TRASPOL REPORT 2/22: Between flygskam and tågskryt. A balanced travel policy for Polimi community

TRASPOL REPORT 2/22: Between flygskam and tågskryt. A balanced travel policy for Polimi community

The study aims at understanding the possible effect in terms of CO2 reduction of changes of modal shares applied to the real travels of Politecnico di Milano university.

We analysed the entire database of authorised travels of the Polimi community occurred in 2019, the year before the pandemic, consisting of nearly 18000 trips.

Modes used have been grouped according to our aims, in particular distinguishing between trips involving an air leg, trips using non-air public transport (train in particular), trips using only private transport. Each mode is associated to a unit emission factor in grams of CO2 per km.

Italy is the main destination of trips (11000 out of 18000). Germany is the second. Considering Italian regions, the nearest ones get most of trips. Lazio is however the region generating the largest amount of distances driven, due to the importance of Rome.

For short-range destinations, train is dominant for cities, while car is for sparse destinations, which is realistic considering the dispersion of industrial attractors typical of Northern Italy. The share of car drops beyond 200 km. Train is the main mode between 300 and 600 km, with shares around 70%. Above 600 km train share falls and begins the “reign of air”, but important exceptions exist such as Naples (800km, well served by HS train).

These figures are, however, quite different if we look at countries. Central Italy and Campania are the domain of train (82%) and plane is as low as 10%. In southern Italy and Sardinia, the proportions are reversed: 86% by plane, just 9% by train. The smaller neighboring countries are comparable in distance to central Italy, but the modal share is completely different: as low as 22% for Austria and around 60% for Slovenia and Switzerland. Trips to Germany and France are not homogeneous due to the size of the country but have a higher air transport (70-80%) that is comparable to Southern Italy and the contribution of train does not go beyond 20%.

Localisation of travels in the study area (dot size) and modal share of air transport (colour).

In designing flygskam policies to push travellers from air to train for “short distances” (typically below 600km), one must carefully consider the level of service of trains, which varies considerably. Milan is an interesting case, with relatively near cities just across the Alps (southern Germany, Lyon, Marseille, etc.) where train is not a viable option for many trips, while much farther destinations such as Naples that already are dominated by train. However, the contribution of air travels to these relatively near destinations is negligible with respect to intercontinental trips.

To test flygskam policies, we designed four scenarios and calculated the related CO2 savings if these trips passed from air to train.

  1. All trips below 500 km shift to rail;
  2. All trips below 800 km, excluding Sardinia, shift to rail;
  3. All trips below 800 km, excluding Sardinia, shift to rail if the trip is longer than 3 days;
  4. All trips by air towards destinations where train modal share is already higher than 50%.

To know the results of the simulations, download for free the full report:

Beria P. (2022). Between flygskam and tågskryt. A balanced travel policy for Polimi community. TRASPOL report 2/22. Milano (Italy).