An electrothermodynamic model is proposed for the carbon anode consumption of the aluminium electrolysis process. Anode consumption produces a primary anode gas composed of CO and CO2. Experimentally, higher electrolysis potentials at the bath/anode interface promotes the formation of CO2 over CO, reducing the carbon consumption at the cost of greater power requirement. Based on the graphenic character of the anode nanostructure, the model successfully predicts this phenomena. The model predicts the charge capture phenomena occurring at the bath/anode interface during electrolysis as a function of the extent of the graphenic crystallites of the carbon anode. Calculated electrolysis CO2/CO ratios are also in good agreement with experimental values. The electrothermodynamic model for the interdependence between the structural, chemical and electrical properties of the anode graphenic crystallites and the primary anode gas CO2/CO ratio could improve industrial optimization of the anode consumption for various nanostructures and interface potentials. For example, it is predicted that increasing the maximal heat treatment temperature of the anode by 100 K (which improves the extent of the graphenic nanostructure) could lower the anode consumption by similar to 6%, similar to experimentally reported values (similar to 9%). (c) 2017 Elsevier Ltd. All rights reserved.