Hybrid Modeling Approach of Car Uses in Germany on Basis of Empirical Data with Different Granularities

Abstract

The use of private cars in Germany has not yet been analyzed from a longitudinal perspective: most travel surveys consider only a single day. Daily car usage is not identical over a given period because car owners use their vehicles for daily routines (e.g., commuting) as well as for infrequent events, such as holiday trips. Another problem of short-period surveys is that they underestimate the share of cars used for long-distance travel. The current work may help to improve the reliability and realism of statements about the extent to which German cars could be replaced by electric vehicles. The authors developed a hybrid modeling approach that aims to obtain car mileage per day for a full year. This approach is based on empirical data with different granularities. Input data are derived from the annually conducted German Mobility Panel, including a survey of fuel consumption and odometer readings, and the long-distance travel survey INVERMO. The study showed that 13.1% of the modeled German private car fleet never exceeded 100 km/day during a full year. Furthermore, cars were driven more than 100 km on 13.3 days/year on average. Mainly used cars (first cars) of a household were used for longer distances rather than second cars. A comparison of average mobility figures from the model approach with the Mobility in Germany national travel survey showed the model results as reliable and realistic.

Electric Factor—A Comparison of Car Usage Profiles of Electric and Conventional Vehicles by a Probabilistic Approach

“…In our study, we use on one hand results of a car use model covering the period of one year based on survey data to observe a representative usage from CVs [8]. Based on hierarchical clustering and k-Means eight car usage profiles were defined on the basis of CVs in a previous study [9].…”

“…Car usage over one year based on NHTS data in Germany and California [8][9][10] was modelled by determining the (1) individual car travel data of survey participants during the week, (2) car usage for typical days of the year, (3) car usage per day during the period of the MOP survey, (4) car usage per day for the remaining days of the year. For a detailed description of the CUMILE algorithm, see [8,10]. For comparison of car usage between Germany and California, modelling concept for California is very similar to the original model in Germany.…”

Who Uses Freeways and Who Pays for Them?: Model-Based Analysis of Distribution Effects of Toll Tariff Systems in Germany

“…Therefore, this study developed the car usage model CUMILE (car usage model integrating long-distance events) further. CUMILE aimed to obtain the car usage per day for a full year (15). The outputs of the Germanywide travel demand model VALIDATE were used for the computation of the daily freeway mileages.…”

“…Therefore, in this study a heuristic assignment of cars to individuals was developed in the first step. This assignment enabled the derivation of a main user for each car in the household and an approximation of the mileage of each car for every day of the MOP week from the travel diaries of the car owners (15). The MOP participants stated for every survey day whether it was a typical day or a particular day (e.g., if the car was under repair or the car user was ill or on vacation).…”

“…A comparison of key car usage figures (e.g., the average daily mileage of the CUMILE with the 1-day MiD 2008 survey) showed that the model results could be regarded as reliable and realistic (15,19).…”