What is Škoda Transportation doing to help electrify the rail network?
The core business of the Škoda Transportation group is the development and production of different kinds of rolling stock. Our products range from tramcars to metro trains, different kinds of electric multiple units and locomotives. This portfolio is supported by our own subsidiaries developing vital train systems.
Skoda Electric, for example, provides state-of-the-art traction equipment, while Skoda Digital is responsible for modern train control and diagnostic systems, and Poll for ventilation and air conditioning units.
In addition, Skoda Electric is a well-known supplier of electric buses and trolleybuses. We are moving with the times, and the goal of our development is to find the best technical solutions taking into account customers’ requirements, legal regulations and state-of-the-art technology.
What new technological developments has Škoda Transportation made recently?
For years, Škoda Transportation has been supplying modern, efficient railway vehicles ready to operate on electrified networks for many customers. The relatively new customer requests for emission-free trains for non-electrified routes, often driven by regulatory requirements, lead to the development of trains based on battery or hydrogen technology.
Škoda Transportation is already working on such solutions and compared to other market players, we can fall back on our great know-how and experiences. In the bus segment alone, we have supplied over 14,000 trolleybuses and electric buses. We have also tested a prototype of a hydrogen bus equipped with a power cell.
Even if railway vehicles are in a different performance category than buses, we can use most of our knowledge to build up the battery power supply unit for trains. On board energy storage and supply units are a necessary but not sufficient precondition for network independent operation. As the supplied energy is limited by weight and available space, additional changes must be made to extend the operational range.
We are considering and optimizing all aspects that affect energy consumption. LED lighting, highly efficient heating and air conditioning systems, extremely efficient traction components, lightweight construction of the car body and interior are just a few examples of development areas.
What key projects is Škoda Transportation working on right now?
Meeting the requirements of our customers, Skoda started developing a battery electric multiple unit (BEMU) train based on the proven Regiopanter platform. This kind of train will have a dual-energy system, which means it will be powered by battery on a non-electrified network and by a pantograph when running under a catenary line. This solution is the most economical for routes running partly under overhead lines with a non-electrified section up to 80-100km. In such cases, no charging stations are necessary; the vehicle is charged as it runs only in the electrified part.
Are you running any pilot projects looking at new technologies?
We are currently working on a special battery solution, customized for the most demanding railway needs. Another important challenge we are facing besides battery technology is the issue of how to get all the additional equipment on board without reducing passenger capacity or comfort and conversely – to improve those parameters.
How is battery technology and charging infrastructure improving to make it better suited to railways?
Railway applications always pose a special challenge for technology. The systems must fulfill not only strong climatic, fire safety and mechanical requirements, but they also face limitations on maximum allowed weight, axle load and track gauge. These restrictions place very demanding requirements on weight and volume per stored energy unit. Also, the charging characteristic of the battery and connected infrastructure must be capable to transfer the energy necessary for the next route within minutes.
When the automotive industry, which drives the battery and charging technology development, was facing the same problems, huge research and development capacities were mobilized. They finally received batteries with improved properties, which can also be used in our branch. Research is still ongoing, and we can expect a new battery generation with improved capacity and better fire safety with the same weight and volume every few years.
I understand one of the key parameters for success in the tender for Estonian Railways was low electricity consumption – can you explain more?
The EMU for Estonian Railways is the latest member of the Regiopanter family. All previous experiences and service-proven solutions are implemented in this unit. Energy saving measures could be roughly divided into two classes: movement and comfort.
In the movement class, I would mention low unit weight, optimized aerodynamics, low rolling resistance and, probably the most important point, highly efficient traction components with super caps for the storage of braking energy.
In terms of comfort, I would emphasize the efficient HVAC system and thermal insulation. Some of them are contrary, and in these cases, it was crucial to find the optimal option based on experience and calculations. All these single steps contributed to decreasing energy consumption, but the sum of all implemented items led to the success.
What other developments have been made recently to make Skoda trains more energy efficient?
For us, the main contributors soon would be weight reduction through intelligent design and usage of new materials and technologies. We will also be looking at lowering air resistance, the use of permanent magnet motors, or HVAC systems based on heat pumps. An additional category is an intelligent assistance system supporting the driver in an energy efficient driving style.
What are the greatest challenges that the electrification of the world’s train network faces?
The electrification of infrastructure by overhead lines and supply stations is capital intensive and would only be economically reasonable for main lines. Environmentally friendly trains with on-board energy storage can replace today’s diesel trains at an alternative to the electrification of other lines.
Today, we can choose from two technologies: battery or hydrogen. Each of these technologies has its strengths in different applications. Therefore, I am expecting both of these technologies to coexist in the next ten years.
The application areas will be defined by maximum distance per charging/fueling in comparison to train and infrastructure cost. Due to recently used battery capacities, battery powered trains often need special charging stations at the end points of routes. Hydrogen powered trains usually only need fueling stations at network hubs, reducing the number of expensive fueling stations. Nowadays, for non-electrified distances shorter then 100km, it seems that battery powered trains are the better option; for longer distances, there is no emission free alternative to expensive hydrogen available on the market.
Due to the high cost of hydrogen production, transport and storage, this forward-looking technology can currently only be economically reasonable with the support of governments or EU-funding. On the other hand, the hydrogen industry and the necessary infrastructure are developing very fast, which expert believe will lead to a significant drop in prices by 2030.