Swissgrid AG has successfully completed the renewal of its 220 kV air-insulated substation (AIS) in Sursee, Canton Lucerne, Switzerland. Originally built in 1981, the substation had reached the end of its service life, prompting a comprehensive modernization to meet current technological and ecological standards.

The project, completed at the same location, was led by PFIFFNER Systems AG as the turnkey project and engineering lead. Haveco AG managed installation, while MGC Moser-Glaser AG, ALPHA Elektrotechnik AG, and PFIFFNER Instrument Transformers contributed to design and equipment supply.

Key upgrades included the dismantling of outdated infrastructure, installation of new AIS apparatus, retrofit of a busbar longitudinal separation, renewal of the earthing system, and improved protection barriers. The entire process, including civil works, was completed within nine months, adhering to strict safety, quality, and cost guidelines.

Despite challenging weather conditions and operating within an active substation, the project remained on schedule, with key milestones met in June and October 2024. The upgraded facility is now operational and integrated into Swissgrid's network.

This project marks a significant step in Swissgrid's efforts to modernize Switzerland's electrical grid. The experience gained is expected to contribute to future high-voltage infrastructure projects.