Hybrids On Track

Rolls-Royce made a splash with news about hybrid drives for rail applications at the InnoTrans, the trade show for railway and transport technology held in Berlin, Germany.

First came the announcement that Rolls-Royce signed a letter of intent to implement a new hybrid drive solution on Alstom’s Coradia Lint diesel trains with Alstom, the German rail operator Abellio, and Nahverkehrsservice Sachsen-Anhalt GmbH (NASA) that controls the regional rail passenger transport service for the German Federal State of Saxony-Anhalt.

The agreement includes the retrofit of Coradia Lint regional trains in the Abellio fleet with MTU hybrid drives (a brand of Rolls-Royce), starting with technical feasibility studies for the integration of hybrid drives developed by MTU into the rail vehicles and their use on routes of Dieselnetz Saxony-Anhalt, a diesel-powered rail network in Germany.

The four partners plan to sign a contract covering the retrofit of at least three vehicles once the studies have been successfully concluded and financing is secured. The conversion of the entire fleet of 54 Coradia Lint vehicles is under consideration.

The hybrid drives combine a modern diesel engine with an electric motor and batteries to recover braking energy, reducing fuel consumption and CO₂ emissions by up to 25%. In addition, the ability to run under battery power only can reduce noise pollution in city areas and stations by 75%, to 20 dB(A).

The Coradia Lint is a diesel multiple unit (DMU) that can reach operating speeds of up to 140 kph and is powered by two MTU PowerPacks, each based on the MTU Series 1800 engine complying with EU Stage 3b emissions directive. The Hybrid PowerPack is an even more environmentally friendly version of this proven drive system: it combines an MTU diesel engine plus an electric machine, which can be used either as an electric motor or generator, and the MTU EnergyPack battery system, which stores the energy recovered during braking. The total operating costs of rail vehicles with MTU hybrid drives are lower, since for example even brake pads and discs have reduced wear due to brake energy recuperation.

Over 2800 Coradia trains have been sold by Alstom to date, with 2300 of them currently operating in Denmark, France, Germany, Italy, Luxembourg, the Netherlands, Sweden and Canada.

“Our MTU Hybrid PowerPack is a pioneering high-tech drive system combining the benefits of battery and diesel-powered trains without the need for additional infrastructure. We look forward to working with our partners to bring this technology into regular service here in Germany,” said Lars Kräft, vice president Industrial Business at Rolls-Royce Power Systems, said.

More retrofits for MTU hybrid drives are announced with another letter of intent for Talent, Coradia Lint and Desiro railcars owned by the railway vehicles leasing company Alpha Trains Europa GmbH.

It looks like the entire Alpha Trains railcar fleet will be converted to hybrid drive systems following the successful completion of the design concept and the retrofitting of an initial Class 643 (Talent) DMU. Alpha Trains owns more than 140 rail vehicles, which are currently powered by conventional MTU PowerPacks.

Thomas Schmidt, managing director of Alpha Trains Europa GmbH, said: “With the hybrid drive from MTU, our intention is to further increase the attractiveness of our fleet of passenger trains for our customers and to make them fit for an even more cost-effective and environmentally-friendly operation.” The letter of intent is also sending a signal to local transport authorities that they should “consider the possibility of including alternative drive technologies, such as a hybrid retrofit, in tenders,” Schmidt added.

Alpha Trains and Rolls-Royce have agreed that initially a variety of hybrid drive solutions will be simulated and examined with regard to their suitability for use on specific routes. One possible solution is retrofitting with an MTU Hybrid PowerPack and an additional MTU drive system consisting of an electric motor and batteries. As soon as the optimum solution has been identified for Alpha Trains, the next step will be to retrofit a single vehicle, before moving on to retrofit the entire Class 643 fleet.

But the retrofitting of diesel cars into diesel-electric units is not limited to mainland Europe, as the trend has clearly crossed the Channel and Rolls-Royce closed two more agreements for the hybridization of railcars in the British Isles.

First, Iarnród Éireann Irish Rail – the state-owned railway of the Republic of Ireland – signed a Memorandum of Understanding for the supply of at least nine MTU Hybrid PowerPacks from 2021, with the plan to convert its entire Class 22000 fleet pending successful trials using up to 234 MTU Hybrid PowerPacks.

MTU has already demonstrated in simulations that its Hybrid PowerPack can, depending on route and timetable, produce fuel savings of up to 33% on the Irish rail network. Jim Meade, CEO of Iarnród Éireann Irish Rail, said: “We’re delighted to be able to join forces with Rolls-Royce in bringing a new and eco-friendly kind of rail drive technology to Ireland. Our passengers will greatly appreciate the ride on an even quieter train, and since this is a rail drive that spares resources, we all stand to gain from the benefits to the environment that it offers.”

The entire 22000 Class fleet of Iarnród Éireann Irish Rail is driven by MTU PowerPacks based on 6H 1800 R83 units. A contract was recently closed between Rolls-Royce and Iarnród Éireann Irish Rail for retrofitting newer, more efficient transmissions to three MTU PowerPacks. The same transmissions will be used in the new MTU Hybrid PowerPacks.

The second agreement involves Porterbrook, a UK-based owner of passenger rolling stock and it represents the first hybrid rail project in the UK with MTU Hybrid PowerPacks. Rolls-Royce will initially deliver two MTU hybrid units based on type 6H 1800 engines to Porterbrook. These will be fitted into a Turbostar DMU in the beginning of 2020 which will then be trialed for a period of six months during regular operations.

The agreement includes an option for the retrofitting of a second DMU with two MTU Hybrid PowerPacks. Based on the performance of the Hybrid fitted units, Porterbrook hopes to offer customers the opportunity to convert their existing Turbostar fleets into HybridFLEX trains.

Mary Grant, CEO of Porterbrook, said: “Porterbrook is committed to reducing the emissions and carbon footprint of our existing diesel-powered fleets. We hope our investment in this trial of MTU Hybrid PowerPacks will enable us to offer wider fleet fitment of this technology, so that our customers can reduce both emissions and operating costs, as well as improve air-quality along urban corridors.”

Warren East, CEO of Rolls-Royce said: “We are pleased to be helping to write a new chapter of environmentally friendly, quieter and more efficient rail travel in the UK. With the innovative MTU Hybrid PowerPacks, Rolls-Royce and our partner Porterbrook will be setting new standards on the UK network; helping to reduce emissions, increase fuel efficiency and improve the lives of people who live near train stations.”