Operating at lower speeds and restricting throttle usage reduces the need for braking. A lower speed also has an allied benefit in reducing aerodynamic drag.
Train speed and throttle position is determined by grade severity, instructions from train control, interactions with other trains and loading and unloading activities. Opportunities may be limited by scheduling and service quality standards.
Most operators have conducted simulations to determine their ability to implement this opportunity which may require adjustment to train schedules and loading/unloading times. Once these are resolved, adoption can be immediate.
Fuel savings will vary according to grade severity and percentage speed reduction. Simulations indicate potential fuel savings of up to 8% for limiting throttle usage and up to 11% for speed reduction. However, increases in travel time may raise service issues.
Key implementation considerations
This opportunity entails no (or very little) capital cost. However, increased travel time may affect intermodal costs if trains need to leave earlier or arrive later. The risk of not meeting service quality expectations could result in reduced customer demand, which can obviously erode any advantage obtained and raise business uncertainty.
Examples of implementation
Union Pacific – Speed Reduction Initiatives fact sheet
This example of a fuel saving initiatives fact sheet (opens in a new window) PDF 252 KB produced by Union Pacific includes a discussion of their ‘Conservation Speed 50 program’. This resource provides examples of types of tasks that are not time critical where average speeds could be reduced (e.g. carrying empty wagons/containers) (Union Pacific 2011b).
For the full report on fuel saving opportunities in the road and rail sectors, see Fuel for Thought – Identifying potential energy efficiency opportunities in the Australian road and rail sectors (opens in a new window) PDF 1.5 MB.