These FAQs refer to the Gold Standard Rule Update fNRB Application for GS4GG Certification
- What is Gold Standard’s recent announcement on fNRB?
- What is the purpose of the fNRB Rule Update document?
- Which projects and activities are affected by the new fNRB Rule Update?
- What are the key deadlines related to using current fNRB values and CDM Tool 30?
- What are the new eligible methods for determining fNRB values after the specified deadlines?
- How do these changes affect already registered projects, and is it possible to maintain the validated methodology with the existing fNRB value for ongoing projects?
- Do project developers need to update the fNRB value of design certified projects before the 31 December deadline?
- Can project developers cancel and re-issue GS VERs using an updated fNRB method?
- What is meant by 'new activities' regarding the discontinuation of CDM Tool 30 for fNRB calculations effective June 30, 2025?
- Does the December 31, 2025 deadline for using current fNRB values refer to the monitoring period end date or the date the monitoring report is submitted?
- To use current fNRB values for monitoring periods through December 31, 2025, when does the validation submission for new activities need to be completed by?
- How does Gold Standard ensure regulatory stability for long-term projects given potential future fNRB updates from evolving tools like MoFuSS or new methods?
- Is there a fee associated with the mandatory design change required to update fNRB values?
- If a project plans to scale up using a design change in 2025, could the additional component use the registered fNRB value until the end of 2025?
- What are the implications if a new fNRB value reduces the registered scale of a project?
- Can project developers switch to a different fNRB method in the future? (e.g. a change from MoFuSS to an approved PACM-A6.4 method)
- Can a project developer adopt fNRB as a monitored parameter, rather than a fixed parameter?
- Applying MoFuSS
- Does the decision to discontinue CDM Tool 30 and mandate new methods consider that tools like MoFuSS are still evolving?
- How should community-level fNRB values, such as those from MoFuSS maps, be applied if they are more granular options than national or regional values?
- Can Gold Standard provide a procedure or guidance booklet to calculate fNRB, given that Tool 30 lacked clear explanations?
- Can projects voluntarily use a lower fNRB than the lowest rate found in the three eligible methods? Some A6 buyers, for example, require a 30% fNRB rate - which can be below rates found in MoFuSS, Tool 33 and/or PACM.
- Can an official fNRB value issued by a government in a Least Developed Country (LDC) be used to calculate emission reductions for CCP labelling?
- Will a new version of Tool 30 be released?
- What is Gold Standard doing to educate and engage buyers on the meaning of fNRB updates to enable higher prices for projects that apply the new values?
- Given that fNRB values are decreasing, impacting project finances, is there a plan to incentivize projects (e.g., reducing fees)?
- By updating the fNRB, will GS-VERs become CCP eligible?
What is fNRB?
The fraction of non-renewable biomass (fNRB) is a key parameter in carbon accounting methodologies, especially those related to clean cooking technologies. It represents the proportion of biomass (such as wood or charcoal) that is harvested from non-renewable sources—in other words, sources where the rate of extraction exceeds the rate of regeneration.
A higher fNRB means a greater share of biomass is unsustainably sourced, which results in higher carbon emissions. Therefore, switching to more efficient stoves or cleaner fuels can lead to greater emission reductions in areas with high fNRB values.
Decision and Timelines
What is Gold Standard’s recent announcement on fNRB?
In response to the changing market landscape, Gold Standard published a phased implementation timeline for the revision of fNRB methods within new and design-certified projects. The Rule Update also marks the inclusion of the MoFuSS model under Gold Standard as one of the methods to estimate the fNRB values for GS4GG certification.
From 31 December 2025, all fNRB values previously applied in design-certified projects will expire. For new activities, Clean Development Mechanism (CDM) Tool 30 will no longer be eligible after 30 June 2025. After these deadlines, projects must use updated fNRB estimation approaches/values, including:
- Modelling Fuelwood Saving Scenario (MoFuSS)
- CDM Tool 33 (default values, to be updated following CDM Executive Board decisions later in the year)
- Tool 33 version 2 or earlier versions are not valid.
- A revised Tool 30 under the Paris Agreement Crediting Mechanism (PACM – Article 6.4)
- Other approved methods under PACM – Article 6.4
For full details, please see our Rule Update: fNRB Application for GS4GG Certification
What is the purpose of the fNRB Rule Update document?
This rule update establishes new requirements for applying the Fraction of Non-Renewable Biomass (fNRB) in Gold Standard for the Global Goals (GS4GG) certification across all project statuses and methodologies. It provides updated requirements for GSVER issuance and labelling, considering recent decisions by the CDM Executive Board and Methodology Panel recommendations. This update supersedes all previous GS4GG requirements regarding fNRB application, including principles, methodologies, tools, and GHG product requirements
Which projects and activities are affected by the new fNRB Rule Update?
This rule update applies to all activities (standalone activities, PoAs, real or regular case VPAs, including VPAs/CPAs) with any certification status (listed, certified design, certified project) that apply the fNRB parameter in their emission reduction estimation. This includes projects using Gold Standard or CDM approved methodologies (all versions), using any methodology tool, method, or default value to determine fNRB, and seeking GS4GG certification for issuance of GSVERs or labelling of issued credits.
What are the key deadlines related to using current fNRB values and CDM Tool 30?
The validity of current fNRB values calculated using either the methodology's prescribed method or CDM Tool 30 expires for GS4GG certification on December 31, 2025. Projects seeking issuance or labelling of GSVERs shall not apply these current fNRB values for monitoring periods after December 31, 2025.
For design certification or renewal of crediting periods, the validity of CDM Tool 30 ends on June 30, 2025. Project developers shall not apply CDM Tool 30 for fNRB value estimation for these purposes after June 30, 2025. Requests for design certification, crediting period renewal, or VPA inclusion using Tool 30 shall not be submitted after June 30, 2025.
What are the new eligible methods for determining fNRB values after the specified deadlines?
After the deadlines (December 31, 2025, for monitoring periods; June 30, 2025, for design certification/renewal), project developers shall use one of the following eligible methods to estimate fNRB values for GSVER issuance, design certification, activity inclusion, or crediting period renewal:
- Modelling Fuelwood Saving Scenario (MoFuSS) derived values.
- Updated version of Tool 33 Default values (version 2.0 or earlier are invalid) after CDM Executive Board approval, or a revised version of Tool 30 under PACM-A6.4.
- New methods developed and approved for fNRB calculation under PACM-A6.4 (approved by Gold Standard).
Project developers may choose to apply these eligible methods earlier before the deadlines via a design change process.
How do these changes affect already registered projects, and is it possible to maintain the validated methodology with the existing fNRB value for ongoing projects?
The changes affect already registered projects to ensure alignment with the latest scientific understanding and to maintain credibility. Gold Standard understands and acknowledges the financial impact, yet these updates are necessary for environmental integrity, market understanding of quality credits, and compatibility with evolving market consensus. Maintaining previous fNRB values throughout existing crediting periods is not possible, as it would compromise integrity, create inconsistencies, and risk the credibility of credits. Gold Standard has provided a transition period until December 2025 and flexible implementation pathways, along with fee reductions for certification and issuance in early 2025, to help mitigate financial impacts.
Do project developers need to update the fNRB value of design certified projects before the 31 December deadline?
Revision of fNRB by 31 December 2025 is not mandated to maintain Gold Standard Design Certification. However, a project will not be able to issue GSVERs for a monitoring period after 31st Dec until the fNRB has been revised.
Project developers may choose to apply the updated value before the deadline.
Can project developers cancel and re-issue GS VERs using an updated fNRB method?
Gold Standard does not permit retroactive re-verification of already issued credits using new fNRB values. This policy preserves the integrity and finality of past issuances, since applying new methodological elements retroactively would challenge the validity of the original verification decisions. The priority is to implement updated requirements for future issuances while protecting the credibility of past certifications decisions.
What is meant by 'new activities' regarding the discontinuation of CDM Tool 30 for fNRB calculations effective June 30, 2025?
'New' refers to activities that have not yet been submitted for design certification. This means that regardless of their current status (listed or under validation), activities not submitted for design review by June 30, 2025, will be considered new activities and cannot use CDM Tool 30 for fNRB calculations for design certification or crediting period renewal.
Does the December 31, 2025 deadline for using current fNRB values refer to the monitoring period end date or the date the monitoring report is submitted?
The application of new fNRB values applies based on the monitoring period validity; specifically, current fNRB values cannot be applied for monitoring periods after December 31, 2025. This is regardless of when the monitoring report for that period is submitted for performance review.
For monitoring periods spanning across the deadline (e.g., Aug 2025 to Aug 2026), current fNRB values can be used for the pre-2026 portions (Aug-Dec 2025), and updated fNRB values from MoFuSS or other eligible methods shall be applied for the portions after December 31, 2025 (Jan-Aug 2026).
To use current fNRB values for monitoring periods through December 31, 2025, when does the validation submission for new activities need to be completed by?
To use current fNRB values for monitoring periods up to December 31, 2025, developers must submit their design review request with positive validation opinion by June 30, 2025. Any design review requests submitted after June 30, 2025, must use the eligible methods or default values specified in the rule update. This also applies to any transitioning project, programme, VPAs, i.e. transition from CDM or other voluntary standards.
How does Gold Standard ensure regulatory stability for long-term projects given potential future fNRB updates from evolving tools like MoFuSS or new methods?
Gold Standard follows a structured approach for methodology updates, including regular review periods (typically 3-5 years) to assess scientific developments and improvements. They provide advance notice of significant changes, transition periods for adaptation, and stakeholder consultation. While specific fNRB values cannot be guaranteed unchanged over a project's lifetime, Gold Standard strives for changes based on robust scientific evidence, transparency, adequate implementation timeframes, and consideration of economic impacts. They follow fixed periods (typically 3-5 years) for using specific versions of fNRB values to ensure stability and create update pathways considering both existing and new projects. Projects can also manage this risk by building conservative estimates into financial models and including provisions in offtake agreements.
Design Change Requirements
Is there a fee associated with the mandatory design change required to update fNRB values?
If the design change to update fNRB values is submitted as part of a performance review (issuance track), no additional fee will be charged. However, if the design change is submitted independently, the standard design change fee will be applicable.
If a project plans to scale up using a design change in 2025, could the additional component use the registered fNRB value until the end of 2025?
No, if a project needs to expand its scale, boundary, or other aspects via design change before the end of 2025, the new fNRB values must be adopted for the entire project. This is because the expansion will be treated as a new activity component. To maintain consistency and ensure conservativeness, the new fNRB values and eligible methods must be applied across the entire project.
What are the implications if a new fNRB value reduces the registered scale of a project?
As per the Design Change Request Requirements and Procedures, Project Developers shall assess the extent to which design changes affect the project’s scale according to GS4GG requirements.
Updates to fNRB values do not necessarily require a change in the scale of the activity; therefore, the certified scale of a project remains unchanged unless the developer explicitly requests a scale change. Additionally, project scale is not solely determined by the number of emission reductions, and changes to the fNRB value may not influence the scale. If a design change request includes a proposed change in scale, it will be reviewed and assessed accordingly.
Can project developers switch to a different fNRB method in the future? (e.g. a change from MoFuSS to an approved PACM-A6.4 method)
Yes, project developers may update their chosen fNRB method or value when new methods or default values become available after design certification or crediting period renewal.
Can a project developer adopt fNRB as a monitored parameter, rather than a fixed parameter?
In some methodologies, such as TPDDTEC, fNRB may either be fixed or monitored.
In line with parameter ICS 17 in TPDDTEC V.4, one of the following options for fNRB may be chosen and fixed at design certification:
- Determined ex-ante and fixed for a given crediting period
- Updated biennially or at each monitoring and verification
Applying MoFuSS
Does the decision to discontinue CDM Tool 30 and mandate new methods consider that tools like MoFuSS are still evolving?
Gold Standard acknowledges these concerns. The default scenario version of the MoFuSS tool is currently available. While further development is ongoing, developers may update their fNRB values as more advanced versions become available. Current MoFuSS values have undergone rigorous validation and are considered sufficiently robust for implementation. Project developers will receive adequate notice of any changes to implementation timelines or requirements. The rule updates provide flexibility to update fNRB values, including changing options after registration.
How should community-level fNRB values, such as those from MoFuSS maps, be applied if they are more granular options than national or regional values?
The selection of the appropriate fraction of Non-Renewable Biomass (fNRB) value is a critical step in quantifying emission reductions for projects involving biomass. The primary determinant for this selection is the methodology and geographical scope defined within the project's registered Project Design Document (PDD).
1. Adherence to Registered PDD:
The fNRB value applied to a project must align with the geographical boundary specified in its registered PDD. Typically, PDDs will define whether the fNRB should be based on:
- A national-level default or calculated fNRB value for defined project boundary.
- A specific regional-level (e.g., provincial, state, or other defined sub-national area) default or calculated fNRB value.
This registered approach is the binding requirement for fNRB determination unless a formal deviation is justified and approved according to applicable rules of Gold Standard.
2. Deviation from registered project boundary for fNRB and Application of Weighted Average:
In instances where a project developer seeks to deviate from the PDD's stipulated national or regional approach to utilize more granular data—for example, by estimating fNRB based on individual community-level values (such as those derived from MoFuSS maps)—a weighted average approach may be applied.
This is necessary to aggregate the more detailed community-level data into a single, representative fNRB value for the entire project area. Simply using an unweighted average or cherry-picking values would not be considered a robust or conservative approach.
How the Weighted Average Shall Be Applied:
When using weighted average fNRB values, the weighted average is calculated to ensure that each community's fNRB contributes to the overall project fNRB in proportion to its significance. The fNRB values from each distinct community within the defined project boundary should be weighted by one or more of the following relevant factors:
Number of Participating Households: For projects targeting specific households (e.g., improved cookstove dissemination programs), the fNRB for each community can be weighted by the number of households participating in the project within that community.
- Calculation Example: Project fNRB = Total Participating Householdsproject area∑(fNRBcommunityi×Participating Householdscommunityi)
Estimated Biomass Consumption: This is often the most direct and impactful weighting factor. If credible data or robust estimates exist for the total woody biomass (fuelwood and charcoal) consumed in each community, these consumption figures should be used to weight each community's fNRB.
- Calculation Example: Project fNRB = Total Biomass Consumptionproject area∑(fNRBcommunityi×Biomass Consumptioncommunityi)
3. Important Considerations for Deviation:
Formal Approval: Any deviation from the fNRB approach outlined in the registered PDD, including the adoption of a weighted average of community-level data, must be thoroughly justified, transparently documented, and receive formal approval from Gold Standard following design changes process. The deviation may be as part of design change request, and no separate deviation submission is needed.
Data Integrity: The data used for weighting (e.g., household numbers, biomass consumption figures) must be accurate, verifiable, sourced reliably, and as up to date as possible.
Conservativeness: The chosen methodology for weighting and the underlying data should ensure that the final project fNRB value is conservative and does not lead to an overestimation of emission reductions.
In all cases, the registered PDD remains the foundational document guiding fNRB value determination. If a more refined, community-based approach is deemed more accurate and is pursued, the weighted average method provides a structured way to integrate this granular data, subject to proper justification and approval.
Summary of fNRB Selection Process
The selection of fNRB values must follow these key principles:
- Follow the geographical scope (national or regional) specified in your registered PDD
- If using community-level data:
- Apply weighted averages based on household numbers or biomass consumption
- Get formal approval for any deviation from the PDD
- Ensure data accuracy and conservative estimates
Can Gold Standard provide a procedure or guidance booklet to calculate fNRB, given that Tool 30 lacked clear explanations?
Currently, default values are available through the MoFuSS tool. Additional methodological guidance and detailed calculation guidelines for future methods will be provided to support project developers in implementing these approaches effectively
CDM Tool 33
Is Tool 33 available for application? What is Gold Standard's position if the updated CDM Tool 33 is not approved by the Executive Board in 2025?
Tool 33 is still under development. Gold Standard is hopeful that the Executive Board will make a final decision on Tool 33 in July 2025, given its critical importance. Meanwhile, MoFuSS is already available for project developers for Gold Standard certification. If these efforts don't yield positive outcomes, Gold Standard will work with its technical advisory committee to assess other viable options, including the development of new methods.
What are the expected changes in the new updated Tool 33 and how will it affect existing registered projects?
The updated version of Tool 33 is still under development. The impact of Tool 33 updates on existing projects will vary depending on project-specific circumstances. The extent of changes will be determined by the difference between current values and updated values generated by MoFuSS. Project developers should access MoFuSS directly to check the latest applicable values for their project area and compare them with existing values to understand potential impacts. This project-specific approach ensures developers can accurately assess and plan for any necessary adjustments. Tool 30 is being phased out and will be replaced by default values in Tool 33.
Other Methods
Can projects voluntarily use a lower fNRB than the lowest rate found in the three eligible methods? Some A6 buyers, for example, require a 30% fNRB rate - which can be below rates found in MoFuSS, Tool 33 and/or PACM.
The project developer should use one of the eligible methods to determine the fNRB value. Along with conservativeness, the methodology requires to ensure the accuracy and consistency thus a lower fNRB may not be appropriate and allowed for use.
Can an official fNRB value issued by a government in a Least Developed Country (LDC) be used to calculate emission reductions for CCP labelling?
No, according to the list of eligible methods provided by ICVCM, an official fNRB value issued by the government of an LDC cannot be used for calculating emission reductions or obtaining the CCP label, as it is not among the methods approved by ICVCM. Project developers must instead use one of the listed eligible methods (MoFuSS, updated Tool 33, etc.) to determine the fNRB value for CCP labelling. While country-specific literature exists, it cannot be used directly until a standardized methodology is approved by UNFCCC.
Will a new version of Tool 30 be released?
TOOL30 is currently being phased out and will be replaced by default values in TOOL33, with transition measures in place for existing projects. This reflects a broader shift toward newer, more robust methods for determining fNRB values. While the methodology panel is seeking stakeholder input on new approaches to improve accuracy and conservativeness, the UNFCCC has not yet announced when these changes will take effect.
Charcoal Users
How should fNRB be used for charcoal users compared to wood fuel users, especially regarding conversion factors?
The developer shall follow the methodology requirements to determine the fNRB for their project type. As per current methodologies and ICVCM guidelines, the developer for charcoal projects should either use a direct charcoal emission factor that includes production emissions or apply a wood-to-charcoal conversion factor. The direct charcoal emission factor used in Gold Standard methodologies effectively translates to approximately a 3.5:1 wood-to-charcoal conversion ratio, which is more conservative than the 4:1 ratio suggested in ICVCM guidelines. Therefore, projects using the direct emission factor are already compliant and no further adjustments are needed to meet CCP requirements regarding this conversion factor.
Market Implications
What is Gold Standard doing to educate and engage buyers on the meaning of fNRB updates to enable higher prices for projects that apply the new values?
Gold Standard is actively engaged in market-wide initiatives and collaborative partnerships to help stakeholders understand the importance and necessity of fNRB updates. Raising awareness about how updated fNRB values ensure alignment with current scientific understanding. We expect market recognition for projects that implement these more accurate and conservative values, anticipating that alignment with best practices and scientific rigor should positively influence buyer preferences and valuation of credits.
Given that fNRB values are decreasing, impacting project finances, is there a plan to incentivize projects (e.g., reducing fees)?
Gold Standard demonstrated its commitment by implementing fee reductions for certification and issuance in early 2025. While they cannot control third-party costs like VVB fees or market prices, they anticipate that stakeholders throughout the carbon market ecosystem will collaborate to maintain the financial viability of these essential projects.
By updating the fNRB, will GS-VERs become CCP eligible?
For details on the CCP eligibility of clean cooking projects, please see our CCP labelling Requirements and associated FAQs.
For any remaining questions please contact us at help@goldstandard.org
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