In mid-September, the last caisson for 2025 was installed at the Princess Elisabeth Island in the Belgian North Sea, an important step in the construction of the world’s first energy island. This year’s offshore campaign has now concluded, involving a team of more than 300 people and a fleet of 15 specialized vessels, including jack-up vessels, supply vessels, and tugboats.

The caissons, massive concrete structures weighing up to 22,000 tons, form the outer walls of the future island, located 45 km off the Belgian coast.

Once completed, the island will connect offshore wind farms and may also serve as an energy hub for international interconnectors to the Belgian electricity grid. Developed by Elia Transmission Belgium, the project is being built by TM Edison, a consortium including DEME and Jan De Nul.

Preparations for the next phase are underway, with offshore activities set to resume in spring 2026, weather permitting.