The effect of energy and time efficient driving strategies on longitudinal heavy haul train dynamics

Railway operators are continually investigating ways to reduce the cost of heavy haul train haulage operations. Two main components that influence the cost of a haulage trip are energy/fuel usage and journey time. But other costs are more difficult to measure such as train and wagon wear, fatigue damage and derailment likelihood. Past research and train driving training resources recognise that generally energy efficient driving strategies provide the best train handling and therefore the lowest cost of train operation. However, more energy efficient strategies tend to be slower in order to reduce the amount of braking required. While slower journey times result in lower energy usage it has the disadvantage of reducing the capacity of the rail network and rolling stock utilisation and hence increases cost in this area. Evaluating the total cost of a train driving strategy involves many parameters. The paper presents a method used to determine the total cost of a number of train driving strategies used on an Australian heavy haul line. The results are used to show the various cost relationships between energy, time and longitudinal dynamics during typical heavy haul train operation. The paper also highlights ways cost analysis can be used to further reduce train operation costs.