The sparks effect: remembering how and why railway electrification works

Gareth Dennis
8 min readMay 22, 2019


Electrification in England and Wales has not been as quick or cost-effective as expected, resulting in scheme cancellations and a loss of appetite in government. GARETH DENNIS investigates why Scotland still has a taste for new wiring projects.

A version of this article also appeared in Issue 873 (27 February 2019) of RAIL magazine.

At the end of 2018, and without much ceremony, electric test trains started running to Dunblane and Alloa, passing under 300 kilometres of wiring held up by 2000 newly installed masts. Of the initial Edinburgh-Glasgow Improvement Programme scope, all but the electrification of the Shotts line has now been completed, representing the near-culmination of five years of hard work.

However, this is by no means the end of electrification in Scotland.

There may have been a few slip-ups along the way, but such is the success of the ScotRail Alliance’s rolling programme of electrification that the question for Transport Scotland (TS) isn’t “if” but “where next”. Stirling to Perth, East Kilbride to Barrhead, the Edinburgh South Suburban line and the Fife Circle are amongst the contenders.

But why has this widespread success not been replicated south of the border?

Britain’s railways face two fundamental challenges — a lack of political will and a massive skills shortage. Overcoming these is clearly vital for the delivery of successful infrastructure investments, but what are the necessary ingredients for this to happen?

“Devolution is part of the mix” says Alex Hynes, managing director of the ScotRail Alliance. “One of the Scottish Government’s objectives is to create a greener Scotland. Clearly, electrification enables the creation of a greener country hence the rolling programme.”

“We are on the cusp of transforming the railways across Scotland, and not just on those routes which are electrified. Because we’ve freed up diesel trains — of which there is a shortage — which we can reallocate them throughout the country.”

Political will derives from the decisions made by our elected officials, who generally make better choices when they are well-informed.

On being asked whether having a technically capable and regionally aware client in TS was a major contributor to the success of electrification in Scotland, Alex’s answer is simple: “Yes. In Scotland, you’ve got a client who funds Network Rail Scotland separately and has two franchises to manage. It is very focused. I think that has undoubtedly contributed to a more successful picture here.”

“If you look at the devolution agenda — localism, being close to the action, seeing what the railway does and the benefits that it creates — I would argue it’s a good model.” Alex continues, and the contrast between TS and the DfT becomes more stark: “TS view the railway as a system, so we’re still firmly in the camp of electrifying railways and buying electric trains.”

As Iain McFarlane (Network Rail’s delivery director for Stirling/Dunblane/Alloa electrificaion) rightly points out, electrification is transforming the railway by “increasing the number of seats, reducing journey times and cutting emissions…” And passengers really do notice the difference.

“Electric railways are good in terms of the travelling public’s perception — they want to travel by electric train” says Brian Sweeney, senior project engineer for Network Rail’s Scottish electrification team.

“Airdrie-Bathgate started off in 2010 with six-car sets; now you’re struggling to get a seat on some of these trains because of the growth. Similarly, Paisley Canal is standing-room only now whereas before electrification there was plenty of room.”

Alex Hynes is a keen advocate of the beneficial impacts of an electrified railway.

Alex Hynes agrees: “Last time I looked at the ScotRail numbers, Edinburgh to Glasgow was the fastest growing bit of the network. It isn’t surprising. Not only have we cut journey times — albeit a bit inconsistently without a full Hitachi service — but we’ve delivered shed-loads more seats.”

“The Edinburgh Festival is a massive challenge for us that we manage very closely each year. The amount of seats we delivered during the Festival compared to 2017 was up by more than 20%. Similarly, when I was at Northern and we replaced two-car diesel units with 25-year old four-car electrics, we were getting 14% volume growth.”

This isn’t a new phenomenon. British Rail were well aware of the rapid growth in passenger numbers that followed the introduction of electric trains, and whilst many cite the InterCity 125 as the saviour of Britain’s railways, others argue that it was the electrification of the West Coast mainline and other suburban routes that began to turn BR’s fortunes.

Despite this, the UK has never really had a strategic vision for electrification.

In RAIL860, I spoke about the benefits of delivering rolling upgrades as part of a long-term plan, and it is difficult to find a better example of this in action than in the wiring programme squirrelling its way around the Scottish Central Belt.

Alex recalls: “When I first arrived in the job, I spent a lot of time defending the company’s reputation around cost overruns on EGIP Key Output 1 (wires along the Falkirk High line connecting Edinburgh and Glasgow) but actually this was a minor blip in a long track record of delivery.”

“There is a vision. In 2016 Scotland published its route study which was a long-term strategic document about what the future could look like. We’re doing the development work and ultimately the Scottish Government will look to see what they want to buy.”

Brian Sweeney adds: “We did something a few years ago — Transport Scotland were looking at the full electrification of the network including Wick, Thurso, Kyle, everywhere — and set the expectations that actually, if you did go that far, you’d probably stop at Inverness.”

If you consider the steady but relentless growth of Scotland’s electrified network, the idea of wires in Inverness quickly becomes credible. In the last decade, Network Rail Scotland have delivered about 500 kilometres of electrification on routes across the Central Belt, increasing capacity and speeding up journeys by displacing slower diesel units.

According to Alex Hynes, it isn’t just good fortune. “There’s an appetite in the Scottish Government to spend more on Scotland’s railway providing we can demonstrate that it represents value for money. Things are very different here, and arguably more stable.”

“Electrification enables rolling stock changes and cascades, depot improvements and crew training and all these sorts of things so change is an opportunity but it’s also a risk. I would argue that having a lower volume of consistent activity is better than having peaks and troughs.”

Scotland has arguably had a rolling programme of electrification since the mid-2000s.

A rolling upgrade programme also has the benefit of being responsive to change, such as alterations to technology or legislation, without causing too much agony. Brian Sweeney explains:

“Paisley Canal was the last scheme we did with Mark 3 equipment before we then transitioned to the new Series 2 kit. Around the same time we had the challenges of the TSIs. On EGIP KO1 we were probably mid-way through construction by the time we actually had a handle on what the regulator was expecting to see to authorise an interoperable scheme.”

The delays to the electrification of the Falkirk High lines resulting from changes to electrical clearance requirements were hugely frustrating for passengers and the delivery team, but the nature of a rolling programme means that the lessons learned from both a management and a technical perspective were carried forwards onto the next job.

“Shotts has shown that if we can have a firm scope before we let a contract, we really can deliver. Network Rail IP Scotland now has a single electrification team, too, so we are more closely aligned in terms of programme management. Unlike before, we are one team.”

To grow a strong base of engineering talent, the supply chain needs a reliable flow of projects. With boom and bust comes frequent personnel changes, and this has often been a serious challenge for Network Rail projects south of the border.

Brian doesn’t see the same problems for Scottish electrification: “There is this core team that has rolled from one project to the next and there are always the same familiar faces. There is a deep knowledge in our team, if not by design then certainly by default.”

“If we rewind back to 2005, the first recent bit of electrification we did was the Larkhall branch, then the supply base moved onto West Coast Route Modernisation, then Airdrie-Bathgate, after that Paisley Canal and then Rutherglen to Coatbridge, so the programme really started ‘rolling’ with these schemes.”

“It’s the same if you get a team together to deliver anything. They start off, they get together, they build, and once they’ve done it a second and a third and a fourth time, they start to get really good at it.”

There is one last key element that everything else relies on, though.

Alex Hynes puts it crisply: “Delivery. You’re only as good as your last job. If we continue to deliver electrification projects in Scotland on-time and on-budget, the Scottish Government will be more predisposed to give us more electrification projects.”

A long-term plan enables a steady pipeline of work which enables quicker and more cost-effective enhancements, but if the engineering teams cannot deliver successfully it all falls down. The political will dissipates. The supply chain struggles to recruit the staff it needs.

Scotland’s rolling programme of electrification isn’t just a model for the good delivery of electrification; it is a good model for the continued enhancement of our railway network as a whole. If Transport Scotland are to be believed, the Isle of Skye’s the limit.



Gareth Dennis

Rail engineer and writer. Hosts #RailNatter. Lecturer at PWI/BCRRE. Co-founder of Campaign for Level Boarding. Chair of NEREF. He/him.