Work on the construction of Princess Elisabeth Island, an ambitious project set to be the world's first artificial energy island combining both high-voltage direct current (HVDC) and alternating current (HVAC) systems, is advancing steadily. The project, commissioned by grid operator Elia Transmission Belgium, is managed by TM Edison, a joint venture between DEME and Jan De Nul.
Transport and installation of the caissons for the island commenced on 21 April 2025. Each caisson, weighing around 22,000 tonnes and measuring 58 metres in length, 28 metres in width, and varying between 23 to 32 metres in height depending on storm wall requirements, is being towed from Vlissingen Port in the Netherlands.
Four tugboats are being used to tow the caissons across a 53 nautical mile (approximately 98 kilometres) route via the Western Scheldt and the North Sea to the island's designated site, located around 45 kilometres off the Belgian coast. The installation of each caisson takes approximately 24 hours. Once at the site, the caisson is anchored to pre-installed foundations and filled with water, allowing it to descend in a controlled and stable manner to the seabed.
After positioning, rock armour will be placed around the caissons to safeguard them against potential summer storms. Sand will then be added to the units, and further preparations will be made for installing additional caissons.
While construction is progressing smoothly, the decision on final contracts for the island's high-voltage direct current (HVDC) infrastructure has been delayed due to rising costs. However, the island's ongoing construction and the implementation of already signed high-voltage alternating current (HVAC) contracts continue without interruption.
Once completed, Princess Elisabeth Island will be a central hub, connecting the electricity cables from wind farms in the Princess Elisabeth Zone, further strengthening Belgium’s position in renewable energy infrastructure.
