France and Ireland Connected by 575km Undersea Power Cable

France and Ireland just got a whole lot closer, thanks to a 575-kilometer underwater cable that's about to change how Europe shares clean energy.

The company Nexans has successfully completed the first major cable installation for the Celtic Interconnector, linking Brittany, France with East Cork, Ireland. Using the vessel Calypso, crews laid sections of high-voltage cable across the ocean floor, building a power highway between continental Europe and the Irish electrical grid.

The numbers behind this engineering feat are impressive. The cable system uses 320 kV high-voltage direct current technology and can transmit 700 megawatts of electricity. That's enough power to supply 450,000 households with energy.

The project combines cutting-edge manufacturing from across Europe. Norwegian facilities produced the submarine cable's specialized XLPE insulation, which protects the system underwater. Meanwhile, plants in Belgium and Switzerland created the land-based cable sections that connect to existing power infrastructure.

The Ripple Effect

This connection transforms how two countries manage their energy needs. When wind farms in Ireland generate excess renewable power, that electricity can now flow to France. When French nuclear or solar facilities have surplus capacity, Ireland benefits.

The partnership between grid operators RTE in France and EirGrid in Ireland demonstrates how countries can work together on climate solutions. Instead of each nation building excess capacity to handle peak demand, they can now share resources efficiently.

The Celtic Interconnector strengthens energy security for both countries. Power outages become less likely when grids can draw from multiple sources across borders. Renewable energy integration becomes easier because intermittent wind and solar power can be balanced across a larger network.

This infrastructure also reduces Europe's dependence on fossil fuel imports. As both nations push toward carbon neutrality, cross-border connections like this one make renewable energy more practical and reliable.

The project represents years of planning, international cooperation, and technical innovation. The successful completion of cable laying in France follows earlier work in Ireland, bringing this ambitious vision closer to reality.

Europe's integrated electricity system just got stronger, proving that collaboration can power a cleaner future for everyone.