Heerema Installs Substation at Inch Cape Offshore Wind Farm

Siemens Energy Offshore Transformer Module being installed by Heerema Marine Contractors’ Sleipnir (Credit: Inch Cape Offshore )

The Inch Cape Offshore Wind Farm offshore jacket foundation and substation platform have been installed at the North Sea site of the 1.1 GW Scottish project.

The Siemens Energy Offshore Transformer Module (OTM) and its 68-meter jacket foundation are now in position 21 kilometers from the Angus coast having been installed by Heerema Marine Contractors (HMC) semi-submersible crane vessel Sleipnir.

The compact 2700-tonne platform comprises two circuits with two transformers and reactors, making it Siemens Energy’s first ever double OTM.

The modular fabrication, which enables offshore wind platforms to be smaller and lighter than conventional alternating current designs, has now been in use for 10 years.

A team of more than 250 at the Smulders yard in Newcastle, fitted out and assembled both the OTM and its jacket foundation over the past approximately 18 months. Around 80 local U.K. sub-contractors supported the project with work that included lifting, scaffolding, engineering and coating.

Owned in a 50-50 equal joint venture by ESB and Red Rock Renewables, Inch Cape, is the largest offshore wind farm now in construction in Scotland. Once complete it will generate almost 5 terawatt hours (TWh) of energy each year or enough to power half the homes in Scotland.

“This has been an impressive team effort by Siemens Energy, Smulders, Heerema and the myriad smaller contractors who contributed to ensuring the safe and efficient fabrication and installation of these major Inch Cape components,” said John Hill, Inch Cape Project Director.

Inch Cape Offshore Wind Farm is owned by Inch Cape Offshore Wind, an equal joint venture between ESB and Red Rock Renewables.

Construction of the project’s onshore substation and landfall works in Cockenzie, East Lothian, are well advanced and the next key offshore activity will be the installation of the first of two export cables, scheduled for late summer this year.

First power is expected in late-2026 and with commercial operation date in 2027.