Hydrogen can be transported in gaseous or liquid form through different ways such as pipelines, tankers, rail, or barges.
Hydrogen gas transport
Today, hydrogen gas is mainly transported inside cylindrical containers under pressure (typically 200 bar) arranged in a special frame adapted for road or rail transport. The tankers used for this purpose have an overall transport capacity of up to 3600 Nm3. Frames mounted on tanker trucks can also be installed at utilities and used as a stationary storage unit.
Presently, there are some small hydrogen-pipeline systems, up to 200 km, which mainly operates in the United States and Europe and which are used to connect hydrogen production sites to hydrogen utilization sites.
The transport and distribution of hydrogen through pipelines is expected to increase in the coming years, also due to the possibility of using existing natural gas networks with appropriate modifications. Specifically, the embrittlement of materials (steel pipes and gaskets) in contact with hydrogen molecules should be considered, which could lead to increased gas leakages within the hydrogen distribution system. In addition, due to pressure drops, hydrogen gas has to be regularly recompressed by compressor units placed about every 100 meters along the pipeline route.
In general, for the same amount of carried energy, the transport of hydrogen gas through pipelines requires larger pipeline diameters and higher compression energy consumption than natural gas. It is estimated that the cost of transporting hydrogen gas via pipelines on a large scale is about 1.5-2 times higher than that of natural gas. However, for particularly long distances (thousands of km) the transport of hydrogen gas through pipelines is economically competitive with electricity transmission.
Transport of hydrogen in liquid form
Like gaseous hydrogen, liquid hydrogen can be transported by pipelines, tankers or trains.
The use of liquid hydrogen allows to increase the transport capacity of the distribution system but it has some disadvantages such as high investment costs and significant safety issues. The high investment costs are due to the construction of thermally insulated equipment and the installation of cooling systems. Security problems are mainly linked to the risk of burns in case of hydrogen leakage.