The challenge of transporting hydrogen

Posted: September 05, 2025

When it comes to the decarbonization of industry, there has been no shortage of hype around the universe’s smallest and most abundant element—hydrogen. Since hydrogen can combine with oxygen in fuel cells to generate electricity, emitting only water as a byproduct, its potential for clean energy production is clear.

Many industry players consider hydrogen to be the best bet—so far—for decarbonizing certain hard-to-abate industries and processes such as steel, cement, and chemical production. Hydrogen offers particular promise in heavy transportation, too, since using hydrogen energy on a ship or truck often proves considerably more efficient than carrying the weight of a large battery. Applications are already well underway in domains like shipping and trucking, while many governments have made major investments into the potential of hydrogen, with around 70 national hydrogen strategies and roadmaps currently in place.

Many of these strategies specify their plans to produce and/or consume what is known as “green” hydrogen, which means hydrogen produced via electrolysis using renewable energy sources. The vast majority of hydrogen used worldwide is currently made from natural gas (“grey”) or coal (“black” and “brown”) through emissions-intensive processes; when those carbon byproducts are captured, the hydrogen is then referred to as “blue.” Green hydrogen is relatively easier and cheaper to produce in certain regions, particularly those where renewable resources like solar and wind are in great abundance.

Yet the transportation of hydrogen is no simple matter. Hydrogen is gaseous at room temperature and has a low volumetric energy density, which means it takes up a lot of space compared to other fuels unless it undergoes expensive and energy-intensive processes of liquefaction or compression then gets specially stored. It also has a tendency—exacerbated at high pressures—to embrittle steel pipes. A range of different transportation approaches are currently in place or in development, with more innovation likely to come.

Why most hydrogen is currently transported by pipeline and truck

Today, the most established means of transporting hydrogen is by pipeline. After undergoing a process of compression, gaseous hydrogen gets passed through a network of pipelines that are either retrofitted from natural gas pipelines or constructed for hydrogen specifically.

There are currently some 5,000 kilometers of active hydrogen pipelines worldwide. The USA’s 2,500-plus kilometers of relatively short pipelines are concentrated around the Gulf Coast region, delivering hydrogen to ammonia plants and refineries. A number of major hydrogen pipeline projects are currently in development. China has begun construction on a 400-kilometer pipeline; the European Hydrogen Backbone initiative aims for 40,000 kilometers of hydrogen pipelines by 2040. Ambitious plans have also been proposed for undersea pipelines to the Iberian Peninsula and North Africa, though some experts have questioned the feasibility of this particular initiative.

Pipelines are considered the most efficient, cost-effective method of transporting hydrogen over distances of up to around 3,000 kilometers, particularly in places with considerable long-term demand. Yet pipeline transportation also has its drawbacks. Hydrogen is highly flammable. As the smallest molecule, it is at risk of leakage; it can also cause embrittlement of the pipeline’s materials. Repurposed natural gas pipelines require careful monitoring, while building entirely new hydrogen pipeline infrastructure can be pricey and complex.

Over short distances, or where demand is not necessarily expected to remain stable, hydrogen is moved in trucks—either as compressed gas in pressurized cylinders or as liquid in super-insulated cryogenic tanker trucks. To enable the latter, hydrogen must be liquified by cooling it to extremely low temperatures. For trucking over long distances, liquid hydrogen can prove more economical than gaseous hydrogen because liquid tanker trucks can carry a greater mass of hydrogen that gaseous tube trailers can; still, the liquefaction process is highly energy intensive. Gas and liquid hydrogen can also be transported on ships.

New innovations can help crack the hydrogen transportation challenge

On account of these challenges, researchers have been looking to develop alternative technologies for the transportation of hydrogen—especially over long distances. One particularly promising option is ammonia, a stable compound of hydrogen and nitrogen already widely used in agriculture and industry. As part of the ammonia compound, hydrogen can be transported via pipeline, ship, or truck. Upon arrival, the ammonia is heated (“cracked”) to release the hydrogen.

Ammonia has a higher energy density than gaseous hydrogen. It is far less flammable and can be moved at scale using pre-existing commercialized transportation and storage infrastructure. Ammonia also requires comparatively less energy to liquify or pressurize. A further advantage of ammonia is that it lacks the embrittlement effect of gaseous hydrogen—though it has been noted, too, that the repurposing of natural gas pipelines for ammonia rather than gaseous hydrogen may be even more expensive. Cracking and synthesizing ammonia are energy-intensive processes, too, and the toxicity of ammonia has raised some safety concerns.

Still, the ammonia-based approach has met some interest, particularly in the context of intercontinental transportation. A Fluor study commissioned by the Port of Rotterdam Authority found in 2023 that it would be feasible to convert ammonia into 1 million tons of hydrogen using a large-scale cracker at the port. Ammonia cracking projects are also underway in the UK, Belgium, and Germany.

Another approach being explored for long-range hydrogen transportation is that of Liquid Organic Hydrogen Carriers (LOHCs), organic molecules in which hydrogen has been covalently bonded and can be removed upon arrival. These carriers, in addition to being liquid under normal atmospheric conditions, avoid the toxicity concerns associated with ammonia. Last year, the German LOHC firm Hydrogenious were working with ACME Group to jointly explore the technology’s possible use in large-scale supply chains from production in Oman to supply hubs Europe.

Green hydrogen exporters face a unique set of challenges

According to the IEA, most hydrogen today is consumed near where it is produced but it is likely that growing demand means, “the production of low-emissions hydrogen in regions with abundant renewable energy resources will become more economically attractive, leading to an increase in transport needs to connect production sites with demand centers.”

Europe, for instance, announced in 2022 plans to import some 10 million tons of hydrogen by 2030: as RMI has reported, European decarbonization goals require the output of new renewables to go towards electricity, so green hydrogen imports can help reduce domestic demand for renewables in heavy industry and transportation. Nations like Australia and Namibia, in turn, have ambitious plans to become exporters of hydrogen—and particularly of green hydrogen, enabled by local advantages in resources like sunlight and wind.

It seems likely that the hydrogen transportation challenge will prove harder to solve—and may demand more radical solutions—for a global green hydrogen economy. Since fossil fuel-based grey and blue hydrogen are more often produced at existing oil and gas facilities, they can more readily take advantage of the cost savings associated with repurposing natural gas pipelines and infrastructure. Producing green hydrogen economically requires its own set of circumstances. It also demands transportation solutions that can bring, say, Australian or African green hydrogen to Europe.

One such solution may currently be underway at Curtin University, where researchers are developing a method for chemically storing hydrogen within a solid sodium borohydride powder for transportation to Japan. A pilot facility in Perth is now under development. If results are good, Australia might just be onto a winner.