Hydrogen is a $183 billion dollar industry as of 2022. [1] The production of hydrogen supports some of the most crucial industries such as agriculture and petrochemical industry. While the usage of hydrogen has many potential benefits to minimize our dependence on fossil fuel, it is the smallest and lightest element in the universe; making it a critical challenge for transportation and delivery. Due to regional availability of resources, technology and infrastructure, and the imbalance of demand and supply; millions metric tons of hydrogen are transported all around the world every year as opposed to producing locally.

Global hydrogen production is expected to reach 240 million metric tons per year by 2040, doubling the current hydrogen production today. [2] In figure 1 from IRENA’s report [3], we can see how interdependent and interconnected the world’s hydrogen imports and exports are. The longest route of transport on the map is the port of Rotterdam in the Netherlands to Australia that spans 23,957 kilometers and other shipping routes ranging between 5,000-7,000 kilometers. With new hydrogen policies, agreements, and roadmaps; the main challenge that could hinder the new hydrogen economy could be solving the issue of hydrogen transport. In this thought piece, we will compare the different methods of transporting hydrogen, its drawbacks, and its potential future to enable the global hydrogen industry. 

Figure 1. Bilateral trade announcements for global hydrogen trade until March 2022 [3]

Comparison Metrics

We will explore the different methods of transporting hydrogen and do a comparison between all the methods in three categories:

• Economic viability: What is the levelized cost of transporting hydrogen using this method? What is the cost of infrastructure to adopt this method? What is the potential cost efficiency in the future if adopted at scale?

• Readiness of technology: Is this technology ready to be deployed in the next 1 to 3 years? What is the bottleneck that is stopping it from being adopted? Has there been a proven concept of this technology?

• Scalability: Can we scale this technology that would meet the hydrogen demand of the future?

Hydrogen Methods of Transportation

With the rubric to compare the different methods set; here are the hydrogen transportation methods that we will dive deeper into:

• Gaseous:

  • Compressed Gaseous Hydrogen Tanks

  • Pipelines

• Liquid:

  • Cryogenic Transportation

  • Ammonia as a Carrier

  • Liquid Organic Hydrogen Carriers (LOHCs)

Figure 2. Scope of modeling frame work (blue boxes) used for global hydrogen [3]

Hydrogen Pipelines

Currently, there are 1,600 miles (2,574.95 kilometers) of purpose pipelines for hydrogen in the United States [4] and approximately 13,760.51 miles (22,145.4 kilometers) in the EU with Germany leading 2,377.99 miles (3,827 kilometers) [5]. Hydrogen pipelines are by no means new ways of transporting hydrogen. The very hydrogen pipeline was built in 1938 that spans 240 km long in the largest metropolitan region of Germany, Rhine-Ruhr [6]. It was built out of steel pipe to transport compressed hydrogen at 10-20 bar of pressure with a diameter of 25–30 cm. The length of hydrogen pipelines might sound massive in isolation but to put things in perspective, the US has over 3 million miles [7] and the EU has over 2 million miles of natural gas pipelines [8].

Economic Viability

The operating cost of transporting hydrogen through pipelines is by far the cheapest way to transport hydrogen. Pipelines are best used for last-mile transportation of below 500 km where prices of transporting hydrogen can be below 0.1 USD/kg [9]. The challenge comes into hand when considering the lack of current infrastructure for hydrogen pipelines, meaning either new purpose pipelines have to be built or retrofitting existing pipelines for hydrogen transportation. Retrofitting existing pipelines for onshore transmission, subsea transmission, and distribution pipelines can cost $600K to $1.2M, $1.3M to $3.1M, $100K to $200K, respectively, per kilometer of pipelines. Whereas, building new pipelines for onshore transmission, subsea transmission, and distribution pipelines can cost $2.4 to $4.5M, $4.7M to $7.1M, $300K to $700K, respectively, per kilometer of pipelines. [9] With many pipeline projects confirmed, it is not surprising that the price tag of these developments usually starts in the billions of dollars.

Figure 3. Comparing Hydrogen Pipelines [9]

Technological Readiness

Hydrogen pipelines are not new, there are ready-made and deployable technologies out there. But companies and researchers are still battling to reduce permeation rates and to ensure better containment in the pipelines. Companies such as ADNOC (Abu Dhabi National Oil Company) and their research center ADRIC have partnered with TWI to form NIC (Non-metallic Innovation Center) look into new ways to coat existing pipelines to improve performance for hydrogen transportation.

One thing we should note is that the permeation/ leakage of hydrogen not only has economic and safety implications, but also environmental ramifications. A study led by the CICERO Center for International Climate Research published in 2023, have shown that hydrogen has a GWP100 of 11.6 ± 2.8 (one standard deviation). GWP100 of 11.6 can be translated to: the warming effect of 1 metric ton of hydrogen over 100 years is equivalent to the warming effect of 11.6 ± 2.8 metric tons of CO2 in the atmosphere. [10]

Scalability

Scaling hydrogen pipelines is not an easy challenge to tackle. Building new pipelines takes time and costs a lot of money, especially large-scale pipelines onshore and in the ocean. One factor that could hasten this process and make it cheaper is using the existing 3+ million miles in the US and 2+ million miles in the EU of natural gas pipelines to accommodate for hydrogen. As hydrogen molecules are much smaller than natural gas (CH4) and are usually transported at a higher pressure than existing pipelines, they are limited to only blend with 6% or lower in the pipeline for safety purposes. [11] A study led by Dr. Arun SK Raju and Dr. Alfredo Martinez-Morales from UC Riverside has found that “for a gas blend containing 10% hydrogen, the expected increase in (leak) flow rate is 5% compared to pure methane, while for a 20% hydrogen gas blend, the increase in leak flow rate is 10%.” [12] This leakage issue poses both safety and environmental concerns. Here you can find the current hydrogen blending limit in existing natural gas pipelines in selected countries. Thus, for higher hydrogen content to be transported in a blended pipeline, retrofitting and upgrading existing infrastructure must take place with the aforementioned economic cost in the economic viability.

Compressed Gaseous Hydrogen Tanks

According to the DOE’s Office of Energy Efficiency & Renewable Energy, gaseous hydrogen is the most common way of transporting hydrogen today [13]. Most hydrogen is produced at 20 to 50 bar of pressure and must be compressed further to 180 bar or higher for better economics in storage and transportation. Compressed gaseous hydrogen gas tanks are mainly transported on the road by trucks, also called tube trailers, or in pipelines which we explored above.

Economic Viability

According to a report from Hydrogen Insight and McKinsey & Company, the cost of transporting compressed gaseous hydrogen gas tanks from 0 km to 100 km is between 0.1-1 USD/kg and 100 km to 500 km is between 1-2 USD/kg. [9] Compared to transporting through pipelines, this is much more expensive. The reason why this is the most common way of transportation is that most companies can purchase a trailer on a semi-truck for hydrogen, which ranges between 50,000-100,000 USD per trailer, is much cheaper in capital expenditure than spending billions of dollars and years to build new infrastructure to bring down the OPEX significantly.

Figure 4. Bilateral trade announcements for global hydrogen trade until March 2022 [9]

Technological Readiness

The hydrogen tube trailer market is worth 276.3 Million USD in 2020 [14]. Being the most common way of transportation especially for short distances (<500 km), the technology for transporting gaseous hydrogen is readily available. The challenge arises when the quantity of hydrogen transported is large and/or at longer distances. Which leads us to the last question of its scalability.

Scalability

A 42,000-liter tube trailer used for, assuming that the hydrogen is stored at 200 bar - 14.94kg/m3 [15] would carry around 628 kg of hydrogen. Stored in liquefied state the same trailer could carry 2,980 kg of hydrogen. Using ammonia as a carrier and assuming 80% recovery rate, it would be able to carry 3,656 kg of hydrogen [16]. For a shorter distance, the price difference might not be much. If you’re looking to transport hydrogen from Sydney to Rotterdam, the additional cost of a more gaseous tank on a 20,000 km trip would be exponential. Since we are looking at the global hydrogen economy, this is where compressed gaseous hydrogen tanks fall short.

Cryogenic Transportation

Cryogenic transportation refers to the transport of hydrogen in its liquid state. “Hydrogen has the second lowest boiling point and melting points of all substances, second only to helium.” [17] The boiling point of hydrogen is at −253°C (−423°F). Without the availability of pipelines, liquid hydrogen is the most preferred method of transporting hydrogen at high volumes.

Economic Viability

A study done by the US Department of Energy in 2019 has estimated that a dispensed fuel-grade hydrogen at the pump would cost about 14.25 USD/kg. [18] The 700-900% increase in price at the pump is mainly due to the cost of liquefaction, the demand for extremely well-insulated tanker trucks, and the evaporation loss of hydrogen during transport. From the same study, the cost of a hydrogen plant is “estimated to range from $50 million to $800 million for capacities ranging from 6,000 kg/day to 200,000 kg/day, respectively,” with the cost of energy consumption ranging between $1.70 to $1.81 per kg of hydrogen depending on the scale of the liquefaction.

Figure 5. Average Liquefier Energy Requirement by Capacity [18]

Additionally, there is a high transportation price of 1-2 USD/kg by truck within 500 km and 1-2+ USD/kg by ship traveling 1000 km to 5000+ km due to a need for a well-insulated method of storage.

Technological Readiness

Efficiency of liquefaction of hydrogen and storage with hyper-insulation to avoid evaporation of liquid hydrogen is the major challenge that the industry is facing. Kawasaki has completed their technological development of their cargo containment system (ccs) and has also received approval in principle from the classification society ClassNK for their LH2 tankers in 2023. [19] This project aims to build a liquid hydrogen tanker consisting of 4 of the ccs units (40,000 m3 each) allowing the ship to carry 160,000 m3 of hydrogen. In terms of adopting liquid hydrogen as a main method of transporting hydrogen, new technologies will be the main enabling factor.

Scalability

Compared to compressed gaseous hydrogen, liquid hydrogen has a much higher density and is great for large scale hydrogen transportation. Due to the extremely low temperature of liquid hydrogen, scaling the infrastructure poses strong technological and economic challenges. That being said, it is still one of the main methods of transporting large quantities of hydrogen today, be it on a truck or on a tanker.

Ammonia as a Carrier

Following the invention of the Haber process in 1918 and the Haber-Bosch process in 1931, ammonia (NH3) production has been industrialized and produced in large volumes. [20] The Haber-Bosch process is a reversible process, allowing companies to transport hydrogen through ammonia and cracking the ammonia for hydrogen at the receiving plant.

Economic Viability

Ammonia is a USD 205.34 billion industry [21] and 239.41 million metric tons of ammonia were produced in 2022. [22] This means that it is a mature industry and there is infrastructure, shipping vessels, and processing facilities that are ready for the industry to utilize it for transporting hydrogen. Here is a cost breakdown of transporting hydrogen compiled from an article published in the International Journal of Hydrogen Energy [23]:

Note on the costing breaking table:

• The study only takes into account the intermediate cost of storage prior to shipping, transportation cost via shop, and the intermediate cost of storage after shipping.

Figure 6. Boundary conditions for the modelling transportation costs. Note that hydrogen carrier conversion and reconversion is not considered in this study. [23]

• All costs are calculated of transportation cost from Rotterdam to Australia (10,850 nautical miles)

Figure 7. Table of price comparison between Rotterdam and Australia without conversion and reconversion cost. [23]

With the aforementioned conditions, ammonia is the cheapest at only $0.56/kg of hydrogen. Whereas exhibit 12, which takes all costs into consideration, the cost of transporting hydrogen through ammonia quickly became one of the most expensive methods of transportation at 1-2 USD/kg (above 1,000 km) and >2 USD/kg (above 5,000 km). For ammonia to be an effective carrier for hydrogen transportation, ancillary costs must come down drastically. Figure 3.5 from Irena’s report shows the prediction of cost reduction in hydrogen transportation using ammonia to bring it down to sub 1 USD/kg. [3]

Figure 8. Factors contributing to the reduction of ammonia transport cost [3]

Technological Readiness

Producing ammonia and reversing the process to do ammonia cracking is a well-studied process. Shipping vessels that are available today can carry large amounts of ammonia. Maersk has placed an order to receive 4 large ammonia tankers carrying 93,000 m3 of ammonia (11,160,000 kg of hydrogen), and is ready to be delivered by 2026. [24] There are also large ammonia tanks and infrastructure for these tankers to offload ammonia. From figure 3.5, we can clearly see that units of scale and increased knowledge in cracking will enable ammonia to be a low-cost method of transporting hydrogen. All the reasons mentioned above allow ammonia to be a great alternative as it requires significantly less up-front investments in order to kickstart the immense need for global hydrogen trade.

Scalability

Unlike liquid hydrogen, liquid ammonia can be transported at -33 °C or at ambient temperatures under a pressure of 8-10 bar. [25] Main concerns of ammonia are that ammonia is a toxic chemical. According to the New York State Department of Health, “Exposure to high concentrations of ammonia in the air causes immediate burning of the eyes, nose, throat and respiratory tract and can result in blindness, lung damage or death.” [26] Unlike the previous methods, hydrogen from ammonia cracking must undergo a purification process whether through pressure swing adsorption, cryogenics, and membranes such as DIVI-H.

Liquid Organic Hydrogen Carriers (LOHCs)

LOHCs out of all the potential ways to carry hydrogen is the newest solution and the technology is evolving very quickly. Both large and small corporations are attempting to prove the advantage of numerous materials for this purpose. The information reflected in this paper might therefore become rapidly obsolete as companies improve and increase in their product performances.

Liquid organic hydrogen carriers or LOHCs are organic compounds that can absorb and release hydrogen through the help of heat, pressure, and a catalyst. Some common LOHCs are toluene and dibenzyltoluene, but there are many other chemical compounds that companies are experimenting with. The liquid toluene or dibenzyltoluene will absorb the hydrogen atoms with the help of a catalyst at 25-50 bar. The hydrogen atoms can be separated from the LOHCs through heating it up to around 300°C at 1-3 bars of pressure. [27]

Economic Viability

LOHCs can have a fairly high concentration of hydrogen. A benzyltoluene as an LOHC has volumetric storage density 54 kg hydrogen per m³ of LOHC and best case up to 56 kg. [28] In comparison, gaseous hydrogen at 200 bar has 14.94 kg and liquid hydrogen at 70.96 kg of hydrogen per m³. [15] The high cost of transporting hydrogen through LOHC is mainly due to the hydrogenation and the dehydrogenation process to attach and detach hydrogen from the LOHC especially in large quantities. Additionally, the hydrogenated hydrogen must also go through a hydrogen purification process.

Technological Readiness

Emerging companies like Hydrogenious (benzyltoluene - C14H14), OCOchem (formic acid - CH₂O₂), and Chyoda’s SPERA Hydrogen (methylcyclohexane - C7H14) have taken the lead in exploring and enhancing their LOHC technology for safer and more efficient hydrogen transportation. Currently, there are commercially available services and products ready to assist companies in transporting hydrogen through LOHCs. The technology was initially proposed in 1975 [29], and we have already witnessed products that could revolutionize the entire industry. Many researchers and companies alike are eager to witness the emergence of new technologies related to LOHCs in the near future. 

Scalability

LOHCs resemble a diesel-like substance, and the existing infrastructure for fossil fuels can easily be repurposed for transporting LOHCs at atmospheric pressure and ambient temperature. Hydrogenious has claimed and demonstrated that their LOHC is "hardly flammable with a flashpoint of 112.5 °C, non-explosive, even when loaded with hydrogen". [28] In comparison to ammonia, LOHCs are considered much safer for handling the compound. As the conversion process becomes increasingly affordable, LOHCs are undeniably strong contenders to become the primary method of hydrogen transportation.

Conclusion

As we aim to reduce dependence on fossil fuels, addressing the critical challenge of hydrogen transportation is imperative for us to prepare for a future hydrogen economy. Evaluating using the framework of economic viability, technological readiness, and scalability of different hydrogen transportation methods provides us with a better understanding and creates an apple to apple comparison of these technologies. The bottom line is that there is not a “one size fits all” solution in transporting hydrogen. Each technology has its own advantages and disadvantages depending on their specific application, infrastructural and economical context, and their potential in the future to rapidly grow. Here’s a quick overview of all the different methods of transportation:

Figure 9. Table comparison between hydrogen transportation methods of their advantages and disadvantages

We have been pushing in finding new ways to effectively produce green and blue hydrogen at scale, and it must go hand in hand with our focus in developing the technology as well as the infrastructure to support the large transportation of hydrogen in the near future.

References:

[1] Industrial Hydrogen Global Market Value 2032 , Statista. (2023). https://www.statista.com/statistics/1411810/global-market-value-of-hydrogen-industry/#:~:text=The%20global%20hydrogen%20industry%20was,billion%20U.S.%20dollars%20by%202032. (accessed March 6, 2024). 

[2] A. Čučuk, Hydrogen production to increase to 110 MT per year by 2030, study says, Offshore Energy. (2023). https://www.offshore-energy.biz/hydrogen-production-to-increase-to-110-mt-per-year-by-2030-study-says/ (accessed March 6, 2024). 

[3] Global Hydrogen Trade to meet the 1.5°C climate goal, IRENA. (2022). https://www.irena.org/-/media/Files/IRENA/Agency/Publication/2022/Jul/IRENA_Global_hydrogen_trade_part_1_2022_.pdf 

[4] Hydrogen Pipelines, Energy.Gov. (n.d.). https://www.energy.gov/eere/fuelcells/hydrogen-pipelines 

[5] A. 25, Europe: Hydrogen Pipeline length by country 2023, Statista. (2023). https://www.statista.com/statistics/1389658/proposed-hydrogen-pipeline-infrastructure-length-in-europe-by-country/ 

[6 ]Hydrogen Pipeline Transport, OilfieldWiki. (n.d.). http://www.oilfieldwiki.com/wiki/Hydrogen_pipeline_transport 

[7] U.S. Energy Information Administration - EIA - independent statistics and analysis, U.S. Energy Information Administration (EIA). (n.d.). https://www.eia.gov/energyexplained/natural-gas/natural-gas-pipelines.php#:~:text=The%20U.S.%20natural%20gas%20pipeline,and%20storage%20facilities%20with%20consumers.

[8] Gas factsheet - Key Facts about gas in the EU, ACER - European Union Agency for the Cooperation of Energy Regulators. (n.d.). https://www.acer.europa.eu/gas-factsheet#:~:text=The%20EU%20gas%20network%20is,compressor%20and%20pressure%20reduction%20stations. 

[9] Hydrogen Insights A perspective on hydrogen investment, market development and cost competitiveness, Hydrogen Council. (2022). https://hydrogencouncil.com/wp-content/uploads/2021/02/Hydrogen-Insights-2021.pdf 

[10] M. Sand, R.B. Skeie, M. Sandstad, S. Krishnan, G. Myhre, H. Bryant, et al., A multi-model assessment of the global warming potential of hydrogen, Communications Earth &amp; Environment. 4 (2023). doi:10.1038/s43247-023-00857-8. 

[11] Iea, Current limits on hydrogen blending in natural gas networks and gas demand per capita in selected locations – charts – Data & Statistics, IEA. (2019). https://www.iea.org/data-and-statistics/charts/current-limits-on-hydrogen-blending-in-natural-gas-networks-and-gas-demand-per-capita-in-selected-locations.  

[12] A.S. Raju, A. Martinez-Morales, The California Public Utilities Commission, 2022.

https://docs.cpuc.ca.gov/PublishedDocs/Efile/G000/M493/K760/493760600.PDF 

[13] Gaseous hydrogen delivery, Energy.Gov. (n.d.). https://www.energy.gov/eere/fuelcells/gaseous-hydrogen-delivery    

[14] Hydrogen tube trailer market size, share, trends, analysis 2026, Fairfield Market Research. (2020). https://www.fairfieldmarketresearch.com/report/hydrogen-tube-trailer-market 

[15 ] Hydrogen data - hyjack : Hydrogen online, Hyjack. (n.d.). https://hyjack.tech/hydrogen-data 

[16 ] Ammonia: Fuel vs. Hydrogen Carrier, Black & Veatch. (n.d.). https://www.bv.com/perspectives/ammonia-fuel-vs-hydrogen-carrier/#:~:text=This%20same%201%20ton%20of,energy%20production%20of%2016%2C626%20MJ 

[17] Module 1 hydrogen properties, Energy Efficiency and Renewable Energy. (2001). https://www1.eere.energy.gov/hydrogenandfuelcells/tech_validation/pdfs/fcm01r0.pdf 

[18] E. Connelly, M. Penev, A. Elgowainy, C. Hunter, Current status of hydrogen liquefaction costs, DOE. (2019). https://www.hydrogen.energy.gov/docs/hydrogenprogramlibraries/pdfs/19001_hydrogen_liquefaction_costs.pdf?Status=Master 

[19] F. Bahtić, Khi: Tech Development of CCS for Liquid H2 carriers completed, Offshore Energy. (2023). https://www.offshore-energy.biz/khi-tech-development-of-ccs-for-liquid-h2-carriers-completed/ 

[20] Haber-Bosch process, Encyclopædia Britannica. (2024). https://www.britannica.com/technology/Haber-Bosch-process

[21] Ammonia market size, share & growth trends report, 2030, Grand View Research. (n.d.). https://www.grandviewresearch.com/industry-analysis/ammonia-market#:~:text=The%20global%20ammonia%20market%20size%20was%20estimated%20at%20USD%20205.34,USD%20213.9%20billion%20in%202023 

[22] N. 24, Global Ammonia annual production capacity, Statista. (2023). https://www.statista.com/statistics/1065865/ammonia-producthttps://www.statista.com/statistics/1065865/ammonia-production-capacity-globally/#:~:text=The%20global%20production%20capacity%20of,million%20metric%20tons%20by%202030.ionhttps://www.statista.com/statistics/1065865/ammonia-production-capacity-globally/#:~:text=The%20global%20production%20capacity%20of,million%20metric%20tons%20by%202030.capacity-globally/#:~:text=The%20global%20production%20capacity%20of,million%20metric%20tons%20by%202030. 

[23] C. Johnston, M.H.A. Khan, R. Amal, R. Daiyan, I. MacGill, Shipping the sunshine: An open-source model for costing renewable hydrogen transport from Australia, International Journal of Hydrogen Energy. (2022). https://www.sciencedirect.com/science/article/pii/S0360319922017281#fig1 

[24] P. Martin, Maersk Orders World’s biggest ammonia carriers from Hyundai to ship hydrogen derivative across oceans, Hydrogen News and Intelligence | Hydrogen Insight. (2023). https://www.hydrogeninsight.com/transport/maersk-orders-worlds-biggest-ammonia-carriers-from-hyundai-to-ship-hydrogen-derivative-across-oceans/2-1-1563932 

[25] Hydrogen Transportation: Three well-known energy carriers compared, Demaco Cryogenics. (2023). https://demaco-cryogenics.com/blog/hydrogen-transportation-three-energy-carriers/ 

[26] Department of Health, The Facts About Ammonia. (n.d.). https://www.health.ny.gov/environmental/emergency/chemical_terrorism/ammonia_general.htm 

[27] H.G. Shiraz, M. Vagin, T.P. Rouko, V. Gueskine, K. Karon, M. Lapkowski, et al., Towards electrochemical hydrogen storage in liquid organic hydrogen carriers via Proton-coupled electron transfers, Journal of Energy Chemistry. (2022). https://www.sciencedirect.com/science/article/pii/S2095495622003229 

[28] Hydrogenious - How, Hydrogenious LOHC Technologies. (2024). https://hydrogenious.net/how/ 

[29] C. Chu, K. Wu, B. Luo, Q. Cao, H. Zhang, Hydrogen storage by liquid organic hydrogen carriers: Catalyst, renewable carrier, and Technology – A Review, Carbon Resources Conversion. (2023). https://www.sciencedirect.com/science/article/pii/S2588913323000248