News, Offshore

Final wind turbines installed at 1.2-GW Hornsea 1

Ørsted has completed the installation of the last of 174 wind turbines at the world’s largest offshore wind farm, Hornsea 1, off the northeast coast of England. With the installation completed, the project will undergo a period of commissioning and will be officially inaugurated in 2020.

The component loadout took place at the Siemens Gamesa Renewable Energy factory in Hull, where the majority of blades were constructed, and the components were transported 120 km out to sea. This impressive array of 174 turbines is dotted over 407 km2 of North Sea more than 100 km from the Yorkshire coast.

The wind turbines were transported by two specialist vessels: The Bold Tern, owned by Fred Olsen Windcarrier, and DEME Group’s Sea Challenger. Both are installation vessels that jack up in the sea to provide a sturdy base for lifting. The vessels carried four turbines with each trip.

The main components include a steel tower, three turbine blades and a nacelle, which houses all generation components for the turbine. On average, it takes about 12 hours of precision working to install a turbine in full. The 7-MW turbines stand 190 m above sea level and have three 75-m-long blades.

Once complete, the site will be the world’s first offshore wind farm to be able to generate over 1 GW of electricity, enough to power well over 1 million UK homes.

“The milestone of this last turbine being installed only nine months after the first one was erected is just one small part of this record-breaking project,” said Duncan Clark, Ørsted program director for Hornsea 1. “Hornsea 1 has truly paved the way for the next generation of offshore wind farms. At the time of taking on the project, it’s scale and the technical pioneering required seemed a Herculean challenge, but a truly extraordinary effort from all those involved have managed to make this impressive feat of engineering the new norm.”

Offshore construction started in January 2018, when the first monopile foundation was installed by GeoSea’s installation vessel, Innovation. It has taken a host of contractors, suppliers and Ørsted employees to reach this landmark, with over 8,000 people having been inducted to work offshore at Hornsea 1’s site.