First steel cut marks start of HVAC works for Belgian offshore energy hub

SCHIEDAM (NL) – BRUSSELS (BE) | A new milestone has been reached in the development of Belgium’s offshore energy hub. Today, the construction of the high-voltage alternating current (HVAC) infrastructure officially began with a first steel cut ceremony at the HSM Offshore Energy yard in Schiedam (the Netherlands). The HVAC modules – which include high-voltage substations and a facility module – will be directly installed onto the Princess Elisabeth offshore energy hub. Located 45 km off the Belgian coast, the artificial island will serve as a key connection point for transporting at least 2.1 GW of offshore wind energy generated in the Princess Elisabeth Zone to the mainland.

A strategic project for Belgium’s electric future

The HVAC substations will house essential components such as power transformers and gas-insulated switchgear (GIS), so forming the backbone of the island’s AC transmission infrastructure. The modules are being built by HSI Pemac, a Belgian-Dutch consortium comprising HSM Offshore Energy, Smulders, and Iv-Offshore & Energy. The consortium was awarded the engineering, procurement, construction, installation and commissioning (EPCIC) contract by Elia, Belgium’s national transmission system operator, which is part of Elia Group. Engineering works - including the layout and a detailed 3D model - are being carried out at Iv’s offices in Papendrecht (NL). The prefabrication process is taking place at Smulders’ Belgian facilities and HSM’s Schiedam yard, with the final assembly occurring in Schiedam and Vlissingen.

Full HVAC scope underway

The broader HVAC infrastructure for the island includes 330 km of 220 kV HVAC subsea cables, divided into two 165 km packages. These cables will connect the island’s AC infrastructure to Belgium’s mainland grid.

"The start of the construction of the island’s HVAC infrastructure shows that the project is progressing steadily— even as we adapt its next phase in line with new market realities. The Belgian government’s recent decision to develop an alternative approach for the HVDC components will ensure that we can maintain the strategic ambition of the project in a more cost-effective way. Along with our partners and the authorities, Elia remains fully committed to delivering Belgium’s offshore energy hub that will strengthen our country’s future electricity supply and support Europe’s energy transition.”

— Frédéric Dunon, CEO of Elia Transmission Belgium

" This first steel cut is more than the start of fabrication — it is a tangible sign that one of the most strategic energy projects in Europe is moving from plan to reality. We are proud to help bring this essential infrastructure to life, so supporting the growth of offshore wind and the strengthening of European energy security.”

— Hans Leerdam, Commercial Director at HSM Offshore Energy

A revised approach for the project’s next phase

On 6 June 2025, the Belgian federal government announced that an alternative approach for the next phase of the Princess Elisabeth offshore energy hub would be developed. While aligned with the project’s original goals, the updated approach will be aimed at reducing the costs involved by responding to the sharp global increase in the price of high-voltage direct current (HVDC) technology and related offshore services. The ambitions for this phase remain unchanged: to expand the offshore wind capacity in Belgium’s second offshore wind zone and to realise a second interconnector with the United Kingdom. Elia will work closely with the government, the Commission for Electricity and Gas Regulation (CREG) and other stakeholders to assess all of the options and assess what the most efficient and cost-effective approach will be.

About the Princess Elisabeth offshore energy hub

Princess Elisabeth offshore energy hub will be the world’s first artificial energy island. As part of its first phase of operation, it will collect electricity from two new wind farms located in Belgium’s second offshore wind zone and so enable the integration of this energy into the country’s onshore grid. The island will strengthen Belgium’s long-term electricity supply and accelerate the integration of renewable energy into the European grid.