Citylab.com 5 June 2019
In an effort modernize its rail system, the country is looking to a technology it pioneered in the 1930s and ‘40s.
Ireland’s quest to modernize its train network could soon make it a global leader in battery-powered trains.
National carrier Iarnród Éireann launched its request for proposals last week to purchase 600 new train carriages by 2040—a near-total overhaul of a fleet that currently contains 629 carriages nationally. All those new trains would run on electricity, and up to half could be powered by batteries. That would represent a remarkable transformation for a network that today runs largely on diesel.
An order of this size for battery-powered trains is unprecedented globally. It does, however, make sense when you understand the particular conditions Irish railways are working under.
By Northern Europe’s high standards, Ireland’s rail system is a little behind the times, and it wants to catch up fast. The only part powered fully by overhead electric cables is DART (Dublin Area Rapid Transit), the commuter rail system that serves the capital region. That in itself represents no small portion of the country’s rail traffic: DART contains nearly a quarter of the total Irish rail fleet (144 carriages out of 629 running nationally). Thanks to a €2 billion injection from the national government, this fully electrified network will be extended further out into the Irish capital’s hinterland—out as far as Drogheda, 30 miles to the north—with 300 new trains commissioned to serve the expanded network.
For the rest of the train network, however, overhead electric cables are probably a long way off, depending on the continuing goodwill and funding of future administrations. That’s where batteries come in: Up to 300 trains in the new order could be battery-powered, allowing them to reach almost every corner of the country without the need to install cabling everywhere.
Such trains are cable-battery hybrids that can run on both types of line. Where overhead cables are available, the train gains its power from them and charges its batteries. When the cables disappear, the train’s battery has enough life in it to power the train on conventional rails to the next cabled section. The batteries could also charge at train stations and gain some power from braking. This way, a little cabling can go a long way.
The solution seems sensible enough, but battery-powered trains are still a relatively rare form of transit. One possible reason for this is that the kind of country that goes big on new rail tech doesn’t necessarily need them, because most of their lines are electrified by cable already. Battery trains have so far been used more for smaller, less-frequented lines that have so far escaped electrification. They can be great for these, because they don’t require track alterations, but still deliver far greener, cleaner transit. Japan is already ahead of the curve here, having operated multiple battery-powered services since 2014, while the U.K. started some services in 2015. Austria also tested its first battery-powered model last month, while Scotland’s ScotRail has gone especially big by ordering 70 new battery-powered trains.
Ireland’s plan for up to 300 battery-powered trains still goes further than any other national rail system yet. As a relatively small country where distances are short, it’s perhaps better suited than most, as the lengths of track a train would have to cross before recharging via overhead cable wouldn’t necessarily stretch the batteries’ capacities.
And Ireland has a less-known history here: It was actually one of the world’s pioneers in battery-powered trains.
From 1932 to 1949, the country ran one of the earliest regular services of this type, running a service from Central Dublin to the nearby beach town of Bray that was powered by batteries invented by Irish chemist James J. Drumm. The technology was so novel at the time that the voiceover in the British newsreel footage below is obliged to explain what batteries are—“accumulators which [the train] carries”
As cars became more common and the dominance of oil-based fuels became increasingly unchallenged in the latter half of the 20th century, the service was switched to diesel, before ultimately closing for good. It did, however, function perfectly well for over 15 years, and may have even had an incidental role in making the purchase of contemporary battery-powered trains seem less unusual.
Ireland may not have a great reputation as a rail innovator, but in finding a relatively affordable way of reducing carbon emissions on an as-yet chronically under-electrified network, it could well offer other countries useful pointers.