How Europe Plans to Link Its Offshore Power Future

RTE, TenneT, and Terna lead Europe’s HVDC push toward unified offshore grids and a connected renewable era

24 Oct 2025

Europe’s push to knit its renewable-energy assets into a single offshore grid is quickening. The technology at its core, high-voltage direct current (HVDC), was once a niche pursuit of engineers. It is now central to Europe’s plan to link wind farms, energy islands and interconnectors across seas and borders.

At the centre of this effort is InterOPERA, a Horizon Europe-backed research consortium led by RTE of France, TenneT of the Netherlands and Germany, and Italy’s Terna. Its mission is to prove that HVDC systems from rival manufacturers can operate together. The group has published studies showing how shared technical standards could make such interoperability feasible. That would remove one of the industry’s biggest bottlenecks: incompatible systems that slow projects and lock countries into particular suppliers.

Manufacturers such as Siemens Energy and Hitachi Energy are joining the push, testing open-technology designs and shared specifications. Collaboration of this sort is a shift for a sector long marked by proprietary control. A more unified approach could accelerate grid expansion, cut costs and reduce Europe’s dependence on any single firm.

InterOPERA’s work runs until 2027, after which commercial roll-outs could follow. The technology could underpin the next wave of offshore “energy islands” and shared grid hubs that move renewable power from where it is generated, often the windy North Sea, to where it is needed most.

Still, obstacles remain. Balancing cooperation with intellectual-property protection will test the limits of openness. Regulators must also define who is responsible when systems from different makers meet beneath the waves. Yet the direction is clear. What began as a technical experiment is turning into a political and industrial project to build a truly connected European power network.