[ transport ]
Hydrogen transport technologies compared
When comparing different hydrogen transport technologies , it quickly becomes clear that there is no one perfect solution for all applications . Since each transport technology has specific advantages and disadvantages depending on the application , an agnostic approach in terms of technologies is essential . In addition to the above-mentioned LOHC technology , several solutions are currently in focus of the public discussion .
Compressed hydrogen ( CH 2
) stored in suitable pressure vessels ( e . g ., pressure cylinders ) is already widely used today as a transport technology as well as for mobility . However , it is only cost-effective for very short distances , and the energy input for compression is relatively high , making it unsuitable for international import / export on an industrial scale .
Hydrogen liquefied at -253 ° C ( LH 2
) has a high storage density , is being researched intensively and is already being used in some areas ( e . g ., automotive and aerospace industries ). However , the considerable energy input and high technical expenditure for liquefaction , storage and transport are a challenge , especially for large-scale transport over long distances . LH 2 requires complex infrastructure and costly thermal insulation . At the same time , boil-off , i . e ., evaporation of hydrogen during transfer and storage , is difficult to avoid .
Ammonia ( NH 3
) is used in large quantities in the fertilizer industry . In the future , green hydrogen can be stored in the form of NH 3 and then transported on ocean-going ships approved for chemicals . After transport , the hydrogen molecule can be separated from NH 3 by means of cracking .
However , due to its high toxicity and corrosive properties , ammonia is a very hazardous substance that can only be transported and stored with considerable effort and cost . Long-distance transport of hydrogen in the form of NH 3 to end
Artist ’ s impression of a 1.5 tpd hydrogen LOHC release plant , as planned to be built in Rotterdam , the Netherlands , in 2025 / 2026 . Image © Hydrogenious LOHC Technologies
users is thus made much more difficult . Separating hydrogen from NH 3 also requires a lot of energy at high temperatures , and the cracking technology needed for separation does not yet exist on a large industrial scale . The released hydrogen would also have to be extensively processed to obtain corresponding degrees of purity .
Pipeline-based transport of gaseous , compressed hydrogen makes it possible to transport a large amount of energy relatively safely . For this purpose , either new pipelines must be built , or existing natural gas pipelines must be upgraded . The construction of new pipelines is accompanied by very high investments and a tendency towards negative social acceptance . Converting existing natural gas pipelines must be examined for each individual case . The availability of the necessary compressors for large-scale hydrogen transport is still being researched , and the connection of new consumers is not always possible .
The construction of a European ‘ hydrogen backbone ’ with mainly converted natural gas pipelines for example can advance a Europe-wide connection of hydrogen sources and consumers at a very low cost . However , it can only cover part of the projected transport demand for Europe , as not all sources and consumers can be linked without building new pipelines .
16 Hydrogen Tech World | Issue 9 | April 2023