In early 2023 Great Western Railway (GWR) in the UK announced the purchase of several assets from emission-free battery and hybrid trains manufacturer Vivarail, which entered administration in December 2022. The administration of Vivarail came as a shock to the UK rail sector, with many in the industry noting that it was a great loss to both the rail sector and to decarbonization in general.
GWR had been working with Vivarail on the development of its Fast Charge battery train technology and following news of the administration, the firm was keen to “take this forward,” says GWR senior program manager, Sonya Johns. “When the opportunity arose to purchase the Vivarail assets, it seemed like a sensible way to continue the trial,” she added.
GWR bought the intellectual property, rolling stock and equipment relating to the development of high-performance battery and Fast Charge technology designed to support the wider introduction of battery-powered trains on the UK’s rail network. The deal secured the future of planned trials of the technology in a real-world environment, which GWR, alongside Network Rail, was supporting between West Ealing and Greenford.
“When GWR took over the project it was at testing and commissioning stage,” explains Johns. “However, following the purchase there was a four-month period to re-mobilize, which included engaging the key supply chain, moving the assets and acquiring some of the Vivarail staff before the project could resume.”
The Fast Charge system consists of three key components: retractable charging shoe gear, which is mounted to the underframe of the train; short (4m) charging rails mounted between the underframe of the train; and the Fast Charge Battery Bank (FCBB) installed beside the track, acting as an energy buffer between the train and the grid.
“While the train is stationary the shoe gear is connected to the charging rails and the traction batteries in the train are charged at full power from the FCBB,” explains Johns. “When the train has left, the FCBB is then slowly replenished at a much lower power from the district network operator (DNO) connection. The aim of the system is to recharge the train within existing dwell times without imposing impractical power demands on the local grid.”
The Fast Charge system has several benefits, according to Johns, including high charging power, enabling the train to be recharged in around 10 minutes; a standard DNO connection, avoiding costly power supply upgrades; full automation, with no driver interaction required; low safety risk (the charging rails are never live unless fully covered by the train); and minimal disruption during installation, as the FCBB is manufactured offsite and the charging rails are attached to existing sleepers.
“Furthermore, the shoe gear has been designed to be easily installed on any rolling stock, in the most friendly “secondary sprung” vibration environment – mounted on the underframe rather than on the bogies,” Johns comments. “The system is not specific to the Vivarail Class 230 battery train used in the trial and does not rely on any train-specific equipment. The system also supports the local grid and avoids peak power demands, enabling active grid balancing. And finally, it supports the use of renewables with intermittent supply. FCBB can charge when electricity is lower carbon,” she adds.
The one-year trial of the Fast Charge technology and the Class 230 battery train on the West Ealing and Greenford line will commence in spring 2024, following approval from Network Rail for use on the UK national network. GWR will capture and analyze data during the trial to understand how the technology performs in different conditions. “Testing and commissioning is progressing well, and no challenges have occurred yet!” concludes Johns.
The work, according to GWR, is part of its commitment to reduce the carbon emissions of its train fleet with a view to removing all diesel-only traction from the network by 2040, in line with the Government’s Transport Decarbonisation Plan.