Hydrogen is one of the alternative energy sources given its clean combustion without carbon emissions and high gravimetric

energy density. However, it is required for the hydrogen to be generated by cleaner pathways rather than the conventional

gas reforming pathway which emits signifi cant carbon. Currently, it is considered that water electrolysis using renewable

energy is the ultimate cleaner pathway of hydrogen production. Unfortunately, given that renewable energy capacity has a

large deviation by the global region and may not meet some regional demands, the international trading of renewable energybased

clean hydrogen will be inevitable. In line with the trend, a case study of introducing clean hydrogen from Australia

in Korea is conducted with economic and environmental impact analyses to indicate its economics and sustainability. In

the pathway of hydrogen introduction, water electrolysis with renewable energy mix, and ammonia are considered as the

hydrogen production way, and hydrogen carrier, respectively.