During the first part of the project, MATERIALIZE has made substantial progress in developing new methods to quantify and model the demand for critical materials under future energy system transitions. These methods were applied to key technologies such as electrolysis, batteries, and photovoltaic supply chains.
The starting point of MATERIALIZE marked the development of ETHOS.ReFlow a lightweight resource flow model designed to support in-depth case studies of energy technologies. Initial applications included proton exchange membrane (PEM) electrolysis, battery storage, and water demand of electrolysis. For PEM electrolysis, ETHOS.ReFlow was used to evaluate global iridium requirements under different climate pathways, incorporating dynamic catalyst loadings, recycling efficiencies, and competing sector demands. In parallel, the tool was applied to battery technologies, including lithium-ion, sodium-ion, and solid-state variants, capturing circular economy dynamics such as second-life deployment and recycling. A physically grounded water model was also developed to simulate water demand of electrolysis, accounting for stoichiometric and thermal losses under site-specific meteorological conditions. These efforts provided high-resolution material and water demand datasets now used in broader system modelling and highlighted emerging bottlenecks in resource-constrained transition pathways.
In addition, initial research has begun on out-phased materials such as gypsum, a by-product of coal-based flue gas desulfurization, which may become scarce as fossil fuel use declines. A material flow analysis is under development to trace alternative gypsum sources and assess regional supply risks.
To further improve realism in energy modelling, a robust optimization method was introduced. This method stress-tests energy systems across multiple weather years to identify critical shortfalls (e.g. during cold dark lulls) and integrates representative stress periods back into the model through time-series clustering. This allows for the design of energy systems that are resilient not only under average but also extreme conditions.
Finally, MATERIALIZE has made significant progress toward embedding material flow constraints directly into the open-source optimization framework ETHOS.FINE. A modular extension named ETHOS.FINE.Resources enables the co-optimization of energy and material flows by linking material consumption to infrastructure commissioning and recycling to decommissioning. While the core architecture has been implemented and validated in test systems, further refinement and large-scale integration are ongoing. This development represents a major methodological advance, enabling resource-aware planning under real-world constraints.
