Methodology
The OSW Sustainability Benchmark uses a 100-point core score across three pillars and 15 metrics. External validation is included inside the core score (Metric 15, weight 12); there is no separate add-on. A company cannot reach the Leader band on unverified self-disclosure alone.
1. Three pillars (100 points total)
Future Commitments
30/ 100
Targets and forward growth signal direction of travel; capped at 30% so companies cannot lead on promises alone.
Metrics: 1, 2, 3, 4, 11
Environmental Action
45/ 100
Largest weight, the 'is it actually happening' pillar, with OSW asset-level and emissions-progress evidence concentrated here.
Metrics: 5, 6, 8, 9, 10, 12, 13
Governance & Accountability
25/ 100
Governance is the credibility multiplier: regulatory alignment, supplier due diligence and external assurance.
Metrics: 7, 14, 15
2. The 15 metrics
Weights sum to 100. Pillar = which capability the metric tests.
| # | Metric | Pillar | Weight | Why it matters |
|---|---|---|---|---|
| 1 | Net-zero / carbon-neutrality target | Future Commitments | 7% | Anchors the long-term decarbonisation ambition; SBTi-validation signals credibility. |
| 2 | Interim decarbonisation target | Future Commitments | 7% | Near-term (2030/2035) targets are the strongest test of whether net-zero is bankable. |
| 3 | Scope coverage and Scope 3 inclusion | Future Commitments | 5% | Scope 3 dominates an OSW supply chain; coverage signals reporting maturity. |
| 4 | Renewable / OSW growth commitment | Future Commitments | 7% | Capacity / pipeline target is the core OSW growth signal. |
| 5 | Current emissions intensity | Environmental Action | 7% | Generation intensity (gCO₂/kWh) is directly comparable across utilities. |
| 6 | Absolute emissions progress vs baseline | Environmental Action | 8% | Tests whether decarbonisation is actually being delivered, not just promised. |
| 7 | EU Taxonomy / regulatory alignment | Governance & Accountability | 5% | Taxonomy or equivalent framework alignment shows capital-allocation discipline. |
| 8 | Water and environmental compliance | Environmental Action | 4% | Operational permit and compliance record; flags governance lapses. |
| 9 | Asset-level OSW project evidence | Environmental Action | 10% | Most diagnostic metric for an OSW benchmark, does the company actually deliver projects. |
| 10 | Marine ecology and biodiversity mitigation | Environmental Action | 8% | OSW-specific environmental hotspot (noise, seabirds, benthic impact). |
| 11 | Nature-positive / biodiversity target | Future Commitments | 4% | Forward-looking biodiversity ambition complements the project-level mitigation metric. |
| 12 | Circularity and end-of-life wind asset mgmt | Environmental Action | 4% | Blade recyclability and decommissioning are emerging OSW supply-chain risks. |
| 13 | Low-carbon materials / embodied carbon | Environmental Action | 4% | Steel and concrete embodied carbon is the dominant Scope 3 lever for OSW. |
| 14 | Supplier screening and due diligence | Governance & Accountability | 8% | Critical for OSW customers buying from these companies' supply chains. |
| 15 | External validation, assurance and ratings | Governance & Accountability | 12% | Independent assurance is the credibility multiplier across all other metrics. |
3. From raw evidence to 0–5 scores
Numerical evidence
Maps directly to rubric thresholds (e.g. gCO₂/kWh, % reduction, GW capacity). Quantified disclosure with disclosed baseline scores at the rubric band it lands in.
Qualitative evidence
Scored one band lower than the equivalent quantified statement (e.g. a target without a base year caps at 3). Qualitative-only evidence cannot reach 5.
Project-level evidence
Required to score 4 or 5 on Metrics 9, 10, 12, 13. Group-level policy alone caps these metrics at 3.
External corroboration
External sources (CDP, SBTi, MSCI) may corroborate disclosure but cannot upgrade a missing-disclosure score above 1.
Missing disclosure
Score 0. Do not impute. Recorded as an evidence limitation, not an error.
Avoiding double-counting
Metrics 1, 2 and 6 are orthogonal: ambition vs interim milestone vs delivered reduction. The same disclosure cannot score across all three.
4. Weighted score calculation
Each metric receives a 0–5 score from the rubric. The weighted contribution is:
weighted = (score / 5) × metric_weight
Pillar score = sum of weighted contributions for the metrics in that pillar (max equals the pillar weight). Total score = sum of all 15 weighted contributions (max 100).
5. Score bands
| Range | Tier | Description |
|---|---|---|
| 85–100 | Governance & Accountability | Quantified targets across all pillars, strong asset-level OSW evidence, independently assured. |
| 70–84 | Governance & Accountability | Solid quantification, OSW evidence present, minor gaps in Scope 3 or biodiversity detail. |
| 55–69 | Governance & Accountability | Targets and policies in place, but OSW-specific or supply-chain evidence partial. |
| 40–54 | Governance & Accountability | Mostly Group-level qualitative evidence; OSW asset-level disclosure thin. |
| Below 40 | Governance & Accountability | Material gaps on targets, asset-level evidence and external assurance. |
6. Rubric library (0–5)
Reference rubrics used to translate evidence into scores for each metric.
Metric 1Net-zero / carbon-neutrality targetShow rubricHide
Metric 1
Net-zero / carbon-neutrality target
5
Best practice
SBTi-validated net-zero by ≤2040 covering Scopes 1, 2 and 3 with explicit alignment to 1.5 °C.
4
Strong
Net-zero by ≤2040 covering all three scopes but not yet SBTi-validated, OR SBTi-validated with 2050 horizon.
3
Moderate
Net-zero by 2050 covering Scopes 1+2 and partial Scope 3; trajectory described qualitatively.
2
Weak
Stated net-zero ambition without dated boundary or scope detail.
1
Minimal
Generic 'commitment to net-zero' language only.
0
Not disclosed
No net-zero target disclosed.
Metric 2Interim decarbonisation targetShow rubricHide
Metric 2
Interim decarbonisation target
5
Best practice
Quantified absolute 2030 target validated by SBTi with disclosed baseline and current-year progress.
4
Strong
Quantified 2030 absolute or intensity target with baseline; SBTi alignment claimed but not validated.
3
Moderate
2030 target disclosed but mixes intensity and absolute, or baseline unclear.
2
Weak
Directional 2030 ambition (e.g. 'significant reduction') without numbers.
1
Minimal
Only long-dated (post-2035) targets with no near-term milestone.
0
Not disclosed
No interim target disclosed.
Metric 3Scope coverage and Scope 3 inclusionShow rubricHide
Metric 3
Scope coverage and Scope 3 inclusion
5
Best practice
Scope 1, 2 and full Scope 3 disclosed with category-level breakdown (Cat 1, 3, 11, 15) and methodology notes.
4
Strong
Scope 1, 2 and most material Scope 3 categories disclosed; minor gaps acknowledged.
3
Moderate
Scope 1, 2 and partial Scope 3 (e.g. only Cat 11) disclosed.
2
Weak
Scope 1 and 2 only, Scope 3 acknowledged but not quantified.
1
Minimal
Scope 1 and 2 only, no Scope 3 reference.
0
Not disclosed
No GHG inventory disclosed.
Metric 4Renewable / OSW growth commitmentShow rubricHide
Metric 4
Renewable / OSW growth commitment
5
Best practice
Quantified GW capacity target with dated milestones AND OSW-specific pipeline figures + project list.
4
Strong
Quantified group renewable target with explicit OSW share or OSW pipeline GW.
3
Moderate
Group renewable capacity target without OSW breakdown.
2
Weak
Qualitative 'we are growing renewables / OSW' narrative.
1
Minimal
Token mention of renewables in strategy.
0
Not disclosed
No growth commitment.
Metric 5Current emissions intensityShow rubricHide
Metric 5
Current emissions intensity
5
Best practice
Generation intensity ≤100 gCO₂/kWh disclosed with year-on-year trend and 3rd-party verification.
4
Strong
Intensity 100–200 gCO₂/kWh disclosed with trend.
3
Moderate
Intensity 200–400 gCO₂/kWh disclosed.
2
Weak
Intensity >400 gCO₂/kWh OR intensity disclosed without trend.
1
Minimal
Intensity referenced qualitatively only.
0
Not disclosed
No intensity figure disclosed.
Metric 6Absolute emissions progress vs baselineShow rubricHide
Metric 6
Absolute emissions progress vs baseline
5
Best practice
≥30% absolute Scope 1+2 reduction vs disclosed baseline, third-party verified.
4
Strong
15–30% reduction vs baseline disclosed.
3
Moderate
5–15% reduction OR latest year shows clear downward trend.
2
Weak
Flat or marginal change vs baseline.
1
Minimal
Increase vs baseline acknowledged.
0
Not disclosed
No baseline / progress data.
Metric 7EU Taxonomy / regulatory alignmentShow rubricHide
Metric 7
EU Taxonomy / regulatory alignment
5
Best practice
Disclosed Taxonomy-aligned CapEx, OpEx and revenue % with KPI table (or equivalent regional framework).
4
Strong
Two of three Taxonomy KPIs disclosed, OR equivalent regional alignment (e.g. ASEAN/UK Green Taxonomy) with figures.
3
Moderate
Taxonomy eligibility disclosed, alignment partial.
2
Weak
Reference to Taxonomy without metrics, OR voluntary alignment statement only.
1
Minimal
Mention only.
0
Not disclosed
No reference. (Note: non-EU companies are not penalised; use equivalent regional framework or set baseline at level 3.)
Metric 8Water and environmental complianceShow rubricHide
Metric 8
Water and environmental compliance
5
Best practice
Detailed water-use and environmental-incident KPIs disclosed with zero material non-compliance.
4
Strong
Water KPIs and incident counts disclosed; minor non-compliance addressed.
3
Moderate
Generic compliance statement supported by some KPIs.
2
Weak
Compliance asserted without metrics.
1
Minimal
Non-compliance disclosed without remediation.
0
Not disclosed
No disclosure.
Metric 9Asset-level OSW project evidenceShow rubricHide
Metric 9
Asset-level OSW project evidence
5
Best practice
Multiple operating OSW assets with disclosed MW, ownership %, FID/COD dates, and named sustainability initiatives per project.
4
Strong
Multiple operating OSW assets disclosed with MW and dates; sustainability detail at portfolio level.
3
Moderate
OSW assets disclosed with MW; limited sustainability detail.
2
Weak
OSW projects mentioned without asset-level data.
1
Minimal
OSW pipeline only, no operating assets.
0
Not disclosed
No OSW assets evidenced.
Metric 10Marine ecology and biodiversity mitigationShow rubricHide
Metric 10
Marine ecology and biodiversity mitigation
5
Best practice
Project-level marine mitigation programme: noise abatement (bubble curtains), seabird/marine-mammal monitoring, benthic surveys, post-construction studies, with quantitative outcomes.
4
Strong
Multiple mitigation measures described at project level with some KPIs.
3
Moderate
Mitigation measures described at corporate / policy level with examples.
2
Weak
Generic biodiversity policy referencing OSW.
1
Minimal
Token reference.
0
Not disclosed
No marine-specific evidence.
Metric 11Nature-positive / biodiversity targetShow rubricHide
Metric 11
Nature-positive / biodiversity target
5
Best practice
Time-bound nature-positive / no-net-loss target with biodiversity KPIs and external partnerships.
4
Strong
Biodiversity target disclosed without full KPI set.
3
Moderate
Biodiversity ambition stated, partial KPIs.
2
Weak
Generic biodiversity commitment.
1
Minimal
Token mention.
0
Not disclosed
No target.
Metric 12Circularity and end-of-life wind asset mgmtShow rubricHide
Metric 12
Circularity and end-of-life wind asset mgmt
5
Best practice
Disclosed blade-recycling commitment + landfill-ban policy + reuse/recycling KPIs at asset level.
4
Strong
Group circularity policy with OSW-specific examples and partial KPIs.
3
Moderate
Circularity policy referencing OSW; limited KPIs.
2
Weak
General circular-economy language.
1
Minimal
Token mention.
0
Not disclosed
No disclosure.
Metric 13Low-carbon materials / embodied carbonShow rubricHide
Metric 13
Low-carbon materials / embodied carbon
5
Best practice
Quantified low-carbon steel / green concrete procurement with supplier names and embodied-carbon KPI per project.
4
Strong
Low-carbon material initiatives disclosed with examples and partial KPIs.
3
Moderate
Embodied-carbon discussed with one or two project examples.
2
Weak
General reference to low-carbon materials.
1
Minimal
Token mention.
0
Not disclosed
No disclosure.
Metric 14Supplier screening and due diligenceShow rubricHide
Metric 14
Supplier screening and due diligence
5
Best practice
Documented supplier code, ESG due diligence, audit programme with coverage % and outcomes; OSW-tier-1 suppliers named.
4
Strong
Supplier code + due-diligence framework with KPIs but no OSW-specific tiering.
3
Moderate
Supplier code disclosed; due-diligence narrative without KPIs.
2
Weak
Reference to supplier expectations only.
1
Minimal
Token mention.
0
Not disclosed
No supplier framework.
Metric 15External validation, assurance and ratingsShow rubricHide
Metric 15
External validation, assurance and ratings
5
Best practice
Independent assurance (limited or reasonable) of GHG + sustainability data PLUS strong external rating (e.g. CDP A, MSCI AAA/AA, SBTi-validated).
4
Strong
Independent assurance + at least one strong external rating.
3
Moderate
Either assurance OR strong rating.
2
Weak
Self-declared alignment with frameworks (GRI, TCFD) without assurance.
1
Minimal
Token reference to standards.
0
Not disclosed
No external validation.