Technical Note : Integration of Power Energy Aspects into the Economic Lot Scheduling Problem

Beck et al. [2019. Integration of energy aspects into the economic lot scheduling problem. International Journal of Production Economics 209, 399-410] extended the Economic Lot Scheduling Problem (ELSP) to account for energy costs as well as tool change and inventory holding costs. In particular, the authors considered the cost arising from the product-dependent energy usage of the production facility during machine startups and shutdowns as well as during tool change, idle, and production phases. This note extends the model proposed by Beck et al. (2019) in two ways: it 1) considers variable production rates and 2) includes power-demand costs, i.e. the energy cost component that depends on the maximum power demand required, thus taking account of a more realistic representation of energy costs in the model.The resulting problem is solved using the common cycle policy, and a numerical experiment is performed to investigate the behaviour of the proposed model. The experiment illustrates that the modified model leads to significant cost savings as compared to the traditional ELSP or the model proposed by Beck et al. (2019), which illustrates the potential usefulness of the proposed approach in practice for reducing energy costs