Red Eléctrica, the subsidiary of Redeia responsible for electricity transmission and system operation in Spain, has begun construction of the onshore section of the new underground and submarine interconnection between Spain and France via the Bay of Biscay. The 13-kilometre underground route in Bizkaia, running from the new Gatika converter station to the coastline, avoids urban centres and primarily uses existing forest roads and tracks.
This phase involves excavating two trenches approximately 1.5 meters deep, traversing the municipalities of Gatika, Maruri-Jatabe, and Lemoiz. Upon completion, the surrounding environment will be fully restored, with only small inspection chambers visible every 500 meters.
Construction of the Gatika converter station is already underway, and horizontal directional drilling near Lemoiz for the marine landing point has also commenced. Cable installation is scheduled to begin within a year and continue through 2027.
Throughout the process, Red Eléctrica is working closely with local authorities to minimise disruptions to public use and maintain transparent communication with communities affected by the works.
A Sustainable, Consensus-Driven Design
The interconnection project was designed through an open, participatory process to ensure the best technical, social, and environmental outcomes. Road and river crossings, as well as the marine landing, will be executed using horizontal directional drilling to prevent any impact on natural areas or human activity. The Gatika converter station was strategically located to maximise distance from population centres and reduce effects on local flora, and will be visually screened with vegetation for improved landscape integration.
The project also includes key environmental and social enhancements, such as the dismantling of two 10-kilometre overhead transmission lines between Gatika and Lemoiz, which will significantly reduce visual impact. Additionally, it will stimulate economic activity and job creation in Bizkaia and the Basque Country, with numerous contracts awarded to local companies.
The interconnection will connect the Spanish and French electricity systems through two 400 kV links, running fully underground and underwater from Gatika (Spain) to Cubnezais, near Bordeaux (France). From the coast of Lemoiz, a 300-kilometre high-voltage direct current (HVDC) submarine cable will run to the French shore, avoiding the Capbreton Canyon, followed by an 80-kilometre underground route to the new converter station in Cubnezais.
A Project of Common Interest for Europe
This strategic project, jointly developed by Red Eléctrica and French operator RTE through the 50-50 joint venture Inelfe, has been recognised as a Project of Common Interest by the European Commission and Parliament. It is co-financed by the European Climate, Infrastructure and Environment Executive Agency (CINEA), as part of EU funding programs for energy, transport, and climate action.
Once completed, the new interconnection will double the electricity exchange capacity between Spain and France to 5,000 MW. This will enhance grid security and supply quality, facilitate greater integration of renewable energy, and improve system efficiency, ultimately benefiting consumers across both countries. The initiative is also key to meeting European energy interconnection targets and achieving strategic energy autonomy for the EU.
