Estimating energy savings from a train driving advice system

Abstract

TTG Energymiser is an in-cab system that provides real-time driving advice to train drivers with the aim of reducing energy use subject to meeting the train schedule. A survey of the efficacy of Energymiser has been undertaken, to provide evidence for marketing claims. Results from 23 different trials are analysed, where 16 of the trials were on passenger routes and 7 were on freight routes. Each trial consists of many trips, with Energymiser activated for around half, and yields an estimate of the change in energy use when Energymiser is used. A Bayesian hierarchical model is fitted to the 16 estimates from passenger routes and provides an estimate of the mean saving and the standard deviation of individual trials about the mean. The mean saving is 7.2% and the standard deviation of individual trials is estimated as 3.3%. The corresponding mean and standard deviation for freight routes are 8.4% and 5.8%, respectively.

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