NKT completes high-voltage power cable replacement for Swedish hydropower plant

Hydropower accounts for nearly half of the electricity supply in Sweden making it a cornerstone in the country’s transition to renewable energy. The Letsi hydropower plant in Northern Sweden is one of the oldest of its kind in the region and with more than five decades of operation it was time to renovate the Letsi hydropower plant in 2019. NKT was awarded the turnkey replacement project for the power cable system by Vattenfall and has completed the project of designing, producing and installing the new 400 kV AC single-core XLPE power cable system with a power rating of 486 MW.

- It has been a pleasure to continue our collaboration with Vattenfall to prepare the Letsi plant to produce renewable energy for more decades to come. This project once again shows our position as a key player in ensuring the transition to renewable energy with a strong technology base and a very experienced organization supporting our clients in connecting a greener world, says Axel Barnekow-Widmark, Executive Vice President and Head of Service and Installation in NKT.

The execution of the replacement project was done in several stages from draining the oil filled legacy power cables and removing the old terminations, pulling the underground power cable and connecting it to a new transformer. The replacement work came with some major challenges due to the nature of the physical environment in Northern Sweden, but NKT managed to complete the project successfully.

- We knew that the cabling in our underground installations would be a complex task that required careful preparation. Throughout the project, NKT has been extremely professional, taking every precaution to ensure the quality of their delivery. We have been very satisfied with NKT’s delivery and their open and responsive approach to unpredicted challenges, says Robert Falk, Project Manager at Vattenfall.

The new power cable system was commissioned in June 2021 and is now in operation generating renewable energy for the Swedish power grid.