Managing demand on the railways
The UK government has announced plans to invest billions in rail infrastructure, but the short-term answer could be in better managing demand.
In US author Bill Bryson's 'Notes From a Small Island', a memoir of his travels around the UK during the 1970s and 80s, he recounts a number of episodes involving train journeys.
At the start of one of them he asks a fellow passenger, a man with a long and luxuriant beard, how long he's been waiting for the train to depart. 'Put it this way,' the man says, 'when I got on I was clean shaven.'
Bryson marvels at the man's wry humour and stoicism, but for a typical passenger or commuter these days the reality of getting from A to B on the UK's chronically overcrowded network is no joke. Services are often late or cancelled, and when they do turn up it's likely to be standing room only. Passengers regularly have to be bussed from one station to another because lines are closed for maintenance.
Against this backdrop comes the repeated cry from various quarters for more capacity. But these calls cloud a wider range of issues that go beyond simply building more infrastructure and rolling stock. Not all of them are wholly concerned with rail engineering or technology either, and there's much that can be done in the short term to exploit existing capacity – of which there is a considerable amount to spare – while looking at longer-term solutions.
As Trevor Birch, transport expert at PA Consulting, explains, 'it depends on how broadly you interpret 'technology and engineering'. There are a lot of solutions that will help address overcrowding, but much probably relies on technology or engineering in wider senses than many people think.
'You have to think about both sides of the equation: increasing the capacity of the rail system – as in building more or improving its availability – or managing demand for that capacity, by reducing the size or number of trips or changing the timing of trips to spread demand more evenly. It takes a long time to build infrastructure, but you can influence demand more quickly.
'When influencing demand, however, you need to think about wider societal influences,' he says. 'For example, you can encourage passengers to stagger their journeys and change their trip demands, to travel to work at different times of the day – spreading the 'shoulder' of peak demand, especially in the mornings – or stop making some trips altogether by working from home.
'Working from home has long been suggested as an alternative to travel, and often dismissed,' he concedes, 'but my personal view is that we are approaching a tipping point when constraints and enablers will make it a real influence on demand. For example, superfast broadband will make videoconferencing and file transfer much easier from home, and economic pressures mean employers are increasingly seeking to reduce office space and unnecessary travel.'
Birch agrees though that there will always be a core of people who will need to travel to a place of work every day – people in retail, industry or call centres for example – although even then, he says, more of them will start travelling at different times of the day as the UK continues to move towards a 24-hour society.
In a more transport-specific context, he says, one technology that will transform this demand management in the shorter term is smartcard ticketing, similar to the Oyster card system in London.
'Smartcard ticketing allows much greater flexibility to pay 'as you use'. It enables 'carnet'-type purchases that can offer bulk discounts for irregular travellers, making it a lot easier for those who travel, say, two days one week then three or four the next, to benefit from season ticket prices or to pay off-peak one day and discounted the next,' he explains.
The problem with current season tickets, he says, is that the marginal cost of travel is minimal once you have bought one, so people travel because they have already paid for them.
Birch says smartcard systems will also improve throughput of passengers into and out of stations, since there's no more queuing for tickets, and less demand for staff at ticket offices, freeing personnel up to be deployed in other roles to encourage off-peak use of the system.
Presenting people with better information on the best time to travel, the best route to follow and the best way to connect with other services is another great opportunity, Birch says. 'It could help ease overcrowding if more people knew, in real time, what the service was like before they left home or the office. We can do this now using mobile technology, but provision could be much better.
'These are what I'd call 'soft' influences on traffic patterns. In short then, I think there are two approaches here – exploiting existing capacity, which offers benefits in the short term, and expanding or enhancing the capacity, which is a long-term issue,' he says.
In the long term, cross-industry body the Technical Strategy Advisory Group (TSAG) wants to double the network's capacity over the next 30 years. Also, in November 2010, the government announced an £8bn investment in the railways. Some experts, however, believe the TSAG's target is too modest, and that the investment should be greeted with caution.
Rebeka Sellick, head of research at rail technology consultancy Interfleet Technology, says, 'I wonder if we should we be looking for more like five times the existing capacity, instead of the mere doubling in the existing vision?
'Rail fulfils only a small proportion of UK journeys each year: doubling rail usage to, say, 150 billion passenger kilometres will not make much difference in the overall demand for transport (at 800 billion passenger kilometres) but five times would make a real difference.
'Also, while the government's spending review is very welcome, in reality it is for things that already need doing, as in the current plan for defined projects such as Thameslink, Crossrail, electrification in north west England and the Thames Valley, revamping Birmingham New Street station – which is a notorious bottleneck – and lots more, including supplying new passenger carriages.'
Train operators bear some of the responsibility here as well, but the traditional franchising system has not been conducive to investment by them. That's now changing, however, as Sellick explains.
'Although the existing, prescriptive, typically seven-year rail franchises have not encouraged operators to invest to ease this problem – given that this timeline is more on the scale of a one-off project in the minds of these businesses – the announcement in December 2010 of new, 15-year franchises, the first of which will begin in 2012 on the West Coast Main Line, will allow operators to plan and invest on a more strategic basis. This could enable significant capacity growth,' he says.
While Sellick agrees that many extra rail journeys could be made now without any increase in available capacity, she says to address capacity significantly in the long term we need radical action like bigger 'holes' – tunnels, bridges and so on – and straighter tracks to accommodate longer vehicles with larger cross-sections.
'Bigger holes and straighter tracks would be progressed selectively, eating the elephant in small parts, so to speak, picking out areas of the network with the lowest conversion cost and highest predicted rail passenger demand,' she explains.
The aim here would be to allow the use of 23 metre long, off-the-shelf carriages and wagons – as in mainland Europe – instead of the current 20 metre stock. They would be more cost-effective, Sellick says, because they have greater capacities and would not have to be built specially for the UK network.
'The existing rail network needs to be developed alongside the new-high speed routes which are being planned to maximise overall capacity according to demand forecasts,' she says.
Building new lines is one thing of course, upgrading existing ones entirely another. As PA's Birch says, 'You can perform wonders on new rail lines when you are working with a clean sheet of paper, but it's going to take a huge amount of money to upgrade the existing infrastructure, so you have to look at solutions that make the most of the existing infrastructure or make it easier to upgrade.'
Two such solutions now starting to come in are modular signalling and the European Railway Traffic Management System (ERTMS).
'Modular signalling is a new approach to providing the safety layer of signalling, using standard modules, any type of power supply and datacomms technology,' explains Mark Glover, head of innovation at Invensys Rail, which is contracted to deliver modular signalling technology to Network Rail. 'It aims to eliminate cost and time in designing, installing and testing signalling systems.
For UK implementations, he says, 'We use the UDP/IP protocol over a standard Ethernet network or Network Rail's existing telecoms network, whichever is most convenient at a given location. Also, whereas traditional signalling systems in the UK use a clean 650V dc power supply, which requires considerable amounts of copper laid along the trackside, our technology operates at 24V dc, which means that any appropriate power supply can be used, and they don't need to be big.
'Modular signalling itself is not designed to enhance existing capacity, but it does improve the business case for upgrading a line using existing signalling systems – and offers flexibility in operation,' he says.
'At the moment it's being applied to secondary lines in the UK – there's currently a pilot installation on the Shrewsbury-Crewe line which is planned to come into service in 2012 – although it's suitable for all types of line.
'Secondary lines are where upgrading is needed the soonest though, because of an historical lack of investment and where, until now, there hasn't been the business case for upgrading these lines using traditional signalling systems,' Glover says. 'Modular signalling is a far cheaper and quicker way around this. Not only is assembly quicker and easier but maintenance is lower too – which has a positive impact on the overall capacity of the line.'
The company is also an ERTMS developer and, explaining how this works with modular signalling, Glover says, 'The two are designed as separate 'layers' in the rail network control hierarchy. The signalling system sits 'under' the ERTMS, and if all the trains on a line are ERTMS-equipped then you don't need signals. You can have signalling without ERTMS, but not ERTMS without an underlying signalling system – although many suppliers are looking at integrating the two.
Maintenance is also lower with ERTMS, because part of the technology is cab-based, reducing the need to close tracks to carry out lineside work. This helps improve the availability of the system, which in turn of course provides extra capacity.
The trouble with upgrades
'In a generic sense, I think it will get worse before it gets better, mainly because it takes so long to implement new solutions,' Birch says. 'For example, the Thameslink upgrade was originally named Thameslink 2000, and as of 2011 it's still not complete. It's difficult to upgrade any part of the rail system in isolation – providing longer trains to boost capacity can't be done without providing longer platforms and addressing consequent signalling issues. You have to take a system-wide view here.'
As regards comparisons with mainland Europe though, he says, 'We have a very different infrastructure in the UK, so simple comparisons are unfair. We run a very different service pattern in the UK, combining passenger and freight traffic on the same lines, often with high speed and low-speed services.
'On the continent, they have much more segregated rail lines – freight, commuter, high-speed and so on – that are designed and maintained for their specific use; they also have a far more integrated view of traffic. In the UK, by contrast, we have been very car-oriented and still have a 'silo' mentality about traffic modes, often considering road and rail in isolation.
'We need to plan using longer term horizons and work out how to implement solutions more quickly. It's all about making more of what we've got while waiting for more to be built.'
Cost-effective technology that's easy to implement is only one way forward, therefore, but there's no single or small group of technological or engineering solutions to this problem. We all use the railways, so perhaps it's time we all started doing our bit as well.
Smartcards: Just the ticket
Anyone who uses their chip and pin bank card to pay for shopping will know that smartcards are nothing new, but there is also a contactless version of the technology that’s been adopted for some types of credit card.
It’s this type that’s forming the basis for electronic ticketing systems on public transport around the UK, and elsewhere in the world, because of the speed and ease with which transactions can be completed.
In the UK, the first and largest contactless system is Transport for London’s Oyster card, which has been operating since 2003. The cards can hold a range of tickets – singles, seasons and so on – that are added to it before travel and which can be used across the various methods of transport in the Greater London area. The cards can be ‘recharged’ in a number of ways when necessary, at retail outlets, ticket machines or online for example.
The technology inside the card consists of an RFID loop and a chip – on the latest cards it’s a MIFARE DESFire CPU. Passengers touch the card on an electronic reader when entering and leaving the transport system to validate it or deduct funds. The card does not have to be removed from a wallet to do so.
The card readers provide the electromagnetic field that powers the card’s electronics through inductive coupling with the RFID loop, and read the ‘ticket’ information on the chip, checking whether to allow travel, calculate the fare payable and update the information on the card. All Oyster transactions are settled between card and reader, and the readers transmit the transactions in batches to the back-office system, which acts mainly as a record of completed transactions.
As other UK transport operators began to develop their own systems, however, it soon became clear that standards on interoperability were needed to enable passengers to use them nationwide, so the Integrated Transport Smartcard Organisation (ITSO) was set up to develop a specification and support the development of interoperable systems. It covers every component – cards, readers and back-office systems.
ITSO-compliant systems are now running in may parts of the UK, although some are still at the initial roll-out stage and are for concessionary travel only, for older or disabled people. While Oyster itself is not currently compatible with the ITSO spec, London councils began issuing dual ITSO-Oyster cards in 2009 under the London Council Freedom Pass concessionary travel scheme, and there are plans to migrate all Oyster readers to the ITSO specification.
Standard control platform
The European Railway Traffic Management System (ERTMS) is designed to replace and standardise the 20 or so national train control and command systems across Europe.
It has two major components – the European Train Control System (ETCS), an automatic train protection (ATP) system to replace existing national ATP systems; and GSM-R, a version of the cellphone system using frequencies reserved for the rail industry, to provide voice and data comms between track and train.
Three application ‘levels’ define different uses of ERTMS as a train control system. Level 1 is designed as an add-on or overlay to a conventional line already equipped with lineside signals and train detectors.
Communication between track and train is via dedicated balises – railway-specific electronic beacons, known here as Eurobalises – on the trackside next to the lineside signals at required intervals, and connected to the train control centre.
When the onboard ETCS equipment receives authority from the Eurobalises for the train to move, it automatically calculates the train’s maximum speed and the next braking point if needed, taking into account the train’s braking characteristics and the track description data. This information is displayed to the driver through a dedicated screen in the cabin. The speed of the train is continuously supervised by the ETCS onboard equipment.
ERTMS level 2 does not require lineside signals. The movement authority is communicated directly from a Radio Block Centre to the onboard unit using GSM-R. The balises are only used to transmit ‘fix messages’ such as location, gradient, speed limit and so on. A continuous stream of data informs the driver of line-specific data and signals status on the route ahead, allowing the train to reach its maximum or optimal speed while still maintaining a safe braking distance factor.
Level 3, still in its conceptual phase, allows for the introduction of a ‘moving block’ technology. Under levels 1 and 2, movement authorities are determined using ‘fixed blocks’ – sections of tracks between two fixed points that cannot be used by two trains at the same time. With level 3 though, accurate and continuous position data is supplied to the control centre directly by the train, rather than by track-based detection equipment. As the train continuously monitors its own position, there is no need for ‘fixed blocks’; rather, the train itself will be considered as a moving block.
Introducing level 3 will enable the train to monitor and report its own integrity, which will do away with the need for track detection circuitry such as axle counters and/or track circuits.
Deployment of ERTMS in the UK began on the Cambrian line in north Wales in 2009. The plan is to fit all passenger, freight and on-track vehicles with ERTMS by 2034, and for all infrastructure work across the network to be finished by 2044.
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