Development of a new high-resolution traffic emissions and fuel consumption model

This paper discusses the ongoing development of a new high-resolution traffic emissions and fuel consumption model for Australia and New Zealand, as part of a modelling framework that contains other models for more aggregate scales (e.g. fleet composition model, average speed model). A high-resolution model is needed to adequately address increasingly complex policy questions. The development of such a model is facilitated by various developments in the international arena, for instance with respect to input and emissions test data. Some preliminary results are discussed, which show that the new modelling approach appears to produce satisfactory results in terms of model accuracy, reliability and robustness. It is believed that model performance can be further improved by exploring various options such as other statistical methods, modelling of individual vehicles instead of composite vehicles, use of (different combinations of) other prediction variables (e.g. other power functions, longer history effects), different response variables (other transformations, fuel-based indices), and so forth. It is also important to explore the performance of other model structures (e.g. simpler or more complex models) and further examine the interactions between availability and quality of input data, level of model detail and overall prediction accuracy.