The rise in energy costs is putting great pressure on industry to act in order to remain competitive on the global markets. In the area of electricity procurement, energy-flexible factory operation offers a strategy for reacting to rising and volatile electricity prices. Energy flexibility describes the ability to adapt quickly and with little effort to changes in the energy market in order to achieve an economic benefit.

Low electricity price windows should be used intensively and time windows in which the electricity price is comparatively high should be avoided. This requires a great deal of information. In addition to an external information interface for obtaining corresponding price signals, information about the current status of the factory is crucial.

The administration shell

Information from different sources can be merged into a digital twin. The asset administration shell can be used to record and pre-process the relevant information at the respective sources. The asset administration shell serves as an integration layer between the physical and virtual world. For this reason, each asset - including production resources, technical building equipment or products - has its own clearly identifiable asset administration shell.

The digital image of the asset on the asset administration shell comprises both static and dynamic data. Static data includes, for example, manufacturer information and type designations of the asset. The dynamic data includes status data such as the current operating status, energy requirements and order data as well as the description of possible system states that can be triggered, for example to change the energy profile at short notice.

Decisions to change the energy profile are made at the planning and control level. While the administration shell contains the information of an asset, the information of the factory is aggregated at the planning and control level so that correlations between individual assets can also be mapped.

Central monitoring also ensures that no load peaks occur. The digital twin therefore essentially fulfills two functions: monitoring the factory and implementing measures to achieve the desired state. In order to be able to implement a corresponding intervention, the possible measures are presented in an overview to the decision-maker, who selects and implements a suitable measure based on these options.

Benefits of energy-flexible factory operation

The concept described above allows the factory to be operated in an energy-flexible manner, so that energy savings increase the economic efficiency of the factory. Implementations in industry have shown that electricity costs can be reduced by a double-digit percentage.

The use of the asset administration shell also means that other applications can be integrated with little effort. One exemplary application is the automated data analysis of machine behavior, so that the origins of inefficiencies can be identified automatically and at an early stage.

The results were developed as part of the BMBF-funded research project VerEFab - Administration shell for energy-flexible factory operation. At the Fraunhofer Institute for Casting, Composite and Processing Technology IGCV, the project is supervised by Prof. Dr.-Ing. Johannes Schilp and worked on by the scientists Lukas Bank and Christian Härdtlein.