Positive
Project advancing - milestone achieved
Medium Impact
Significant progress or notable issue
In October 2025, Heerema Marine Contractors' semi-submersible crane vessel Sleipnir installed the offshore substation topside for the East Anglia Three transmission system at the wind farm site in the southern North Sea, approximately 69 km off the Suffolk coast. The topside houses the HVDC converter equipment that will transform the collected AC power from the wind turbines to ±320 kV DC for export to shore via the subsea export cables. The offshore substation is a critical component of the East Anglia THREE OFTO transmission assets, forming part of the single offshore HVDC converter platform that connects the 1,400 MW wind farm to the onshore converter station at Bramford. The installation was reported by OffshoreWind.biz on 24 October 2025, and a subsequent March 2026 article confirmed that the offshore substation had been installed in 2025. The topside installation marks a major construction milestone for the offshore transmission system ahead of the planned commissioning in the second half of the 2020s.