Study title
ICARO: Increase of car occupancy through innovative measures and technical instruments
Ref study 6359
Study language German
Contributing institutions
  • Transport
  • Safety
  • Urban transport
  • Strategies for changing modal split
  • Car occupancy
Geographical space
Europa (mit Berichten über Amerika)
Leading Questions: How can car occupancy be increased? What experiences have been made with carpooling in Switzerland and elsewhere? How difficulte is it to run real life projects on carpooling? What are the results of carpooling projects? What are coherent recommendations on carpooling?
Objective : The overall aim of ICARO is to investigate the measures and instruments that can increase car occupancy. ICARO will focus on transport policy research and will deliver valuable and accessible recommendations and guidelines on how to increase car occupancy at both local and national levels. ICARO will carry out a combination of both research and demonstrations, concentrating on the latter.
The objectives of ICARO are:
(1) to identify best practices concerning technical instruments and organisational measures to increase private car occupancy;
(2) to identify and understand the institutional, legal and cultural framework necessary for increasing car occupancy. There may be considerable differences between countries with respect to the acceptance of measures and instruments;
(3) to carry out a number of real life demonstrations on techniques and measures that can increase private car occupancy. These demonstrations will involve a mix of innovative and technical measures. The demonstrations will be carried out in 4 European countries. The demonstrations will concentrate on simple and easy to implement schemes on the one hand and on HOV-lanes as a technical measure on the other hand. In addition there will be studies that will analyse through modelling (changes in) the use of HOV-lanes (Saloniki, Salzburg, Leeds, Madrid);
(4) to investigate substitute behaviour that might occur as an undesired effect of schemes for increasing the car occupancy;
(5) to set up a methodology for selecting the right measures and instruments;
(6) to disseminate the results to all interested parties.
The promotion of carpooling (in the UK) sometimes called ride-sharing or car-sharing) could be a way of increasing car occupancy rates that are currently very low. However, the conditions for a nationwide carpooling strategy are not favourable for Switzerland. The only opportunities the author can see is for the sharing of bus lanes by carpool vehicles, for rush hour management on motorways, and for travelling to and from major events.
These conclusions are based on the many case studies of the EU project ICARO which, with the exception of reserved lane schemes in Leeds and Madrid, have not been very encouraging. Trials were also carried out in Switzerland within the ICARO project, with limited success - promoting car-pools in conjunction with Park+Ride at the railway stations of Lyss and Yverdon, reserved parking spaces for the Bern administration authorities, and an attempt via the Internet to organise car sharing for travelling to a large techno party in Zürich.
Car-pooling could be successful on a large scale if general conditions (e.g. true-cost awareness, congestion on the roads, and damage to the environment) were to change significantly.
Methods (description)
Erhebung der bisherigen Erfahrungen und der Rahmenbedingungen in den verschienden Ländern
Durchführung von Pilotprojekten, statistische Auswertungen, internationaler Vergleich der verschienen Situationen, Berechnungen anhand von Computermodellen

Methods (instruments)
Replicated study No
Financed by

Mandating institution(s)
  • Eidg. Departement des Innern - EDI, Bundesamt für Bildung und Wissenschaft - BBW, Nationale Forschungsinstitutionen, Hallwylstrasse 4, Postfach 5675, 3003 Bern
  • Eidg. Departement für Umwelt, Verkehr, Energie und Kommunikation - UVEK, Bundesamt für Energie - BFE, Monbijoustrasse 74, Postfach , 3003 Bern
  • Eidg. Departement für Umwelt, Verkehr, Energie und Kommunikation - UVEK, Bundesamt für Strassen - ASTRA, Monbijoustrasse 40, 3003 Bern
  • Kanton Bern
Ethical approval No
Study type
Data availability
Source (Updates)
Date created 19.04.1999
Date modified 08.08.2001
Start - End date 01.01.1997 - 28.03.1999