In the field of logistics, the topic of energy efficiency and sustainability has increasingly been in the general focus in recent years. This trend, called "Green Logistics", is favoured by rising energy costs and stricter legal requirements. Efficiency is generally understood to mean the relationship between benefits and costs. The benefits of a storage and retrieval machine are not yet precisely defined and are the subject of the research project. In addition to the throughput, other components still to be determined are included in the benefit. In the broadest sense, the effort is equated with the energy requirement. The energy requirement for the operation of stacker cranes has been the subject of various research projects in recent years. It can be determined by analytical calculation, numerical simulation or measurements. Binding guidelines or regulations for the measurement or calculation of energy demand are not yet available for stacker cranes. Such guidelines for energy efficiency classes have so far only been established in the field of passenger lifts.
In order to be able to assess the energy efficiency of a stacker crane quickly and comparably, a key figure-based approach is required which makes it possible to compare a wide variety of equipment with each other. For this it is necessary to consider important parameters which influence the energy demand and the benefit of the device according to the magnitude of their influence. Both the benefit and the energy demand of stacker crane determined by a large number of different and partly interdependent influencing factors.
The main objective of the proposed research project is the development of a classification system that enables the evaluation of the energy efficiency of storage and retrieval machines. In addition, key figures for the evaluation of individual subsystems of a storage and retrieval system are being worked on. These should provide only one measure of the efficiency of a subsystem, e.g. lift or travel drive.
The first step is to research and compare different approaches to energy efficiency assessment. Subsequently, the various influencing factors on energy demand and performance of stacker cranes are compiled and compared by means of a weighted evaluation. This forms the basis for deriving the energy efficiency index. In order to be able to determine these classes more easily, representative load cycles are determined. These load cycles allow a quick determination of the average energy demand and the benefit of the stacker crane. These data are used to form a key figure for characterizing the energy efficiency of a stacker crane.
Finally, the findings are validated by extensive measurements and implemented in a software demonstrator. The early cooperation with the industry ensures the broad dissemination of the research results and the highest possible acceptance of the energy efficiency classes.
- Gebhardt Fördertechnik GmbH
- ifp consulting GmbH & Co. KG
- Jungheinrich Logistiksysteme GmbH
- LTW Intralogistics GmbH
- TGW Mechanics GmbH
- Schenker Deutschland AG
- SSI SCHÄFER
- Weissenborn Logistik-Consulting
- VDI-Gesellschaft Produktion und Logistik
The research has been conducted within the Industrielle Gemeinschaftsforschung [collective industrial research] (IGF) project “Entwicklung einer Bewertungsmethodik für die Energieeffizienz eines Regalbediengerätes” (IGF project number 18839N). This project has been funded by the Federal Ministry for Economic Affairs and Energy on the basis of a decision of the German Bundestag [Federal Parliament].