In this paper, the interaction among Time-of-Use (TOU) electricity prices, production scheduling, and preventive maintenance of continuous slurry ball mills is addressed via a hierarchical mathematical modelling framework. Slurry ball mills are considered as the main consumer of electrical energy so that they impose high energy costs on tile factories. However, rarely energy expenses have been taken into consideration in the scheduling. In this study, a mixed-integer energy-cost-aware hierarchical formulation (ECA-H) is proposed and its superiority in terms of various indicators compared to its four possible counterparts is shown. The main contribution of the proposed model in reducing energy costs is obtained by reducing the peak load, and a small share is related to the energy saving. Based on the average of the numerical results, the proposed model compared to its classic counterpart leads to 26% reduction in energy costs, 73% reduction in the peak load, and 3% reduction in the energy consumption. Finally, several easy-yet-effective managerial insights are extracted for mangers to benefit from the findings of our study when they face practical limitations to implement the proposed mathematical model.

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