Two significant milestones for the HKZ offshore grid connection project

Hollandse Kust (zuid) Alpha, our client TenneT’s high voltage connection for the Netherlands’ offshore wind farms HKZ I and II is ready for use. The installation and energisation of the offshore grid connection has been completed. Wind farm developer Vattenfall can now connect the wind turbines to the high voltage grid. On top of that, the HKZ Beta topside was successfully installed.

Grid Readiness

TenneT received the ‘Grid Readiness’ certification from DNV GL for HKZ Alpha on Tuesday 22 March. This means that this offshore grid connection fully complies with the conditions set out by the Offshore Wind Energy Development Framework.

Marco Kuijpers, TenneT’s Director of Large Projects Offshore said:

“With the energisation of the Hollandse Kust (zuid) Alpha connection, the offshore grid that TenneT is building in the North Sea is starting to take shape. Hollandse Kust (zuid) Alpha is the first connection of an offshore wind farm to the Maasvlakte, with a capacity of 700 MW. The energization of Hollandse Kust (zuid) Beta later this year will add another 700 MW from wind farms Hollandse Kust (zuid) III and IV.”

Made in the UAE

Petrofac is responsible for the complete Engineering, Procurement, Construction and offshore installation of two High Voltage Alternating Current (HVAC) transformer stations – Alpha and Beta, both designed and built in the UAE.

The Alpha topside was installed on its jacket, about 20 kilometres off the coast of The Hague, in December 2021. Sister topside Beta left its fabrication yard in Dubai in February 2022 and sailed to the North Sea, where it arrived last week.

After completion of all preparatory work, the Allseas multipurpose platform installation and removal vessel Pioneering Spirit lifted and positioned the Beta topside on its jacket, the foundation of the platform.

Sami Iskander, Petrofac Group Chief Executive said :

“The safe installation of the Beta topside is a significant milestone in the delivery of this important energy transition project. Everyone involved should be proud of this achievement.”

Marco Kuijpers added:

“Wind energy plays a crucial role in the energy transition, also in industry, and I am proud that TenneT, together with our partners, can contribute to a sustainable future in this way.”

HKZ is the first subsidy-free wind farm area in the world. When fully operational in 2023, it will generate an amount of renewably energy that is equivalent to the annual consumption of more than two million households.