The SynErgie II project, funded by the German Federal Ministry of Education and Research, ran from 1 November 2019 to 30 June 2023 and focused on the energy‑intensive forging and heat‑treatment facilities at the Schaeffler site in Schweinfurt. The goal was to identify and quantify opportunities for energy flexibility while preserving the stringent quality standards required for these processes. The project was part of the larger Kopernikus programme and involved roughly 60 partners from industry, academia and research institutions, including the Technical University of Munich, Siemens AG and the Fraunhofer Institute. Schaeffler’s own energy management team, linked to maintenance, coordinated the effort and collected the necessary production and performance data.

The technical work was organised into three main work packages. In the first, data were gathered for clusters III, IV and V, with a particular emphasis on the information technology prerequisites for a flexible operation. The second package used the E‑Flex simulation tool to model thermal energy networks. Detailed production and power‑consumption data were processed to reveal the relationship between energy use and process parameters. In the heat‑treatment lines, the four salt‑bath units were modelled as thermal storage. The simulations reproduced the thermal behaviour and power draw of the heating elements with high fidelity. They showed that the salt baths offer substantial flexibility during non‑production periods, but the economic benefit during active production is limited. In contrast, the forging lines, which rely on induction heating, exhibited a near‑linear correlation between the mass flow (hub rate) and power consumption. The simulation accuracy for the forging power draw was within 2 – 4 % of the measured values, indicating that load can be predicted reliably.

The third work package tested the practical feasibility of adjusting process parameters in quality‑critical operations. The temperature of the Martensite and Bainite salt baths, normally set at 200 °C and 220 °C respectively, could be varied between 170 °C and 250 °C. However, the long heating and cooling times—several hours for large temperature shifts—meant that the greatest economic advantage would be realised during off‑peak periods. In the forging plants, experiments altering the order of jobs and adjusting the hub rate were carried out. Both approaches were technically successful under the high quality constraints. Hub‑rate adjustments proved especially attractive, allowing the load to be changed by several hundred kilowatts in less than one minute, thereby providing a rapid response capability for demand‑side management.

Overall, the project demonstrated that the technical prerequisites for energy‑flexible operation exist in both forging and heat‑treatment processes, although organisational and legal issues remain to be resolved. The findings provide a solid basis for further exploration of flexibility potentials in the third funding phase of SynErgie. The results have been documented in a detailed report and are slated for publication in relevant scientific outlets, contributing to the broader effort to align industrial energy demand with the increasingly volatile supply landscape driven by renewable penetration and the phase‑out of coal.