Answers to questions.
What is the carbon footprint of the high-speed line?
The carbon footprint of the high-speed line project is positive 10 years after its commissioning.
Emissions of CO₂, a greenhouse gas that causes global warming, are mainly due to construction: 2.4 million tonnes of CO₂ equivalent for the new line, of which 34% is due to earthworks, 40% to civil engineering (related to concrete and steel consumption), 13% to rail equipment and 3% to other developments.
Once operational, the line will encourage modal shift to rail: with more journeys by rail, there will be fewer journeys by air and road. The complete South West high-speed line will then save almost 340,000 tonnes of CO₂ equivalent per year when it comes into service, and this will rise to 550,000 tonnes per year 20 years later.
Large-scale modal shift to rail
The Toulouse–Bordeaux–Dax high-speed line will help to avoid 4.3 million car journeys and 1 million flights. Thanks to this large-scale modal shift, the greenhouse gas emissions avoided will offset the consumption associated with the construction works. This offsetting means that the project will have a positive balance after 10 years.
For reference, the Bianco interim report on the high-speed line Sud Europe Atlantique (SEA – February 2019, available on the LISEA socio-economic monitoring centre website) shows that the CO₂ emissions generated by the construction of the Paris–Bordeaux line will be offset after 12 years thanks to modal shift. The project will be carbon-neutral by 2029.
Sustainable public transport
Depending on the source (e.g. the French Agency for Ecological Transition (ADEME) or the Ministry of Ecological Transition), trains emit 50 to 70 times less CO₂ than planes. A high-speed train that is 80% full is equivalent to 370 car journeys avoided.