Exploring how iron and its oxides can be used as a carbon-free carrier of renewable energy is a complex undertaking in technical, economic, and political terms. The Junior Research Group Integrated Systems Analysis within the cluster project Clean Circles led by apl. Prof. Dr. Kai Schulze investigates how such various perspectives from different disciplines can be integrated and optimized for a multi-criteria systems analysis. To this end, the Junior Research Group leads the interface management between Research Areas 3 (Thermodynamic-mathematical systems analysis) and 4 (Political-economic analysis). The group identifies economic and political criteria, for example political strategies and public funds as well questions of sustainability and regional development, and translates these into relevant variables and indicators, which can be integrated into the thermo-dynamic-mathematical model.