Tyrrhenian Link

In December 2025 the Nexans ship Nexans Aurora laid a 500 kV DC cable 2,150 metres below the surface of the Tyrrhenian Sea, the deepest installation of its kind yet recorded. The final pull-in of that western campaign was completed on 1 January 2026, and Nexans announced the record a week later.

That cable is one half of the Tyrrhenian Link, Terna’s largest subsea project. It has two branches, both meeting in Sicily at Fiumetorto, near Termini Imerese. The east branch runs about 490 km to Torre Tuscia Magazzeno, near Battipaglia in Campania. The west branch runs about 480 km to Terra Mala, on the south coast of Sardinia. Each branch carries 1,000 MW. The converter stations at the outer ends are at Eboli on the mainland and Selargius near Cagliari; those two places are the ends given above.

The east branch came first at sea. Prysmian’s ships Leonardo da Vinci and Monna Lisa laid its cables; the first of them was completed in May 2025, as Il Sole 24 Ore reported. Its deepest point is about 1,560 metres. The west branch, laid by Nexans, followed in two offshore campaigns of about 200 and 280 km.

The money is on the same scale. NS Energy puts the investment at €3.7 billion, with €1.9 billion of European Investment Bank loans approved in tranches from November 2022. Prysmian and Nexans share a cable contract worth €1.71 billion, signed in November 2021, and Siemens Energy with FATA are building the converter stations under contracts from March 2023.

The reason is geography. Sardinia and Sicily are Italy’s two largest islands, and until now each has reached the mainland on its own. SAPEI connects Sardinia to Lazio, and a new triangle through Sicily gives power more than one path between the islands and the south of the peninsula. Terna describes the whole project as the longest and deepest submarine electricity connection in the world.

The schedule has two steps. The first pole of the east branch was due to enter service in 2026, although no start of operation had been announced by September 2026, and the full link is expected in 2028. Sardinia’s older link to Tuscany is being replaced in parallel by SACOI 3, due in 2029.