CarbonLedger — Scope 1+2+3 Emissions Ledger
20 emission sources spanning Scope 1 (gas + fleet + refrigerant leakage), Scope 2 (location-based AND market-based per dual-reporting rule), Scope 3 (purchased goods, business travel, employee commute, use-of-sold-products at 280 tCO₂e, financed-emissions). Per-source: GHG-Protocol-aligned methodology, FY24 actuals vs FY22 baseline, SBTi 1.5°C-aligned 2030 target.
What it is
The shape behind every corporate carbon-accounting platform — Watershed, Persefoni, Sweep, Greenly. GHG-Protocol-aligned register with the dual-reporting Scope 2 rule, the 280 tCO₂e Scope 3.11 “use of sold products” finding (the largest single category for SaaS), and the SBTi-aligned reduction trajectory.
What’s in it
- 20 emission sources across all 3 scopes:
- Scope 1 — Vancouver + Toronto office gas (42 + 18 tCO₂e), 4-van fleet (24), refrigerant fugitives (8)
- Scope 2 — both location-based (BC Hydro residual 0.0083 kg/kWh) AND market-based (zero with Bullfrog RECs for Vancouver; residual mix for Toronto since no RECs there)
- Scope 3 — AWS compute (84, down 28% YoY via region-shift + AWS PPAs), SaaS spend-based (42), hardware embodied (88), employee commute (62), business-travel flights (142, down 35% via remote-by-default), use-of-sold-products at 280 tCO₂e (largest single line — 28M browser-session-hours × device draw × grid mix), financed emissions (12, MSCI ESG Leaders Index, PCAF methodology)
- Composition bar — Scope 1 / Scope 2 (mkt) / Scope 2 (loc, ref) / Scope 3 share of total.
- Per-source 5-field shape: methodology (activity / spend / hybrid / supplier-specific / modeled / financed-emissions), FY24 actuals, FY22 baseline, YoY change, SBTi 2030 target.
- SBTi 1.5°C linear trajectory — 4.2%/yr reduction = ~34% reduction by 2030.
- CSRD ESRS E1 + CDP disclosure mapping per source — exact cell where this number lands in the corporate disclosure.
Why this shape
GHG Protocol Corporate Standard + Scope 3 Standard are the global baseline. CSRD ESRS E1 (effective FY24 for large EU companies + UK + US-listed) demands the granular per-source disclosure. SBTi Corporate Net-Zero Standard demands the 1.5°C trajectory. Most SaaS teams miss the Scope 3.11 use-of-sold-products number entirely — it’s often the largest emission line and the only one that real product decisions affect (bundle size, CDN, energy-efficient algorithms). CarbonLedger surfaces it.
How it ships
Single HTML file, ~18KB. Zero dependencies. 20 sources × 3 scopes × methodology breakdown + composition bar in 220 lines of vanilla JavaScript.