Energy Recovering in DC Railway Systems

For over a decade, Europe has focused on greening public transport, with modern railways playing a key role to reduce pollution and transport emissions because it is characterized by a relatively low ratio between energy consumption and transport capacity. However, DC railways waste a significant amount of the energy regenerated with dynamic braking. The adoption of an energy storage system can greatly improve this situation by increasing energy saving. This paper explores this issue starting from experimental data recorded during the monitoring of a railway traction unit in commercial service on different tracks. The energy flows during braking in real conditions has been analyzed, quantifying the amount of energy that can be recovered by adopting an energy storage system placed onboard trains or in railway stations.