January 15, 2018

Hydrogen: fuel of the future?

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A flurry of orders in late 2017 for rolling stock powered by alternative fuels are indicative of a trend that is set to continue in 2018. Kevin Smith looks at Alstom's contribution to this field.

ADVANCES in diesel fuels from the 1930s to 1960s ultimately spelt the end of the steam era for railways around the world. While the iconic locomotives have long been consigned to museums and heritage lines, as operators and transport authorities look to clean alternatives to diesel in the 21st century, steam could be about to make a comeback, albeit in a minor sense.

Steam along with condensed water are by-products of the process to convert hydrogen into electricity in the fuel cell installed in Alstom’s Coradia iLint train. The 140km/h two-car multiple unit was demonstrated to the press on November 10 at Alstom’s Salzgitter plant in northern Germany. The press trip was well timed given that the day before Alstom had signed an agreement with Lower Saxony Transport Authority (LNVG) for a fleet of 14 trains, which was a major breakthrough for the supplier and its alternative fuel platform.

Alstom CoradiaThe Coradia iLints will replace diesel trains on non-electrified routes in northwest Germany from Cuxhaven to Bremerhaven, Bremervörde, and Buxtehude, which are currently operated by Elbe-Weser Transport Company (EVB), from December 2021.

The contract includes 30 year’s maintenance as well as energy supply for the fleet with Alstom working with Linde, Germany, to install a dedicated hydrogen refuelling station at EVB’s depot in Bremervörde.

The €10m facility will be funded through a €8.4m grant from the German federal government’s National Innovation Programme for Hydrogen and Fuel Cell Technology. In the longer term this will be replaced by on-site hydrogen production using electrolysis, which will source electricity through a dedicated wind turbine. The hydrogen refuelling process takes less than 15 minutes, with up to 10 trains per day expected to use the refuelling station in 14-15 separate refuelling events during an 11-hour period.

The fuel cell, which produces the electric power for the train, and predominately traction power for acceleration, is the core of the Coradia iLint’s alternative fuel system. The cell, developed by Hydrogenics, Canada, is supplied by a combination of hydrogen and ambient oxygen, which is stored at 350bar in tanks fitted to the roof of the vehicle and provided by Hexagon xperion. There is sufficient H2 available for 1000km of operation. Electricity is sourced on demand with a smart energy and power system enabling the delivery of energy to specific systems as required, including to power the vehicle’s bogies, which are the same as on conventional Lint DMUs. Excess energy produced during this process is stored in lithium-ion batteries supplied by Akasol and is used as needed by the train, resulting in greater fuel efficiency. Excess heat is also used to warm vehicle interiors, with each carbody fitted with two HVAC units supplied by Spheros.

Alstom unveiled the train at InnoTrans 2016, and since then the manufacturer has tested the platform extensively. Initial trials in early 2017 at Salzgitter were conducted at 80km/h and aimed to confirm the stability of the vehicle and its braking power. It was subsequently transferred to the Velim test circuit in the Czech Republic where it was operated at its maximum speed of 140km/h. Two two-car trains have been manufactured so far and these are expected to begin line trials on the EVB network in spring 2018.

Opportunities

The €10m cost of the hydrogen station, while certainly more expensive than the equivalent diesel fuel, is significantly less than an equivalent electrification project. Indeed, Alstom is pitching the train at non-electrified routes where there is limited economic justification for electrification. In particular the manufacturer sees opportunities for the train across Europe, but especially in Germany, where there are currently 4140 DMU cars in operation. Alstom has already secured letters of intent from the state of North Rhine Westphalia to purchase 14 iLint trains for delivery in 2020-21; Hesse for the delivery of 20 trains up to the end of 2021; and Baden-Württemberg for 10 trains up to the end of 2021, with an option for five further sets.

In addition, with national governments committing to minimise emissions, Alstom sees significant opportunities for hydrogen applications in Britain where there are currently 3003 DMU cars in service; Denmark, where there are 1000; the Netherlands, where there are 351, and Norway where there are 95 cars. Critically, it is targeting new rolling stock tenders rather than projects to retrofit existing vehicles.

Alstom is also highlighting the train’s green credentials in its marketing of the platform. In particular, its capability to eliminate harmful NOx gases from the atmosphere which are produced from diesel engines, the levels of which are of increasing concern in cities around the world. The trains can also significantly reduce CO2 consumption - around half compared with the equivalent diesel engine when sourcing H2 from natural gas reformation, and around a tenth when sourcing H2 from electrolysis powered by clean electricity.

Mr Gian-Luca Erbacci, Alstom’s senior vice-president for Europe, told IRJ that financial support from the states of Lower Saxony, North Rhine-Westphalia, Baden-Württemberg, and Hesse in the development of the project was key to making this initial order financially viable. He also did not rule out similar funding arrangements in the future given governments’ desire to become more sustainable, particularly in light of their commitments to the Paris Accords.

“We will be looking for new tenders, and one’s that specifically state a preference for environmentally-friendly trains,” Erbacci says. “Under the COP23 agreement the demand to reduce CO2 is huge, and governments and authorities are looking for ways to reduce their carbon footprint. These applications give them the opportunity to do that.”

In addition, he says Alstom is open to working with different H2 suppliers, depending on the market and the circumstances of the order, and the company is by no means tied into a partnership with Linde for future projects.

This added flexibility should leave Alstom well-placed to supply the Coradia iLint in different markets in the near future. The supplier is certainly confident that it has the platform to capitalise on a growing desire for clean and green transport.

“The transition from steam to diesel took 20-30 years to complete, and with certain countries committing to zero emissions by 2030-2040, we believe we are at the start of a new transition: the migration to zero emissions trains,” says Mr Wolfram Schwab, Alstom’s vice-president for regional and inter-city trains.