GWR electrification
THE ability of Great Western Railway’s Class 800 bi-mode electric multiple units to meet current and future timetables is under scrutiny by the train operator, due to their maximum speed in diesel mode of 100mph.
Network Rail’s electrification of the Great Western Main Line is taking place on a discontinuous basis, and the trains will have to run on diesel power between energised sections at potentially lower maximum speeds than the current High Speed Trains, which can operate at up to 125mph.
However, uncertainty about exactly which sections will go live (and when) means that planning future timetables when the fleet begins entering service from next year is proving difficult. The Class 802s have a design speed of 125mph under electric traction.
Asked by RAIL whether the company had examined the possibility of uprating the Class 800s to operate at 125mph under diesel mode, like the Class 802s that are being built for GWR, a spokesman said: “Class 800 testing only began on the Great Western Main Line last month, and we’re not aware of any investigations into routinely running at these speeds.
“However, we continue to talk with the Department for Transport to investigate ways of delivering the full package of capacity and frequency improvements we promised in the new GWR franchise, despite the challenges of
electrification. The delay to Network Rail’s electrification programme has always meant that although some benefits can be delivered without complete electrification, the full benefit of the new trains would be limited until the infrastructure is completed.”
Hitachi also responded to the suggestion, saying: “Hitachi Rail and the Department for Transport are continuing with testing of the trains under diesel power in order to ensure that the passenger benefits of these new trains are delivered as soon as possible.
“This testing has been under way only for a matter of weeks, and there have been no investigations or conclusions drawn about diesel running. Train testing is ongoing and progressing well, and the outcome of this will in due course help to inform GWR’s timetabling decisions.”
However, industry insiders told RAIL that the 100mph diesel limit on the Class 800s “would have an impact”, although their faster acceleration compared with a High Speed Train may limit this, particularly on the western section of the Great Western Main Line from Swindon to Bristol and South Wales.
“The real challenge is that the granularity of dates is next to useless for timetable planning purposes,” a source told RAIL.