As the shift to greener, more sustainable fuels accelerates, John Carrigan, US Business Development Director for Alternative Fuels, highlights the vital role hydrogen cylinders play.  

The transition to cleaner energy is gaining momentum across the United States, and the transportation sector – one of the largest emitters of greenhouse gases (28%) in the country – is a primary focus of this transformation. Three key technologies are leading the charge in decarbonising mobility: hydrogen, renewable liquid fuels, and electric batteries, each presenting unique opportunities and challenges.

While renewable diesel and biofuels have gained attention for their compatibility with existing diesel engines, offering a cost-effective way for fleet operators to lower emissions without significant changes to infrastructure, electric vehicles are dominating the zero-emission market for passenger cars and light-duty vehicles. On the other hand, thanks to the potential to drastically reduce greenhouse gas emissions and provide an energy-dense, long-lasting fuel source, hydrogen is showing great promise, particularly for rail and road transport. As the market continues to expand, we are seeing growing demand for Luxfer’s technology and expertise.

Advancing short-line railroads with hydrogen

Freight rail remains one of the most efficient modes of transport in terms of emissions per ton-mile, yet it still relies heavily on diesel engines. Short-line railroads, which serve as vital connectors between rural areas and the larger rail network, are no exception. While these systems have long been powered by diesel locomotives, the push for global decarbonisation is driving the search for greener alternatives.

There are a number of reasons why hydrogen presents an attractive alternative to diesel for short-line railroads. First, hydrogen-powered trains have the potential to match the energy demands of these lines while producing zero emissions, making them environmentally favourable. Second, the lower-density routes typically served by short-line railroads make them an ideal testing ground for hydrogen technology and infrastructure. The ability to retrofit diesel-electric locomotives with modular hydrogen fuel cell systems is particularly advantageous for smaller rail operators. By integrating hydrogen technology, they can reduce emissions without sacrificing the operational performance needed for freight movement. There’s also no need to purchase entirely new fleets – a critical consideration for operators with limited budgets.

Breakthroughs in engine technology

Innovation plays a critical role in scaling hydrogen adoption in the transportation sector. One of the most noteworthy developments is the introduction of the X15 engine by Cummins, a global leader in power solutions. It is a fuel-agnostic internal combustion engine that can run on multiple types of fuels, including hydrogen. This technology offers a more versatile and scalable approach to hydrogen adoption.

The X15 provides a practical solution to operators looking to make the transition from fossil fuels to hydrogen. By offering a platform that can run on diesel, natural gas, and hydrogen, it allows fleets and railroads to begin incorporating hydrogen into their fuel mix without committing to an entirely new set of equipment. This versatility minimises costs and helps operators adapt as hydrogen infrastructure continues to expand. Additionally, its fuel-agnostic design enables mixed fleets to operate with both hydrogen and conventional fuels, ensuring seamless operations during the transition period.

Optimising storage with hydrogen cylinders

One of the technical challenges for hydrogen-powered vehicles and trains is efficient storage. Hydrogen has a lower energy density per volume than traditional fossil fuels, necessitating high-pressure storage solutions to ensure enough fuel is available for long-range operations. Generally, hydrogen is stored in either Type 3 or Type 4 cylinders, each of which offers distinct advantages.

In the North American market, Luxfer offers two hydrogen cylinders: the G-Stor™ Go H2 cylinder with Type 4 technology and the G-Stor™ Pro Type 3 cylinder. The former, available in three sizes from 14.5 to 19.1kg, is a high-pressure cylinder that delivers good storage volumes whilst remaining lightweight and is capable of pressures up to 350 bar (5,000 PSI). The latter is a fantastic solution if fast fill is critical.

The Type 3’s Luxfer-manufactured aluminium liner, fully wrapped with aerospace-grade carbon fibre, ensure no wastage as it allows all of the hydrogen involved in the system to be utilised.

Traditionally, operators would choose a single type of cylinder based on the application. However, in the push for maximising space and fuel efficiency, there is a growing trend towards combining Type 3 and Type 4 cylinders. For example, a Type 4 cylinder may be used in a spot where weight savings are critical, with a Type 3 cylinder fitted in an area where space is more constrained, within the same train or vehicle. This hybrid approach allows operators to optimise the available space for hydrogen storage. Since Luxfer’s range is technology neutral, with each product addressing different client needs and applications, we are fully able to support this.

Looking at the regulatory landscape

While hydrogen is gaining traction in the US, regulatory gaps remain a significant obstacle. Unlike Europe, where governments are heavily investing in hydrogen infrastructure, the US lacks a cohesive federal strategy. Progress is being made at the state level, with certain states leading the way with policies that support hydrogen refuelling stations and hydrogen-powered vehicles, but there is no unified federal framework for hydrogen infrastructure and usage. This regulatory gap is a key challenge that must be addressed if hydrogen is to play a significant role in the future of the US transportation sector. The development of hydrogen-specific safety codes, standards for refuelling stations, and incentives for operators to adopt hydrogen technologies will be crucial for the sector’s growth.

Pioneering hydrogen storage in the US

Hydrogen is increasingly becoming a viable fuel alternative for transportation in the US. While challenges remain – the biggest of which is competing with liquids – its potential to reduce emissions and improve operational efficiencies makes the gas an attractive option for rail and road applications. Luxfer is proud to be at the forefront of this green energy revolution, helping to widen access to hydrogen. As a 125-year-old company with an 80-year legacy in gas containment, we have spent more than two decades developing hydrogen fuel solutions to power buses, trucks, trains, marine vessels, refuse vehicles and more.