What Lies Beneath Europe’s Energy Future?

EU backs subsea energy and cable links amid cost, supply, and security concerns

16 Oct 2025

Europe’s network of undersea cables is entering a new phase of expansion as investment, policy, and demand for connectivity align to strengthen the continent’s energy and digital infrastructure. Once a technical niche, subsea systems have become a strategic focus within Europe’s clean-energy and data-resilience agendas.

Recent projects mark this shift. Denmark’s Energinet has awarded NKT a €650mn contract to connect Bornholm Energy Island with Zealand, while France’s RTE and Ireland’s EirGrid are constructing the Celtic Interconnector, the first direct power link between the two countries. In the Mediterranean, several large-scale subsea initiatives led by Nexans aim to reinforce regional grids.

These efforts reflect a broader push to integrate Europe’s power and communications systems. “We’re seeing energy and data connectivity converge,” said a European Commission adviser. “Subsea systems sit at the intersection of both.”

Telecom operators are following suit. Telxius and technology groups such as Google, already active on Atlantic routes, are considering new projects linking Europe to Africa and the Americas. Spain and Portugal have become preferred landing points for cables supporting cloud and AI infrastructure.

The build-out faces persistent challenges. Analysts point to shortages of specialised vessels and skilled labour, along with lengthy environmental permitting. Some ventures have been delayed or scaled back, while regulators are tightening oversight of critical assets. Even so, public financing remains strong, including European Investment Bank support for the Spain–France interconnector and other cross-border links.

Market researchers such as Rystad Energy and GlobalData forecast double-digit growth in the subsea sector through 2035, fuelled by offshore wind and data-centre expansion. But rising costs, geopolitical tensions, and supply constraints could slow delivery.

Despite these risks, the subsea drive remains central to Europe’s competitiveness. As one industry executive observed, “The strength of Europe’s digital and energy future will depend on what we build beneath the sea.”