Spanish grid operator begins laying 13 km cross-border transmission cable

en.Wedoany.com Reported - On October 29, Spanish grid operator Red Eléctrica began laying the onshore underground cable for the Spain-France Biscay Bay cross-border power interconnection project. This construction section is 13 km long, extending from the Gatika converter station in Spain to the coast at Lemoiz, where it connects with the submarine transmission cable. Overall construction progress on the cross-border interconnection project has reached 70%; once completed, the power exchange capacity between the two countries will increase from 2,800 MW to 5,000 MW.

The high-voltage direct current cable being laid has a diameter of 13 cm. The route consists of 4 power cables, with fiber-optic cables for facility operation laid in parallel alongside them. Red Eléctrica previously completed the land-sea connection section at Lemoiz, including 4 horizontal directional drilling ducts each more than 1 km long, with the drilling exits located in the seabed area about 500 meters from the coastline.

The submarine cable works have completed two construction phases along the Biscay coast. In August, the cable-laying vessel "Victoria" of Denmark's NKT completed the installation of the first 65 km of cable; in September, "Prysmian Monna Lisa" completed the second phase of 50 km of submarine cable laying. With this, all submarine cable laying along the Biscay coast has been completed. Workers are now carrying out cable covering and protection in rocky seabed areas and burial operations in sandy seabed areas.

Civil works at the supporting Gatika converter station have been completed, and the project has now entered the electromechanical equipment installation phase. The subsequent plan calls for offshore cable laying off the coast of Gipuzkoa from November 2026 to February 2027, with all submarine cable laying in French waters to be completed in summer 2027. Red Eléctrica also plans to dismantle two existing overhead transmission lines, each 10 km long, between Gatika and Lemoiz.

The cross-border power interconnection project is jointly developed by Red Eléctrica and French transmission operator RTE through the joint venture Inelfe. It has been listed as a Project of Common Interest of the European Union and has received funding support from the European Climate, Infrastructure and Environment Executive Agency and the European Investment Bank.