Getting Scope 3 Data Ready (2025): GHG Protocol vs SBTi requirements explained

---## TL;DRGHG Protocol is the accounting rulebook for building a complete, consistent Scope 3 inventory. SBTi evaluates your targets and coverage and expects credible methods and documentation. Get "report-ready" by mapping categories, choosing methods (spend → activity → supplier specific), version locking factors, and writing a short methods memo. Get "SBTi-ready" by demonstrating coverage of most Scope 3 emissions, showing an upgrade plan to better data, and implementing governance (QA + recalculation policy).---## 1) GHG Protocol vs SBTi: who asks for what?| Topic | GHG Protocol (what you must account) | SBTi (what they check) || ---------------- | ---------------------------------------------------------------------------— | --------------------------------------------------------------------------------------------------------------------- || Purpose | Standard for measuring & reporting GHG emissions | Framework for validating targets & ambition || Scope 3 coverage | Identify relevant categories and estimate using accepted methods | Evidence that your target covers most Scope 3 emissions (often ~two-thirds) and is aligned with ambition criteria || Methods | Spend-, activity-, supplier specific methods are acceptable with transparency | Preference for higher quality data where material; clear plan to upgrade methods over time || Documentation | Organizational/operational boundaries, factors, assumptions, QA | Target statement, coverage calculation, governance, recalculation triggers |---## 2) The Scope 3 data-readiness ladder| Level | Method | When to use | Strengths | Watchouts || --------- | ------------------------------- | --------------------------------------------- | ---------------------------------------— | ---------------------------------------------- || L1 | Spend based | Rapid coverage; long-tail suppliers/materials | Fast to implement; good for screening | Sensitive to price/inflation; coarse precision || L2 | Activity based | Material lanes/processes (ton-km, kWh, mass) | Better physics linkage; track initiatives | Needs operational data; unit conversions || L3 | Supplier specific | Top emitters or strategic suppliers | Highest relevance; ties to real change | Verification & consistency; data sharing || L4 | Verified initiative impacts | Recycled content, RE purchases, mode shifts | Direct line to reductions | Double counting; ensure boundary alignment |Rule of thumb: Start L1 for coverage, then move material categories to L2/L3, and attribute savings at L4.---## 3) Category-by-category data map (minimums vs strong practice)| Cat. | Name | Minimum for Protocol | Strong for SBTi review || ------— | ---------------------------------— | --------------------------------------- | ------------------------------------------------------------------— || 1 | Purchased Goods & Services | AP/GL mapped to sectors + spend factors | Activity data for top SKUs; supplier specific factors where feasible || 2 | Capital Goods | CapEx mapped to sector factors | BOM/activity for large projects; project EPDs || 3 | Fuel & Energy-related (not in S1/2) | Energy bills + upstream factors | Site-level splits; supplier residual mixes || 4 | Upstream Transport & Distribution | Mode/distance assumptions or 3PL spend | Ton-km by lane & mode; carrier energy mix || 5 | Waste | Volumes by stream + waste factors | Vendor tickets; % treatment verified || 6 | Business Travel | TMC export (mode, class) | Class splits verified; rail & hotel factors by region || 7 | Employee Commuting/WFH | Survey or HR-based splits | Geo-specific modal factors; WFH energy method || 9 | Downstream T&D | Mode/distance assumptions | Distributor data; temperature-control impacts || 11 | Use of Sold Products | Duty-cycle model & lifetime | Field performance data; regionalized electricity || 12 | End-of-Life of Products | Material composition + disposal splits | Verified recycling rates; EPR data || 15 | Investments | Applicable financed-emissions method | Data quality tiers; attribution evidence |---## 4) Data inventory (copy-paste table)| Data domain | Source system(s) | Owner | Coverage % | *Method (A/S/SS\) | Factor library & vintage | Known gaps | Fix plan & ETA || --------------- | ------------------— | ---------- | ------------— | --------------------- | ---------------------------- | ---------------— | ------------------ || AP/GL (Cat.1) | ERP/AP | Finance | | S/SS | | Supplier splits | || Logistics | 3PL portals | Ops | | A/SS | | Lane gaps | || Energy upstream | Utility, EMS | Facilities | | A | | Regional vintages | || Travel | TMC | Finance | | A | | Class splits | || WFH/Commuting | HR/Survey | HR | | A | | Survey cadence | || Use phase | Product/Eng | Product | | A/SS | | Duty cycle | |- A = Activity based, S = Spend based, SS = Supplier specific---## 5) Factor governance (register template)| Category / source | Factor library | Code/name | Geography | Vintage (year) | Unit | Notes || --------------------- | ------------------ | ---------------------------- | ---------------- | ------------------ | ------------- | ---------------------- || Cat.1 sector fallback | [IO vX.Y] | [Sector code] | [Region] | 20XX | kgCO₂e/$ | Currency deflator used || Electricity (LB) | [Grid mix vX.Y] | [Code] | [Country/Region] | 20XX | kgCO₂e/kWh | || Electricity (MB) | [Market vX.Y] | [Residual mix / supplier EF] | | 20XX | kgCO₂e/kWh | Certificate criteria || Logistics | [LCA vX.Y] | [Mode x distance] | | 20XX | kgCO₂e/ton-km | || Supplier specific | [Supplier doc] | [ID] | [Plant] | 20XX | kgCO₂e/unit | Verification status |Good practice: Version-lock the factor pack used in the baseline; document any mid-year substitutions.---## 6) Methods & assumptions memo (skeleton)1. Organizational & operational boundaries2. Category methods (S/A/SS), with double-count controls3. Electricity details (LB & MB; certificate criteria)4. Factor libraries (names, regions, vintages; version IDs)5. Data gaps & proxies (what/why; replacement plan & dates)6. QA rules (outliers; intensity benchmarks vs peers/priors)7. Recalculation triggers & thresholds---## 7) QA rules you can adopt today- Completeness: Every relevant Scope 3 category decisioned (Included/Not relevant) with rationale.- Double counting: Cat.3 vs Scope 1/2; Cat.1 vs Cat.2; Cat.4/9 vs internal logistics.- Factor sanity: Single geography & vintage per category unless justified.- Outliers: Flag site/category ±>30% YoY for investigation.- Intensity checks: tCO₂e per revenue/unit/FTE vs prior year and peer range.- Traceability: Data lineage from source system → transform → factor → result.- Lock & label: Factor pack/version and memo version are stamped in outputs.---## 8) Common edge cases (and answers)- Price inflation breaks spend factors → Deflate to baseline currency year; prioritize activity data in hot-spots.- Mixed geographies → Use weighted regional factors or split the population; avoid global averages for regionalized categories.- Certificates (market based electricity) → Define quality criteria (geography match, vintage, additionality) and disclose scope of application.- WFH allocation → Apply a simple kWh/day assumption with regional emission factors; document survey cadence.- Partial supplier data → Combine SS data for top suppliers with L1/L2 for the long tail; label methods clearly.- PPAs/RECs timing → Align procurement period with reporting period; avoid double counting across entities.---## 9) Recalculation policy (Scope 3 data changes)**Triggers- Structural changes (M and A, outsourcing/insourcing) affecting Scope 3 boundary- Factor/method updates that would materially shift base year totals- Material data corrections- Discovery of misclassification (e.g., Cat.1 vs Cat.2)Materiality thresholds- Relative: ≥ 5 to 10% change to base year total- Absolute: ≥ [X,000] tCO₂eChange log (copy-paste)| Date | Trigger | Estimated impact (% / tCO₂e) | Decision | Approvers | Notes || ------— | ---------— | ------------------------------— | ---------------- | ------------- | --------- || | | | Recalculate / No | | |---## 10) Supplier primary-data request template (if you aren't using DitchCarbon)> Subject: Request for primary emissions data & climate target status>> Hello [Name],>> We're improving the quality of our Scope 3 inventory. Please share:1. Your latest Scopes 1 to 3 inventory (base year, methods, and factor sources).2. Any plant- or product-level emission factors relevant to our purchases.3. Your science-based target status (committed/validated) and evidence link.> We will attribute reductions from verified initiatives (e.g., recycled content, renewable energy, logistics mode shift). Thank you.---## 11) Ready-to-paste reporting blocksScope 3 coverage statement (example)> [list], [~≥ two-thirds]Electricity disclosure (Scope 2) for context> both---## 12) FAQs (brief)Do I need supplier specific data for all suppliers? No, focus on material suppliers first; maintain coverage in the long tail with spend/activity methods.Can I submit targets with spend based data? Yes, if you show credible coverage and an upgrade plan for material categories.What about FLAG? If land-sector emissions are material in your value chain, prepare separate FLAG accounting and targets.---## How DitchCarbon helps- No need to send supplier surveys: Know the status of all your suppliers with no need for manual work.- Coverage → precision: Map AP/GL for rapid Scope 3 coverage, then guide upgrades to activity- and supplier specific data where it matters most.- Version-locked factor packs: Region-aware libraries with vintages and provenance; clean audit trails in exports.- Supplier workflows: Collect primary data, track SBT commitment/validation, and attribute verified initiative impacts to categories.- Governance built-in: QA rules, outlier flags, and a baseline/target change log aligned to materiality thresholds.- SBTi-ready outputs: Paste-ready boundary statements, methods memos, factor registers, and coverage summaries for internal review or external assurance.