Will Railways Be On Board for the Future?

A look at the state of rail transport in Germany from a scientific perspective

Throughout his 24 years as head of the Chair of Rail Vehicles at TU Berlin’s Institute of Land and Sea Transport Systems, Professor Dr.-Ing. Markus Hecht has witnessed the highs and lows of German rail transport. In an interview, he explains the challenges facing this environmentally friendly form of transport in Germany.

Professor Hecht, complaining about the rail service has become something of a national pastime, and not only during the recent strikes. Make a case for this form of transport!

The railway is actually a miracle of spatial efficiency. Our rail system means that up to 80,000 people per hour can travel in both directions, and every five minutes a freight train with a capacity of 4,000 tons departs from somewhere in Germany. In the USA, engines sometimes pull up to 30,000 tons, although it has to be said that these trains are more than two kilometers long. Leaving aside the small number of electric cars, electrically powered trains are the only form of zero-emission transport we have. Their energy efficiency is also very high: Rolling friction is low, drag is low, as the carriages travel in the engine’s slipstream, and the recuperation process means that a lot of energy can be recovered when braking.

I heard that coaches are even more efficient. Is this true?

A study produced by the Federal Environmental Energy makes this claim. The problem is, however, that carbon dioxidegeneration is counted twice for railroads. Once in the statistics for the energy sector for the production of electricity in power stations and then again for the railroads themselves. If we apply the same method used for combustion engine vehicles, then carbon dioxide emissions would only be counted once for the power stations and rail transport itself would be completely CO2-free. 

How does rail use currently compare with roads?

The railway’s share is still shockingly low. In terms of passenger kilometers, rail has a current market share of eight percent. In freight transport, however, it accounts for 17 percent of ton-kilometers. Annually, rail and road in Germany are responsible for 180 million tons of CO2 equivalents. It is estimated that railways could reduce this by 40 million tons. Firstly, by transferring passenger transport from road to rail, for example by increasing the reliability of trains and using double-decker carriages to increase their capacity. Secondly, by increasing the energy efficiency of railways.

What can be done to further increase energy efficiency?

Expanding the rail network with electric overhead lines would make an important contribution. Few people realize that only 61 percent of line kilometers are electrified. Current planning means we will only achieve 64 percent by 2030. By contrast, the last coalition agreement envisaged overhead lines on 70 percent of the rail network by 2025.

Doesn’t this just refer to less important branch lines where diesel engines operate?

We should not be deceived by the fact that almost 100 percent of long-distance passenger traffic is actually electric. Overall, a good third of train kilometers traveled use diesel engines, mainly for freight and above all local services. Diesel engines are only one-third as efficient as their electric counterparts. In addition, they cannot use braking energy at all or only to a very limited extent, whereas electric engines can recover up to 90 percent of braking energy through recuperation. Diesel engines also often operate for much of their routes on tracks that are actually electrified, simply because reharnessing the engines would be too time-consuming.

Why do you think Deutsche Bahn is so far behind schedule in this regard?

This brings us to a fundamental structural problem that also gives rise to other difficulties. There is a lack of incentives to make the right decisions. Deutsche Bahn is a holding company. There is DB Fernverkehr (long-distance transport), DB Cargo (freight transport), DB Netz (infrastructure) and so on. Saving money improves the budgets of all these subsidiaries regardless of how much damage this causes to the overall system. This affects the electrification process as well, as DB Netz is responsible for maintaining the tracks even if the funding for expansion is actually provided by the federal or state governments. And the maintenance costs for electrified lines are even greater. DB Netz is contractually obliged to transfer about half a billion euros profit to the federal government each year. Of course, given these conditions, they want to avoid higher costs. Swiss railways by contrast are not permitted to make a profit. Incidentally, 100 percent of the lines in Switzerland are electrified.   

Switzerland is of course the ultimate railway country and its hydropower means that it has always had a lot of electricity at its disposal.

That’s true. But India will also be completely electrified by 2023. Admittedly, everything In Germany is fairly complicated. There are hearing procedures for local residents, sound barriers have to be erected in some cases, and tunnels and bridges have to be rebuilt. But DB Netz doesn’t want to give up control despite having little planning capacity itself. They need to have the courage to use the services of other companies for planning.

You said that the wrong incentives also impact elsewhere.

Let’s take the need to increase the number of passing lanes on single-track lines essential for the smooth running of rail traffic. Deutsche Bahn’s 2017 expansion program identified 70 locations where such passing lanes are required. So far, DB Netz has only constructed 12. The reasons for the delays are similar to those for electrification - the passing lanes are really needed for DB Fernverkehr and freight trains, so there is little incentive for DB Netz. We can also see structural failings in the details. Managers’ bonuses are reduced if trains are late. That may sound good but the result is that trains are often cancelled when problems occur. They simply disappear from the system and are not included in the delay statistics.

Let’s return to passenger numbers. What can the railways do to attract more passengers? Not only in Germany but also throughout Europe.

We should perhaps mention here that from 2009 until 2019, the total number of rail passengers increased by 40 percent. However, the figure for 2009 was low due to the economic crisis, and 2020 saw a collapse in numbers due to the coronavirus. Integrating the European rail system remains a Herculean task. It seems almost absurd that following the European harmonization of platform heights, we still have two heights: 76 centimeters for us - and 55 centimeters for all other countries!

Why is this important?

Boarding takes longer: ten minutes for a full passenger change on long-distance trains if boarding is via steps compared with three if boarding is level at the right height. Not to mention boarding for wheelchair users. This is why Switzerland already has carriages with two door heights on some trains. One door opens in Switzerland and the rest of Europe, the other in the special case of Germany. It is perfectly possible to align platform heights in Germany with the rest of Europe.

What else needs to happen to ensure that the railway system is on board for the future?

For European city connections, we need modern and well-timed night trains to be able to compete with air traffic. The timetables should generally be designed in such a way that trains arrive at the major hubs every hour on the hour as well as half hour as far as possible. Switzerland, for example, does this, even in international traffic, and this enables much better connections – and that means more satisfied passengers. Reducing the number of tracks, such as from 18 to 8 in Stuttgart21, is of course completely inimical for this system.

Which technical innovations could further benefit the railways?

We could have another interview like this one about battery and hydrogen powered trains. However, these would only become important if we fail to make progress with electrification. Digital automatic coupling for freight trains provides greater safety and saves time. Here in Germany, shunters still couple the trains together manually. And then, of course, there is the modernization of interlockings. We have more than 500 interlockings of different ages that also communicate poorly with each other. If there are communication problems, all signals immediately go red. I’m afraid I am going to have to mention the railway paradise that is Switzerland again. There, all data converges in just five interlockings - and they manage the entire country with a very high degree of reliability.

Interviewer: Wolfgang Richter

Chair of Rail Vehicles at TU Berlin

How can trains run with less noise? How can the efficiency of their maintenance planning be improved? How much energy can be saved by optimizing how they operate? And how quick are automated couplings? These are the issues addressed by the Chair of Rail Vehicles led by Professor Dr.-Ing. Markus Hecht. The chair’s researchers measure the roughness and profile of wheel and rail with high precision and simulate the propagation of sound in carriages and tracks. Algorithms use measurement data from sensors in the train to calculate when cracks in axles or faults in springs could occur and use this information to plan maintenance intervals. The team also investigates sensors that communicate with each other and send cumulative data to a web cloud, for example to closely monitor the temperature, humidity and internal pressure of tank cars on freight trains.

The group is currently cooperating with DB Cargo AG over a period of three years to set up a test field for the automation of brake tests. Brake tests check the functionality of the braking system. This is a fundamental and time-consuming step in train preparation, and its automation would contribute to increasing the performance and competitiveness of rail freight transport. The aim is to roll this out across Germany and later the whole of Europe, and the project will run until January 2024.

One of the most important innovation projects in freight transport is the introduction of the Digital Automatic Coupler. In addition to the fully automatic coupling of wagons, this enables freight cars to be supplied with power and data to be exchanged across the entire trainset. A large industrial consortium comprising the German, Austrian and Swiss railroads and several freight car operators are conducting the extensive trials necessary before Europe-wide introduction. The trials are running from 2020-2022 with the Chair of Rail Vehicles providing scientific support. The group welcomes students from all science and engineering disciplines, particularly if they also enjoy mechanics, physics, and design theory.