Environmental evaluation of hydrogen production via thermochemical water splitting using the Cu–Cl Cycle: A parametric study

Variations of environmental impacts with lifetime and production capacity are reported for nuclear based hydrogen production plants using the three-, four- and five-step (copper-chlorine) Cu–CI thermochemical water decomposition cycles. Life cycle assessment is utilized which is essential to evaluate and to decrease the overall environmental impact of any system and/or product. The life cycle assessments of the hydrogen production processes indicate that the four-step Cu–Cl cycle has lower environmental impacts than the three- and five-step cycles due to its lower thermal energy requirement. Parametric studies show for the four-step Cu–Cl cycle that acidification and global warming potentials can be reduced from 0.0031 to 0.0028 kg SO2-eq and from 0.63 to 0.55 kg CO2-eq, respectively, if the lifetime of the system increases from 10 to 100 years.

► Nuclear-based hydrogen production system modelled to investigate environmental impacts.
► Parametric studies have been performed for a diverse range of production capacities and plant lifetimes.
► AP, EP, GWP and ODP values have been evaluated and presented.
► The four-step Cu–Cl cycle has lower environmental impacts than the three- and five-step cycles.