A smart grid for Wachtendonk, Germany

Wachtendonk, Germany


SWK Stadtwerke Krefeld AG is a publicly owned multi-service provider in North Rhine-Westphalia, Germany. It serves the 8,000-strong community of Wachtendonk, where about 80 percent of the electricity is generated by decentralized energy sources, primarily photovoltaic panels.   While the integration of renewable energy is in line with the so-called “energy transition”, distribution grids are usually not prepared for the high infeed of volatile energy sources that can produce very strong voltage fluctuations and cause instability, shortages, and overloads.   To keep the distribution grid stable despite the high percentage of electricity coming from renewables, SWK Stadtwerke Krefeld AG was looking for a way to cost-efficiently modernize the grid.
Wachtendonk is a very small community with a large number of energy suppliers – primarily photovoltaic stations. Unfortunately, these suppliers also produce very strong voltage fluctuations.
Carsten Liedtke, Chairman of the Board, SWK Stadtwerke Krefeld AG


Siemens and SWK Stadtwerke Krefeld AG will transform the existing power supply system in Wachtendonk into a smart grid for research purposes.

As part of the project, Siemens Smart Grid is installing smart meters in about one hundred homes and many distribution boxes. Their function is to collect the status-related data needed to operate a smart grid. The smart meters feature a special add-on function known as the power snapshot analysis: It enables snapshots of key parameters and turns the devices into “eyes” for monitoring grid activity.

Five new intelligent secondary substations will also act to ensure greater stability. Their function, among other things, is to compensate for voltage dips, which can result when clouds form over the solar panels in Wachtendonk. The substations are equipped with communications-capable medium-voltage switchgear, adjustable local transformers, and remote-control and distribution grid automation components.


One of the advantages of the project will be the acquisition of detailed information about the behavior of a smart distribution network. In addition, new technical components will be tested in everyday use, which will provide insights useful for the further development of the smart grid.   Additionally both the technical and commercial concepts of this pilot project can serve later as a model for other public utility companies.   SWK Stadtwerke Krefeld AG will be able to avoid investing in immediate grid extensions despite the high feed-in from renewable energy sources.   At the same time an additional grid capacity of approx. 35 percent will be gained.   Furthermore saving potentials can be easily identified and any future grid extensions will be based on reliable grid analyses.   All of this will ensure a stable and reliable power supply for the community of Wachtendonk.