"Green" hydrogen for ground-based heavy-duty longdistance transportation – A techno-economic analysis of various supply chains

The overarching goal of this paper is an assessment of different supply chains of “green” hydrogen provided for heavy-duty vehicle hydrogen filling stations. Therefore, for different supply chains the estimated energy efficiency and the hydrogen supply cost are compared from well (hydrogen production) to tank (filling station's nozzle) in Germany for the base year 2030. Compressed gaseous hydrogen, liquefied hydrogen, and a liquefied organic hydrogen carrier, namely dibenzyltoluene (DBT), are considered as long distance transport and filling options. Additionally, a local hydrogen production directly at the filling station is assumed beside centralized hydrogen production scenarios for locations in Northern Germany and Algeria. The hydrogen production is based on a PEMelectrolyzer with a location-specific economic optimized photovoltaic and wind power electricity generation. Storage options are gaseous hydrogen pressure tanks and caverns, cryo tanks for liquefied hydrogen, and conventional mineral oil tanks for dibenzyltoluene. Transportation takes place by truck, pipeline, and/or ship. The centralized production in Northern Germany is for each considered supply chain the lowest-cost hydrogen supply option as long as space constraints do not limit onshore wind power installation. Assuming only offshore wind power as a wind energy supply option for Germany, hydrogen production and import from Algeria is more favorable in terms of cost. In general, gaseous hydrogen shows the highest supply efficiency (52 to 68 %), followed by liquefied hydrogen (44 to 55 %) and gaseous hydrogen dehydrogenated from dibenzyltoluene (38 to 43 %). Also in terms of cost, the gaseous hydrogen supply is favorable since liquefied hydrogen (up to +25 %), and gaseous hydrogen dehydrogenated from dibenzyltoluene supply (+50 %) obtain higher costs. Assuming the technical feasibility of a vehicle on-board dehydrogenation of the filled hydrogenated dibenzyltoluene by using the waste heat of the vehicle's hydrogen combustion engine, hydrogenated dibenzyltoluene supply, and direct filling in the vehicle is identified as the option with the highest efficiency and lowest hydrogen supply cost.