Off Suffolk’s coast a single steel pile went in at 1,800 metric tons and 275 feet tall, and the vessel that set it drove all 95 into the seabed
A crane the height of a forty story building swings a steel cylinder wider than a two lane road out over open water.
Below it, the North Sea is gray and moving.
The cylinder weighs as much as five fully loaded jumbo jets.
The monopiles stand 220 to 275 feet tall and up to 35 feet wide, dimensions that place them at the outer edge of what any jack up crane has lifted anywhere to date.
It has to land inside a few feet of its marked spot on the seabed, 43 miles off the Suffolk coast.
This has now happened ninety five times in a row.
What finally made that possible starts with the machine doing the lifting.
Why building a bigger jack up vessel was the real bottleneck
A jack up vessel does not float while it works. It drives four or six steel legs down to the seabed and pushes its own hull clear of the waves, turning a boat into a fixed working platform the instant the swell would otherwise make precision lifting impossible.
That stability is what lets a crew set a steel pile within inches rather than feet. The problem was scale. Monopiles for East Anglia Three run between 1,200 and 1,800 metric tons, thick enough that their diameter reaches up to 35 feet.
No jack up crane in Europe had ever lifted one this heavy. So the vessel contracted for the job, Seaway7’s Seaway Ventus, went into the yard first, its lifting gear rebuilt for this new weight class before a single foundation touched water.
What it actually looks like to seat one of these in the seabed
Picture the scene the way the crew saw it in April 2025, on the day the first pile went down. Standing 275 feet tall, 35 feet in diameter and weighing 1,800 metric tons, the monopile became the largest pile installed to date from a jack up vessel in Europe, taller than a 25 story building, driven into a seabed nobody could see.
ScottishPower Renewables chief executive Charlie Jordan called the moment “a real wow moment,” adding “we’re talking an incredible 1800 tonnes of steel, safely and securely lifted and then precisely placed in the exact spot.”
That first pile became the template for the next ninety four. Each one then received a transition piece, the collar that bridges the raw steel tube to the tower above it, supplied by Windar Renovables and completed in September.
The number that confirms this actually happened, not just a plan
By mid August, the record was no longer a single headline lift but a finished job. The owners, ScottishPower Renewables and Masdar, confirmed on 17 August that all 95 monopiles and their transition pieces were in place, with turbine installation underway.
The piles came from two fabrication lines rather than one. Haizea Wind Group and the Navantia-Windar consortium built them, shipping finished sections to the Suffolk coast for the Ventus to lift straight off the transport barge.
Weight and height were only part of it. The monopiles stand 220 to 275 feet tall and up to 35 feet wide, dimensions that place them at the outer edge of what any jack up crane has lifted anywhere to date.
Where a record like this still has a limit
None of this makes the foundations the finish line. A steel tube in the seabed produces no electricity on its own, and the harder work now sits above the waterline.
Turbine installation has already passed the halfway point, with each tower carrying blades longer than anything installed in UK waters before. The 377 foot blades will sit on turbines with a tip height of 860 feet and a rotor diameter of 755 feet, a different kind of lift entirely, closer in risk profile to balancing a wing section than planting a pile.
A monopile record also does not travel to every seabed. Deeper water or softer sediment elsewhere in the North Sea has already pushed some developers toward floating foundations instead, a shift this desk has tracked near a disputed ceiling in Dutch waters.
What the finished foundations mean for the grid still waiting
Once all 95 turbines are up and spinning, the arithmetic turns blunt. The 17 August milestone confirmed the turbines will generate a total of 1400MW of clean energy, enough to power the equivalent of more than 1.3 million homes, a single project roughly doubling the output of many national wind fleets from a decade ago.
That scale depends on more than steel. The same engineering pressure now pushing artificial intelligence into siting work, the subject of a recent model built to map wind flow around hillsides and towers, is starting to shape where future monopile records get attempted.
Bigger piles only make sense where the wind resource justifies the lift. For now, the Suffolk seabed holds ninety five confirmed positions, each one a steel tube driven to a measured depth and signed off before the crane moved on.
East Anglia Three is expected to become fully operational by the end of 2026, the record foundations already finished, the taller work still rising above them one blade at a time.
Hugo is an engineer with strong technical expertise. Multilingual from an early age, his writing combines technical clarity with a strong interest in science and energy.
