November 2023, a very exceptional convoy crossed the south of Luxembourg from the banks of the Moselle river to transport the new Sotel Réseau transformer to its destination.

This new transformer E receives 220,000 volts and transforms them into 65,000 volts to power, among other things, the four Luxembourg rolling mills of ArcelorMittal and the Differdange electric arc furnace. In addition to the 65,000 volts, a 20,000 volt tertiary winding makes it possible to meet Sotel's own consumption. To ensure security of supply (N-1) for its customers, Sotel has a second transformer, D, installed in 2012.

An adapted transformer

Installed in 1972, the old transformer C had a very limited lifespan. In 2017, oil analyzes showed that it only had 5 years of life expectancy remaining.

The noise constraint was an essential condition of the specifications for the new transformer and the manufacturer's choice fell on the Siemens Energy factory in Linz, Austria, which specializes in low-noise transformers.

To avoid problems on the network, a maximum period of 14 days was imposed on the service provider between the decommissioning of the old transformer and the switching on of the new one. Constraint largely respected with only 12 days of operation of the only transformer available. As additional security, the Sotel lines were temporarily connected to the Creos network.

Commissioning was possible on December 15, 2023 after more than two years of project phase.

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