Car
Calculate car travel emissions on the Calculation API with one of the car methodologies below. They differ mainly in how you describe the vehicle: a rental car class, a vehicle model, or your own emission figure.
Choose a methodology
| Methodology | Coverage | Basis | Inputs you need | Notes |
|---|---|---|---|---|
| ACRISS | Not stated | ACRISS Environmental Responsibility & CO2 Emissions Guidelines | origin and destination, distance_in_km or number_of_days; optional acriss_car_type (or sipp_car_type or pseudo_car_type), fuel_type | Rental car classes; covers EVs, HEVs and PHEVs |
| BASIC | Not stated | Your own intensity; fuel factors from the GLEC Framework | origin and destination, distance_in_km or number_of_days; plus co2_grams_per_km, or consumption_per_100_km with fuel_type | No defaults or inferred vehicle classes: it uses exactly what you send |
| DEFRA 🇬🇧 | Not stated | UK government DEFRA Conversion Factors | origin and destination, distance_in_km or number_of_days; optional car_type (or acriss_car_type or sipp_car_type), fuel_type, energy_scope, methodology_version | Pin a factor year with methodology_version |
| EEA 🇪🇺 | Not stated | European Environment Agency passenger car CO₂ monitoring | origin and destination, distance_in_km or number_of_days; optional manufacturer, model, model_year, fuel_type, engine data | Look up valid vehicle values in the EU-EEA database |
| EPA 🇺🇸 | Not stated | US EPA (FuelEconomy.gov, GHG Emission Factors Hub) | origin and destination, distance_in_km or number_of_days; optional manufacturer, model, model_year, fuel_type, epa_vehicle_size_class, engine data | Look up valid vehicle values in the US-EPA database |
Every methodology above supports audit mode. All of them take the distance from distance_in_km first, then origin and destination, then estimate it as 60 km per day from number_of_days.
How to decide
- You know the vehicle's emission rate or fuel consumption, from OEM specs, telemetry or your own data: BASIC uses your figure directly.
- You have a rental car code: ACRISS takes
acriss_car_type, a SIPP code or a pseudo code. DEFRA also acceptsacriss_car_typeandsipp_car_type. - You know the make, model and model year: EEA and EPA take
manufacturer,modelandmodel_year, with valid values listed in each methodology's vehicle database. - You need to reproduce a published factor year or choose an energy scope: DEFRA takes
methodology_versionandenergy_scope. - You know the route or distance: send it.
number_of_daysis a coarse fallback.