In classical scheduling problems, time goals are the most common objectives. Multi-objective scheduling approaches usually include additional
cost aspects. The expansion of renewable energies influences energy market prices increasingly and, hence, the production costs as
well - this the more the more energy-intensive a production process is. Consequently, in scheduling problems time goals and, in addition,
energy costs should be considered. This is subject of so-called energyefficient scheduling.
Furthermore, besides the concept of energy efficiency, sustainability plays an important role in the economic context. Often sustainability of a production process is measured via its carbon emissions. Therefore, this contribution wants to create twofold transparency by addressing the following questions: What is the meaning of energy efficiency and sustainability in the field of scheduling theory? What is an appropriate mathematical model to combine both perspectives? The discussion of these questions leads to a multi-objective scheduling problem with three conflicting goals - time, costs and emissions. Finally, a small numerical example demonstrates the applicability of the new approach.