A yellow steel tube stands in open water off the Danish coast with nothing on top of it.
It went in on the last day of April. It has been standing there ever since.
The top is open, and a round cover is bolted across it like a lid on a can.
That lid is not scrap. It comes off, goes back to shore and goes onto the next one.
Seventy one more tubes went in behind it.
All of them off one ship.
How a tube that size goes into the seabed
A monopile is a single steel cylinder driven into the seabed until soil friction alone holds it upright.
No concrete, no anchors, no bolted footing. The tube is the foundation.
The vessel lifts it upright over the side, guides it through a frame and lets it sink into the sand under its own weight.
A hydraulic hammer then sits on the head and drives it the rest of the way, blow by blow, until the pile refuses to move.
Noise limits shape the sequence too. The hammer starts soft so fish have time to leave before full energy goes into the steel.
Everything after that is fitting out. Boat landing, access platform, internal ladders, the steel a technician needs to climb aboard.
What sets the pace is the weather window, because the lift only happens while the sea stays flat enough.
What one of these tubes actually is
Each one runs roughly 328 feet from tip to top.
The heaviest reach about 1,650 short tons, which the developer likes to compare to a thousand small cars.
They are not made anywhere near the site. They shipped out of the heavy lift terminal at Eemshaven in the Netherlands.
Five fit aboard at a time, so the campaign ran as a shuttle rather than one delivery.
The field sits about 14 miles off the west coast of Jutland, in the Danish North Sea.
That distance is the real constraint, because a trip back for one missing part costs a full day.
The dates and the count
The first tube went down on the thirtieth of April last year, set by the crane vessel Les Alizes of Jan De Nul.
The seventy second was in place by the twenty fifth of September. Five months for the whole set.
Secondary steel followed on a different ship, the MPI Adventure of Van Oord, working out of Thyboron and finishing in early November in under six months.
The offshore substation topside, close to 2,900 short tons, had already been landed on its jacket that July.
Nothing in that sequence had to wait on a second crane vessel.
The first turbine went up on the fourth of March this year.
By the middle of July the count stood at 36 of 72, which is exactly half and leaves the rest on a year end schedule.
The covers nobody usually gets back
An open pile head is a hole in the top of a hollow steel column standing in the North Sea.
Water, salt and birds all get in, and the flange a tower bolts onto is the most sensitive surface on the structure.
The usual answer is a temporary cover that gets cut away, dropped in a skip and replaced on the next job.
Here the covers are hard, reusable and made to be lifted off, carried back and set on another foundation.
Between the last pile and the first tower there sat roughly five months of waiting, and the foundation announcement puts every one of the 72 under a cover for it.
A cover that survives one winter is not the same as a cover that survives ten.
Reuse is easy to claim and hard to check. No count of how many covers actually cycled has been published, which is the missing number behind the whole claim, and the progress update does not give it either.
What the count does not settle
Turbine size is doing most of the work in offshore wind here. Each machine is rated at 15 megawatts and carries blades about 377 feet long.
Seventy two of them come to 1,080 megawatts, which the operator puts at more than a million Danish households.
Fewer and larger machines mean fewer foundations, and fewer foundations is where a five month campaign comes from at all.
Sizing is not always uniform either, as it was not when one Dutch field went out with two diameters of foundation instead of one.
A run this clean also depends entirely on steel arriving on schedule, the same dependency that ran through the last of 95 steel piles off the Suffolk coast.
Full commissioning is set for spring next year, so the number that matters is not the halfway one but whether the second 36 go up in the same weather.
