And yet it sits on a barge about to be floated 30km downriver and then 75km out to sea, where it will be lifted on top of a 3,500-tonne steel foundation.

It is a monumental undertaking but one that is key if Germany is to achieve its ambition of having 25GW of wind power in the North Sea by 2030.

The yellow box at marine contractor Heerema’s fabrication yard in Zwijndrecht, South Holland, is the 800MW DolWin Alpha, the first of a series of giant offshore converter stations destined for German waters.