The country celebrated the 200th anniversary of rail transport in 2025, but the locomotives and carriages that ferry 1.7 billion passengers a year across the UK, alongside freight on wagons every day, wouldn’t look all that out of place to some of the rail network’s early luminaries. So what does the future hold for the UK’s rolling stock?
The UK rail market has stabilised after a “stagnant” pandemic era, reckons James O’Sullivan, product manager at train manufacturer Alstom, with ridership returning and rolling stock now “back on the agenda” as long-term growth prospects firm up.
More certainty about the future of rail travel after the slowdown caused passenger numbers to plummet means companies like Alstom can start to think about the future of rolling stock more clearly, assured that there is a future for the transport network.
O’Sullivan flags two big near-term design shifts for the UK market: level boarding to improve accessibility for passengers who otherwise would be locked out and new traction types aimed at the decarbonisation of diesel – changes he expects to reach market within a 2030s timeframe. That is important because carbon dioxide emissions are going in the wrong direction – up 4.5% year on year, according to official data.
Level boarding is an easier win, though not without its engineering challenges given Alstom has “never done a level boarding train for the UK market,” says O’Sullivan. But the key engineering challenge will be changing the fuel stock for trains in the years to come. “How far can we get with alternative technologies that would give us carbon-free travel?” he asks.
Some more outlandish ideas for the future of rolling stock fall more firmly in the realm of science fiction and don’t always help with the here and now, says O’Sullivan, who presents progress as mostly incremental and user-led. It can be tempting to think the rail network hasn’t moved on all that much in recent history, he explains, but that is not the case. Alstom and others are making headway on reliability, accessibility, cost and passenger experience, rather than “Can we put racing stripes on it, or can we put jet engines on it to go faster?” he says.
Even if the impetus was there for engineers to overhaul railways from scratch, pragmatism prevents that. Trains will still broadly look like trains in the future, says Paul Allen, director of the Institute of Railway Research at the University of Huddersfield. The UK’s loading gauge limits size, and steel wheels on steel rails remain the most mechanically efficient way to get people around, while alternatives such as hyperloop and maglev don’t add up on practicality and cost – at least not yet.
“While it looks ancient having a big steel wheel set running on steel rails, it’s actually a very efficient mechanical system,” Allen says – and we haven’t yet found a better alternative.
But innovation is still going on, just in smaller ways passengers often don’t perceive. “Really, for the railway to be good, you don’t want people to talk about it,” says O’Sullivan. “Yes, we want to be celebrated, but for the vast majority of users, you want to be silently in the background.”
Allen agrees that progress is more likely to be under the radar of the average rail user. Rolling stock innovation is increasingly happening in “background” subsystems, he says, especially braking and traction control. That includes adaptive wheel slide protection improving adhesion management and early work using AI and machine learning to reduce wheel and rail damage.
The next wave of rolling stock is likely to be defined as much by what sits around it as what sits on it. “The rail industry’s challenge in certain areas is capacity, and how do you get capacity?” asks O’Sullivan. “Ultimately, the lines are fixed.”
The same issue means Allen believes some routes will never be fully wired for electricity. “What do we do about diesel trains where we don’t have electrified routes?” he asks, adding that this requires engineering solutions including hybridisation, batteries and hydrogen, and discontinuous electrification that can top up power in sections. “It’s much cheaper to put a third rail down” than installing overhead lines in every case.
This is the story of innovation in the country’s rolling stock – more evolution than revolution, keeping passengers getting from one place to another as quickly, safely and reliably as possible.
The Rolling Stock Lifecycle Conference will take place from 13 to 14 May 2026 at One Birdcage Walk, London. This two-day event brings together key stakeholders from across the rolling stock sector, including designers, manufacturers, operators, maintainers, infrastructure managers and policymakers. Find out more and book at imeche.org/events
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