This Protocol provides the requirements and procedures for the calculation of net CO2 equivalent (CO2e)removals from the atmosphere via Industrial Process Biogenic Carbon Capture and Storage (Bio-CCS). This Protocol is developed for application to Bio-CCS processes or combinations of processes (e.g., solid sorption,1 liquid solvent,2 membrane processes,3 electrochemistry,4 etc.) in which a cradle-to-graveGHG Statement can be accurately applied and in which the CO2 captured is stored via physical5 or chemical6 trapping mechanisms for > 1000 years.
The Protocol ensures:
Specific standards and protocolsProtocols which are utilized as the foundation of this Protocol and for which this Protocol is intended to be fully compliant with are as follows:
Additional reference standards that inform the requirements and overall practices incorporated in this Protocol include:
This Protocol was developed based on the current state of the art and publicly available science regarding Bio-CCS.7,8,9. As Bio-CCS is still a developing approach to carbon dioxide removal (CDR) with ever-expanding published literature, this Protocol incorporates requirements that may be more stringent than other available regulations or Protocols. The approach taken here may be altered in future versions of the Protocol in-line with advancements in the available technology and published research.
This Protocol applies to projects anywhere that capture biogenic carbonCO2 at a point-source, resulting from processing of an eligible biomass feedstock as outlined in the Biomass Feedstock Accounting Module v1.3, and store this carbonCO2 with >1000 years durability via physical or chemical trapping mechanisms laid out in a relevant CO2 Storage Module (see Section 89). Projects that capture CO2 that is notExamples of biogenicapplicable originpoint-sources include, but are not eligiblelimited to, biomass-fired power plants, biomass-fired combined heat and power (CHP) facilities, bio-hydrogen production, biogas plants, and Energy-from-Waste (EFW) facilities.
Projects which utilise waste feedstocks where biogenic and fossil carbon is inseparable are only eligible if:
Projects which utilise waste feedstocks where biogenic and fossil carbon is inseparable must demonstrate that there is a robust waste management hierarchy that ensures only unrecyclable waste is incinerated.
[/R-Q8V2-0]See Section 2 of Biomass Feedstock Accounting Module v1.3 for eligibility criteria.
Projects which co-fire biomass with fossil fuels, or those using waste feedstocks where biogenic and fossil carbon is inseparable, must use an emission factor for the used mass of fossil fuels that accounts for the full upstream and combustion emissions.
If the fossil CO2 is captured alongside the biogenic carbon, quantified according to the requirements in Section 8.2.1.1, and (barring unavoidable CO2 leaks) is transported to the same storage reservoir as the biogenic CO2, then Projects may use an emission factor for the fossil fuel which considers only the upstream emissions and excludes combustion emissions.
[/R-AXPQ-0]Whether emitted fossil CO2 is considered a Project emission is dependent on the baseline scenario according to the guidelines in Section 7: System Boundary and Project Baseline, Appendix A: Guidance for Handling Fossil CO2 and Appendix B: Baselines.
Additionally, Projects where more than 5% of feedstocks by mass are fossil fuels must provide a justification for the necessity of these feedstocks within the context of the carbon dioxide removal (CDR) Project at validation if applicable to the whole Project lifetime, or at verification if related to a specific Crediting Period only, subject to agreement with Isometric. Isometric reserves the right to not Credit Removals attributed to a given Reporting Period of a Project that has violated this guardrail without appropriate justification.
[/R-YJJC-0]The Project Proponent must consider environmental and social impacts andfrom processes that comprise part of the Project. The Project Proponent must provide evidence that Thethe Project will do no net environmental or social harm by complying with Section 3.7 of the Isometric Standard as well as the following requirements:
Certain waste feedstocks may carry a higher risk of pollution due to contamination with hazardous components, such as chemical solvents or trace metals. The incineration of municipal solid waste (MSW) can also carry a higher risk of pollution because heterogeneous feedstocks vary in composition and may contain trace contaminants. As a result, proper handling of waste and by-product outputs is essential.
Projects involving the combustion of such materials must demonstrate that the facility complies with all relevant national, regional, and local environmental regulations for responsible waste handling, such as the EU Waste Incineration Directive (WID) and the Industrial Emissions Directive (IED), or an equivalent standard applicable to the Project's location.
If no suitable regional standard exists, Project Proponents are required to demonstrate that the facility follows international best practice frameworks for pollution management, including appropriate treatment of the following waste streams:
[/R-5W9P-0]Typically the largest fraction of the output mass, bottom ash is typically composed of mineral residues, metals and potentially some small amount of uncombusted organic matter. Separation of the metals and suitable treatment to enable recycling/reuse is recommended. Project Proponents must establish an end-use/disposal of the ash, such as: recycling (separation of ferrous and non-ferrous metals); and/or treatment of the ash to enable reuse as Incinerator Bottom Ash Aggregate (IBAA) in construction. If bottom ash is sent to landfill as non-hazardous waste, Project Proponents must provide justification that there is no risk of hazardous leaching (for example, through EN 12457-2 or EN 14405 testing).
[/G-GH82-0]Fly ash typically comprises up to 5% of the original feedstock mass, consisting of fine particles captured from the flue gas, often with high concentrations of heavy metals, dioxins and furans. Both waste residues are considered hazardous waste. As such, Project Proponents must propose an appropriate method of disposal, for example by sending to a hazardous waste facility, or taking additional steps to stabilize the fly ash, using physical or chemical binders.
[/G-463Q-0]Project Proponents must use best available techniques to monitor and reduce flue gas emissions in compliance with the EU Industrial Emissions Directive (IED) and the limits detailed in EU Directive 2010/75/EU Annex VI Part 3, or equivalent local legislation.
[/G-QTZC-0]Persistent Organic Pollutants (POPs), such as dioxins and furans, may be present in mixed waste material. If released to the environment, POPs can accumulate in living organisms and pose risks to human health and ecosystems. The high combustion temperature of incineration facilities leads to the destruction of POPs.
To reduce the prevalence of POPs, the flue gas must have a residence time of at least two seconds at homogeneous temperatures > 850 °C in the post-combustion zone. Temperature data must be reported alongside other data during a verification.
[/G-BFV1-0]In addition, Project Proponents must propose a method for monitoring halogen content in any feedstock containing both fossil and biogenic carbon. Should the halogen content determination result in > 1%, the flue gas must have a residence time of at least two seconds at homogeneous temperatures > 1100 °C in the post-combustion zone instead.
[/G-Z4PP-0]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 Project 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 Verificationverification and evaluation in accordance with this Protocol, and must include consideration of processes unique to Bio-CCS, for example:
Projects must be validated and project net CO2e removals verified by an independent third party consistent with the requirements described in this Protocol as well as in Section 4 of the Isometric Standard.
The Validation and Verification Body (VVB) must consider following requisite components:
The threshold for Materiality, considering the totality of all omissions, errors and mis-statements, is 5%, in accordance with Section 4.3 of the Isometric Standard.
Verifiers should also verify the documentation of uncertainty 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:12
Project validationValidation and verificationVerification must incorporate site visits to project facilities in accordance with the requirements of ISO 14064-3, 6.1.4.2, including, at minimum, site visits during validationthe andfirst initialValidation verificationor Verification of a Project, to the capture and (if applicable) storage site. Verifiers should whenever possible observe operation of the capture and storage processes to ensure full documentation of process inputs and outputs through visual observation and validation of instrumentation, measurements, and required data quality measures.
A site visit must thereafter occur at least once every 2 years atduring each locationProject 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.
VVBs must comply with the requirements defined in Section 4 of the Isometric Standard. In addition, teams should maintain and demonstrate expertise associated with the specific technologies of interest, including solvent/sorbent chemistry, electricity procurement and heat/power generation and the relevant CO2 storage technology.
Competency must be demonstrated in accordance with Isometric's VVB policy, for example throughbased on the relevant sectoral scope accreditations in IAF MD 14, or another demonstration of relevant expertise for this Protocol and the selected storage module(s).
CDR via Bio-CCS and subsequent storage is often a result of a multi-step process (such as capture, desorption, CO2 transport, CO2 temporary holding, the CO2 injection process, etc.), with activities in each step sometimes managed and operated by different operators, companies, or owners. When there are multiple parties involved in the process (e.g., if capture and storage are undertaken by different entities), and to avoid double counting of 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 through compliance with Section 2.5.3 of the Isometric Standard. The baseline scenario and counterfactual utilized to assess additionality must be project-specific, and are described in Section 7.42 of this Protocol.
Additionality determinations should be reviewed and completed every five years (aligned with the Crediting Period), at a minimum, or whenever project operating conditions change significantly, such as the following:
Any review and change in the determination of additionality should not affect the availability of Carbon Finance and Verified Credits for the current or past Crediting Periods, but if the review indicates Thethe Project has become non-additional, this will make Thethe Project ineligible for future Credits.13
The uncertainty in the overall estimate of the net CO2e removal as a result of Thethe Project must be calculated and transparently presented. The total net CO2e removed over a Reporting Period ([math: RP]; see Section 7.58) for a Project, [math: CO_2e_{Removal,\ RP}], must be conservatively determined, based on the requirements outlined in Section 2.5.7 of the Isometric Standard.
Projects must report a list of all input variables used in the net CO2e removal calculation and their uncertainties, 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.
In addition, a sensitivity analysis 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 so that the results can be re-created. Parameters may be omitted from a full uncertainty analysis if a Sensitivity Analysis can demonstrate that the parameter contributes to <1% change in removal. For all other parameters, information about Uncertaintyuncertainty must be specified.
In accordance with Section 3.8 of the Isometric Standard, all evidence and data related to the underlying quantification of the net CO₂2e removal 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, the Registry, and VVB) where it is subject to confidentiality. This includes emission factors from licensed databases. However, all other numerical data produced or used as part of the quantification of net CO2e removal will be made available.
Bio-CCS systems are typically operated continuously, with captured CO2 being transported and durably stored using a variety of potential processes. Due to the continuous nature of Bio-CCS systems, the equations used to calculate removals will pertain to all net emissions occurring over an interval of time. This unit of time is defined as the Reporting Period, [math: RP], which is the time period during which net CO2e removals are claimed by the Project Proponent and submitted for verification. The total net CO2e removal is written hereafter as [math: CO_2e_{Removal}].
GHG emission calculations must include all emissions related to the project activities that occur within the Reporting Period. This includes:
(i) any emissions associated with project establishment allocated to the Reporting Period (See Section 7.6.3.1),
(ii) any emissions that occur within the Reporting Period (See Section 7.6.3.2),
(iii) any anticipated emissions that would occur after the Reporting Period that have been allocated to the Reporting Period (See Section 7.6.3.3), and
(iv) leakage emissions that occur outside of the system boundary that are associated with the Reporting Period (See Section 7.6.3.4).
In line with the Isometric Standard, this Protocol requires that removal Credits are issued ex-post (after net removal from the atmosphere via Bio-CCS has been achieved). Credits may be issued once CO₂ has been permanently stored in the identified storage reservoir.
The scope of this Protocol includes GHG sources, sinks and reservoirs (SSRs) associated with a Bio-CCS Project.
A cradle-to-grave GHG Statement must be prepared encompassing the GHG emissions relating to the activities outlined within the system boundary.
GHG emissions and removals associated with Thethe Project may be as direct emissions from a process or storage system, or as indirect emissions from combustion of fuels, electricity generation, or other sources. Emissions for processes within the system boundary must include all GHG SSRs within the system boundary, from the construction or manufacturing of any project-specificeach physical site and associated equipment, closure and disposal of each site and associated equipment, and operation of each process (CO2 capture process, CO2 transportation, storage, and monitoring), including embodied emissions of equipment and consumables used in the processProject. 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 must be fully considered in the system boundary. Any activity that ultimately leads to the issuance of Credits should be included in the system boundary. Biomass feedstock emissions must be calculated as outlined in Section 3 of the Biomass Feedstock Accounting Module v1.3. This allows for accurate consideration of additional, incremental emissions induced by the carbon removal process.
The systemGHG Statement boundary must include all relevant GHG SSRs controlled, related and affected by and related to Thethe Project, including but not limited to the SSRs set out 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 Bio-CCS projects[Image: Figure 1]
Table 1. Scope of activities to be included in the system boundary for Bio-CCS projects
| Activity | GHG Source, Sink or Reservoir | GHG | Scope | Timescale of emissions and accounting allocation |
|---|---|---|---|---|
| Establishment of Project | Construction and installation | All GHGs | Equipment and materials manufacture, transport to site and construction site emissions. To include:
| Before project activities start - must be accounted for in the first Reporting Period or amortized in line with allocation rules (see Section |
| Initial surveys and feasibility studies | All GHGs | To include any embodied, energy use and transport emissions associated with surveys required for establishment of the | ||
| Misc. | All GHGs | Any SSRs not captured by categories above. | ||
| Operations | All GHGs | Over each Reporting Period - must be accounted for in the relevant Reporting Period (See Section | ||
| Biomass feedstock | All GHGs | |||
| Energy use | All GHGs | Energy consumption associated with the Project, for example through electricity or fuel use. | ||
| CO2 stored | CO2 only | The gross amount of CO2 removed and | ||
| Direct emissions | All GHGs | Direct emissions due to process leaks or fugitive emissions, releases, or GHG containing tailgas. See Section 8.2.3.2.1 for calculation details. | ||
| Consumables (other than feedstock) | All GHGs | Embodied emissions associated with consumables required for operation of the project site (excluding feedstock). | ||
| Waste processing | All GHGs | Waste processing and end-of-life disposal of components used within the process. | ||
| Sampling required for MRV | All GHGs | Sampling required for MRV, 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 the | ||
| Surveys | All GHGs | Equipment, energy use and transport associated with surveys e.g. ecological surveys | ||
| Maintenance of project site | All GHGs | To include actual or anticipated maintenance (lifecycle modules B2), repair (B3), replacement (B4) and refurbishment (B5) activities associated with project-specific site, equipment, vehicles, buildings or infrastructure over the | ||
| Misc. | All GHGs | Any SSRs not captured by categories above. | ||
| End-of-Life | End-of-life emissions | All GHGs | To include anticipated end-of-life emissions (lifecycle modules C1-4). | After Reporting Period - must be accounted for in the first Reporting Period or amortized in line with allocation rules (See Section |
| Sampling required long term monitoring for MRV | All GHGs | Ongoing monitoring, including transportation to collect samples, shipping of samples for laboratory analysis and sample processing. | ||
| Long term ongoing monitoring and surveys | All GHGs | Anticipated equipment, energy use and transport associated with ongoing monitoring and surveys e.g. ecological surveys. | ||
| Misc. | All GHGs | Any emissions source, sink or reservoir 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 considerreport any outside of the SSR categories identified as miscellaneous emissions.
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 in Section 8.2.3.4.
In line with the GHG Accounting Module v1.0, the Project must:
All;
Miscellaneous; GHGand
Emissions associatedline with a Project's impact on activities that fall outside of the system boundary of a Project must also be considered. This is covered under Leakage in Section 7.6.3.4.
Bio-CCS facilities will typically produce marketable co-products, e.g. energy, in addition to conducting CO2 capture activities. The system boundary of a Bio-CCS Project must include the full system as set out in Section 7.2, unless Eligibility Criteria are met which allow a more narrow system boundary to be drawn. Projects that meet at least one of the following Eligibility Criteria in Table 2 may draw a more narrow system boundary which only considers activities related to CCS.
Table 2. Eligibility Criteria for allowing a narrow system boundary for a Bio-CCS project
| ||
| ||
|
Emissions associated with activities, consumables, and equipment related to the CO2 capture, transportation and storage processes must always be included in the system boundary. In cases where The Project has demonstrated that the co-product facility is non-additional, universal equipment may be excluded from the system boundary if The Project meets at least one eligibility criteria to qualify for a narrow system boundary (see Table 2). However, additional load imposed on any universal equipment by the operations of the CCS process must be proportionally attributed within the system boundary.
Any energy use within the system boundary must be accounted for through theIsometric requirements set out in the Energy Use Accounting Module v1.2. In cases where projects exclude emissions associated with the production of an energy co-product, any reduction in the efficiency of the energy production as a result of the CDR process must be counted towards energy use of the CDR process.
Refer to Energy Use Accounting Module for the calculation guidelines.
Ancillary activities, such as supplementary research and development activities and corporate administrative activities, that are associated with a Project but are not directly or indirectly related to the issuance of Credits can be excluded from the system boundary.
Bio-CCS may have additional impacts on GHG emissions beyond the scope of this Protocol, that are not already associated with marketable co-products. For example, providing a source of secondary low carbon heat or electricity, avoiding landfill emissions and reducing waste transport emissions. These potential impacts are not included in this conservative GHG accounting framework.
The baseline scenario for a Bio-CCS Project is dependent on whether the CCS aspect of Thethe Project is part of a new-build facility, or a retrofit to an existing facility:
See Appendix B: Baselines for further guidance on constructing a Project baseline.
The counterfactual is any CO2 stored in the biomass feedstock that would have remained durably stored in the biomass feedstock in the absence of Thethe Project, in addition to any CO2 that would have been durably stored by the selected storage technology.
See Section 23.20 of Biomass Feedstock Accounting Module v1.3 for biomass counterfactual eligibility.
Bio-CCS systems are typically operated continuously, with captured CO2 being transported and durably stored using a variety of potential processes. Due to the continuous nature of Bio-CCS systems, the equations used to calculate removals will pertain to all net emissions occurring over an interval of time. This unit of time is defined as the Reporting Period, [math: RP], which is the time period during which net CO2e removals are claimed by the Project Proponent and submitted for verification. The total net CO2e removal is written hereafter as [math: CO_2e_{Removal Calculation
The following sections outline the process for calculating the net CO2e removed for each Reporting Period based on total mass stored during that period, written hereafter as [math: CO_2e_{Removal,\ RP}].
Net CO2e removal for a process utilizing Bio-CCS must be calculated as follows for a Reporting Period, [math: RP]:
[math: CO_2e_{Removal,\ RP} = CO_2e_{Stored,\ RP}\ –\ CO_2e_{Counterfactual,\ RP} -\ CO_2e_{Emissions,\ RP} ]
(Equation 1)
Where;
It should be noted that any potential reversals of CO2 storage in the final storage location occur after Credits have been issued so are not included in this equation. See Section 5.6 of the Isometric Standard for further information. Risk of reversal information is given in Appendix 1D: Risk of Reversal Questionnaire, with further information provided within the relevant storageStorage module storage moduleModule.
CO2eStored represents the cumulative total CO2 sequestered in all durable storage reservoirs over a Reporting Period. It is calculated as:
[math: CO_{2}e_{Stored} = F_{B} \times \sum_{i}^{N} CO_{2}e_{Storage,i}]
(Equation 2)
Quantification of [math: CO_2e_CO_{Stored2}e_{Storage}], measurements, and monitoring requirements for the different conversion and storage options isare detailed within the respective Modules.
See Section 3.4 for calculation of [math: CO_2e_{StoredStorage}] in saline aquifers.
See Section 3.4 for calculation of [math: CO_2e_{StoredStorage}] in depleted hydrocarbon reservoirs.
See Section 3.4 for calculation of [math: CO_2e_{StoredStorage}] via in-situ mineralization.
See Section 4.2.1 for calculation of [math: CO_2e_{StoredStorage}] via ex-situ mineralization in closed engineered systems. This is the authoritative source for calculating [math: CO_2e_{StoredStorage}] via carbonation in the built environment.
See Section 4.1 for calculation of [math: CO_2e_{StoredStorage}] via enhanced weathering in closed engineered systems.
Projects that capture CO2 that is not entirely of biogenic origin must determine the biogenic fraction that is eligible for Crediting ([math: F_{B}]). If all captured CO2 is biogenic, [math: F_{B}] = 1.
[/R-SH5B-0]Projects which use waste feedstocks which contain inseparable biogenic and fossil carbon must use Method A to determine [math: F_{B}]. The use of Method B may be permitted in certain instances, on a case-by-case basis in agreement with Isometric.
[/G-DR5A-0]Projects which use biogenic feedstocks co-fired with fossil fuels may use Method A or B to determine [math: F_{B}].
[/G-1D0Z-0]Once [math: F_{B}] is determined in accordance with Section 8.2.1.1.1 or Section 8.2.1.1.2, the [math: CO_{2}e_{Storage}] as determined by the appropriate storage Module(s) must be converted to eligible biogenic [math: CO_{2}e_{Storage}] using Equation 2.
[math: F_{B}] must be determined by
[math: F_{B}] must be conservatively determined using a carbon mass balance approach detailed by Equation 3.
[math: F_B = \frac{\sum_{i}^{N_B}(m_{Biomass,i} \cdot C_{Biomass,i})}{\sum_{i}^{N_B}(m_{Biomass,i} \cdot C_{Biomass,i}) + \sum_{i}^{N_{FF}}(m_{FF,i} \cdot C_{FF,i})}]
(Equation 3)
where
For Validation, all projects must estimate an average [math: F_{B}] based on:
The estimated [math: F_{B}] must be included in the PDD, and may be expressed as a monthly profile to account for seasonal variation, or on a per-feedstock basis if the feedstock has low variability.
[/G-N1WM-0]Type: Counterfactual
As outlined in Section 7.42, Referrefer to both the Biomass Feedstock Accounting Module v1.3 and the relevant storage module for calculation of counterfactual storage.
See Section 3.13 of the Biomass Feedstock Accounting Module v1.3 for calculation requirements.
Type: Emissions
[math: CO_2e_{Emissions,\ RP}] is is the total quantity of GHG emissions associated with the 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-lifeLife,\ RP}^{}+ \ {CO}_{2}^{}e_{Leakage,\ RP}^{}]
(Equation 24)
Where:
The following sections setprovide outan overview for each variable. Section 8.2.4 provides guidance on specific quantification requirements for activities included in each variable.
GHG emissions associated with project[math: CO_{2}e_{Establishment,\ RP}] establishment 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 upthrough untilto the first Reporting Period. Establishment emissions may be accounted for in the following ways, with the allocation method selected and justified by the Project Proponent:
The anticipated lifetime7 of Thethe ProjectGHG shouldAccounting beModule.
See reasonableSection justification7 and should be included inof the ProjectGHG DesignAccounting Document (PDD) to be assessed as part of project validation.Module
Allocation of project establishment emissions to removals must be reviewed at each Crediting Period renewal and any adjustments made. If the Project Proponent is not able to comply with the allocation schedule described in the PDD, e.g. due to changes in delivered volume or anticipated project lifetime, the Project Proponent must 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.
GHG emissions associated with [math: CO_2e_{Operations,\ RP}] must include all emissions associated with operational activities, including but not limited to the SSRs set out in Table 1. This includes all direct emissions as laid out in Section 8.2.3.2.1.
[math: CO_2e_{Operations,\ RP}] emissions occur over the Reporting Period for the deployment being Credited and are applicable to the current deployment only. [math: CO_2e_{Operations\ RP}] emissions must be attributed to the Reporting Period in which they occur. Allocation of emissions to different Reporting Periods or injection batches may be permitted in certain instances, on a case by case basis in agreement with Isometric.
Bio-CCS processes can generate direct emissions of non-biogenic CO2 and/or other GHGs due to:
Direct emissions reported under this section include non-biogenic CO2 and other GHGs. Biogenic CO2 released is reflected in reductions to the measured value of stored CO2 ([math: CO_{2eStored,RP}]), which determines net CO2e removal and crediting.
Additionally, Projects that comply with EC1 in the GHG Accounting Module v1.0, or EC1 in Table 2 may exclude direct emissions, provided these emissions were occuring and would continue to occur in the baseline scenario. This means direct emissions from additional feedstock sourced because of the CDR Project must be accounted for.
All GHGs within the system boundary emitted to the atmosphere must be accurately measured and reported.
All fossil emissions that are not captured by a Project’s capture process must be appropriately quantified. If within the system boundary, they must be reported as [math: CO_{2}e_{Direct\ Emissions,RP}] using the following calculation:
[math: CO_{2}e_{Direct\ Emissions,RP} = \sum_{n=1}^{nv} \sum_{i=1}^{N} V_{i} \cdot W_{n,i} \cdot GWP_{n} \cdot \Delta t_{i}]
(Equation 5)
Where:
For combustion process facilities for the provision of power or heat, measurements must be acquired in line with EN 14181 in addition to the requirements below:
For all other Projects:
In the event of a process malfunction (such as mechanical failure, gas leaks and/or PRV actuation events), direct measurement will sometimes not be possible and direct emissions through these routes must need to be documented and reported in the Reporting Period in which they occur, with best possible conservative estimations of emissions, in agreement with Isometric.
The Project Proponent must maintain the following records as evidence supporting calculation of direct emissions:
Records of all data and analyses must be maintained by the Project Proponent and provided for verification purposes for a period of five years.
In order to conservatively determine the fossil CO2 emitted due to the Project between capture and storage, the quantity of fossil CO2 captured must be quantified and the quantity of fossil CO2 proven to be durably stored by the Project must be deducted.
Projects which use waste feedstocks which contain inseparable biogenic and fossil carbon must use Method A to determine the direct emissions. Projects which use biogenic feedstocks co-fired with fossil fuels may use Method A or B to determine the quantity of fossil CO2.
[/R-D610-0][math: CO_{2}e{_{{Post-Capture\text{ }Emissions}}} = CO_{2}e{_{Captured}} \cdot (1-F_B) - \left(\sum CO_{2}e{_{Storage}} \cdot (1-F_B)\right)]
(Equation 6)
Where:
[math: CO_2e_{{Captured, RP}}] represents the gross amount of CO2 captured by the Project during a Reporting Period.
This can be calculated by using the mass and average concentration of CO2 over a given time period, summed across the whole [math: RP]:
[math: CO_2e_{Captured,\ RP} = \sum_{t=1}^{T} C_{mean,cap,t} \cdot m_{cap,t}]
(Equation 7)
Where:
The mass of CO2-containing fluid captured, [math: m_{cap,t}], may either be directly measured using a mass flow meter, or may be indirectly measured by combining suitable volume and density measurements. In the latter case, the mass is calculated as:
[math: m_{cap,t} = V_{cap,t} \cdot \rho_{cap,t} ]
(Equation 8)
Where:
The density of the fluid captured may be measured either using a calibrated density meter, or may be indirectly measured by combining suitable pressure and temperature measurements. In the latter case, the density should be determined as a function of the pressure and temperature measurements by application of a suitable gas-phase equation of state model. Supporting information, including appropriate published scientific literature and/or internal empirical evidence, demonstrating the accuracy of the applied equation of state must be provided at the point of project verification.
The concentration of CO2 in the captured fluid stream must be:
The mass of captured fluid ([math: m_{cap}]) is measured via use of a calibrated mass flow meter or volumetric flow meter and density measurements over a defined time interval (Δt). Preference is for high-accuracy flow meters such as coriolis or thermal mass flow meters, although other metering solutions are allowable. Flow metering must meet the following requirements:
Alternative methods of measuring the mass of CO2 captured on a batch basis may be accepted on a case-by-case basis in agreement with Isometric.
[math: CO_{2}e_{{Post-Capture\text{ }Emissions}} = \sum_{i}^{N_{FF}}(m_{FF} \cdot C_{FF}) - \left(\sum_{j}^{N} CO_{2}e_{{Storage,j}} \cdot (1-F_B)\right)]
(Equation 9)
Where:
[math: CO_2e_{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 ongoing sampling activities for MRV for the specific deployment (directly related), or end-of-life emissions for the projectProject facility (indirectly related to all deployments).
GHG emissions associated with [math: CO_2e_{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_2e_{Establishment,\ RP}].
Given the uncertain nature of [math: CO_2e_{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_2e_{End-of-Life,\ RP}] emissions associated with a Reporting Period, or Thethe Project as a whole, that occur after Thethe Project has ended, then the reversal process will be triggered to compensate for any emissions not accounted for.
[math: CO_2e_{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 Thethe 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 the Project Proponent's responsibility to identify potential sources of leakage emissions. As a minimum Bio-CCS projectsProjects must account for market leakage emissions in accordance with the Biomass Feedstock Accounting Module v1.3 and the relevant storageStorage modulesModules, as well as energy leakage associated with reductions in efficiency of wider processes, or reduction in energy outputs as a result of the CDR Project.
[math: CO_2e_{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.
The Project Proponent must identify, highlight and justify any data gaps and missing calibration data should they occur. Isometric and the VVB must be notified of data gaps and missing calibration data as soon as they become evident. Documentation that explains the approach taken and details the missing data must be provided to Isometric and the VVB and included in the GHG Statement.
For parameters that require sub-hourly measurements (such as direct GHG emission concentrations and flow rates), the Project Proponent must adhere to the following procedure for handling missing data events.
Where data gaps in measurements are 30 minutes or less in duration, the Project Proponent must use an average measurement utilising measurements taken 30 minutes prior to and following the data gap.
Where data gaps in measurements are longer than 30 minutes in duration, the Project Proponent must apply the above approach for up to a 30 minute period within the duration of the data gap only. For the remaining duration of the data gap the Project Proponent must assume a conservative stance in consultation with Isometric, depending on the nature of the data loss as detailed below:
In addition, data gaps must account for less than 5% of the data used for both the calculation of removals and the calculation of emissions within a given Reporting Period, any data missing above this threshold will also be subject to the conservative rules outlined above.
Where calibrations are missed, one must be completed as soon as this becomes evident. For data collected between when the calibration was required and when it took place, a conservative estimate should be agreed between the VVB, Project Proponent and Isometric.
GHG emissions accounting must 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. This includes:
Refer to GHG Accounting Module for emissions accounting guidelines.
Embodied emissions associated with system inputs considered to be waste products 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 v1.3.
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 v1.3 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 Bio-CCS process may result in the production of co-products, such as electricity and heat. Projects must follow the co-product allocation procedures described in Section 6.1 of the GHG Accounting Module v1.0. This includes provisions for a narrow system boundary in instances where the facility is a retrofit and provisions for applying the substitution method.
In addition to the requirements set out in the GHG Accounting Module v1.0, Bio-CCS projects may follow the additional provisions below for Procedure 2: Dividing the process into sub-processes (as set out in the GHG Accounting Module v1.0) if they comply with EC1 in Table 2.
[/G-3NB8-0]Table 2. Additional eligibility criteria for dividing the process into sub-processes
| Description | Documentation required | |
|---|---|---|
| EC1 | The Bio-CCS process is carbon capture on a new build waste incineration facility, but the building of the waste incineration facility without CCS would have occurred without the Project, and the waste incineration activities are in the Project baseline. | Robust justification of the non-additionality of the waste incineration facility without CCS, including counterfactual or current fate of the waste feedstocks accounting for the full projected facility capacity. Evidence for each waste feedstock that no alternative fate is possible (for example, legislation prohibiting landfill of the waste feedstock). |
For Bio-CCS Projects capturing both fossil and biogenic CO2, Project emissions ([math: CO_{2}e_{Emissions}]) by default must be fully allocated to the CDR Project. However, if the Project can satisfy all of Eligibility Criteria EC2 to EC5 in Table 3, they may undertake a mass-balance allocation of emissions to the biogenic fraction.
[/G-QA6X-0]Table 3. Eligibility criteria for mass balance emissions allocation
| Description | Documentation required | |
|---|---|---|
| EC2 | The Bio-CCS process uses waste feedstocks which contain inseparable biogenic and fossil carbon. | At least 50% of the total feedstocks used by the plant are comprised of inseparable biogenic and fossil carbon and are compliant with SC6 from the Biomass Feedstock Accounting Module v1.3. |
| EC3 | The Bio-CCS process is within the scope of a sufficiently rigorous cap-and-trade-scheme. | The fossil emissions from the capture facility must be within the scope of a cap-and-trade scheme listed in Appendix C. |
| EC4 | The Bio-CCS Project can demonstrate that CCS of the fossil emissions would not happen without the CDR revenue. | Evidence submitted against the Additionality requirements in the Isometric Standard must also demonstrate that capture and storage of the fossil emissions would not happen without CDR revenue. |
| EC5 | The Bio-CCS Project must demonstrate with full allocation of Project emissions the Project is still net negative. | Project Proponents must demonstrate at each Verification that if the GHG Statement did not undertake allocation based on mass-balance of biogenic fraction, the Project would still be net negative. |
If eligible, Projects may allocate Project emissions to the biogenic fraction by multiplying relevant Project emissions by [math: F_B] in line with Equation 10. Relevant Project emissions are those where the same processes are shared between fossil and biogenic CO2 capture and storage. [math: CO_{2}^{}e_{Leakage}] emissions must not be allocated.
[math: {CO}_{2}^{}e_{Emissions,\ RP}^{}\ = \ F_B\ *\ ({CO}_{2}^{}e_{Establishment,\ RP}^{}\ + \ {CO}_{2}^{}e_{Operations,\ RP}^{} + \ {CO}_{2}^{}e_{End-of-Life,\ RP}^{}) \ + \ {CO}_{2}^{}e_{Leakage,\ RP}^{}]
(Equation 10)
Where
This section ofsets theout Protocol outlinesspecific requirements for emissions accounting relating to quantification of energy use, transportation,as andpart embodiedof emissionsthe associatedGHG withStatement. a CDR Project.
Emissions associated with energy usage, whetherresult throughfrom the consumption of electricity or fuel use, must be accounted for throughout all phases.
Examples of theelectricity process.
Energy related emissionsusage may include, but are not limited to:
Process emissions associated with Thethe Project will be calculated by totaling the energy use (thermal and electrical) of all equipment within the project boundary. To determine the energy use, the following measurements must be provided:
Electricity:
When the electricity is provided to the CCS processes via the output of a Bio-CCS facility which produces electricity, the cradle-to-grave emissions factor for the bioenergy facility shall be used as the primary emissions factor for calculation of electricity related emissions for the CDR process.
Electricity metering and record keeping must be performed in accordance with the Energy Use Accounting Module v1.23.
Refer to the Energy Use Accounting Module for requirements.
Thermal Energy
Any thermal energy used by the CDR process must be monitored, including steam use, direct combustion of fuels within the CDR process to provide heat, and use of waste heat.
In the case of steam, waste heat, or other thermal inputs to the CDR Process, measurements must be made of the total thermal energy supplied to the CDR Process. Total thermal energy must be measured using the following methods:
Emissions associated with thermal energy and its production, and record keeping, must be performed in accordance with the Energy Use Accounting Module v1.23.
The Energy Use Accounting Module v1.23 provides requirements on how energy-related emissions must be calculated so that they can be subtracted in the net CO2e removal calculation. It sets out the calculation approach to be followed for intensive facilities and non-intensive facilities and acceptable emissions factors.
Refer to Energy Use Accounting Module for the calculation guidelines.
EmissionsThis section sets out specific requirements relating to quantification of emissions related to transportation.
Emissions viaassociated freightwith transportation services,should suchinclude transportation of products as rail,part truck,of ora maritimebatch transport[math: mustn]’s be accounted forprocess, including the following:
TheSection Transportation4.2 Emissionsof the GHG Accounting Module v1.10 provides requirements on how transportation-related emissions must be calculated so that they can be subtracted in the net CO2e removal calculation. It sets out the calculation scope, approach to be followed, and acceptable emissions factors.
ReferSee to Transportation EmissionsGHG Accounting Module for theeligibility calculation guidelinescriteria.
EmbodiedThis GHGsection sets out specific requirements relating to quantification of embodied emissions associatedas withpart of the manufacturing,GHG delivery, and installation of all equipment and consumables that lie within the system boundary must be accounted for in each Reporting PeriodStatement. Embodied emissions are those related to the life cycle impact of equipment and consumables.
The Project Proponent must identify all equipment and consumables used in the biomass conversion and storage process, identify appropriate cradle to grave emission factors, and allocate the emissions to removals appropriately.
Examples of project-specific materials, equipment and consumablesequipment that must be considered as part of the embodied emission calculation include but are not limited to:
Equipment, including:
Equipment and infrastructure for processes relating to the wider facility, for example energy generation or product manufacturing.
CO2 Capturecapture Processprocess:
CO2 transportation:
CO2 storage:
Monitoring:
Universal equipment for all processes:
Consumables, including:
Consumables for processes relating to the wider facility, for example energy generation or product manufacturing.
Capture Process:
CO2 storage:
Monitoring:
Universal consumables for all processes:
The Embodied EmissionsGHG Accounting Module v1.0 sets out the calculation approach to be followed including allocation of embodied emissions, life cycle stages to be considered, data sources and emission factors.
ReferSee to Embodied EmissionsGHG Accounting Module for theeligibility calculation guidelinescriteria.
Miscellaneous GHG emissions for emissions associated with a given Reporting Period are those not included in the SSR categories provided in Table 1. The Project Proponent is responsible for identifying all sources of emissions directly or indirectly related to project activities.
Miscellaneous GHG emissions must consider direct emissions of non-CO2 GHGs due to process leaks or fugitive emissions, releases, or GHG containing tailgas from:
Quantification of emissions associated with direct emissions of non-CO2GHGs requires two primary measurements, the measurement of the total quantity of emissions and the analysis of emissions for CO2 and other GHG content. This can be calculated as follows:
[math: CO_{2}e_{MiscProject} = \sum_{t=1}^{T} m_{em,t} \cdot\ C_{GHG,t} \cdot\ GWP_{GHG}]
(Equation 3)
Where:
The total quantity of direct emissions can be measured by various acceptable methods, including:
The concentration of GHGs in direct emissions must be measured directly via one of the following methods:
The Project Proponent must maintain the following records as evidence supporting calculation of direct emissions:
Records of all data and analyses must be maintained by the Project Proponent and provided for verification purposes for a period of five years.
This Protocol provides multiple options for conversion and durable storage of CO2. The Project Proponent can choose from available options when submitting their Project for verification:
CO2 storage in saline aquifers.
CO2 storage in depleted hydrocarbon reservoirs.
CO2Durability and monitoring requirements for storage in mafic and ultramafic formations.
Must be used with the carbonation in the built environment storage module.
Must be used with the ex-situ mineralization in closed engineered systems conversion moduleModule.
Must be used with the dissolved inorganic carbon in oceans storage module.
Must be used with the enhanced weathering in closed engineered systems conversion moduleModule.
Isometric would like to thank following contributors to previous versions this Protocol and relevant Modules:
This section provides guidance for Projects which capture fossil CO2, whether through mixed feedstocks or co-firing with fossil fuels.
Note that for the purposes of this Protocol, geologic CO2 liberated from minerals is considered fossil CO2 unless it can be demonstrated that the CO2 is of biogenic origin and mineralized by the Project (for example, as a sorbent).
For CO2 leaks prior to the point of quantification of [math: CO_{2}e_{Storage}](according to the storage Module), for eligible biogenic CO2 there is no penalty for emitting CO2, as in the counterfactual scenario this CO2 would have entered the atmosphere.
However, whether emitted fossil CO2 is considered within the system boundary is dependent on The Project type:
Once fossil CO2 is durably stored by the Project, any emission of CO2 from the storage reservoir attributable to the Project is considered a reversal, regardless of [math: F_{B}], excluding fossil CO2 that can be robustly demonstrated to be part of the baseline scenario (see Appendix B: Baselines), in agreement with Isometric and the VVB.
For quantification of the fossil component of any mixed CO2 emission from the Project, use Equation A1.
[math: CO_{2}e_{{Misc, Fossil}} = (1-F_B) \cdot CO_{2}e_{Misc}]
(Equation A1)
Where
For guidance on the construction of a baseline for a Project that is drawing a narrow system boundary, see Appendix D of the Biomass Feedstock Accounting Module v1.3. The concept of Baseline Feedstock Consumption rate can be applied to drawing a baseline fossil fuel usage. Usage of fossil fuels above this rate must be within the system boundary.
Factors that characterize a robust cap-and-trade policy include:
Currently the EU Emissions Trading Scheme, which covers the 27 EU member nations as well as Iceland, Norway, and Liechtenstein; and the UK Emissions Trading Scheme are the only cap-and-trade jurisdiction approved as sufficiently rigorous under this Protocol.
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 projectProject, 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 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 protocolProtocol, 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 |
| 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 | |
| 7 | Applicable only for subsurface storage: Is the carbon being stored with trapping mechanisms preventing reversals? (e.g., multiple confining layers, CO | Minus 1 to Risk Score (unless 0) | |
| 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 inorganic carbon, the presence 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 following contributors to this Protocol and relevant Modules:
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Methodology for assessing the quality of carbon Credits, Version 3.0. (2022, May). https://carbonCreditquality.org/methodology.html
NIST (2015, April 20). Overview of ASTM D7036: A Quality Management Standard for Emission Testing. https://www.nist.gov/system/files/documents/2017/10/31/overview-astm-d7036.pdf
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US Department of Energy. (2022) Best Practices for Life Cycle Assessment (LCA) of Direct Air Capture with Storage (DACS). https://www.energy.gov/sites/default/files/2022-06/FECM%20DACS%20LCA%20Best%20Practices.pdf
U.S. Environmental Protection Agency. (2023, April 18). Understanding Global Warming Potentials | US EPA. Environmental Protection Agency. Retrieved June 14, 2023, from https://www.epa.gov/ghgemissions/understanding-global-warming-potentials
California Air Resources Board (2018). CCS Protocol under the Low Carbon Fuel Standard (LCFS). https://ww2.arb.ca.gov/sites/default/files/2020-03/CCS_Protocol_Under_LCFS_8-13-18_ada.pdf
Terlouw, T., Bauer, C., Rosa, L., Mazzotti, M. (2021). Life cycle assessment of CO2 removal technologies: a critical review. Energy & Environmental Science. https://doi.org/10.1039/D0EE03757E
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Custelcean, R. (2022). Direct Air Capture of CO2CO2 Using Solvents. Annual Review of Chemical and Biomolecular Engineering, 13, 217–234. https://doi.org/10.1146/annurev-chembioeng-092120-023936↩
Fujikawa, S., and Selyanchyn, R. (2022). Direct air capture by membranes. MRS Bulletin, 47, 416–423. https://doi.org/10.1557/s43577-022-00313-6↩
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Al Hameli, F., Belhaj, H., and Al Dhuhoori, M. (2022). CO2CO2 Sequestration Overview in Geological Formations: Trapping Mechanisms Matrix Assessment. Energies, 15, Article 20. https://doi.org/10.3390/en15207805↩
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Ricks, W., Xu, Q., and Jenkins, J. D. (2023). Minimizing emissions from grid-based hydrogen production in the United States. Environmental Research Letters, 18, 014025. https://doi.org/10.1088/1748-9326/acacb5↩
Erans, M., Sanz-Pérez, E. S., Hanak, D. P., Clulow, Z., Reiner, D. M., and Mutch, G. A. (2022). Direct air capture: Process technology, techno-economic and socio-political challenges. Energy & Environmental Science, 15, 1360–1405. https://doi.org/10.1039/D1EE03523A↩
For example, 49 CFR §195.402 - Transportation of Hazardous Liquids via Pipeline: Procedural manual for operations, maintenance, and emergencies, and 40 CFR §146.94 - Class VI Wells: Emergency and remedial response. ↩↩2
Water neutrality is defined as: the total demand for water should be the same after new development is built, as it was before. That is, the new demand for water should be offset in the existing community by making existing infrastructure and homes in the area more water efficient. ↩
ISO 14064-3: 2019, Section 5.1.7 ↩
Carbon Credit Quality Initiative. Methodology for assessing the quality of carbon credits, Version 3.0 (May 2022). https://carboncreditquality.org/methodology.html↩
Lyons, L., Kavvadias, K. and Carlsson, J., (2021). Defining and accounting for waste heat and cold. EUR 30869 EN, Publications Office of the European Union, Luxembourg. doi:10.2760/73253. https://publications.jrc.ec.europa.eu/repository/handle/JRC126383↩
Flow meters must be calibrated to national traceable standards by an ISO 17025 accredited metrology laboratory. Flow meters may include critical nozzle flow meters (i.e. ISO 9300:2022 compliant meters), coriolis mass flow meters, and other applicable meters for mixed gas flows, as long as properly calibrated and maintained. ↩
Dinh, T.-V., Choi, I.-Y., Son, Y.-S., and Kim, J.-C. (2016). A review on non-dispersive infrared gas sensors: Improvement of sensor detection limit and interference correction. Sensors and Actuators B: Chemical, 231, 529–538. https://doi.org/10.1016/j.snb.2016.03.040↩
Sandoval-Bohorquez, V. S., Rozo, E. A. V., and Baldovino-Medrano, V. G. (2020). A method for the highly accurate quantification of gas streams by on-line chromatography. Journal of Chromatography A, 1626, 461355. https://doi.org/10.1016/j.chroma.2020.461355↩
Lyons, L., Kavvadias, K. and Carlsson, J., (2021). Defining and accounting for waste heat and cold. EUR 30869 EN, Publications Office of the European Union, Luxembourg. doi:10.2760/73253. https://publications.jrc.ec.europa.eu/repository/handle/JRC126383↩