Hydrogen transportation and distribution

Hydrogen needs to be transported and distributed by a reliable delivery infrastructure, proportional to the demand, from the production plant to end-users such as hydrogen refueling stations. Currently, there are three main pathways for hydrogen delivery, tube trailers, and pipelines mainly for the gaseous form of hydrogen, and cryogenic tankers for the liquid form. Pipelines are used to supply high-demand districts and for users such as large industrial users, while tube trailers and medium cryogenic tankers are mainly used for smaller customers and closer distances. However, large cryogenic tankers are used for transport through the sea which is more affordable in comparison to pipeline installments in the marine environment for general export. Several challenges in each pathway should be addressed to reach a sustainable and affordable pathway. Pipeline pathway challenges are its high cost, probability of leakage, hydrogen embrittlement (HE) of steel pipelines, problems in geological storage such as contamination and leak, selection of preferred pipeline route, and monitoring and maintenance. Tube-trailers pathway challenges are the necessity of high resistance tubes and reliable compressors to reach desired high loading pressure and high storage cost. Cryogenic tanker pathway challenges are cost, specialized liquid hydrogen ship, boil-off at tank wall and during unloading at the refueling station, and high cost to reach very low temperature. There is another pathway for hydrogen transportation with so-called carrier materials. These are synthetic chemicals such as methanation, ammonia, liquid organic hydrogen carriers (LOHC), and metal hydrides. These materials for hydrogen transport and metal hydrides are in the technology development stage for commercialization. The safety issue is an integral part of all pathways which is related to the physical and chemical properties of hydrogen; especially issues related to untrained people refueling cars and domestic consumption. The pipeline is likely to be the safest and most economical way of hydrogen distribution considering the lower likelihood of accidents and exposure to humans. In this chapter, in addition to providing information regarding various pathways, environmental impact, cost, policies, and safety issues, a hydrogen transportation model is proposed which can be used to optimize the total cost of hydrogen delivery from several hydrogen production plants to end-users.