Technological watch

Low?consumable nickel ferrite?based anodes for the Hall–Héroult process are compared with conventional prebaked carbon anodes using thermodynamic simulation and prospective life cycle assessment under contrasting future electricity system pathways from 2025 to 2050. The analysis quantifies energy requirements and environmental burdens under evolving power systems, identifying long?term emission mitigation potential and material demand trade?offs for sustainable primary aluminum production.Aluminum production via the Hall–Héroult process is characterized by high energy consumption and significant greenhouse gas emissions, primarily due to the use of consumable carbon anodes. This study investigates the thermodynamic behavior, energy demands, and environmental implications of transitioning to low?consumable (LC) NiFe2O4–NiO–Ni–Cu?based anodes as a strategy for decarbonizing primary aluminum production. To assess sensitivity to upstream energy supply, the study compares the evolution of German and Norwegian electricity systems from 2025 to 2050, starting from Germany's currently more carbon?intensive mix and Norway's predominantly renewable system. Although LC anode production is more energy?intensive (2.1 vs. 0.99?kWh/kg), their long service life reduces specific energy use to 0.00021?kWh/kg Al versus 0.44?kWh/kg Al. However, increased bath voltage raises the net electricity demand by ?2.8?kWh/kg Al. Life cycle assessment (LCA), using foreground thermodynamic simulation data and background data from ecoinvent v3.10, was performed to quantify global warming potential (GWP), acidification (AP), and material resources: metals/minerals (MRD). Results indicate that, in a German scenario, the use of LC anodes reduces environmental impacts by up to 8% in GWP, 20% in AP, although they increase MRD by ?10% compared to prebaked anodes. Decarbonizing the electricity supply, modeled using Norway's energy mix, yields GWP reductions exceeding 50%. Furthermore, a prospective LCA was conducted with Premise and Brightway, integrating future energy pathways from the Regional Model of Investments and Development integrated assessment model under the Shared Socioeconomic Pathway 2—Base and the Nationally Determined Contributions (NDC) scenarios for 2025–2050. In Germany, LC anodes under NDC policies reduce GWP by up to 76% and AP by 56% by 2050 compared to 2025, although MRD increases by a factor of 2.06. In Norway, the reductions are smaller but still meaningful, with GWP and AP decreasing by ?50%, while MRD declines by 33% by 2050 relative to 2025. This integrated analysis highlights LC anodes potential for aluminum decarbonization while revealing trade?offs between emissions and resource demand. Future research should address cell design, electrolyte optimization, and circular strategies to limit energy and material pressures. LC anodes, especially with clean electricity, can be a cornerstone of sustainable aluminum production.