Water-Hydrogen Nexus
To produce green hydrogen, electrolysers require not only electricity but also about nine litres of ultra-pure water (H₂O). The amount of raw water may be significantly higher. Especially in water-scarce contexts, the availability of freshwater resources can pose a challenge for electrolysis-based hydrogen production. Often, countries with access to the sea consider the construction of large-scale desalination plants as a key solution, but the implications for nature and people should not be underestimated.
Sustainability Aspects
Water once used in private households or industrial facilities can be recovered, treated and reused. After purification, electrolysers, then, split wastewaters into hydrogen and oxygen. This saves freshwater resources and potentially has a lower socio-environmental impact than seawater desalination. If the structures are suitable, by-products of electrolysis can be used in wastewater treatment plants.
Study Approach
The role of actors, networks and policy instruments in country-specific analyses will deserve special attention to investigate the development and diffusion of water reuse for green hydrogen (WtR4GH2). Research on Technological Innovation Systems (TIS) forms the analytical foundation of this Phd project. Its step-by-step approach will initially cover Germany and other high-income countries but also addresses questions of how water supply for hydrogen production is perceived and managed in middle- and low-income countries.

Thomas Adisorn | Contact: Thomas.adisorn@wupperinst.org, +49 202 2492 246