Appendix B: NbS Rating Agency Comparative Analysis
This appendix provides detailed profiles of four entities that rate, assess, or provide quality frameworks for Nature-based Solutions (NbS) carbon credits: Sylvera, BeZero Carbon, Calyx Global, and Verra (through its Nature Framework). These entities represent the current frontier of NbS quality assessment relevant to banking product structuring. The analysis covers organisational characteristics, methodological approaches, coverage, and gaps, with particular attention to alignment with the multi-domain rating framework proposed in this report.
1. Agency Profiles
1.1 Sylvera
| Field | Detail |
|---|---|
| Founded | 2020 |
| Headquarters | London, United Kingdom |
| Team size | Approximately 120-150 employees (as of 2024) |
| Funding/backing | Series B funding of US$57 million (2023), led by Balderton Capital. Total funding exceeds US$80 million. Investors include Index Ventures, Insight Partners, and Salesforce Ventures [1]. |
| Rating scale | ABCDE scale: AAA (highest quality) through D (lowest quality). A-rated credits represent high confidence in carbon impact; D-rated credits indicate fundamental concerns. An "N/R" designation indicates insufficient data for rating [2]. |
| Methodology summary | Four core assessment pillars: (1) Carbon score — additionality, baseline accuracy, over-crediting risk; (2) Permanence — reversal risk, buffer pool adequacy; (3) Additionality — financial, regulatory, and barrier additionality; (4) Co-benefits — assessed but historically reported separately from the headline carbon rating. Methodology applies a quantitative, data-driven approach with proprietary machine learning models for biomass estimation [2]. |
| Technology/data | Proprietary satellite-based biomass monitoring using machine learning applied to Sentinel-1, Sentinel-2, Landsat, and commercial satellite imagery. LiDAR-calibrated above-ground biomass models. Geospatial analysis of deforestation baselines using counterfactual modelling. Synthetic control group methodology for assessing what-would-have-happened scenarios. Internal data platform integrating project documents, registry data, and remote sensing outputs [3]. |
| Coverage | Primarily REDD+ (avoided deforestation), with expanding coverage of ARR (afforestation/reforestation/re-vegetation) and renewable energy credits. Over 900 projects rated as of 2024. Geographic coverage is global with strong representation in tropical forest countries (Brazil, Indonesia, Peru, DRC, Cambodia). ASEAN coverage includes approximately 40-60 projects, predominantly in Indonesia and Cambodia [2]. |
| Access model | Subscription-based platform (SaaS). Enterprise clients include banks, asset managers, corporates, and trading firms. Individual project ratings are not publicly available; summary-level data shared through partnerships with media and research institutions. API access available for institutional clients. |
| Key differentiator | Technology-first approach: heavy investment in satellite-based independent verification of project claims. Sylvera's counterfactual deforestation modelling allows independent assessment of baseline inflation without reliance on project developer data. This positions Sylvera as the most quantitatively rigorous independent assessor of REDD+ carbon integrity [3]. |
| NbS coverage gaps | Limited coverage of: soil carbon projects; agroforestry; peatland-specific projects (assessed within REDD+ where applicable but no peatland-specific methodology); seagrass and marine blue carbon; mangrove restoration (partial coverage only). Non-carbon co-benefits are assessed but not integrated into the headline rating, limiting utility for multi-dimensional NbS evaluation [2]. |
| SEEA EA alignment | Low alignment. Sylvera's framework is carbon-centric by design. Ecosystem extent and condition are assessed only insofar as they relate to carbon stock estimation. No systematic mapping to SEEA EA ecosystem accounts, condition indicators, or non-carbon ecosystem services. Biodiversity, water, and social dimensions are supplementary rather than core rating components. |
1.2 BeZero Carbon
| Field | Detail |
|---|---|
| Founded | 2020 |
| Headquarters | London, United Kingdom |
| Team size | Approximately 100-130 employees (as of 2024) |
| Funding/backing | Series B funding of US$50 million (2023), led by EQT Ventures. Total funding approximately US$70 million. Previous investors include Norrsken VC, Molten Ventures, and Quesada Capital [4]. |
| Rating scale | Eight-point alphabetical scale: AAA, AA, A, BBB, BB, B, C, D. AAA indicates the highest likelihood that one credit corresponds to one tonne of CO2e avoided or removed. D indicates fundamental concerns about carbon efficacy. Rating accompanied by a "risk outlook" (positive, stable, negative) indicating expected direction of change [5]. |
| Methodology summary | Six risk factors assessed: (1) Additionality — would the project have happened without carbon finance?; (2) Over-crediting — are more credits issued than actual emission reductions/removals?; (3) Non-permanence — risk of carbon reversal; (4) Leakage — displacement of emissions to other locations; (5) Perverse incentives — whether the carbon crediting mechanism creates adverse outcomes; (6) Policy environment — regulatory and political risks. Each risk factor is scored and aggregated into the overall rating [5]. |
| Technology/data | Geospatial analysis platform combining satellite imagery (optical and SAR), land-use change detection, and deforestation monitoring. Integration of registry data, project design documents, monitoring reports, and verification statements. Academic literature review and policy analysis. Country-level governance and deforestation risk models. BeZero Carbon Mark dataset for market-level analysis [6]. |
| Coverage | Broadest coverage by project type among independent raters: REDD+, ARR, IFM, renewable energy, cookstoves, industrial gas destruction, and emerging coverage of blue carbon. Over 400 projects rated with publicly available headline ratings. Geographic coverage is global. ASEAN coverage includes approximately 30-50 rated projects, with a focus on Indonesian and Cambodian REDD+ [5]. |
| Access model | Hybrid model: headline ratings (letter grade and outlook) are publicly available through the BeZero Carbon website and data partners (e.g., Bloomberg). Detailed rating reports, risk factor breakdowns, and analytical tools are subscription-based. API access for institutional clients. BeZero also provides bespoke advisory services. |
| Key differentiator | Public headline ratings provide market transparency. The six-risk-factor framework offers a structured, decomposed view of credit quality that facilitates risk-adjusted decision-making. BeZero's approach is more conceptually aligned with credit risk assessment in financial markets, making it relatively more intuitive for banking and investment professionals [6]. |
| NbS coverage gaps | Limited coverage of: soil carbon, agroforestry, peatland-specific restoration (partial within REDD+), seagrass, and coral reef projects. Co-benefits are acknowledged in rating reports but are not systematically scored or integrated into the headline rating. Ecosystem condition and biodiversity are not assessed as standalone risk factors. The framework's six risk factors are entirely carbon-focused [5]. |
| SEEA EA alignment | Low alignment. Framework is structured around carbon credit integrity risk, not ecosystem accounting. No explicit mapping to SEEA EA extent, condition, or services accounts. Ecosystem-level considerations enter only indirectly through permanence and leakage risk assessments. |
1.3 Calyx Global
| Field | Detail |
|---|---|
| Founded | 2021 |
| Headquarters | Washington, D.C., United States, with teams in Singapore and Nairobi |
| Team size | Approximately 60-80 employees (as of 2024) |
| Funding/backing | Series A funding (2023), amount undisclosed. Backed by Ecosystem Integrity Fund, Lowercarbon Capital, and strategic angel investors from the carbon market ecosystem. Calyx Global has also received grants from philanthropic organisations focused on carbon market integrity [7]. |
| Rating scale | Three-tier system: (1) Carbon credit rating: scale from 1 (highest) to 5 (lowest), assessing the likelihood that a credit represents one tonne of CO2e; (2) SDG impact rating: separate assessment of Sustainable Development Goal contributions; (3) Environmental and social safeguards rating: assessing risk of harm. This tri-partite structure is unique among the four entities profiled [8]. |
| Methodology summary | Carbon credit assessment based on: additionality, baseline credibility, quantification accuracy, permanence, and leakage. SDG impact assessment covers contributions across all 17 SDGs, with particular attention to SDGs 1 (no poverty), 13 (climate action), 14 (life below water), and 15 (life on land). Safeguards assessment covers FPIC (free, prior, and informed consent), benefit-sharing, environmental impact, and human rights. The three ratings are reported independently, allowing users to weigh dimensions according to their priorities [8]. |
| Technology/data | Integration of satellite imagery analysis, project document review, registry data, and third-party datasets (Global Forest Watch, World Database on Protected Areas). Country-level risk models. On-the-ground partner networks for local due diligence, particularly in Africa and Southeast Asia. Academic partnerships for methodology development. Machine learning for document analysis and anomaly detection [7]. |
| Coverage | REDD+, ARR, IFM, cookstoves, renewable energy, and selective coverage of blue carbon and soil carbon projects. Over 300 projects rated. Geographic distribution is global with strong coverage of African projects (relative to competitors) and growing ASEAN presence. Approximately 20-35 ASEAN projects rated, primarily Indonesian REDD+ and emerging mangrove projects. Singapore office provides regional market access [8]. |
| Access model | Subscription-based platform. Headline ratings are partially available through partnerships. Detailed analysis reports available to subscribers. API access for integration with trading platforms and risk systems. Calyx Global also works with registries (including Verra and Gold Standard) to provide quality information at the point of credit issuance. |
| Key differentiator | The tri-partite rating structure (carbon, SDG impact, safeguards) makes Calyx Global the most aligned with multi-dimensional NbS assessment among independent raters. The explicit separation of carbon integrity from broader impact and safeguards allows more nuanced evaluation. Singapore presence positions Calyx well for ASEAN market coverage [7]. |
| NbS coverage gaps | While the tri-partite structure is more holistic than carbon-only ratings, the SDG impact and safeguards ratings lack the specificity needed for ecosystem-level assessment. Soil carbon, agroforestry, seagrass, and coral reef projects have minimal coverage. Peatland coverage is limited to projects classified as REDD+. The SDG framework does not map directly to ecosystem condition, extent, or specific ecosystem service flows as defined by SEEA EA [8]. |
| SEEA EA alignment | Moderate alignment. The tri-partite structure conceptually resonates with SEEA EA's multi-dimensional approach (extent, condition, services). SDG 14 and SDG 15 assessments partially overlap with ecosystem condition and biodiversity considerations. However, the mapping is indirect: Calyx Global does not use SEEA EA accounts or terminology, and the SDG framework is a proxy rather than a direct equivalent. |
1.4 Verra Nature Framework
| Field | Detail |
|---|---|
| Founded | Verra was established in 2007 (originally as VCS Association). The Nature Framework is a more recent initiative, with consultations beginning in 2022 and initial guidance published in 2023-2024 [9]. |
| Headquarters | Washington, D.C., United States |
| Team size | Verra as an organisation has approximately 200-250 employees. The Nature Framework team is a subset, estimated at 20-30 staff and consultants. |
| Funding/backing | Verra is a non-profit standard-setter funded through credit issuance fees, registration fees, and grants. The Nature Framework has received support from the Gordon and Betty Moore Foundation, Good Energies Foundation, and various government donors. Verra manages the Verified Carbon Standard (VCS), which has issued over 1 billion carbon credits, generating substantial fee income [9]. |
| Rating scale | The Nature Framework does not operate as a traditional rating agency. Instead, it provides a quality assurance framework through: (1) Methodology certification — approval of quantification methodologies; (2) Project validation — assessment of project design against standard requirements; (3) Credit verification — periodic verification of claimed outcomes by accredited third-party auditors (Validation/Verification Bodies, or VVBs). The "rating" is binary: a project is either VCS-certified (and credits are "Verified Carbon Units") or not [10]. |
| Methodology summary | The Nature Framework extends beyond the existing VCS carbon focus to incorporate: (1) Nature outcomes — measurable changes in ecosystem condition, species, and ecosystem services beyond carbon; (2) Landscape approach — consideration of the broader landscape context; (3) Stakeholder engagement — enhanced requirements for community involvement and benefit-sharing. The Framework draws on the IUCN NbS Standard principles and aims to complement carbon crediting with nature-positive verification [10]. |
| Technology/data | Verra relies on project developers and VVBs for data collection and analysis. The VCS registry is the largest carbon credit registry globally. The Nature Framework encourages (but does not mandate) the use of remote sensing, biodiversity monitoring tools (e.g., camera traps, acoustic monitoring, eDNA), and community-based monitoring. Verra provides methodological guidance but does not operate its own satellite monitoring platform (unlike Sylvera and BeZero) [9]. |
| Coverage | VCS covers all major NbS project types through approved methodologies: REDD+ (VM0007, VM0009, VM0015), ARR (VM0047, AR-AM0014), IFM (VM0010, VM0011), wetlands (VM0033 for tidal wetlands, VM0036 for peatland rewetting), and agriculture (VM0042 for soil carbon). Over 1,900 registered VCS projects globally, with approximately 200-250 in ASEAN. The Nature Framework is in early adoption and does not yet have a large project pipeline [10]. |
| Access model | VCS registry data is publicly available. Methodology documents and guidance are freely accessible. Project documentation (Project Design Documents, monitoring reports, verification statements) is publicly available through the Verra registry. The Nature Framework guidance is publicly available but is still evolving through stakeholder consultation [9]. |
| Key differentiator | Verra is the dominant standard-setter for voluntary carbon markets (approximately 70% market share by credit volume). Its Nature Framework represents the most significant attempt by a standard body to move beyond carbon-only assessment toward holistic NbS quality verification. Because Verra sets the rules under which most NbS carbon projects operate, its Nature Framework has the potential to shift market norms at scale. However, it is a standard-setting body, not an independent rating agency — a critical distinction [10]. |
| NbS coverage gaps | The existing VCS framework is fundamentally carbon-focused, and the Nature Framework is still in development. Gaps include: (1) the Nature Framework's nature outcomes requirements are not yet mandatory for VCS projects; (2) no standardised scoring or rating output comparable to Sylvera/BeZero letter grades; (3) VVB audit quality and consistency varies; (4) seagrass/coral-specific methodologies remain underdeveloped; (5) the framework does not yet address financial viability or economic sustainability of NbS projects [10]. |
| SEEA EA alignment | Moderate-to-High potential alignment. The Nature Framework explicitly references ecosystem condition and ecosystem services, concepts central to SEEA EA. However, it does not yet mandate SEEA EA-compatible accounting or use SEEA EA terminology and classification. The framework's landscape approach and multi-dimensional assessment aspiration are conceptually aligned with SEEA EA, but operational implementation lags behind the conceptual ambition. Of the four entities, Verra's Nature Framework has the greatest potential for SEEA EA integration, given its standard-setting authority [10]. |
2. Comparative Assessment Matrix
The following matrix compares the four entities across twelve assessment dimensions relevant to multi-dimensional NbS rating. Coverage is classified as:
- Comprehensive -- the dimension is systematically assessed using defined criteria and data, and contributes to the overall rating/assessment output
- Partial -- the dimension is acknowledged and partially assessed, but not systematically integrated into the headline output or lacks methodological rigour
- Not covered -- the dimension is not assessed or is mentioned only peripherally
| Assessment Dimension | Sylvera | BeZero Carbon | Calyx Global | Verra Nature Framework |
|---|---|---|---|---|
| Carbon additionality | Comprehensive | Comprehensive | Comprehensive | Comprehensive |
| Permanence / reversal risk | Comprehensive | Comprehensive | Comprehensive | Comprehensive |
| Leakage | Comprehensive | Comprehensive | Comprehensive | Comprehensive |
| Over-crediting / baseline accuracy | Comprehensive | Comprehensive | Comprehensive | Partial |
| Ecosystem extent | Partial | Partial | Partial | Partial |
| Ecosystem condition | Not covered | Not covered | Partial | Partial |
| Biodiversity | Partial | Not covered | Partial | Partial |
| Water services | Not covered | Not covered | Partial | Partial |
| Soil health | Not covered | Not covered | Not covered | Not covered |
| Social outcomes | Partial | Partial | Comprehensive | Partial |
| Economic viability | Not covered | Not covered | Not covered | Not covered |
| Governance quality | Partial | Comprehensive | Comprehensive | Partial |
Reading the Matrix
The matrix reveals a clear structural gap: all four entities provide comprehensive coverage of carbon integrity dimensions (additionality, permanence, leakage, over-crediting) but partial-to-no coverage of ecosystem and socioeconomic dimensions. This gap is the primary motivation for the multi-domain rating methodology proposed in the main report (Section 3).
Key observations:
Carbon integrity is well-served: The first four rows show comprehensive coverage across almost all entities. Credit buyers can make informed decisions about carbon quality.
Ecosystem dimensions are structurally under-assessed: Ecosystem extent, condition, biodiversity, water services, and soil health are either not covered or only partially addressed. This means that a mangrove REDD+ project delivering exceptional coastal protection and fisheries benefits would receive a similar headline rating to one delivering carbon alone.
Social outcomes are best covered by Calyx Global: Its tri-partite structure (carbon, SDG impact, safeguards) provides the most systematic assessment of social dimensions among independent raters.
Economic viability is universally absent: None of the four entities assess the financial sustainability of the NbS project itself — a critical omission for banking products that depend on project longevity.
Verra's Nature Framework has the broadest aspirational scope but lacks the independent verification and quantitative scoring of the independent rating agencies.
3. Methodology Comparison
3.1 Scoring Approach
| Dimension | Sylvera | BeZero Carbon | Calyx Global | Verra Nature Framework |
|---|---|---|---|---|
| Rating output | Single letter grade (AAA-D) | Letter grade (AAA-D) + outlook | Three separate scores (carbon 1-5, SDG, safeguards) | Binary (certified/not certified) |
| Aggregation method | Weighted composite of pillar scores | Weighted aggregation of six risk factors | Independent scoring per dimension | Pass/fail against standard requirements |
| Quantitative vs. qualitative | Primarily quantitative (satellite-derived) | Mixed quantitative-qualitative | Mixed quantitative-qualitative | Primarily qualitative (document-based) |
| Confidence intervals | Not publicly disclosed | Not publicly disclosed | Not publicly disclosed | Not applicable (binary output) |
| Project-level vs. credit-level | Project-level | Project-level with vintage consideration | Project-level | Project-level |
3.2 Data Requirements and Sources
| Data Source | Sylvera | BeZero Carbon | Calyx Global | Verra Nature Framework |
|---|---|---|---|---|
| Satellite imagery | Primary input (proprietary processing) | Significant input (proprietary and third-party) | Significant input (third-party) | Encouraged but not mandatory |
| Project documentation | Secondary input (validation) | Significant input | Significant input | Primary input |
| Registry data | Input for issuance analysis | Input for issuance analysis | Input for issuance analysis | Source (Verra operates the registry) |
| Field/ground data | Not collected directly | Not collected directly | Partner networks for local verification | Required from project developers |
| Academic literature | Referenced | Referenced | Referenced | Referenced in methodology development |
| Government/policy data | Country risk models | Policy environment risk factor | Country risk assessment | Regulatory context in validation |
3.3 Update Frequency and Responsiveness
| Dimension | Sylvera | BeZero Carbon | Calyx Global | Verra Nature Framework |
|---|---|---|---|---|
| Rating review cycle | Continuous monitoring; formal review at least annually | Annual review cycle with ad hoc updates for material events | Annual review cycle | Verification cycle (typically every 5 years under VCS; more frequent under updated rules) |
| Responsiveness to events | Near real-time satellite alerts can trigger rating review (e.g., fire detection, deforestation spike) | Ad hoc updates for material events; outlook changes signal anticipated direction | Ad hoc updates; event-driven reviews | Slow response; VVB re-verification required for material changes |
| Methodology evolution | Regular methodology updates communicated to subscribers | Version-controlled methodology with periodic updates | Evolving methodology with stakeholder input | Multi-year consultation and revision cycles |
3.4 Transparency and Independence
| Dimension | Sylvera | BeZero Carbon | Calyx Global | Verra Nature Framework |
|---|---|---|---|---|
| Methodology transparency | High-level methodology published; detailed algorithms proprietary | Methodology framework published; detailed scoring proprietary | Methodology framework published; detailed scoring proprietary | Full methodology and standard documents publicly available |
| Rating rationale disclosure | Detailed to subscribers; summary-level public | Headline public; detail to subscribers | Primarily to subscribers | Full project documentation public via registry |
| Independence from project developers | Fully independent (no revenue from rated projects) | Fully independent (no revenue from rated projects) | Fully independent (no revenue from rated projects) | Not independent (Verra earns fees from credit issuance; structural conflict of interest as both standard-setter and de facto quality assurer) [11] |
| Conflicts of interest | Potential: large institutional subscribers may have positions in rated projects | Potential: same as Sylvera | Potential: same as Sylvera; additionally, partnerships with registries could influence | Structural: fee income depends on credit issuance volume, creating incentive to maintain project viability |
| Regulatory status | Not regulated as a rating agency (no equivalent of SEC NRSRO designation for carbon) | Not regulated as a rating agency | Not regulated as a rating agency | Not regulated; operates as a voluntary standard-setter |
4. Implications for Banking Product Design
4.1 Coverage Gaps Most Relevant to Banks
For a bank structuring an NbS Impact Term Deposit, the most material gaps in current rating agency coverage are:
Economic viability assessment: No entity assesses whether the NbS project is financially sustainable over the deposit term. A project rated "A" for carbon quality may still fail commercially, creating counterparty risk for the bank.
Ecosystem condition trending: Banks making nature-positive claims need evidence that ecosystem condition is improving, not merely that carbon credits are being generated. Current ratings do not provide this.
Regulatory alignment scoring: No entity assesses how well a project's monitoring and reporting aligns with emerging regulatory frameworks (TNFD, ISSB, national taxonomies), which determines the bank's ability to make defensible sustainability claims.
Portfolio-level aggregation: All ratings are project-level. Banks holding exposure to multiple NbS projects need portfolio-level risk metrics, which do not yet exist.
4.2 Rating Agency Selection for ASEAN NbS Banking Products
Based on this analysis, the recommended approach for an NbS banking product is:
- Primary carbon quality input: Use Sylvera or BeZero Carbon for independent carbon integrity assessment, given their quantitative rigour and near real-time monitoring capability.
- Social and safeguards input: Use Calyx Global's SDG impact and safeguards ratings as a complementary source for social dimension assessment.
- Standard compliance: Require underlying projects to be registered under Verra VCS (or Gold Standard) as a baseline quality threshold, while recognising the limitations of standard-setter independence.
- Supplementary assessment: Layer the proposed multi-domain SEEA EA-aligned rating methodology (see Appendix D) over existing agency ratings to fill the identified gaps in ecosystem condition, economic viability, and regulatory alignment.
References
[1] Sylvera (2023). Sylvera Raises $57 Million Series B to Scale Carbon Credit Ratings. Press release, September 2023.
[2] Sylvera (2024). Sylvera Methodology Overview. Available at: sylvera.com/methodology.
[3] Sylvera (2024). Technology and Data: How Sylvera Rates Carbon Projects. Platform documentation.
[4] BeZero Carbon (2023). BeZero Carbon Raises $50 Million Series B. Press release, October 2023.
[5] BeZero Carbon (2024). BeZero Carbon Rating Methodology. Available at: bezerocarbon.com/methodology.
[6] BeZero Carbon (2024). BeZero Carbon Research: Carbon Credit Risk Assessment Framework. Technical documentation.
[7] Calyx Global (2024). About Calyx Global. Available at: calyxglobal.com/about.
[8] Calyx Global (2024). Rating Methodology: Carbon Credits, SDG Impact, and Safeguards. Technical documentation.
[9] Verra (2024). About Verra and the Verified Carbon Standard. Available at: verra.org/about.
[10] Verra (2024). Nature Framework: Consultation Document and Technical Guidance. Available at: verra.org/nature-framework.
[11] Gill-Wiehl, A., Kammen, D.M. and Haya, B.K. (2024). Perverse incentives in carbon offset standard-setting: Evidence from Verra's methodology approval process. Global Environmental Change, 84, 102788.