Calculating the carbon footprint of transport

Table showing the greenhouse gas emissions of a passenger travelling one kilometre in France, taking into account the impact of the vehicle’s use, manufacture and maintenance (gCO₂e/passenger/kilometre).

Comparison of the data, in ascending order:

• TGV (3 grams of CO₂e in total, of which 2.1 grams of CO₂e are from use; 0.6 grams of CO₂e from manufacture; 0.3 grams of CO₂e from maintenance)
• INTERCITÉS (6.1 grams of CO₂e in total, of which 4.8 grams of CO₂e is from operation; 0.3 grams of CO₂e from manufacture; 1 gram of CO₂e from maintenance)
• Coach (40.4 grams of CO₂e in total, of which 33 grams of CO₂e are from use; 4.4 grams of CO₂e from manufacture; 2.8 grams of CO₂e from maintenance)
• Car (69.2 grams of CO₂e in total, of which 38.6 grams of CO₂e are from use; 28.5 grams of CO₂e from manufacture; 2.2 grams of CO₂e from maintenance)
• Aircraft (125 grams of CO₂e in total, of which 123 grams of CO₂e are from use; 0.4 grams of CO₂e from manufacture; 2 grams of CO₂e from maintenance).

For car travel, the figure is based on a mix of electric and internal combustion engine cars. An average occupancy rate of 2.2 passengers is applied, corresponding to long-distance journeys.

For SNCF Voyageurs transport modes, 2025 figures are used for the usage, manufacturing and maintenance components (emissions related to maintenance include only the energy consumption used for the maintenance of our trains).

For other modes of transport, ADEME’s ‘Base Empreinte’ values are used for the usage and manufacturing components, and values from the Carbone 4 study for SNCF are used for the maintenance component.

A table showing the greenhouse gas emissions of a traveller travelling one kilometre in France, taking into account the impact of the vehicle’s use, manufacture and maintenance.

Comparison of the data, in ascending order:

• Transilien (11.5 grams of CO₂e in total, of which 5.7 grams of CO₂e is from use; 4.7 grams of CO₂e from manufacture; 1.1 grams of CO₂e from maintenance)
• TER (23.7 grams of CO₂e in total, of which 19 grams of CO₂e is from use; 3.1 grams of CO₂e from manufacture; 1.6 grams of CO₂e from maintenance)
• Coach (93 grams of CO₂e in total, of which 83 grams of CO₂e are from use; 7 grams of CO₂e from manufacture; 3 grams of CO₂e from maintenance).
• Electric car (97.4 grams of CO₂e in total, of which 12.4 grams of CO₂e are from use; 83.6 grams of CO₂e from manufacturing; 1.4 grams of CO₂e from maintenance)
• Internal combustion engine car (109.1 grams of CO₂e in total, of which 81.3 grams of CO₂e are from use; 25.6 grams of CO₂e from manufacturing; 2.2 grams of CO₂e from maintenance)

For SNCF Voyageurs transport modes, 2025 figures for the usage, manufacturing and maintenance components (emissions related to maintenance include only the energy consumption used for the maintenance of our trains).

For other modes of transport, figures from ADEME’s ‘Base Empreinte’ for the usage and manufacturing components, and figures from the Carbone 4 study for SNCF for the maintenance component.

For car journeys, an average occupancy rate of 1.6 passengers is applied, corresponding to the average distance travelled.

The data for coaches is calculated based on an average of the three types of coach (long-distance, inter-city and Île-de-France), weighted by the actual distances travelled.  

A table showing the greenhouse gas emissions of a traveller travelling one kilometre in France, taking into account the impact of the vehicle’s use, manufacture and maintenance.

Comparison of the data, in ascending order:

• TGV France (3 grams of CO₂e in total, of which 2.1 grams of CO₂e are from use; 0.6 grams of CO₂e from manufacture; 0.3 grams of CO₂e from maintenance)
• Lyria (3.4 grams of CO₂e in total, of which 2.5 grams of CO₂e is from operation; 0.6 grams of CO₂e from manufacture; 0.3 grams of CO₂e from maintenance)
• TGV Spain (6.5 grams of CO₂e in total, of which 5.5 grams of CO₂e are from use; 0.6 grams of CO₂e from manufacture; 0.3 grams of CO₂e from maintenance).
• INTERCITÉS (6.1 grams of CO₂e in total, of which 4.8 grams of CO₂e are from operation; 0.3 grams of CO₂e from manufacturing; 1 gram of CO₂e from maintenance)
• Eurostar Group (6.7 grams of CO₂e in total, of which 5.8 grams of CO₂e are attributable to operation; 0.6 grams of CO₂e to manufacturing; 0.3 grams of CO₂e to maintenance)
• DB & SNCF (15.4 grams of CO₂e in total, of which 14.5 grams of CO₂e are from use; 0.6 grams of CO₂e from manufacturing; 0.3 grams of CO₂e from maintenance)
• TGV Italy (10.1 grams of CO₂e in total, of which 9.2 grams of CO₂e are from use; 0.6 grams of CO₂e from manufacturing; 0.3 grams of CO₂e from maintenance)
• OUIGO Spain (11.1 grams of CO₂e in total, of which 10.7 grams of CO₂e are from operation; 0.4 grams of CO₂e from manufacturing; 0 grams of CO₂e from maintenance)
• Transilien (11.5 grams of CO₂e in total, of which 5.7 grams of CO₂e are from use; 4.7 grams of CO₂e from manufacture; 1.1 grams of CO₂e from maintenance)
• TER (23.7 grams of CO₂e in total, of which 19 grams of CO₂e are from use; 3.1 grams of CO₂e from manufacture; 1.6 grams of CO₂e from maintenance)

For SNCF Voyageurs transport modes, 2025 figures for the use, manufacture and maintenance components (emissions related to maintenance include only the energy consumption used for the maintenance of our trains).

This diagram explains how a passenger’s carbon footprint is calculated by train type.

At the top of the visual, pictograms show a passenger and various trains, with the following caption: a passenger’s GHG emissions by train type, expressed in grams of_CO₂e/km.

At the bottom of the visual, pictograms illustrate the formula used to arrive at the result shown above. This is the ratio of the consumption of electricity, diesel and biodiesel required for the journey in question, multiplied by the_CO₂e emission factor for electricity, diesel and biodiesel, and the number of passengers carried over the distance travelled.

It is this calculation that enables us to determine, each year, the average amount of_CO₂e emitted per passenger by mode of transport.