In co-operation with Hannover University, German DB AG developed a driving advice system called ESF (Energiesparende Fahrweise). The system gives coasting advices based on track and train data, timetable, position, time and operational situation. Continuous speed optimisation could also be given by ESF but is presently not active. An average saving potential over 5 % on German ICE has been confirmed by tests and calculations. A pilot on ICE 1 and 2 was realised in 2001. In the middle of 2002, ESF is planned to start in all ICEs. Exact structure data of the entire network is needed in a reliable and convenient digital version in order to successfully run the new electronic timetable method (Elektronischer Buchfahrplan und La (EBuLa)) which is also required for ESF.