A rolling horizon approach for shunting operations : an emission oriented simulation study

Abstract

Marshalling yards are nodes in rail networks to sort railcars from incoming trains to outgoing trains. To built outgoing trains in the correct sequence, railcars are shunted by shunting locomotives. Thereby, green house gas emissions are emitted as those locomotives are usually diesel powered. As the planning of shunting operations is a very complex problem, heuristics, so-called sorting strategies, are applied in practice. In this paper the effects of practically relevant sorting strategies on green house gas emissions are studied in a rolling horizon model. The rolling horizon model is used in a simulation study to investigate the effects of sorting strategies and input parameters (like the number and composition of ingoing and outgoing trains) on green house gas emissions. The results indicate that for different parameter constellations, different emission-optimal sorting strategies exist. Thus, sorting strategy selection should be done carefully depending on the operational conditions at the shunting yards.