Hydrogen Batteries Driving UK Railways Towards Net Zero Targets

Pragmatism and ambition will be key to tackling the pressing challenge posed by climate change. In its 2019 report ‘The UK’s Contribution to Stopping Global Warming’, the Committee on Climate Change recommended that the UK Government should progress its delivery of Net Zero with far greater urgency whilst also ensuring the fair distribution of costs[1]. Despite the UK Parliament’s decision to pass secondary legislation extending the UK’s commitment under the Climate Change Act 2008 to reduce 100% of carbon emissions by 2050, relative to 1990 levels, the Committee on Climate Change has stated that current policy  is ‘insufficient for even the existing targets’, which aimed for an 80% reduction. In light of falling costs, the demand for innovative, technology driven low-carbon solutions to the UK’s Net Zero challenge is growing. 

One sector in which the adoption of such technologies has the potential to make a positive impact is in rail transportation. Currently, the UK rail network is only 42% electrified, a level significantly below other European countries such as Switzerland (100% electrification), Belgium (85%), the Netherlands and Sweden (both 76%), Italy (71%) and Austria (70%)[2]. Whilst levels of carbon dioxide emissions per passenger per kilometers fell by 10.3% in 2019 compared to the previous year[3], UK passenger trains still consumed 469 million liters of diesel resulting in 2,465KTonnes of CO2e being produced[4].

In November 2017, the Secretary of State for Transport cancelled three rail electrification programs citing significant passenger disruption and up-front capital costs of infrastructure as reasons why the Government would pursue running bi-modal trains alongside partial electrification[5]. The Government has since been criticized by key stakeholders for the stop-start nature of railway electrification projects and urged to refocus on a longer-term plan to decarbonize rail by 2040[6]. Efficient and cost-effective solutions will be essential to reaching this target.

A collaboration between train leasing company, Porterbrook (a train leasing company owned by GIIA members Allianz, AIMCo, Edf Invest and Vantage), and the University of Birmingham Centre for Railway Research and Education (BCRRE) has led to the development of the UK’s first hydrogen train, which is also the world’s first bi-modal electric hydrogen train. The ‘HydroFLEX’ concept presents a sustainable means of powering existing rolling stock by installing a hydrogen powerpack that allows a train to run on conventional electrified routes, as well as independently using the hydrogen technology. The project involved retrofitting a Class 319 train with hydrogen fuel tanks, a fuel cell and battery pack to provide transmission whilst producing zero emissions.

Without the need to change driver controls, or the dependence on electric lines, the train can operate across different parts of the UK rail network, offering a level of flexibility that lengthens the life of assets and ensures sustainable transport can benefit all communities. Recently, the HydroFLEX project received a grant of £400,000 from the UK government funded InnovateUK ‘First of a Kind’ (FOAK) programme, enabling the Porterbrook and University of Birmingham team to develop the final production design and mainline testing of the train[7], which is set to take place on lines in the Cotswolds and Scotland.

Research conducted by the Offshore Wind Industry Council and Offshore Renewable Energy Catapult has demonstrated that the UK is strongly placed to undergo a large-scale conversion to hydrogen across a wide range of sectors, including transportation[8]. Green hydrogen presents short term cost competitiveness for deployment across rail transportation, offering high levels of customer comfort, easy and cheap levels of maintenance, as well as a cost-effective alternative to full electrification.

HydroFLEX has also shown that the development of new technologies can support businesses across the economy, with multiple private sector partners involved in the supply chain; Chrysalis Rail for installation, Denchi Group for traction batteries, Ballard Power Systems for the fuel cell, Luxfer for hydrogen storage tanks, DG8 design support, Derby Engineering Unit for panels and brackets, SNC Lavalin for design and hazard identifications, Aura for exterior livery design and dB Cargo Crewe for the recommissioning of the unit. Moreover, the UK’s budding green hydrogen industry is projected to contribute a total Gross Value Add (GVA) to the UK economy of more than £160bn by 2050, based on lowest estimates, and £320bn in a best-case scenario[9], demonstrating the important role of the private sector bringing technology and services to market to help solve fundamental public policy challenges such as the transition to Net Zero.

Such a transition by 2050 will require a firm effort from public and private sectors to support innovative, cost effective measures which have the potential to reduce the level of emissions across entire industries and geographies. The HydroFLEX concept offers an example of how an effective collaboration between the private sector, academic research and government funding can deliver innovation capable of significantly reducing the impact of UK rail transport on the environment and helping the UK to deliver the emissions free economy of the future.


[1] Committee on Climate Change: Net Zero – The UK’s contribution to stopping global warming

[2] Allianz pro Schiene: URL

[3] Office for Road and Rail: URL

[4] Office for Road and Rail: URL

[5] Department for Transport: URL

[6] Railway Business UK: URL

[7] University of Birmingham: URL

[8] ORE Catapult: URL

[9] ORE Catapult: URL

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