the GHG accounting if evidence of this is provided.
The biomass pyrolysis process may result in the production of co-products, such as bio-oil (A mixture of water, organic acids, aldehydes, ketones, sugars, phenols, and other organic compounds derived from the thermal breakdown of biomass. Thermal breakdown of biomass is achieved via thermochemical processes, such as pyrolysis, which heat biomass in low- or no-oxygen environments to high temperatures (~e.g. 350-650°C). Bio-oil is often also referred to as pyrolysis oil or bio-crude.), pyrolysis gas (bio-gas), electricity and heat. To allocate project emissions associated with CDR and co-product(s), the Project Proponent may use one or a combination of, where relevant, the following co-product allocation procedures outlined below.
Procedure 1: Allocate all emissions to CDR
Projects may opt to allocate all project emissions to CDR. The co-product(s) must still comply with all relevant emission accounting regulations and requirements, which may mean emissions are double counted. Removals must not be double counted. This is the most conservative approach to take.
Procedure 2: Divide the process into sub-processes
Where possible, the process may be divided into sub-processes. For example it may be possible to isolate processes relating to processing of the co-product, or the biochar process may be a retrofit to an existing process.
Eligibility criteria, evidence requirements and GHG system boundary considerations are set out in Table 4. One of EC4 or EC5 must be satisfied in order to divide the process into sub-processes.
Table 4. Procedure 2 Eligibility Criteria, EC4 and EC5
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Procedure 3: Substituting emissions
Project Proponents may use the substitution method to incorporate emissions associated with a substitute co-product into the system boundary as an avoided burden. This is referred to as "expanding the system boundary" in ISO 14044:2006. In practice, the co-product emissions are substitutes with emissions for an equivalent product and subtracted from total project GHG emissions.
The calculation approach to be followed is set out below:
Procedure 4: Carbon mass balance if the co-product leads to crediting
Physical allocation based on carbon mass balance shall be used in instances where the co-product leads to crediting for CDR with Isometric, for example if the process produces both biochar and bio-oil. This is so that emissions are distributed according to the CO₂ balance output of the system. The requirement for crediting to be with an Isometric project ensures that co-product allocation can be traced and verified appropriately and according to the same set of allocation and emissions accounting requirements. The co-product allocation between CDR products can be made after process subdivision and substitution has taken place, however EC1 for subdivision is not viable where there is more than one CDR product.
The baseline scenario for biochar projects assumes that the activities associated with the biochar Project do not take place and that any infrastructure associated with the biochar Project is not built.
TheCounterfactual counterfactualstorage isassesses the CO₂ stored in the biomass feedstock2 that would have remained durablydurable stored inas thebiogenic biomasscarbon in the absence of theThe Project. This durably stored portion is called ineligible biomassfor increditing as it is not environmentally additional. The counterfactual storage of all feedstocks must be quantified according to the Biomass Feedstock Accounting Module v1.23. The Biomass Feedstock Accounting Module sets out requirements for establishing ineligible biomass as part of the Counterfactual Storage Eligibility criteria. The Biomass Feedstock Accounting Module includes details for quantification of [math: {CO}_{2}^{}e_{Counterfactual, RP}^{}].
See Section 3 of the Biomass Feedstock Accounting Module for requirements.
The Reporting Period, RP, for biochar projects represents anthe interval of time over which removals are calculated and reported for verification. The equations used to calculate net CO2e removals will pertain to all GHG emissions and CO2 removals occurring over a Reporting Period. In most cases, the Reporting Period willrepresents bea antimeframe intervalcovering a complete cycle of timeactivities, bounded by a batch ofincluding biomass feedstock sourcing, pyrolysis, biochar processing, and biochar storage activities, for example a spreading event.
For all storage pathways (A collection of Removal or Reduction processes that have mechanisms in common.) associated with biochar, it is necessary to calculate the total carbon content(as ofCO2e) stored in the biochar, ([math: C_{biochar}]). Guidelines for determining [math: C_{biochar}]. Guidelines for determining biochar carbon content are provided in Section 8.3.1. These calculations depend on methodologies outlined below,in the relevant Storage Module and shouldtherefore must be usedapplied in conjunction with the relevant storage Module calculations.
In addition to [math: C_{biochar}] quantification, upfrontan initial characterization is required to assessdetermine the amount of CO2 durably removed via the production ofthrough biochar and biochar durabilityproduction. The specific requirements and methodologies for this assessment are set outprovided in the relevant Biochar Storage in Agricultural Soils Module 1.1, Section 3).
GHG emission calculations must include all emissions related to the project activities that occur within the Reporting Period. This includes: (a) any emissions associated with project establishment allocated to the Reporting Period (See Section 8.56.1) (b) any emissions that occur within the Reporting Period (See Section 8.56.2), (c) any anticipated emissions that would occur after the Reporting Period that have been allocated to the Reporting Period (See Section 8.56.3) and (d) leakage emissions that occur outside of the system boundary that are associated with the Reporting Period (See Section 8.56.4).
Total net CO2e removal is calculated for each Reporting Period, and is written hereafter as [math: {CO}_{2}^{}e_{Removal, RP}^{}]. The final net CO2e removal quantification must be conservatively determined, giving high confidence that at a minimum, the estimated amount of CO2e was removed.
In line with the Isometric Standard, this Protocol requires that Removal Credits are issued ex-post (Issuance of Credits after removal or reduction took place. This is the manner in which Isometric Delivers Credits.). Credits may be issued once CO₂2 has been durably stored in the identified storage reservoir.
Net CO2e removal for the production of biochar and its durable storage for each Reporting Period, [math: RP], can be calculated by Equation 1.
[math: CO_2e_{Removal, RP} = CO_2e_{Stored, RP} - CO_2e_{Counterfactual, RP} - CO_2e_{Emissions, RP}]
(Equation 1)
Where:
Reversals (The escape of CO₂ to the atmosphere after it has been stored, and after a Credit has been Issued. A Reversal is classified as avoidable if a Project Proponent has influence or control over it and it likely could have been averted through application of reasonable risk mitigation measures. Any other Reversals will be classified as unavoidable.) which occur after Credits have been issued are separately accounted for by the Buffer Pool (A common and recognized insurance mechanism among Registries allowing Credits to be set aside (in this case by Isometric) to compensate for Reversals which may occur in the future.), and are therefore not included in Equation 1. Risk of reversal information is given in Appendix 1A: Risk of Reversal Questionnaire, with further information provided in Section 5 of the Biochar Storage in Agricultural Soils Module
The method of calculation for [math: CO_2e_{Stored, RP}] will depend on the method of storage. Refer to the relevant storage Module for requirements (see Section 1012).
[math:The C_{process of biochar}] production can be divided into several units from which Cbiochar can be calculated. forThese eitherare:
A ‘Production Batch’batch, [math: p], which typically consists of utilizing a single type of biomass feedstock, oftenor a consistent blend of amultiple singlefeedstocks. sourceThis ofis origin,subsequently converting the biomassconverted to biochar viathrough pyrolysis, and transporting that biochartransported to thea storage site for storage. The unique characteristics of the biomass used, the pyrolysis process, the produced biochar characteristics, transportation distances, and storage site characteristics will be the same for all of the biochar within a Production Batch. The processterm leading“Production Process” refers to the formationcomplete sequence of activities and operations that result in the creation of a '“Production Batch'”. The definition of a batch is project specific but must be a period of less than one month, even if the production process is consistent.
[math: C_{biochar}] can be calculated for either at the production batch or storage batch (i.e. a blend of biochar) level
Project Proponents must justify their intended approach for defining a production batch in the PDD.
[/R-6YSW-0]The two approaches are set out in the following sections:
Where biochar Production Batches are not blended prior to storage, is calculated as follows:
[math: CO_2e_{Stored,\ RP,\ p} = C_{biochar,\ p} \cdot m_{biochar,\ p} \cdot \frac{44.01}{12.01}]
(Equation 2)
Where:
The total amount of CO2 contained in the stored biochar can be calculated as follows.
Where all biochar Productionproduction Batchesbatches are blended prior to storage:
[math: CO_2e_{Stored,\n} = \frac{C_{biochar,\ n}\cdot m_{biochar, n}}{C_{CO_{2}}}]
(Equation 2)
Where biochar Production Batches are not blended prior to storage:
[math: CO_2e_{StoredRP,\ n} = \left(\sum_{p=1}^\text{kall } p \bigg(text{ in batch } n} \frac{C_{biochar,\ p} \cdot m_{biochar,\ p}}{C_{CO_{2100}}}\right) \bigg)times \frac{44.01}{12.01}]
(Equation 3)
Where:
The
This Protocol provides two alternative methods for themeasuring frequencyand with whichquantifying carbon content must be measured and quantifiedfrequency. TheMethod firstA methodrequires (A)measuring the carbon content of every production batch. Method B involves measuring every batch, the second method (B) involvessampling only samplinga arepresentative proportion of allproduction batches, and conservativelyapplying estimatingconservative estimates to determine the carbon content of unsampled batches.
Method A: Measure every Batch
Using this method
The Project Proponent must include all relevant details of unblendedtheir biocharsampling plan, including the Biochar originates from only a single Production Batch, by definition,number and nofrequency calculationof sampling and analysis and clear justification of their sampling choice, in the PPD document.
The preferred approach to sampling is required; or
For details regarding the acceptable minimum number of samples to be taken for each sampled Batch, see minimum number of samples per Batch below. If multiple samples are taken per Batch, the average [math: C_{biochar}] content of theseindependent samples must be used.collected Dataper useddefined production batch to calculatecharacterize variability within a production batch.
For example, if a project defines a production batch as a seven-day period, samples must be collected on three randomly selected days within that period, with each sample submitted to the laboratory as an independent field sample.
Any proposed alternative sampling approaches must be agreed with Isometric in advance.
For a given Production Process ofusing a specific feedstock, samples must be takencollected directly forfrom an agreed -upon number of initial Production Batches, tousing ensureMethod thereA (sampling every batch). This initial sampling is enoughrequired to generate sufficient data to estimate the carbon content forof future Production Batches with an appropriate level of statistical significanceconfidence. ThisThe shouldsample size must be agreeddetermined through consultation with Isometric, with a minimum requirement of 30 samples, for example three replicate samples from 10 batches. Until the time at which this threshold is reached, Method A must be used.
SubsequentlyUsing this method, the organic carbon content of a Production Batch must be determined through direct measurement, using one of the following approaches:
Refer to the section “Minimum Number of Samples per Batch” for requirements on the acceptable minimum number of samples per Production Batch.
Once Thethe initial required dataset has been established, routine sampling should continue with adequate sample archiving. Sampling should occur at the same frequency as Method A. However, at least once every 10 production batches, a set of ≥ 3 samples from a single batch must be submitted for analysis and quantification.
In exceptional cases, a different sampling Productionfrequency Batches can alternativelymay be agreed upon with Isometric prior to verification, provided that the productionProduction processProcess conditions can be provendemonstrated to beremain stable overthroughout the course of theThe Project.
For the acceptable minimum number of samples to take per Batch, see minimum number of samples per Batch below.
Alongside carbon, moisture is a key parameter used to calculate the mass of biochar stored and, therefore, the CO2e removed on a dry-mass basis. When Projects transition to Method B sampling, they must demonstrate one of the following:
[/R-ADXG-0]For batches which are not sampled, carbon content must be conservatively estimated, as follows:
[math: C_{Biochar} = \mu_{CC} - \sigma_{\overline{CC}}]
(Equation 4)
[math: \sigma_{\overline{CC}} = \frac{\sigma_{CC}}{\sqrt{n_{samples}}}]
(Equation 5)
Where:
Eligible samples are those taken in the previous 6 months before a specific Production Batch was produced. Older samples may not be used.
Additionally, batches must be subject to random sampling, to alleviate the risk of any given batch containing substantially different carbon contents.
A random sampling approach must be agreed upon with Isometric and documented in the Project Design Document, whereby Isometric will contact the Project Proponent on randomly selected days, at an agreed cadence, which must be no less frequent than once per month, on average. Once contacted, the Project Proponent must sample the carbon content of the subsequent batches processed.
If the Project Proponent is unable to carry this random sampling out on 3 occasions within a 6 month period, or if within a 6 month period more than 3 measurements are below 3 standard deviations from the mean, this will trigger a project review by Isometric.
If there is a significant change to a Production Process for a feedstock, which is likely to alter the average carbon content of the feedstock, or if significant deviations in carbon content are detected (as described below), the feedstock should be considered as a new Production Process. This means that sampling must be restarted, with all prior samples no longer able to be used for estimating carbon content.
Minimum number of samples per Batch
For all measurements taken, samplesSamples must be from a welldemonstrably mixedstable production process, evidenced by consistent production temperatures and representativeresidence aliquottimes or durations.
Process for handling carbon content measurement outliers
This process applies only ifwhen methodMethod B is used to calculate carbon content and shouldmust be applied to all carbon content measurements used whetherin athose batchcalculations, wasregardless of which production batches were sampled or not.
For a given Production Process, an Outlieroutlier is defined as any individual sample which lies more than 3 standard deviations, [math: \sigma_{CC}], above or below the mean. To minimize the potential overall impact of outlier measurements, all carbon content measurement outliers must be handled via applying the technique of "winsorization”, as follows.
For a given measurement, [math: m], thethat winsorizedlies measurementmore than three standard deviations ([math: m_w\sigma_{CC}]) isabove or below the mean ([math: \mu]):
[math: m > \mu + 3\sigma_{CC} \quad \text{or} \quad m < \mu - 3\sigma_{CC}]
To minimize the influence of extreme measurements, all outliers must be adjusted using winsorization, defined as follows:
WhereThe winsorized measurement [math: m_w] must then be used in all carbon content calculations.
Calculation of [math: \mu] and [math: \sigma_{CC}]:
TheWinsorization winsorized measurement, [math: m_w], must be used for the determination of carbon content.
This winsorization process mustmay only be applied onceafter a minimum number of 30 measurements have been taken,collected for the relevant production process to ensure statistical significance.
The Project Proponent must:
For all measurements, samples must be collected from a well-mixed and representative aliquot of the verifyingbiochar. VVBUnless otherwise agreed with Isometric, to account for potential variation within a single Production Batch, the following approach must be adopted:
Ensuring
Samples must accurately represent materials designated for the storage pathway that will form the basis for credit quantification. Biochar should be sampled in its final pre-storage condition, i.e., post-processing and at typical moisture levels. For storage in agricultural soils involving co-application with other substances (such as compost), sampling should occur before the blending process is performed.
The massmeasurement of biocharmass appliedstored will depend on the storage Module being used. As such, it is measuredfor viaThe determinationProject Proponent to describe and justify their stated method of weightmeasurement in the PDD. Below are examples of deliveredaccepted biocharmethods.
Preferred toMethod: theWeighbridge application site using a calibrated scale. This serves as proof of delivery to site for storage, as well as providing a weight measurement. Measurement
Anyunloaded truck scaleweights
Alternative Method: Documentation-Based Verification
In the event that
When using this alternative method, the deliveryPDD sitemust for storage. In this case, all details ofdetail:
The Project Proponent must maintain the following records as evidence of gross CO2e stored in applied biochar:
RecordsAll ofcarbon allanalysis C analysesresults and application massesmass records (e.g.including weigh scale tickets) must be maintainedretained by theThe Project Proponent for verification purposes for a periodminimum of at least five years.
Other
Biochar applicationproduction, transportation, and storage processes shouldmust be continuously monitored to ensureidentify thatand any processdocument:
Any deviations should be reported to Isometric as soon as reasonably possible after discovery.
When process upsets result in biochar loss:
This ensures that only successfully delivered and stored biochar is credited for carbon storage in The Project's GHG accounting.
Type: Counterfactual
[math: CO_2e_{Counterfactual,\ RP}] describes the CO2 that would have been removed from the atmosphere and stored beyond 15 years in the baseline scenario.
The calculation of [math: CO_2e_{Counterfactual,\ RPn}], is determined by the requirements outlined in Section 2 of the Biomass Feedstock Accounting Module v1.3.
See Section 3 of the Biomass Feedstock Accounting Module for calculation of [math: CO_2e_{Counterfactual,RP}].
Type: Emissions
[math: CO_2e_{Emissions,\ RP}] is the total quantity of GHG emissions from operations and allocated embodied emissions for each Reporting Period [math: RP]. This can be calculated as:
[math: CO_{2}e_{ Emissions,\ RP} = CO_{2}e_{Establishment,\ RP} + CO_{2}e_{Operations,\ RP} \\ + CO_{2}e_{End-of-life,\ RP} + CO_{2}e_{Leakage, RP}]
(Equation 6)
Where:
The following sections set out specific quantification requirements for each variable.
GHG emissions associated with [math: CO_{2}e_{Establishment,\ RP}] should include all historic emissions incurred as a result of project establishment, including but not limited to the SSRs set out in Table 1.
Project establishment emissions occur from the point of project inception through to before the first removal activity takes place. GHG emissions associated with project establishment may be allocated in one of the following ways, with the allocation method selected and justified by the Project Proponent in the PDD:
(The anticipatedterm lifetimeused to describe allocation of The Project should be based on reasonable justification and should be included in the PDD to be assessed as part of project validation.
Allocation of [math: CO_{2}e_{ Emissions,\ RP}] emissions to removalsmultiple mustRemovals beor reviewedReductions.) atare eachoutlined Creditingin PeriodSection renewal7 and any necessary adjustments made. Ifof the ProjectGHG ProponentAccounting isModule notv1.0.
See complySection with7 of the allocationGHG scheduleAccounting described in the PDD (e.g., due to changes in delivered volume or anticipated project lifetime), the Project Proponent should notify Isometric as early as possible in order to adjust the allocation schedule for future removals. If that is not possible, the Reversal process will be triggered in accordance with the Isometric Standard, to account for any remaining emissions.Module
GHG emissions associated with [math: CO_{2}e_{Operations,\ RP}] should include all emissions associated with operational activities including but not limited to the SSRs set out in Table 1. This includes direct emissions from pyrolysis, [math: CO_2e_{Direct, RP}], for which calculation and measurement details are set out in Section 910.21.1.
For biochar projects, the Reporting Period begins when the activity associated with a batch of Removals begins, and ends upon application of biochar from that batch at the storage site. As an example, for Projects storing biochar in agricultural soils, the Reporting Period begins with biomass feedstock sourcing and ends with biochar application to agricultural soils. The Reporting Period may cover a set period of time, for example a one month period of activity, inclusive of biomass sourcing through to application on agricultural soils for batches of Removals that fall into that month.
[math: CO_{2}e_{Operations,\ RP}] emissions must be attributed to the Reporting Period in which they occur. Allocation may be permitted in certain instances, on a case by case basis, in agreement with Isometric.
[math: CO_{2}e_{End-of-life,\ RP}] includes all emissions associated with activities that are anticipated to occur after the Reporting Period, but are directly or indirectly related to the Reporting Period. For example this could include end-of-life emissions for project facilities (indirectly related to all deployments).
GHG emissions associated with [math: CO_{2}e_{End-of-life,\ RP}] may occur from the end of the Reporting Period onward, and typically through to completion of project site deconstruction and any other end-of-life activities.
GHG emissions associated with activities that are directly related to each deployment must be quantified as part of that Reporting Period. GHG emissions associated with activities that are indirectly related to all deployments may be allocated in the same ways as set out in [math: CO_{2}e_{End-of-life,\ RP}].
Given the uncertain nature of [math: CO_{2}e_{End-of-life,\ RP}] emissions, assumptions must be revisited at each Crediting Period and any necessary adjustments made. Furthermore, if there are unexpected [math: CO_{2}e_{End-of-life,\ RP}] emissions associated with a Reporting Period, or The Project as a whole, that occur after The Project has ended, then the Reversal process will be triggered to compensate for any emissions not accounted for.
[math: CO_{2}e_{Leakage,\ RP}] includes emissions associated with a Project's impact on activities that fall outside of the system boundary of a Project.
It includes increases in GHG emissions as a result of The Project displacing emissions or causing a knock on effect that increases emissions elsewhere. This includes emissions associated with activity-shifting, market leakage and ecological leakage.
It is theThe Project Proponent's responsibility to identify potential sources of leakage emissions. At a minimum, biochar Projects must account for market leakage emissions associated with biomass feedstocks as set out in accordance with the Biomass Feedstock Accounting Module v1.23.
[math: CO_{2}e_{Leakage,\ RP}] emissions must be attributed to the Reporting Period in which they occur. Allocation may be permitted in certain instances, on a case by case basis in agreement with Isometric.
See EmissionsSection AccountingThis section4ProtocolBiomass outlinesFeedstock requirementsAccounting forModule
GHG emissions accounting relatingmust be undertaken in alignment with the GHG Accounting Module v1.0, which ensures a consistently rigorous standard in how GHG emissions are quantified and reported between different CDR Projects and approaches.
Project Proponents must use the most representative, accurate and plausible data that is available at the time of assessment in the GHG Statement. Activity data used to energyinform GHG accounting may be primary data or secondary data. Project Proponents must strive to use primary data in GHG accounting, transportationbut secondary data may be used where primary data is either not available or not practical. More details on data requirements, including data quality hierarchy and data quality principles, can be found in Section 3 of the GHG Accounting Module v1.0.
See Section 3 of the GHG Accounting Module
An example is emissions related to building the pyrolysys reactor. The Project Proponent should strive to obtain activity data such as mass and type of materials used for the reactor, as well as distanced travelled to transport the materials, and embodiedenergy used during the construction process. If such data is not available, it is acceptable to use an industry average data and emission factors to estimate such emissions. Suitable emission factor sources are described in relevant Modules.
Embodied emissions associated with system inputs considered to be waste products (An output of a Projectprocess that has no intended value to the producer.) can be excluded from the accounting of the GHG Statement system boundary provided the appropriate eligibility criteria are met.
For waste energy inputs, for example the use of waste heat, refer to the Energy Use Accounting Module v1.62.1
Refer to Energy Use Accounting Module for the calculation guidelines.
All biomass feedstock must be eligible and accounted for according to the Biomass Feedstock Accounting Module v1.3.
See Biomass Feedstock Accounting Module for eligibility criteria.
For all other waste inputs, refer to Section 6.3 of the GHG Accounting Module v1.0.
See GHG Accounting Module for eligibility criteria.
The biomass pyrolysis process may result in the production of co-products, such as bio-oil, pyrolysis gas (bio-gas), electricity and heat.
Projects must follow the co-product allocation procedures described in Section 6.1 of the GHG Accounting Module v1.0. For projects where the CDR product(s) and co-products have a measurable energy content, the optional procedure outlined in Section 8.6.5.2.1 may be applied instead of the Procedures outlined in Section 6.1 of the GHG Accounting Module v1.0.
Emissions allocation may be undertaken based on energy content for shared processes in instances where all co-products, including CDR products, have a measurable energy content which can be expressed in Megajoules (MJ). Shared processes are defined as processes for which the CDR product and all co-products are mutually dependent on. Where this is not the case for all co-products, no allocation should be made based on energy content. In this section Net Calorific Value is defined as the amount of energy released by complete combustion, assuming the water vapor produced during combustion is not condensed and used.
Equation 7 sets out the calculation procedure to be followed to apply emissions allocation based on energy content. When this procedure is followed, the term [math: CO_2e_{Emissions,RP}] in Equation 6 in Section 8.6 should be calculated based on Equation 7 for shared processes.
[math: CO_2e_{Emissions,RP} = (F_{Allocation,RP} \;*\; ( CO_2e_{Establishment,RP} \;+ \;CO_2e_{Operations,RP} \;+ \;CO_2e_{End-Of-Life,RP})) \;+ \;CO_2e_{Leakage,RP}]
(Equation 7)
Where:
[math: CO_2e_{Establishment,RP}], [math: CO_2e_{Operations,RP}], [math: CO_2e_{End-Of-Life,RP}] and [math: CO_2e_{Leakage,RP}] are calculated as per the relevant sections of this Protocol.
[math: F_{Allocation}] is the fraction of emissions assigned to the CDR product, represented as:
[math: F_{Allocation} = \frac {MJ_{Output, CDR}}{\qquad \sum_{p=1}^n MJ_{Output, p}}]
(Equation 8)
Where:
[math: MJ_{Output, CDR}] is the energy content of the CDR product, equal to the Net Calorific Value, expressed in MJ/kg.
[math: MJ_{Output}] is the energy content of a specific output, expressed in MJ. The sum of outputs for all co-products must be considered in Equation 8:
This section sets out specific requirements relating to quantification of energy use as part of the GHG Statement. Emissions associated with energy usage result from the consumption of electricity or fuel.
Examples of electricity usage may include, but are not limited to:
Examples of fuel consumption may include, but are not limited to:
The Energy Use Accounting Module v1.2 provides requirements on how energy-related emissions must be calculated in a CDR Project. It sets out the calculation approach to be followed and acceptable emissions factors.
Refer to Energy Use Accounting Module for the calculation guidelines.
This section sets out specific requirements relating to quantification of emissions related to transportation.
Emissions associated with transportation include transportation of products and equipment as part of a Reporting Period process. Examples may include, but are not limited to:
The Transportation Emissions Accounting Module v1.1 provides requirements on how transportation-related emissions must be calculated in a CDR Project so that they can be subtracted in the net CO2e removal calculation. It sets out the calculation approach to be followed and acceptable emissions factors.
Refer to Transportation Emissions Accounting Module for the calculation guidelines.
This section sets out specific requirements relating to quantification of embodied emissions (Life cycle GHG emissions associated with production of materials, transportation, and construction or other processes for goods or buildings.) as part of the GHG Statement. Embodied emissions are those related to the life cycle impact of equipment and consumables.
Examples of project-specific materials and equipment that must be considered as part of the embodied emission calculation include but are not limited to:
The Embodied EmissionsGHG Accounting Module v1.0 sets out the calculation approach to be followed includingto allocationaccount offor embodied emissionsemission, including life cycle stages to be considered (Section 4.1), data sources and emission factors (Section 3.
Referrules on amortization (The term used to Embodieddescribe Emissionsallocation Accountingof ModuleProject foremissions theto calculationmultiple guidelinesRemovals or Reductions.) (Section 7).
Pyrolysis is the process of thermochemical conversion of a solid biomass feedstock. The biomass is heated to a temperature greater than 300°C without addition of an oxidizing atmosphere. Pyrolysis of biomass results in a product mixture containing solid biochar, liquid bio-oil, and gasses.
There are a wide range of technologies available for achieving pyrolysis of solid biomass,. whichThese can generallymay be categorizedcharacterized into "slow pyrolysis" and "fast pyrolysis" based on the heating rate and residence time of biomass in the pyrolysis chamber. Slow pyrolysis processes are ideal to maximize the yield of pyrolysis towards the solid biochar product, and minimize the production of bio-oil and pyrolysis gasses, however both "slow" and "fast" pyrolysis processes may be eligible under this Protocol. SeveralTechnology may also be characterized by its technology level (low- mid or high- technology) based on the reactor configurationsdesign, canas well as the level of automation, and application of sensors and monitoring equipment. Equally, processes may be usedeither tocontinuous achieve(ongoing slowwith pyrolysisa regular flow of biomassfeedstock tothrough producethe biocharsystem), including bothor batch reactors(non-continuous) andbased.
This semi-batchProtocol reactorsdoes (e.g.not fixed-beds,explicitly fluidized-beds,specify etc.). Anythe type of reactor configurationor istechnology eligiblelevel under this Protocolrequired, providedProject thatProponents must be able to meet the reactor designmonitoring requirements set out in Section 9.1 below are satisfied. A brief overview of common reactor configurations covered under this Protocol are provided in the Table 5 below. However, novel reactor configurations not belonging to any of the categories listed here will be acceptable provided that the appropriate reactor design documentation according to Section 9.1 is supplied in the PDD. Alland reactor designs, including the reactor type, expected materials specifications and engineering design diagrams and materials selection must be described in the PDD.
Biochar can be produced using a wide range of technologies that vary in scale, level of automation, and intended outputs. Some reactor systems are specifically designed to produce biochar as the primary product of the process. These tend to be more centralized, higher-technology solutions that allow for precise control of operating parameters such as temperature, residence time, and oxygen levels, resulting in consistent product quality and higher levels of process monitoring. A summary of common reactor types is found in Table 5.
Table 5: Overview of common reactor types
Reactor type | Description |
|---|---|
Fixed-bed reactor | Solid biomass is loaded into a vessel. Heat is applied to the vessel to increase the temperature of the biomass. Once the target pyrolysis temperature is reached, and potentially sustained for some period of time, the solid biochar product is collected in a batch-mode. Gaseous and solid products self-separate within the reactor. |
Auger reactor | Solid biomass is continuously fed to and transported through a cylindrical vessel using a screw-type fitting. Heat is applied to the exterior of the vessel. As biomass is transported along the length of the reactor, its temperature is increased. The target pyrolysis temperature is reached at the product exit point from the reactor. Gaseous and solid products are collected and separated at the reactor outlet. The biochar product is collected continuously. |
Rotary kiln reactor | Solid biomass is continuously loaded at the top of an inclined rotating drum. As more biomass is added to the vessel, biomass inside the vessel is transported downwards. Heat is applied to the exterior of the vessel. As biomass is transported along the length of the reactor, its temperature is increased. The target pyrolysis temperature is reached at the product exit point from the reactor. Gaseous and solid products self-separate at the reactor outlet. The biochar product is collected continuously. |
MaximumThis pyrolysisProtocol temperaturerecognizes the diversity of production approaches and establishes performance-based requirements to ensure that, regardless of technology type or scale, environmental safeguards, product quality, and monitoring standards are maintained.
Additional styles of project may bealso manipulatedinclude:
Refers to the Biochar Production in orderDistributed and Small Scale Projects for the additional MRV requirements.
Refers to increasethe Biochar Production in Combustion Co-product Systems for the yieldadditional ofMRV solid biochar products and their relative carbon stability. For example, pyrolysis at higher temperatures may lower the yield of the solid biochar. However, thermal breakdown of biochar is positively correlated with increasing temperatures - yielding biochar with lower volatile content that is more stable. The optimum range for pyrolysis temperature is 500–800°C to maximise the production of highly stable biochar7requirements.
An(P&ID) or engineering design diagram of the chemical reactor. usedThe todiagram achievemust include all measurement sensors (e.g. temperature, pressure, flow) with labels identifying sensor type and location]
An engineering design diagram of the Project pyrolysis reactor design(s) must be included in the PDD.
The design diagram must includeclearly detailsshow:
The listeddiagram abovemust include sufficient viewpoints to illustrate the placement of all key components.
Additionally, any other process equipment essential for the safe and effective operation of the pyrolyzer should also be included and clearly highlighted.
[/G-8RAM-1]In instances where Project Proponents wish to expand an existing Project, or to submit a new Project for validation, where the reactor vessels used to achieve pyrolysis of biomass are manufactured according to the same design diagrams as those submitted for initial project validation, it is not necessary to resubmit a new design diagram at each subsequent validation event. In cases where the design of the reactor vessel differs to that from the original project validation, submission of updated design diagram documentation is required.
The reactor design must include sensors to quantify leakage due to loss of pyrolysis gasses during operation of the reactor. This should include, at minimum, sensors to determine the outflow of pyrolysis gasses from the flue gas outlet, which can be used in conjunction with a suitable reactor model to determine the amount of pyrolysis gasses produced and to estimate any loss of these gasses by unmonitored and unintentional leakage to the environment. The chemical reactor model used to characterize reactor performance and estimate pyrolysis gas losses should consider all physical and chemical mechanisms relevant to the operation of the chosen reactor type. The chemical reactor model should incorporate a chemical kinetics model which is based on the latest scientific understanding for the chosen reactor configuration. The model should be demonstrated to be validated using empirical data and should include a process mass balance accounting for the product yields. Details of the validation of the chemical reactor model should be provided in the PDD.
Alternatively, in situations where it is not possible to develop a high-quality mathematical reactor model to represent pyrolyzer operations, it is permissible to deploy one of the following alternative approaches to verify that there is no substantial unintended leakage of gaseous products from the system:
It is anticipated that the operation of the pyrolyzer will occuroperate at high temperature,temperatures and may occuralso operate at elevated pressurepressures. AppropriateTherefore, appropriate design considerations needmust be implemented to be made inensure the designmechanical integrity and safe operation of the reactor to mitigate potential adverse operational conditions.
The PDD must include detailed information on the selection of materials used for each reactor component, along with a justification of these choices from the perspectives of thermal and mechanical resilience.
[/R-DMET-0]For reactors operating at high pressure (>0.5 Bar above ambient pressure), the design must address:
These considerations are essential to ensure the mechanical integrity and safe operation of the reactionreactor.
All design measures must comply with an appropriate local standard ingoverning the regiondesign and fabrication of projectpressure operationvessels, such as 2014/68/EU (the Pressure Equipment Directive) or an equivalent regional standard applicable to The Project’s location.
If no suitable regional standard exists, Project Proponents are required to follow the 2014/68/EU standard.
[/G-5EFD-1]An appropriate reactor maintenance plan should be in place, and must be detailedestablished and fully documented in the PDD.
The PDD should outlinedescribe how theThe Project Proponent will ensure the structural integrity of the reactor vessel in order to mitigate againstprevent potential material loss events., Thisincluding:
If applicable, all maintenance activities must comply with an applicable local standard governing the inspection and maintenance of projectpressure operationvessels, such as 2014/68/EU (the Pressure Equipment Directive) or an equivalent regional standard relevant to The Project’s location. If no such regional standard exists, the 2014/68/EU standard must be applied.
This section sets out the permissible ultimate fate of requirements for the measurement and quantification of gaseous pyrolysis gas loss from the reactor and the calculation of the direct carbon emissions from pyrolysis.
Project Proponents must evidence emissions monitoring by either regular emissions testing or direct continuous measurement.
[/R-TKNH-0]The thermochemical conversion of solid biomass to produce biochar in athrough pyrolysis process also produces a gas as a significantgaseous co-productproducts. TheDepending gason containsthe pyrolysis conditions and feedstock, the gaseous phase may contain both volatile condensable components (bio-oil) and non-condensable components (pyrolysis gasses; predominantly CH4, with HN2O, CO, CO₂2 and light hydrocarbons). Depending on the specific technologies deployed by theThe Project, there are various options for handling the gaseous co-product eluted from the pyrolyzerpyrolysis unit. Permissible options for the measurement and handling the gaseous product and emissions accounting requirements associated requirements are detailed in this sectionSection.
TheN2O gasses eluted from the pyrolyzer are fed tois a condenserpotent greenhouse gas, orwhich anymay otherbe suitableformed gas-liquidduring separation unit, to separate the condensable and non-condensable fractionspyrolysis of thefeedstocks gaseouswith productlow C/N ratios. The resultingpresence (condensable)of liquid-phasesubstantial reactive or labile N is bio-oil,a andkey precursor to N2O formation in the (non-condensable)flue gas-phase. While there is pyrolysisno gasses.accepted Therethreshold arein threethe permissiblescientific end-useliterature below which N2O emissions accountingfrom approachesflue forgas thebecomes produceda bio-oil:
There are four permissible end-use emissions accounting approaches for the produced pyrolysis gasses:
Project Proponents must secure and compositionmaintain ofall therequired ventedpermits gasand streamapprovals related to determine theair emissions associated with the vented gasses. Composition measurements must account for at least CH4, H2,combustion COequipment, and CO2other applicable air quality regulations for biochar production.
This gassessection withindetails the projecttwo gateacceptable to provide thermal energy for operationmethods of the pyrolyzer. The Project Proponent must measurequantifying the flowDirect rate and composition of the flue gas eluted from the heating source for the pyrolyzer. Composition measurements must account for at least CH4, H2, CO, and CO2. It should be noted that the flue gas from the pyrolyzer heating source may also partially result from co-firing with fuels obtained from outside sources. If the flue gas from the pyrolyzer heating source is directly monitored, it is not necessary to include fuel combustion for heating the pyrolyzer in the calculation ofEmissions [math: CO_{2}e_{EnergyOperations,\ RP}], to avoid double counting. However, the emissions associated with the production and transportation of such fuels must still be accounted for. Bio-oil produced during pyrolysis may also be co-fired using this approach, and can be accounted for in the same way as for the co-firing of pyrolysis gasses.
All non-CO2 emissions to the atmosphere, via any of the approaches described above, must be converted to tonnes of CO2e using the 100-year Global Warming Potential (GWP) for the relevant GHGs, based on the most recent volume of the IPCC Assessment Report (presently the Sixth Assessment Report).
Direct emissions from a pyrolysis process, occureither whenthrough pyrolysisdirect gassescontinuous aremeasurement emittedor toregular emissions testing.
Direct measurement is the atmosphere,primary areand combustedpreferred in an emissions control unit, or are combusted within the processmethod for thequantifying provision[math: ofCO_{2}e_{Operations,\ thermal energy for the processRP}]. Direct emissions
Emissions should be calculated as follows:
[math:CO_2e_CO_{Direct2}e_{Operations,\ RP} = \sum_{n=1}^{n_c} \sum_{i=1}^{N} m_{i} \cdot C_{n,i} \cdot GWP_n \cdot \Delta t_i]
(Equation 79)
Where:
Note: Direct CO2eemissions emissions,reported [math:under CO_2e_{Direct,this RP}],section considerinclude non-CO2 greenhouse gases only, as CO2 emissions onlyare accounted for separately to avoid double counting, given that release of. CO2 emissionsreleased during pyrolysis willis be realizedreflected in thereductions reductionto ofstored carbon stored in the biochar after pyrolysis of biomass. Carbon stored is calculated as ([math: CO_2e_CO_{Stored2eStored, RP}]), which directly informsdetermines net CO2e removal and Crediting. Consideration of non-CO2 emissions during pyrolysis is important given the amount and composition of gasses emitted during pyrolysis may be substantially different to that emitted in the baseline scenario, for example as a result of biomass decay or combustioncrediting.
Quantification of [math: CO_2e_CO_{Direct2}e_{Operations,\ RP}] requires two primary measurements,:
Gas flow rate, [math: m_i], must be:
The concentration of CH4, H2, CO, and CO2 must be:
Where direct measurement is not practically feasible (e.g., highly distributed pyrolysis reactors, remote locations), emissions testing may be used as an alternative method. This measurement will then be applied to all subsequent batches produced, until the next emissions test is performed (with the exception of distributed project, see Section 9.1.1.4).
Emissions should be calculated as follows:
[math: CO_{2}e_{Operations,\ RP} = \sum_{n=1}^{n} (C_{n,test} \cdot \dot{m}_{test} \cdot GWP_n \cdot H_{emit})]
(Equation 10)
Where:
For some projects, particularly those deploying pyrolyzers in a highly distributed manner or in remote locations, the measurementtonnes of directCO2e, emissions to the atmospheremeasured using calibrated gas flow and concentration sensors may not be a practically feasible approach. As an alternative to the measurement requirements established in Section 9.2.2,regular emissions testing data may be used to estimate [math: m_i] and .
The gas flow rate(dry/wet, standard temperature and pressure).
Note: Direct emissions testingreported inunder conjunctionthis withsection measurementsinclude of the pressure drop in the direct emission stream. The concentration of CH4, Hnon-CO2 greenhouse gases only, CO, andas CO2 shouldemissions beare determinedaccounted usingfor concentrationseparately datato fromavoid double counting. CO2 released during pyrolysis is reflected in reductions to stored carbon ([math: CO_{2eStored,RP}]), which determines net CO2e removal and crediting.
Emissions testing data shouldmust be producedconducted by a qualified emissions testing company,an accredited toprovider the Stack Testing Accreditation Council for(e.g., ASTM D7036, ISO 17025, or approved by state regulatoryor regional authority). toThese performtests compliance emissions testing.
For emissions testing tomust be consideredperformed at least annually on all reactors/kilns being used by The Project.
Regular Emissions Testing should be representative of actual project operations, theincluding followingquenching criteriaif mustappropriate. beEmissions satisfiedtesting is considered representative only if:
MeasurementTemperature of the temperature within the flue stack shouldmust be conductedmeasured using a calibrated sensor whichthat satisfies the below requirementsis:
Raw data must be retained and made available on request.
The Project Proponent must retain for at least five years:
All non-CO2 emissions to the atmosphere, via any of the approaches described in the following Sections, must be converted to tonnes of CO2e using their respective 100-year Global Warming Potential (GWP) for the relevant GHGs, based on the most recent volume of the IPCC Assessment Report (presently the Sixth Assessment Report).
Project Proponents must confirm which of the four permissible end-use emissions accounting approaches for the produced pyrolysis gasses they plan to use.
[/R-E8H6-0]These are:
If the reactor operates at above atmospheric pressure, the reactor design must incorporate appropriate sensors and monitoring systems to detect and quantify any loss of pyrolysis gases during operation.
[/R-SZK5-1]At a minimum, the system must include:
A chemical reactor model may be used to characterize reactor performance and estimate gas losses, and must:
If it is not feasible to develop a high-quality mathematical reactor model, one of the following alternative verification approaches may be used to demonstrate that there is no substantial unintended leakage of pyrolysis gases:
Condensable fractions of the gaseous stream may be separated from the using a condenser, or any other suitable gas-liquid separation unit. The resulting (condensable) liquid-phase is bio-oil, and the (non-condensable) gas-phase is pyrolysis gasses. There are three permissible end-use emissions testing
accounting approaches for the produced bio-oil:
For all information on what chemical and physical characterization of biochar must be carried out, and for calculation of [math: {CO}_{2}^{}e_{Stored}^{}], please refer to the relevant storage Module.
Durability and monitoring requirements for Biochar Storage in AgriculturalSoils SoilsEnvironments.
Durability and monitoring requirements for Biochar Storage in Low Oyxgen Burial Environments.
Durability Appendixand 1:monitoring Riskrequirements offor ReversalBiochar Questionnaire
This risk assessment identifies the pathway specific risk factors relevant to a carbon removal project. The relevant risk factors identified as part of a risk assessment are includedStorage in the monitoringBuilt plan requirements for the project, with details included in the Project Design Document. Project specific risk factors inform the required duration of monitoring along with the monitoring requirements set out in the Protocol and the requirements set out in the Monitoring Section of the Isometric StandardEnvironment.
The risk score, as determined by the Risk of Reversal Questionnaire, will determine a project’s buffer pool contribution. Projects must re-assess their reversal risk at the renewal of each crediting period, or if monitoring identifies a reversal-related risk, or if an actual reversal event takes place. In any event, projects should reassess their reversal risk at a minimum every 5 years.
The Risk of Reversal Questionnaire questions that pertain to this protocol, drawn from the programme-level Risk of Reversal Questionnaire defined in Appendix B: Risk Reversal Questionnaire of the Isometric Standard, include the following:
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Risk Score Categories
Project specific risk factors will depend on the form of carbon being stored (i.e., organic vs. inorganic), the method of storage (e.g., mineralization, encapsulation), the location of carbon storage (e.g., subsurface, ocean), and the proximity of that carbon to potential agents of reversal.
For projects with carbon storage as organic carbon, the presence of the following risk factors must be reflected in the risk score corresponding to question 10:
For projects with any form of subsurface carbon storage, the presence of the following risk factors must be reflected in the risk score corresponding to question 10:
Isometric would like to thank the following contributorsexternal toreviewers of this Protocol:
Isometric would like to thank following contributors to this Protocol/Module:
This risk assessment identifies the pathway specific risk factors relevant to a carbon removal project. The relevant risk factors identified as part of a risk assessment are included in the monitoring plan requirements for The Project, with details included in the PDD. Project specific risk factors inform the required duration of monitoring along with the monitoring requirements set out in the Protocol and the requirements set out in the Monitoring Section of the Isometric Standard.
The risk score, as determined by the Risk of Reversal Questionnaire, will determine a project’s buffer pool contribution. Projects must re-assess their reversal risk at the renewal of each crediting period, or if monitoring identifies a reversal-related risk, or if an actual reversal event takes place. In any event, projects should reassess their reversal risk at a minimum every 5 years.
The Risk of Reversal Questionnaire questions that pertain to this Protocol, drawn from the programme-level Risk of Reversal Questionnaire defined in Appendix B: Risk Reversal Questionnaire of the Isometric Standard, include the following:
# in Isometric Standard Questionnaire | Question | If answered “Yes” | If answered “No” |
|---|---|---|---|
1 | Is a reversal directly observable with a physical or chemical measurement as opposed to a modeled result? | Proceed to questions 2-9 | Proceed to questions 8-9 |
2 | Is the carbon being stored in an impermeable geologic system? (e.g., salt cavern) | Proceed to questions 8-9 | Add 1 to Risk Score and proceed to questions 3-9 |
3 | Is the carbon being stored organic? | Add 1 to Risk Score | |
5 | Does this approach have a material risk of reversal due to natural disasters including, but not limited to, floods, storms, earthquakes, fires, etc.? | Add 1 to Risk Score | |
6 | Does this approach have a material risk of reversal due to human-induced events from outside actors, such as change in farming practices, change in ownership and management of project sites, or similar? | Add up to 2 to Risk Score | |
8 | Is there 10+ years of monitoring and/or lab data demonstrating low project risk? | Minus up to 2 to Risk Score | |
9 | Does this pathway have a documented history of reversals? | Add 2 to Risk Score | |
10 | Is there one or more project-specific factors that merit a high risk level? | Add up to 2 to Risk Score |
Risk Score Categories
Project specific risk factors will depend on the form of carbon being stored (i.e., organic vs. inorganic), the method of storage (e.g., mineralization, encapsulation), the location of carbon storage (e.g., subsurface, ocean), and the proximity of that carbon to potential agents of reversal.
For projects with carbon storage as organic carbon, the presence of the following risk factors must be reflected in the risk score corresponding to question 10:
For projects with any form of subsurface carbon storage, the presence of the following risk factors must be reflected in the risk score corresponding to question 10:
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