Decarbonisation Technology August 2022 issue

including storage facilities, without the added complexity or need to mitigate operational/ safety risks. Additionally, the use of existing infrastructure potentially decreases CO₂ emissions as it negates the production effort for new infrastructure. LOHC: a cost-competitive solution Various entities have evaluated several LOHC carriers compared to liquid and gaseous H₂ and ammonia. The section below highlights two such reports: Roland Berger for the EU and the US DOE for North America. Roland Berger assesses three hydrogen carrier technologies – liquefied hydrogen, ammonia, and LOHC – and analyses their costs and feasibility, with a focus on Europe (Roland Berger, 2021). This includes a comprehensive model comparing the cost of ownership of the technologies based on four hydrogen transportation routes that will likely emerge in the future. Choice is dependent on defined use cases, transportation modes, distances, and potential partner synergies. This report concludes that all the technologies still require development work, with ultimate success depending on cost-cutting potential, speed of market uptake, and ease of use. Per this report, for large-scale harbour-to-harbour and mid-scale multimodal transportation, LOHC is cheaper than other carriers and almost comparable to ammonia for small- scale transportation. The transportation could be either inland trucks or intercontinental hydrogen trade using tankers. The US DOE report (Argonne National Laboratory, 2019) compares ammonia and LOHC (specifically toluene/MCH). Hydrogen carrier pathways assume large production plants (hydrogenation) for economy of scale, located in the US Gulf Coast area with a low natural gas price outlook and diverse sources. The reference pathway is hydrogen production by steam methane reforming with comparative production, transmission, and decomposition costs at different demands. The transport assumes by train to storage terminals in California with local transmission by truck at the end. The MCH pathway includes a transmission leg for return of toluene to the production plant. Per this

LOHC (MCH)

Liquid H

Ammonia

Long - term storage and long - distance transportation

Storage density kg H/t of carrier

Handling convenience

-253˚C

Ambient

-33˚C

Limited existing LPG/NH infrastructure

Abundant petroleum infrastructure

Very limited

Existing infrastructure

Highly ammable Can be explosive when mixed with air

Acute toxicity Non- ammable

Slightly toxic Flammable

Safety

Table 1 Comparison of hydrogen carriers

report, NH₃ and MCH are comparable for long-range transport. Additionally, in their Hydrogen Insights report, the Hydrogen Council and McKinsey & Co. estimate that by 2030 the landed cost of H₂ in various ports through LOHC will become competitive with ammonia and liquid H₂ (Hydrogen Council, 2021). LOHC: toluene/MCH technology a derivative from large-scale commercial processes Several organic carrier substances are available, among which toluene, dibenzyl toluene, and benzyl toluene are the most common for LOHC deployment. Toluene as a carrier has many more advantages over other larger molecules, primarily because the available technologies are derived from well- known industrial-scale commercial processes with long track records and the ability to capture large quantities of hydrogen (see Figure 4 ). In addition, as toluene and MCH are more versatile and akin to gasoline, this easily enables the use of existing infrastructure, such as trucks, trailers and vessels, and storage containers. Additionally, Toluene has a much lower pour point and is less expensive than other large molecule-based organic carriers. Toluene and MCH are also more amenable to on-site storage of large volumes with minimum loss. Finally, toluene is available in much larger quantities than other LOHC, which are specialty chemicals produced in limited