What Is Carbon Accounting?
Carbon accounting is the structured process of quantifying greenhouse gas (GHG) emissions across your organization and value chain. It enables enterprises to measure climate impact, comply with disclosure regulations (BRSR, CSRD, SEC), and design decarbonization strategies with credible baselines.
Scopes Explained
Most frameworks follow the GHG Protocol, which divides emissions into three scopes:
Scope 1 — Direct Emissions
- Stationary combustion: boilers, furnaces, gensets
- Mobile combustion: company-owned vehicles, construction equipment
- Fugitive/process: refrigerant leaks (R134a, R410a), SF₆ from switchgear
Scope 2 — Indirect Electricity
Purchased electricity, heat, steam or cooling. Report in two views:
- Location-based: grid-average emission factor
- Market-based: adjusted for PPAs, RECs, green tariffs (disclose instruments and residual mix)
Scope 3 — Value Chain
Often 70–90% of total emissions. Typical material categories:
- Purchased goods & services; capital goods
- Fuel & energy related (not in Scope 1/2)
- Upstream T&D, business travel, commuting
- Use-phase and end-of-life of sold products
Data Hierarchies
- Direct activity data × specific emission factor (best)
- Supplier-specific factors
- Industry averages (e.g., DEFRA, Ecoinvent)
- Spend-based estimates (least preferred)
Sample Calculation (Scope 1)
Diesel consumed: 12,000 litres
Emission factor (DEFRA 2024): 2.54 kg CO₂e / litre
Total = 12,000 × 2.54 / 1,000 = 30.48 tCO₂e
Controls & Assurance
- Versioned emission factors with year, source and region
- Locked reporting periods; reviewer sign-off workflow
- Variance analysis vs prior period and drivers (vol/EF/mix)
- Evidence vault: invoices, meter photos, grid proofs, PPAs/RECs
Next step: start structured data capture with the
BRSR Data Collection Template.