Offshore substation installed at Inch Cape

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

The compact 2700-t 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 Wallsend, Newcastle, fitted out and assembled both the OTM and its jacket foundation over the past approximately 18 months. Around 80 local UK sub-contractors supported the project with work that included lifting, scaffolding, engineering, and coating.

John Hill, Inch Cape Project Director, said: “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.”

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 TWh of energy each year or enough to power half the homes in Scotland.

Paul Lennon, Head of Offshore Wind, Hydrogen and Long-Term Storage at ESB, commented: “After successfully reaching financial close earlier this year, this is yet another significant milestone for the Inch Cape project. For us at ESB, along with our partners Red Rock Renewables and the whole project team, getting to this stage has required key expertise and this has been demonstrated by all of those involved in making this happen.

“I would particularly like to commend Siemens Energy, Smulders, and all other project partners today as we mark this important step. Inch Cape will make a significant contribution to the UK’s climate goals, and we are getting ever closer to that happening.”

Xiaomeng Chen, Red Rock Renewables CEO, added: “The successful installation of the offshore substation marks a major milestone for Inch Cape and a proud moment for everyone involved. It’s fantastic to see the project making such strong progress and I’d like to thank our partners and all those who contributed to its delivery.”

Construction of the project’s onshore substation and landfall works in Cockenzie, East Lothian, are well advanced and the next 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.

For more news and technical articles from the global renewable industry, read the latest issue of Energy Global magazine.

Energy Global's Summer 2025 issue

Dive into the latest renewable energy insights in the Summer issue of Energy Global, out now! This edition features a guest comment from Change Rebellion on the role real change management can play in the global energy sector before a regional report, which looks at energy trends and transformations across the Americas. Other key topics are also explored, including offshore support vessels, floating wind, weather analysis, and battery storage. Contributors include Ørsted, CRC Evans, Miros, Solcast, and more, so don’t miss out!

Read the article online at: https://www.energyglobal.com/wind/04082025/offshore-substation-installed-at-inch-cape/