Global menu

Our global pages


Hydrogen / battery powered freight trains: on track to help decarbonise rail transport?

  • United Kingdom
  • Transport - Rail


With governments around the world placing an increasing level of importance on the decarbonisation of their transportation systems (for instance, as reflected in the suggestions put forward by the UK House of Commons Transport Committee in its report entitled “Trains fit for the future” (the “Report”), which you can read about here)[1], it is becoming ever more important for the rail freight sector to explore and invest in renewable power solutions.

In that context, though, decarbonising rail freight transportation continues to prove a more challenging proposition than decarbonising passenger rail transportation. A significant reason for this disparity is the challenges associated with renewable energy sources’ ability to meet the higher energy demands of freight trains. Indeed, according to the Report, electrification is currently (and could remain) the only viable approach for decarbonised rail freight transportation[2].

However, there are currently several trials underway or under review with the common goal of advancing a viable use of hydrogen and/or battery technologies to power both long-distance freight and switcher (shunt) locomotives. These include:

  •  a[ES2]  trial of a hydrogen-battery powered freight train by Canadian Pacific (“CP”) as part of CP’s Hydrogen Locomotive Program (the “CP Program”)[3];
  • a collaboration between Ballard Power Systems and Sierra Northern Railway (“SNR”) to pilot hydrogen-powered switcher locomotives in California (the “SNR Pilot”)[4];
  • an agreement between Progress Rail and Pacific Harbor Line (“PHL”) regarding the supply of a battery-electric powered switcher train between Los Angeles and Long Beach, California (the “PHL Agreement”)[5]; and
  • a trial of a battery-electric hybrid freight locomotive carried out by Wabtec and BSNF Railway (“BNSF”) in California (the “BNSF Pilot”)[6].

Each trial is summarised and considered further below.

The CP Program

On 18 December 2020, CP announced a trial of an innovative hydrogen-battery powered freight locomotive. The trial is taking place across CP’s Canadian routes, which form part of its 21,000 km (13,000 mile) transcontinental freight rail network. CP’s network is normally served by high-powered diesel units with a total rated power of over 1,715 kW (2,300 horsepower) which travel long distances across Canada and the US. CP has opted to retrofit existing diesel freight trains with hydrogen fuel cells and battery technology, rather than developing a new concept train. Once in operation, CP will conduct rail service trials and qualification testing in order to evaluate the technology’s readiness for rail freight.

The SNR Pilot

Announced on 19 April 2021, the SNR Pilot sees the development of a zero-emission hydrogen-powered switcher locomotive, which is hoped will enter into service during 2023. In conjunction with this, a new hydrogen station is planned to be constructed by Royal Dutch Shell plc. It is anticipated that the SNR Pilot will pave the way for widespread deployment of the Ballard Power Systems / SNR-developed hydrogen-powered switcher across California, where over 260 switching locomotives currently operate. The majority of switcher trains in California use around 228,000 litres (50,000 gallons) of diesel fuel each year on average; Ballard estimates the adoption of zero-emission shunters could lead to a reduction of over 54.5 million litres (12 million gallons) of diesel per year.

The PHL Agreement

As part of this agreement, which was announced in November 2020, Progress Rail will supply PHL with a battery-electric switcher train for a demonstration project. The six-axle train will include battery capacity of 2.4 megawatt hours for a run time of up to a day, and will be capable of 3,200 horsepower. The train will provide on-dock rail services, including the movement of cargo, in the ports of Los Angeles and Long Beach, California. It is hoped that this switcher train will lay the foundations for further zero-emissions cargo movement at the port of Long Beach.

The BNSF Pilot

Running between January and March 2021, the BNSF Pilot involved the use of a battery-powered locomotive in conjunction with two diesel-powered locomotives to form a battery-electric hybrid consist, initially travelling between Barstow and Stockton, California. Should the pilot be deemed a success, BNSF will expand the trial to run on other routes and in different operating conditions located on its 52,000 km (32,500 mile) network across 28 US States and also in three Canadian provinces. The pilot uses novel technology that operates in a manner similar to how electric vehicles use regenerative braking, meaning that the total energy utilisation of the locomotive is optimised. Nevertheless, it is important to note that unlike the other “green” solutions mentioned above, the BNSF Pilot cannot be classed as zero-emissions, as (so far) the trial has involved the use of diesel locomotives to power the train in conjunction with the battery powered locomotive.


As is demonstrated above, it would appear that there is a strong appetite within the global rail freight industry to explore the potential viability of hydrogen and / or battery-powered locomotives.

The development of zero-emissions solutions that do not require electrification of rail networks is especially important in regions where electrification may not be an economically viable option, for instance in North America, where freight locomotives travel vast distances[7].

In other regions where electrification is a potentially more feasible approach to decarbonising the railways, the use of hydrogen / battery power has already been mooted as a complementary method to electrification in order to achieve the ambitious emissions targets set in many areas of the world (for example, the UK Government’s ambition to remove all diesel-only trains (including freight trains) from service by 2040, and its target to reach net-zero emissions by 2050). The fact that freight trains may be able to utilise and embrace these alternative power sources could play a role in supporting the achievement of these targets, and, ultimately, help to create a cleaner planet.

Finally, from a UK-perspective, it is noted that the Report concluded that the UK rail industry’s decarbonisation strategy should be flexible enough to incorporate viable alternatives to electrification that can provide the energy required by freight, such as hydrogen and battery-power, once these alternatives are demonstrably “clean, green and cost-effective[8]. The trials referred to above could help to make this speculation a reality.

How we can help

  • ES Rail Team: our global team of Rail specialists are experienced in the delivery of new rail projects and major enhancements. We have recently advised a Local Authority in respect of its procurement of battery powered trams.
  • ES Infrastructure Team: our global team has particular experience in advising on PPP and transport projects ranging from rail and roads to airports.
  • ES Hydrogen Hub: this one-stop shop provides legal insight into the key issues shaping developments along the entire hydrogen value-chain. 

[1] House of Commons Transport Committee, “Trains fit for the future?” Sixth Report of Session 2019-21:

[2]Ibid, Rolling programme of electrification, paragraph 34

[3]  “CP announces hydrogen-powered locomotive pilot project”: ; “Leclanché to Provide Advanced Battery Technology for Canadian Pacific’s Hydrogen-powered Locomotive Project”: ; “Hydrogen Trains: The Railroad Revolution of the 21st Century”: ; “CP announces hydrogen-powered line-haul locomotive pilot project”:

[4]“Hydrogen Trains: The Railroad Revolution of the 21st Century”: ; “Ballard to Power Sierra Northern Railway Switching Locomotive in California”:

[5]“Progress Rail and Pacific Harbor Line Sign Agreement”:

[6] “BNSF and Wabtec commence battery-electric locomotive pilot test in California”:

[7] For further consideration of why electrification of the rail freight network in the US may not be a viable means for reducing emissions, see:

[8] House of Commons Transport Committee, “Trains fit for the future?” Sixth Report of Session 2019-21, Conclusions and recommendations, paragraph 19