While different calculators and measuring tools can be used, the first key steps lie in collecting data in a standardised way.
Activity data
· Use primary data if possible
· Fuel use or energy consumption per vehicle/leg is preferred
· Distance, route/leg data (stop‑level/geolocation)
· Vehicle type, engine/fuel type, load/occupancy (payload or vehicle/unit weight)
· Number of orders, stops or transported units (to allocate emissions to orders)
Supplementary data and fallbacks
· Use average/default emission factors (mode and fuel-specific) when primary data is missing
· Vehicle or transport unit dimensions (volume/space metrics for space‑sensitive freight)
· Electricity grid emission factor (for charging) and fuel lifecycle factors if doing life cycle assessment (LCA)
Methodology and allocation rules
· Choice of standard/framework (GLEC/GLAC, ISO 14083/14067, GHG Protocol, ECG guidance, CSRD/ESRS alignment)
· Allocation granularity (stop‑level, leg‑level, per‑vehicle, per‑order) and rules for distributing shared trips (for example, ECU or per‑VIN)
Processing and modelling needs
· Geocoding/route modelling, registry lookups, data cleaning and imputation algorithms (for example, estimate weight from partial data)
· TCO or cost indices if assessing electrification trade‑offs
Transparency and auditability
· Traceability of data sources, documented assumptions, and an audit package or export (ISO‑compliant reports)
· Versioned emission factors and justification for any data corrections
Practical considerations
· Use primary fuel/energy data where possible, as averages/defaults may be 20-40% off
· Harmonise factors and reporting format for regulator/auditor acceptance
· When selling/verifying savings, ensure third‑party validation and auditable book‑and‑claim processes.