Institute of Transportation, MOTC

Wei-Ying Wang, 2008.06
Institute of Traffic and Transportation National Chiao Tung University

　　The rapidly growing number of cars and motorcycles in Taiwan has inevitably brought a severe problem of energy consumption and air pollution. To achieve the goal of sustainability, it is imperative to propose strategies which can effectively reduce energy consumption and emissions of motor vehicles without a serious impact to ordinary economic activities. According to related reports, the engine size and age of vehicles have rather significant effects on gas mileage and emitted pollution, implying that economic development and environmental protection can be both achieved by simply encouraging people to choose fuel economy and low-polluting cars and motorcycles. Undoubtedly, it is important to develop the choice behavior models of type and vintage of cars and motorcycles, so that the corresponding strategies can then be proposed and analyzed.

 　　To this end, this study conducts a nationwide questionnaire survey by disseminating a total of 90,000 questionnaires, containing both reveal preference and stated preference items, to the owners of registered cars and motorcycles based on a stratified random sampling technique. A total of 2,379 and 2,536 valid questionnaires of cars and motorcycles are returned, respectively. Among these returned questionnaires, 1,419 and 1,249 questionnaires of the owners those who bought the vehicles in recent three years are selected for calibrating national car and motorcycle Logit models, respectively. In addition, to further scrutinize the differences of choice behaviors in various living environments, 23 counties/cities of Taiwan are first classified into three regions: major metropolitan, minor metropolitan and ordinary cities, then the regional car and motorcycle Logit models are developed.

 　　The calibrated results of the nationwide type and vintage choice models show that the fuel cost, purchasing price, insurance cost, maintenance cost of the vehicle and the income, gender and education of the principal driver are found to be significant. The calibrated results of the nationwide type choice model of alternative fuel vehicles also show a similar result that the variables of the fuel cost, purchasing price, maintenance cost, accessibility of refuel stations, purchasing subsidy of the vehicle and the income, gender and education of the principal driver are significant. Although most of these variables are also found significant at the regional models, however, they exhibit different degrees of effect on the choice behaviors, suggesting the necessity to develop regional models for the better description of local choice behaviors.

　　To demonstrate the applicability of the proposed models, the changes in the vehicle type and vintage market shares under various strategies, including increase of license tax and fuel fee, increase of fuel price, levy of registration tax etc., are examined. The results show that the market shares of large-size car (engine size larger than 1800 c.c.) and motorcycle (engine size larger than 125 c.c.) will decrease by 5.89% and 6.18%, respectively, if a registration tax of 50% vehicle price is imposed. 　　To increase 50% of usage cost of aged vehicles (more than 5 years for cars and more than 3 years for motorcycles), the market shares of aged car and motorcycle will then decrease by 5.33% and 6.64%, respectively. Moreover, to increase the accessibility of refuel stations is the most effective strategy for encouraging people to choose alternative fuel vehicles. Corresponding strategies are then proposed based on the applications.