Modelling of Sustainable Transportation System of a City: A System Dynamics Approach

Abstract: In this study, a system dynamics approach was employed to model the transportationdynamics of a city. This is to try and encapsulate the feedback relationships between thedifferent aspects of a transportation system. The system dynamics tool provides a usefulmethod for analysing the complexities of a sustainable dynamic system for the developmentof effective solutions. The research presented in this paper attempts to build such a dynamicsystem through a stock and flow diagram with VENSIM analysis that models the behaviourof a sustainable city. To analyse and acknowledge these interactions, this study use non-linearmodelling methods to see the behaviour of those systems. The results indicate that to be ableto develop and sustain a functioning transportation system with a high ratio of people usingpublic transport, called the public transport ratio (P.T.R.), there needs to be a high supply oftransport investment which is used as the control input to the system. However, the need forinvestment to meet desired P.T.R. is reduced when the population is reduced. Theenvironmental impact of transportation is taken into consideration in this system dynamicsmodel through CO2 emission. The CO2 emissions are greatly reduced when the populationgets reduced, as the ratio of people commuting with public transport is increased as well asthe total number of people is reduced. Furthermore, simulation examples are included tovalidate the study. The modelling approach suggested in this research might be helpful tofuture researchers so that they can modify and enhance such models for further analysis ofsustainable systems.