Seaborne imports or domestic production? A techno-economic assessment of hydrogen-based energy carriers

Hydrogen and electro-fuels play a crucial role in decarbonizing hard-to-abate sectors, while the comprehensive cost-effectiveness of their global trade driven by regional cost variations remains underexplored. This study presents a techno-economic assessment of importing hydrogen carriers (liquid hydrogen, liquid methane, methanol, ammonia, and liquid organic hydrogen carriers) via deep-sea shipping, compared with their domestic production. Incorporating country-specific capital expenditures (CAPEX) and weighted average cost of capital (WACC), the production costs of these hydrogen carriers are evaluated through cost-minimizing optimization of capacity configuration and operation strategy for wind-PV-grid hybrid energy systems. Additionally, this study improves shipping cost models by accounting for a comprehensive range of ship types and size categories specific to each hydrogen carrier. For the imports of electro-fuels from China to Sweden during 2025–2050, the levelized import costs of methane, methanol, and ammonia are 98–206, 93–204, and 93–126 EUR/MWh, respectively, which are 12%–22% lower than domestic production costs in Sweden. This cost advantage is attributed to lower country-specific CAPEX and WACC in China, while it comes with higher CO2 emissions due to China's more carbon-intensive electricity grid. However, if electro-fuels require reconversion to hydrogen, the total import costs for all hydrogen carriers exceed the domestic hydrogen production costs. Moreover, if hydrogen production scale is doubled to 200 million kgH2/year, or if shipping distance is reduced to less than 8000 nautical miles, importing liquid hydrogen could become cost-competitive with domestic production. Finally, uncertainty analysis reveals that overall costs are highly sensitive to CAPEX, WACC, and electrolyzer performance, highlighting the significance of accounting for these country-specific factors in global hydrogen trade.