International Transportation (67) 2 | 2015 38 How can trains operate more energy-efficiently? Energy efficiency, driverless freight trains, train control system Faced with rising energy costs, fleet owners are increasingly turning to the Leader driver advisory system (iCOM Assist) to improve the overall efficiency of rail vehicle operations. The system uses route, train and timetable data to calculate the best options to save energy, and provides the train driver with relevant recommendations. These can result in fuel savings of more than 10 %, as well as reduced wear and tear from in-train forces. Leading European freight operator DB Schenker Rail AG is currently installing Leader systems in 300 of its locomotives. Author: Dirk Seckler W ith decades of experience under his belt, the locomotive engineer is initially skeptical: His train still has several kilometers to climb before it will reach the top of the incline, but the driver advisory system installed in his cab for testing purposes has prompted him to reduce traction completely. He shakes his head doubtfully, but follows the system’s instructions. Under its own momentum the train glides effortlessly over the summit, and arrives on schedule without wasting fuel. This also avoids an unnecessary build-up of kinetic energy that would have merely been lost again during braking. Such scenarios are not unusual with Leader - even experienced drivers are surprised by the accuracy of the system’s recommendations. The learning curve continues: improvements even with-experienced drivers Scenes like this will soon be commonplace in countless locomotives belonging to DB Schenker Rail AG. After several months spent putting the advisory system through its paces on a variety of routes and under a range of demanding conditions, the logistics specialist was finally convinced that the system could help even highly experienced drivers reduce energy consumption on their trips- and the decision was made to install Leader in 300 of the company’s locomotives (figure 1). In more than six months of tests under real operating conditions, Leader has demonstrated that it can reduce total energy consumption and CO 2 emissions by 10 % or more. In-train forces are also cut by about 50 %, thereby reducing wear and tear, especially in long freight trains. Low average speeds also make efficient use of the buffer time built into every arrival schedule. And punctual train operations automatically increase track capacity. Figure 2: Leader driver advisory system - tablet Photo: Knorr-Bremse PRODUCTS & SOLUTIONS Driver Advisory System Figure 1: DB Schenker Rail AG is currently installing Leader systems in 300 of its locomotives Photo: Deutsche Bahn AG/ Jochen Schmidt International Transportation (67) 2 | 2015 39 Driver Advisory System PRODUCTS & SOLUTIONS Algorithm calculates maximum efficiency. At the heart of the system is an algorithm, familiar from Nasa’s Mars Exploration Rover Mission, combining information on speed, distance and time. The basic information is drawn from a database with parameters related to the train, track topography and timetable. A GPS receiver provides real-time information on location and speed (figure 2). Allowing for speed restrictions, waypoints and train dynamics, the algorithm calculates in real time the most energy-efficient drive strategy and supplies the driver with prompts via an in-cab display that uses clear symbols for maximally intuitive and user-friendly operation. The 300 Leader systems already in operation are still to some extent experimental: What information does the locomotive engineer require? When should it be provided? How much in advance should it be made available? And how is it best presented? Several versions of the manmachine interface are currently under evaluation. With 12 to 18 months, the average amortization period for Leader is relatively short, and rising energy prices are liable to shorten this even further. A back-office application with a range of analytical options is available, and a ‘plug and play’ function makes retrofitting easy. Since, in Europe, the system only uses the locomotive’s electrical supply and does not intervene in the control functions, no licensing is required. Deployment in the North American freight transport market The system was first launched in North America, where the railroad network, despite its length of 210,000 km, is regarded as one of the most profitable and cost-effective in the world and there is considerable interest in Leader on the part of freight operators. For good reason: The longer and heavier a train, the higher the benefit of the advisory system, because a heavy train consumes large amounts of fuel every time it moves off again after stopping. Such heavyhaul trains are found not only in North America and South Africa but also in northwestern Australia, where many mining companies operate their own fleet to transport minerals to deep-water ports on the coast. Driverless freight trains In Europe, the Leader application merely provides the locomotive engineer with prompts, whereas the system in North America already offers a degree of semiautomated operation comparable to the use of an autopilot on an airplane. However in cooperation with the Australian mining company Rio Tinto, Knorr-Bremse is now going one step further and trialing the world’s first fully automated heavy-haul freight train. Rio Tinto is implementing AutoHaul®, using a version of the Leader system developed by Knorr-Bremse’s North American subsidiary New York Air Brake (NYAB) as well as software from Ansaldo’s Automatic Train Operation and Automated Train Protection systems (figure 3). This application upgrades the functionality of Leader from a purely advisory role to a full-fledged train control system. The active communication links to the network and train control systems are already available in current versions using the core software, but up to now the data were merely passed on as recommendations or put into operation by a semi-automated control system. Now the train will operate completely automatically. For fully automated control, the technical requirements are much more stringent - as are the safety standards, which is why the entire software program is undergoing a complete revision in line with Cenelec standards. The underlying algorithm is identical for both freight and passenger operations, and in principle the basic functionality is also the same. But the details of configuration and prioritization differ and need to be individually programmed according to the specific operational scenario. Thus, for example, adherence to the timetable has higher priority for passenger operations than for freight. And the system only recommends that the train be allowed to coast if there is clearly an adequate time buffer. In terms of energy consumption and wear this makes more sense than maintaining speed and then braking upon entering the station. Leader systems are currently installed in some 5,000 trains worldwide and are also becoming increasingly popular for passenger operations, for example in Israel (figure-4). In the UK, Leader systems have recently been retrofitted to diesel multiple units operated by London Midland and Southern, members of the Go-Ahead Group. ■ Dirk Seckler Head of Sales for RailServices, Knorr-Bremse Systeme für Schienenfahrzeuge GmbH, Munich (DE) dirk.seckler@knorr-bremse.com Figure 3: Rio Tinto ore train Photo: Rio Tinto Figure 4: A comparison of operational data with and without Leader underlines the huge savings potential in passenger trains. Photo: Knorr-Bremse