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Bombardier BEMU



Rail Stories

Clean. Quiet. Electric – moving with battery power

Batteries as an alternative power supply for the transportation industry

In a world of finite resources, population growth, energy uncertainty and public pressure, the calls for the implementation of alternative power sources are now louder than ever. As a global leader in mobility innovation, Bombardier Transportation is at the forefront of developing transportation solutions that meet operators’ immediate needs to reduce their system’s total cost of ownership while delivering eco-friendly, sustainable alternatives that replace diesel and reduce CO2 emissions over the long term.

Various forms of battery-powered mobility have been around for nearly a century, but until recently, battery-powered mobility has been limited by the massive size and number of batteries required to move large vehicles. Any battery strong enough to move a heavy vehicle like a train would be too large for the train to carry. Yet recent advances in lithium-ion fuel cell technology have turned the corner and taken the idea of battery-powered mobility off the drawing table and put it onto the tracks.

While certainly a novel idea, the practical advantages of battery-powered mobility are not to be overlooked, and there are already examples of how Bombardier is driving the development of alternative power sources for the mobility industry.

Battery-powered mobility for Nanjing Metro

One of our earliest alternative mobility projects was for the Chinese city of Nanjing in 2013. There, along with one of our Chinese joint ventures, we won a contract to deliver 15 catenary-free low-floor trams to this city of over 8 million people. A vital rail hub in eastern China for both high-speed passenger and freight rail, Nanjing chose a next generation tram propulsion for their new urban mobility offering. Based on our BOMBARDIER MITRAC traction batteries, Nanjing’s trams can operate without overhead cables on 90 percent of its lines, re-charging seamlessly during regular passenger operation.



Nanjing metro’s batteries re-charge during normal passenger service three different ways: via the pantograph while running, while idle at tram stops and dynamically during acceleration.

This represents the first time lithium-ion batteries were ever used for catenary-free tram operation. Today, the technology operates on two of the city’s lines, one of which, the Qilin line features steep inclines and an elevated route that passes over a major highway – further proving the potential to apply battery-powered, catenary-free tram operation to nearly any city.

Aside from proven performance, the Qilin line also demonstrates another added-advantage of battery mobility – a reduction in infrastructure investment. Installing complex electrical catenary systems is not only expensive but also difficult to maintain, at the same time, catenary-free operation offers city planners more flexibility. Service with battery-powered vehicles means mobility can easily be extended into historic city centres, or other areas like parks, where installing a complex catenary system is either unwanted or unrealistic.

«Battery powered trains are far quieter and cleaner than their diesel counterparts.»

This achievement in bridging technology represents a major leap forward in the search for seamless mobility. But what does battery-powered mobility mean for travelers and operators?

Battery-powered electrical multiple unit commuter train

The potential of battery-powered mobility isn’t limited to smaller vehicles like trams, real-world applications are already showing that battery power is also a practical alternative to larger diesel-operated commuter service. In 2016, we were awarded Research and Development funding from Germany’s Federal Ministry of Transport and the Nationale Organisation Wasserstoff (NOW) in support of our ongoing project to develop a battery-powered train. And at the 2018 InnoTrans Expo in Berlin, we presented our latest rail mobility innovation: a fully functional battery-powered electric multiple unit (BEMU) train. Not only does our BEMU represent the first completely operational battery-powered train to enter service in the last 60 years, it also means that our hugely successful BOMBARDIER TALENT train platform is now available in a battery version.

But what are the practical advantages of battery powered mobility?


Lowered carbon footprint

Bombardier BEMU

BEMUs are a cost-effective, flexible and reliable alternative to diesel power offering far greater operational flexibility, reduced energy costs and easier maintenance with a far lower TCO due in large part to the relative mechanical simplicity.

Foremost, battery-powered trains are far cleaner than their diesel counterparts. In Germany, it is estimated that the local use of emission-free battery electric multiple units will play a major role in the government’s plan to reduce CO2 emissions in the transport sector, by at least 40 percent by 2030. In fact, if the electricity is generated by renewable energy sources such as hydro-, wind- or solar-power, a battery powered train can operate 100 percent emission-free. Therefore battery-powered EMUs will help authorities meet environmental commitments while delivering a green mobility solution that is sustainable for generations to come.


Reduced total cost of ownership

Battery-powered trains are not just the right thing to do, they are also the smart thing to do. For operators, battery trains are more efficient and deliver a lower total cost of ownership (TCO) over the vehicle’s lifetime. A recent study by the Technical University of Dresden in Germany proved the TALENT 3 battery train is the most cost-effective and CO2-free alternative to diesel trains in terms of TCO over the entire 30-year service life for almost all use cases. Aside from bridging non-electrified track sections, battery-powered trains also reduce costs by eliminating the need for heavy investments into overhead electrification or additional fuel cell infrastructure, as they can reliably cover distances of up to 100 km between charging.

«Its estimated that a BEMU can save operators up to 50% in terms of total cost of ownership»

For operators, the news is even better. Against the backdrop of growing competition, rising energy costs and fluctuating capacity utilization, BEMUs are a cost-effective, flexible and reliable alternative to diesel power offering far greater operational flexibility, reduced energy costs and easier maintenance.

Energy efficiency, especially over the long-term, is another clear advantage of a battery train. It is estimated that a BEMU can save operators up to 50 percent in terms of TCO. The new TALENT 3 BEMU can also regenerate braking energy and save it in the traction battery for the next acceleration cycle.

Building upon our success, our BEMU will continue with commissioning and type testing with the homologation targeted in 2019. One year of scale passenger operation will be carried out with the associated project partners, operator Deutsche Bahn, Regio Alb-Bodensee and Baden-Württemberg’s Land Transport Authority NVBW in Southern Germany. The Technical University of Berlin is also providing scientific and technical support for the project, including an operational concept for the demonstrator train.

ZEFIRO Express

Our battery technology can also be applied to the ZEFIRO Express as an alternative to high-speed diesel trains. It offers the same emission-free mobility, low total cost of ownership, slim environmental footprint and a premium passenger experience as the TALENT BEMU does, except the ZEFIRO Express was specifically designed to meet the demands of intercity and high-speed service.

Easily winterized for operation in cold climates such as the Nordics, the ZEFIRO Express has fewer moving parts than diesel powered trains. Its battery engines reduce vibrations for a smoother ride in addition to emitting up to seven decibels less noise than a diesel counterpart, benefiting passengers and those living near tracks or stations.

Operating without transmissions or complex engines, like the TALENT version, the ZEFIRO Express’ straightforward propulsion makes maintenance less frequent and far less costly. In addition, its extremely low CO2 emissions and ability to run long distances on battery power means that operators can extend service as far as 100 kilometres.

In addition, battery power allows trains to be less dependent on existing rail infrastructure. This means that extending service to new areas requires less investments as it replaces the complex and expensive to install and maintain catenary systems required for electric operation. In contrast, the ZEFIRO Express can easily cover the many kilometres of non-electrified gaps and provide easier, more frequent connections between a city and its outlying areas by running solely on its stored energy.

Increased power

Increased peak power reduces travel times

Lower emissions

Less CO2 and NO2 emissions with battery operation on non-electrified lines 

Reduced costs

Long-term total cost of a BEMU is significantly less than a conventional diesel train

Featured video

Bombardier’s bridging battery solution for electric trains provides maximum operational flexibility. With battery power, non-electrified sections of the track are easily bridged with quiet and clean 100 % electric trains, removing the need for high-emission diesel engines. This allows for more uninterrupted rail connections, reducing travel times and improving service.