Feargus O'Sullivan is a contributing writer to CityLab, covering Europe. His writing focuses on housing, gentrification and social change, infrastructure, urban policy, and national cultures. He has previously contributed to The Guardian, The Times, The Financial Times, and Next City, among other publications.
The U.K. is testing a cleaner, quieter electric rail line that doesn't require power lines.
This week, the U.K. has been quietly making transit history: it’s just brought the country’s only battery-powered passenger train into service. The train, fitted with lithium phosphate and hot sodium nickel salt batteries, is now undergoing a trial run shuttling passengers on a 12-mile stretch to the northeast of London. You can see a video of it below (spoiler: it looks like a regular train). If it works as it should, it will be able to make its journey without any connection to electrification.
The potential upsides to the wide availability of battery-powered passenger trains could be huge. Not only would trains run more smoothly and quietly, the cost of fitting them with batteries would be far lower than the expensive business of electrifying whole lines with overhead cables. A perfected version of this prototype could slash diesel use and replace it with something potentially much less polluting. What’s already a form of transport with low emissions could become one of the cleanest possible ways of getting from A to B.
The technology isn’t exactly new, of course. Types of battery-powered train have been around for over a century, used in places such as factory complexes where steam or sparks might have proven dangerous. What’s new is the scale of Network Rail’s project and its potential for use with paying passengers.
The current train still isn’t quite the shape of things to come. It’s a retrofitted version of Britain’s existing electric trains rather than an entirely new model. As such it still has a pantograph that can connect it to overhead cables. This will come in handy if the trial run meets problems, as the train will be able to raise this pantograph to restore power.
More importantly, the train’s current battery life is short—very short. It can run for only about one hour, before requiring two hours’ worth of recharging. Until more powerful batteries and/or a less power-thirsty train are devised, this technology won’t be taking over on long distances anytime soon.
Even as it stands, however, this battery-powered train could be a useful asset on some existing services. Take the 12-mile stretch on which the train is now being tested as an example. In a service day running from 7 a.m. to 10 p.m., a battery-powered train running slightly below the U.K.’s average rail speed of 65 miles per hour could comfortably make 14 round trips and still have time to recharge. So the application here suggests short, shuttle-type services, such as an airport express route.
The battery/pantograph hybrid could also help patch up the gaps between electrified lines. Britain has quite a few of these gaps, notably on small branch lines that run between the main rail routes across the country. While it wouldn’t work for a long journey, battery power could still tide electric trains over the short distances where no cable power is accessible.
In short, the possible uses are myriad and the various directions in which the technology could develop pretty exciting. While 12 miles of Southeastern England is a modest start, Network Rail’s principal engineer James Ambrose’s enthusiasm isn’t misplaced. “It’s a game-changer for the whole industry,” he says in the video above. “It will affect absolutely everybody’s lives."