ScottishPower Renewables pulls off record 1,793-metre duct landfall at $5.30 billion East Anglia TWO windfarm

A subsea drilling operation off the Suffolk coast has delivered the world's longest continuous single sections of extruded polyethylene ducts, according to ScottishPower Renewables, which has completed the work at its USD 5.30 billion East Anglia TWO offshore windfarm.

Longest continuous ducts ever installed mark landfall success

The two ducts, each just under 1,800 metres long and 800mm in diameter, will house the high-voltage export cables carrying power from the 960MW windfarm to shore, and together form the largest electricity transmission landfall of its kind in the UK when length and diameter are combined.

For scale, the company points out that the duct length matches the historic Royal Mile in Edinburgh, running from Edinburgh Castle to Holyrood Palace, or the stretch of the River Thames between the London Eye and the Tate Modern.

The installation relied on Horizontal Directional Drilling (HDD), a method that bores beneath the Suffolk coastline and seabed without digging up beaches, dunes, cliffs or coastal habitats, thereby limiting disruption to the environment and sensitive landscapes. Rigs worked onshore and offshore at the same time to complete the bore.

Three times longer than previous East Anglia landfalls

Ross Ovens, Managing Director for Offshore at ScottishPower Renewables, said finishing the HDD — three times the length of those on the company's other East Anglia projects, was a huge achievement and a major milestone as construction advances on its third windfarm in the region.

He stressed that the priority is always to deliver clean energy projects and their benefits responsibly and sensitively, mindful of the environment and the people around them. While landfall works are among the most technically challenging parts of building an offshore wind farm,

he credited precision planning and strong partnership with principal contractor OCU Group and duct manufacturer Pipelife for breaking UK and world records in the process. The HDD works sit within the wider East Anglia TWO civil engineering programme, delivered by OCU Group with support from its subsidiary Peter McCormack & Sons. The contract is supporting more than 80 jobs during construction.

Mike McNulty, HDD Director at OCU Group, called the delivery of a landfall HDD at this scale an exceptional engineering achievement requiring meticulous planning, technical expertise and close collaboration. Installing two 1,800-metre, 800mm diameter PE pipes, each in a single continuous section, was, he said, testament to the skill and commitment of everyone involved, and demonstrates what specialist engineering, strong partnerships and a shared commitment can achieve in delivering major energy infrastructure responsibly.

Made in Norway as one unwelded length, towed to Thorpeness

The record ducts were produced by Pipelife at its Stathelle facility in Norway. Martin Myhre, Project Manager at Pipelife Norway, said that at 1,793 metres this was the longest pipe the company has ever manufactured, describing it as a significant milestone.

Continuous extrusion allowed the pipe to be made in one uninterrupted length without welding, removing welded joints and producing a more robust and reliable solution for such a demanding application. The pipes were then towed from Norway to Thorpeness in England, a journey Myhre called extraordinary. He noted that a project of this scale demands close collaboration and careful planning across the entire supply chain.

Cable installation and operation timeline ahead

Attention now turns to the wider project schedule. The first of East Anglia TWO's export cables is expected to be installed in summer 2027, with commercial operation targeted for late 2028.

The windfarm will sit in the southern North Sea, around 33km from the Suffolk coast at its nearest point off Southwold and 37km from Lowestoft. Once operational at up to 960MW, the project will be capable of powering the equivalent of almost one million homes with clean electricity generated in the UK. To date, it has injected more than USD 1.99 billion into the UK supply chain.