Comparative evaluation of power-based environmental emissions models

This paper presents findings from a comparative evaluation of two Australian power-based models of fuel consumption and environmental emissions using traffic simulation. The simulation approach provides a number of advantages for this type of work through detailed modelling of road geometry and grade, driver behaviour, vehicle performance and traffic parameters. The power-based models were interfaced to a microscopic traffic simulator and applied to each vehicle on the road network. Second-by-second fuel consumption and pollutant emissions were estimated on a section-by-section and network-wide basis. The simulation study examined a number of abstract vehicle types and gathered detailed information about their speed profiles, acceleration, deceleration, fuel consumption and pollutant emissions. The results showed that the fuel consumption outputs were similar but the emission estimates were substantially different for the two models. The paper also compared the outputs of the two models against various standard tests. The results showed that both models provided higher rates of pollutant emissions when compared with available standard test data. The paper concludes with some recommendations for further research to enhance the performance of the models