Despite the findings of the Transport Select Committee’s (TSC) report ‘Rail Investment Pipelines: Ending Boom and Bust’, the Government does not accept that rail investment has systemic “boom and bust” cycles. The TSC considers that, (in England) electrification is a particularly acute case of this phenomenon and that laying off skilled teams due to the “pause” of the Midland Main Line will inflate the cost of later schemes. In contrast, it found that the Scottish rolling electrification programme delivers better value and stability.
In response, the Government agrees that “…electrification remains a key tool for rail decarbonisation,” and that the objective is decarbonising rail traction in the most cost-effective way. Such comments demonstrate a lack of engineering expertise. Only considering decarbonisation ignores how electric traction offers powerful, low-maintenance, lightweight traction with consequent cost, performance and capacity benefits. Unlike self-powered units, electric trains do not have the constraints of storing energy or onboard power units of a limited size. As a result, electric trains are the only practical form of high-powered net-zero traction.
Furthermore, the Government considers that, with improved battery technology, the optimal solution will vary by route despite this constraining future rolling stock cascades. Hence it does not consider a rolling electrification programme to be an effective way of achieving the decarbonisation objective.
Despite recent advances in battery technology, Battery Electric Multiple Units (BEMU) are not a universal solution. BEMUs are more expensive to purchase and operate and the discontinuous electrification they require has not-so-obvious costs of feeding isolated OLE sections and pantograph control. Furthermore, batteries cannot power freight trains and are not suitable for high-speed EMUs whose power requirement is proportional to the cube of their speed.
For these reasons, Transport Scotland and Scottish Rail Holdings consider that intercity lines with freight traffic should eventually be fully electrified. The BEMUs being procured by ScotRail are thus deemed to be a transitional solution. Furthermore, Scotland considers that a rolling electrification programme is essential for skills retention. For this reason, electrification is cheaper in Scotland.
In Ireland, Cork has ambitious plans for a fully electrified commuter railway which will not use BEMUs. This is partly because the voltage-controlled electrification technology developed by Network Rail has reduced the cost of electrification. Our feature explains the benefits of the city’s plan for a high performing electric railway.
Electrified freight trains benefit both freight and passenger traffic. On the West Coast Main Line (WCML), diesel hauled intermodal trains struggle to achieve 45mph up the gentle 1 in 335 gradient from Watford to Tring. Further north, such trains top the summits of the WCML’s northern fells at just over 20mph. Mixing such slow trains with fast passenger trains destroys capacity.
Sadly, it will be a long time before HS2 carries passengers as our feature on the project’s reset describes, but at last the project now seems to be under control.
With the cancellation of HS2 Phase 2a and no possibility of significant infrastructure enhancements on the congested WCML for many years, a medium-term capacity enhancement option could be increased electric freight traction. This could be done by, for example, electrifying the London Gateway branch and increasing power supplies. This would also support Great British Railway’s (GBR) legal duty to promote the use of rail freight.
The IMechE Railway Division’s technical tour saw some interesting light rail systems in France and learnt how the electrification of Cork’s railways was a part of the All-Ireland Rail Strategy which aims to double Ireland’s rail passenger traffic by large-scale electrification and other interventions. It is to be hoped that the forthcoming GBR long-term strategy will have a similar vision. We also report how the Railway Division’s Future of Rail competition was won by a young engineer who developed a phone app for freight train maintenance.
Our feature on the Railway Industry Association’s innovation conference describes the innovations on display and what is being done to promote innovation. The conference’s hackathon was won by 16-year-old Mikey Whiston whose article explains how his app considered the machine truth of rail ticketing.
This conference also showed various applications of Artificial Intelligence (AI) which the railway must embrace including the advanced Claude Mythos AI cyber model that can find system vulnerabilities, as we explain. However, as we show, AI has various issues. We also describe the launch of GBRX’s rail industry AI plan which explains why the industry needs the development of strategic capability to exploit the technology. Another GBRX document – ‘Pioneering a better railway for people’ – outlines its strategy to accelerate the adoption of new technologies.”
But it is wrong to focus only on innovation. GBR needs an informed engineering strategy, of which innovation is a part, to make best use of both emerging and existing technologies. For example, it needs to be recognised that on a mixed traffic railway the key capacity constraints are infrastructure configuration and different types of trains. Despite over-exaggerated claims for it, ETCS signalling offers little capacity benefit. In contrast, the use of electric freight locomotives, with twice the power of diesels, could significantly increase capacity.
An engineering strategy could also usefully address issues such as gauging, minimising wheel/rail wear, and adhesion. Malcolm Dobell’s feature on the Adhesion Research Group includes work to inform the business case for fleet fitment of equipment to mitigate low adhesion. His report on the work of the Vehicle/Track System Interface Committee notes that, after 200 years, the complex vehicle track interaction is still not fully understood.
An engineering strategy would also need to consider the future roll-out of ETCS and replacement of the soon to be obsolete GSM-R system. Clive Kessell reports on the slow progress of the East Coast Digital Programme (ECDP) and the need to reduce its cost. He also attended RIA’s Signal and Telecoms member interest group which covered various topics including the excessive cost of ECDP’s ETCS for which inappropriate assurance processes may be a factor.
To understand current systems, it is useful to look to the past. We have two such articles, one on railway telecoms since 1900 and another on the signalling of London Underground’s sub surface lines which is now being replaced by the Four Lines Modernisation (4LM) project.
Stabilising a WCML embankment with a deep-seated rotational failure at Harlesden without disrupting services was a particular challenge. We describe how this was done and how 440 digital twins of WCML earthworks are being used for monitoring and to predict failures.
As always, this issue of Rail Engineer includes some great railway engineering features. But an engineering strategy which recognises railway engineering and operational realities is needed if railway engineers are to maximise customer benefits in the most cost-effective manner.
Image credit: David Shirres