Case study: Engineering for Traction Energy Reduction
Company - ScotRail
How was this solved?
The stabling of trains is a necessary part of operations, preventing excess movement of stock, holding them in position ready for service and in some locations providing time for light maintenance and cleaning.
In theory this is an ideal time to shut the train down leaving it dark and silent, however, in practice some lighting is needed when workers will be on board and in some cases the time between arriving in a sidings and leaving is not long enough to make a full power down realistic. At times like this a partial power down of non-essential electrical circuits is the best way to limit electricity consumption whilst leaving sufficient power for tasks to be carried out and leave the train ready for its next service.
New rolling stock now comes with a sleep mode programmed in to shut down all un-necessary electrical circuits after 30 minutes of inactivity. Older stock, however, is not fitted with this option which can lead to wasted energy consumption and complaints from lineside neighbours regarding light and noise emitted from a vehicle.
In these older vehicles the driver is the person who will leave the power on, or turn it off depending on the instructions received, making the decision remote from the issue. Automation simplifies the process reducing the amount of time the train is fully powered.
In 2015 ScotRail asked Alstom to investigate the possibility of retro installation of a sleep function on the class 334 fleet, which is fitted with a Train Management System (TMS). In response the system software was upgraded in the summer of 2016 to ensure all coach lights and heating is switched off automatically after 30 minutes of the driver’s key being removed.
To ensure the train remains safe whilst in sleep mode the emergency lights, compressor and frost protection heating remain on. A function to ‘wake’ the train from sleep mode was also designed in to give cleaners sufficient lighting to be able to work safely.
During the summer months the new sleep function hass led to a reduction in energy of 19% overnight and as the winter weather set in, and overnight temperatures drop to 0°, reductions of 49% in overnight energy use were experienced.
The project demonstrates that working with the manufacturer on vehicles with a TMS it is possible to reduce traction energy whilst still maintaining a safe operating environment for staff.
What were the outcomes?
19% energy consumption reduction in summer, 49% reduction in winter.
Asset / operations