Spatial disaggregation in transport modelling -- Modelling Europe with more than 100,000 travel zones

European transport policy pursues several targets, such as reducing CO2 emissions and improving the efficiency of transport systems. In order to investigate the effectiveness as well as the welfare impacts of potential policy measures, transport models are applied in policy consulting. However, the travel zones used in recent transport models operating at European scale are often too large, mainly due to complexity and data availability. These models can provide only limited insights into regional traffic flows.

In this thesis, an innovative transport modelling approach called HIPAT is introduced. HIPAT is based on disaggregated and homogeneous travel zones, and thus facilitates the modelling of European traffic flows, including long-distance, regional and short-distance passenger trips with a single, consistent transport model. This enables European policy makers to assess also regional welfare impacts when prioritising, for instance, investments in the trans-European transport network. The quantum leap from 1,500 travel zones at NUTS-3 level to more than 100,000 at LAU-2 level, while simultaneously reducing the model runtime from several days to one hour, can be facilitated by solving the trip distribution problem very efficiently at different spatial levels. ... mehrIn comparison to recent European transport models, the consistency of the overall modelling approach was also improved, by integrating the trip distribution, the modal split and the network assignment models.

Within the last nine years most parts of this thesis were researched in the course of the author’s involvement as a transport modelling and data specialist in the two European research projects ETISplus and HIGH-TOOL. In a first step, a modelling database was established covering regional indicators at NUTS-3 level and harmonised mobility indicators from travel surveys at country level. In a second step, the currently applied four-step transport modelling approach was intensively revised and the IPAT passenger transport model was developed. Its methodology has successfully been validated in the course of publishing the IPAT model with the HIGH-TOOL policy assessment model that was awarded the German Mobility Prize in 2017. In a third step, the introduced modelling database was disaggregated from NUTS-3 to LAU-2 level for an important long-distance road transport corridor between Paris and Budapest (the ‘’Magistrale’’). The compilation of this database was a key precondition in order to realise a prototype implementation of the HIPAT approach. The model operates on about 33,000 travel zones and has a runtime of two minutes. It was intensively tested at NUTS-2, NUTS-3 and LAU-2 levels and the results clearly demonstrate the advantages of smaller travel zones.

Solely LAU-2 level enables the modelling of regional and short-distance traffic flows. Hence, the implemented HIPAT model provides, for the first time, a sound basis for the assessment of regional welfare impacts of European transport policies. In a next step, the scope of this model should be increased to cover the whole of Europe, thus encompassing more than 100,000 travel zones.