Wind Energy – HKZ
34 out of the 140 monopile foundations were installed at the 1.5 GW Hollandse Kust Zuid wind farm offshore the Netherlands in the first installation campaign, falling short of the target set for 2021, Vattenfall said.

This summer, on the 5th of July, the offshore construction on the 1.5 GW Hollandse Kust Zuid wind farm with 140 Siemens Gamesa SG 11.0-200 DD wind turbines officially started. Over the next year and a half, Hollandse Kust Zuid, owned by Vattenfall and BASF will be built off the Dutch coast.
Just before construction started, Ian Bremner returned as project director for Vattenfall’s flagship offshore wind project– after having already worked on HKZ back in 2018. In a latest press release by Vattenfall, Bremner looks back at the first construction campaign, and provides a peek into next year’s activities.
The foundations and secondary steel components are installed on site by the installation vessel Seaway Strashnov.
“We had a challenging start, due to some unexpected technical difficulties on the foundation installation vessel,” Ian explains. “However, once those were resolved and we were up and running, things went really well, and the pace of installation was meeting our expectations. Unfortunately, further technical difficulties interrupted the momentum and we never quite recovered the earlier performance. The delays pushed the works further and further into adverse weather periods to the point where it was no longer viable to continue. This translated into us falling short of our foundation installation target for 2021.”
“However, there is flexibility in the start date of the second foundation installation campaign, and that allows the project to recover the installation shortfall from the first campaign.”
The second campaign should start at the beginning of March, with the installation of the remaining 106 monopiles. Next spring, the first cables and turbines will also be installed. The turbine strings will need to be connected to the offshore substations ready for energization and delivery of first power. The team is using the coming winter period to prepare for this new phase.