Battery power options for lower traffic railways
Electric traction is often one of the first options considered when trying to decarbonise rail traffic as electricity can potentially be produced from renewable energy sources. However, the cost of conventional electrification for lower traffic routes often inhibits their transition from diesel traction power. This challenge is faced by many national networks on how to decarbonise their less intensively used routes in a cost-effective way.
Several alternative technologies exist for decarbonising these routes including battery, hybrid and hydrogen power sources. In 2018 Ricardo produced a research report to explore the potential for introducing battery-powered trains on sections of national networks where low traffic intensity means full conventional electrification is not deemed financially feasible.
The study was commissioned by the northern Dutch provinces of Friesland and Groningen who have committed to implementing emission-free rail transport within their jurisdictions.
The conclusions of the study – conducted jointly with Arcadis, a design and engineering consultancy - determined that by enabling batteries to re-charge during standstill periods at turning points, and supported by an appropriate range extension solution, rail vehicles on the routes analysed could operate by battery power within just a few years. This could be achieved without the need for conventional full route electrification.
A viable low-carbon option
Earlier studies of the provinces by Ricardo had established that the costs of converting the existing diesel-powered routes to electric traction via conventional electrification would prove cost prohibitive.
Ricardo and Arcadis were commissioned to explore whether battery-powered trains would suit the region’s mix of short turnarounds and relatively long routes.
Martijn Wolf, sustainability consultant at Ricardo, was a member of the research team: “We examined a range of existing and developing rolling stock, battery and charging technologies, including the use of batteries on bus networks, to look at techniques that could be successfully transferred to the rail environment.”
The study focused on whether it was possible to fit trains with batteries that could be charged during standstill at turning points, so-called 'opportunity charging'. This would be bolstered by an appropriate range-extender solution to enable the vehicles to complete a fulfil a full timetable each day without carrying extra batteries.
The study proposed two viable range-extender options:
- Partial electrification: This would involve installing partial catenaries along stretches of longer routes so that the trains could charge during operation as well as during station stops.
- Hydrogen: Converting hydrogen in a fuel cell into electricity to charge the batteries and/or directly provide the vehicle with power.
The project team modelled a range of partial electrification scenarios, from 4km of overhead electrification (representing 1.5 % of the non-electrified network) rising to 10.5km (4%). The goal was to determine the best approach; one that would complement station-based recharging points.
The final scenario which included 10.5km of overhead electrification on the route offered sufficient capacity to operate a full timetable and showed that the number of station recharging facilities could be reduced to offset some of the cost of the electrified sections.
The study concluded that ‘zero-emission’ trains would be feasible in the region within seven to ten years, with both Friesland and Groningen provinces, together with the regional operator, Arriva, being provided with greater understanding of the costs and the modifications needed to transition to decarbonised rail transport.
New trains were ordered for this region which were a combination of electric, battery and biodiesel powered and Ricardo has been intstrumental in the testing and approval of these trains for use in the Netherlands. You can see more on these hybrid powered trains here
If you would like us to perform similar optioneering or feasibility studies for your routes or indeed other battery related projects then please get in touch