A carbon ledger is a structured, auditable record of emissions-relevant activities and calculations, analogous to a financial general ledger. It stores activity data (e.g., fuel consumed, electricity purchased, purchased goods), applied emission factors, calculation methods, units, time/location context, and resulting greenhouse gas (GHG) entries. By capturing data at the transaction or batch level, it enables roll-ups to sites, business units, products, and consolidated enterprise inventories while preserving traceability and version control.
Operationally, a carbon ledger supports key accounting principles—completeness, accuracy, consistency, and transparency—required by assurance standards. It also provides the scaffolding for Scope 1 (direct), Scope 2 (purchased electricity, heat, steam, cooling), and Scope 3 (value chain) categorization, market- vs. location-based electricity accounting, and audit trails for recalculations or factor updates. Integration with ERP, procurement, energy management, and logistics systems reduces manual handling and enhances data quality.
The ledger’s outputs feed disclosures (e.g., CSRD/ESRS E1, IFRS S2), target tracking, internal carbon pricing, and decision support such as marginal abatement cost analysis. Robust governance—roles, controls, and documentation—aligns with ISO 14064-1 requirements for GHG quantification and reporting.
Key Takeaway: A carbon ledger is the auditable backbone for traceable, standards-aligned enterprise GHG accounting and reporting.