Cable Installed 3,000 Meters Deep Sets New World Record

French technology company Nexans just installed a power cable 3,000 meters below the ocean surface off the coast of Sicily, setting a new world record for underwater cable installation. That's roughly the height of seven Empire State Buildings stacked on top of each other, all underwater.

The 525 kilovolt cable carries electricity using a technology called high-voltage direct current, which loses less energy over long distances than traditional power lines. Nexans completed the installation and testing on March 10, 2026, in waters west of Sicily, Italy.

This marks the second time in three months that Nexans has broken its own record. In December 2025, the company installed a cable at 2,150 meters deep as part of the Tyrrhenian Link project, one of Italy's largest electrical infrastructure upgrades.

The company didn't just go deep. They tested the cable at 30% above standard industry requirements to make sure it can handle extreme underwater conditions without failing.

The Ripple Effect

Deeper cable installations open up new possibilities for connecting renewable energy sources across vast ocean distances. Islands and coastal communities that once relied on diesel generators or expensive overhead lines can now tap into cleaner power grids.

The Mediterranean Sea poses unique challenges with its deep trenches and busy shipping routes. Proving that cables can work reliably at these depths means engineers can route power connections through the most direct paths rather than taking longer, shallower routes that waste energy.

Each record-breaking installation also trains teams and refines techniques that make the next project easier and more affordable. The lessons learned off Sicily's coast will help connect offshore wind farms, link island nations to continental grids, and move clean energy where it's needed most.

The technology matters beyond Europe too. Countries planning major renewable energy projects across deep waters now have proof that the infrastructure can handle it.

Nexans proved that the future of clean energy can reach even the deepest parts of our planet.