Power-load management reduces energy-dependent costs of multi-aisle mini-load automated storage and retrieval systems

For economic and ecological reasons, the interest in the energy demand of material-handling systems is rising. As a result, the operators of these systems increasingly pay attention to the energy demand and the costs resulting from it. The energy demand of automated warehouses, with multi-aisle automated storage and retrieval systems, is volatile with uncontrolled power-peaks. These power-peaks result in high energy and hardware costs. In this paper, the effect of a power-load management on the throughput of the material-handling systems is investigated. We assume that the peaks of energy consumption can be significantly reduced by delaying tasks, without having an impact on the throughput. The goal is to find out the interdependence between the electrical power-limits of the power-load management (mean power demand in a period and maximum power demand) and the throughput of the warehouse. The results show that, with a maximum power-limit and a mean power-limit, the peaks in energy consumption can be avoided with only a slight loss of throughput. Load management is an effective method to reduce the energy peaks of an automated warehouse, thereby lowering the costs of automated warehouses.