New Technology - Hydrogen Railways Show Growing Interest in Hydrogen Interest is growing across Europe and even further afield in the use of hydrogen to fuel railway technology. In the UK, the Birmingham Centre for Railway Research and Education (BCRRE) has been leading the way in the development of hydrogen-fuelled railway trains. This has included detailed concept design work and modelling, the development of scale demonstrators including the Hydrogen Hero 1/5 scale locomotive, and more recently in partnership with Porterbrook, the HydroFLEX train which has now been approved for mainline applications and is running on Network Rail infrastructure.
spokesperson for Alstom said, “As the only company with an independently powered emission-free train fully approved for passenger service (our Class 230 BEMU) we knew we could build on that technology and our current approvals to deliver such a train.”
How Do Hydrogen Trains Work?
Hydrogen “fuelled” vehicles typically use fuel cells which combine hydrogen from onboard storage tanks with oxygen from the atmosphere to create electricity with by-products of water vapour and heat. It is a chemical process that does not involve combustion and there are no carbon or other harmful emissions. Both the Coradia iLint and the Breeze are hydrogen hybrids that take primary power from the fuel cell that is supplemented by a battery when required. A hybrid drive optimises energy efficiency of the train, allowing for regenerative energy capture in the battery and mixing energy sources to power the train. These trains are designed to operate where no other energy source is available, they are not bi-mode, they are a like-for-like replacement for a DMU intended to offer equivalent or superior performance over ranges of at least 600 miles.
HydroFLEX, the UK’s first hydrogen-powered train, began mainline testing in Warwickshire in September 2020
BCRRE is also working with key partners to develop rail specific refuelling solutions which will enable future hydrogen trains to be refuelled rapidly in a depot environment. Hydrogen-fuelled vehicles are complimentary to rail electrification, and vehicles such as the “HydroFLEX” train retain their AC electrification equipment meaning that they can operate both on the electrified network and the non-electrified network. Currently, one of the leading builders of hydrogenfuelled trains is Alstom. Their Coradia iLint train is the only hydrogen fuelled train to have operated in passenger service covering over 180,000km in service in Germany and now operating in Austria. It has been successfully trialled in the Netherlands and around the German regions. 41 trains have been sold in two contracts that include 30 year maintenance support agreements with Alstom. In the UK, Alstom has been working with Eversholt Rail and, together they have developed the “Breeze”. This is a hydrogen train designed for the UK rail network is designed to replace regional DMUs (diesel multiple units) across the UK and discussions are ongoing with numerous operators and stakeholders to secure fleet deployments. A
The Coradia Breeze
Returning to the HydroFLEX, (p60) this has a new propulsion system which is integrated into the existing traction power electronics system. The new propulsion system combines a fuel cell and a traction battery to provide power into the train. The traction battery effectively sets the DC voltage on the DC bus, and the fuel cell is controlled as a current source, injecting current into the DC bus in response to the various states of the traction system and battery. The fuel cell can therefore be run in its most optimized state and minimize the quantity of hydrogen which is used. The Hydrogen is stored in high pressure lightweight tanks. The gas is stored at 350 Bar, and passes through a regulator before being delivered to Spring 2021
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