by Jerome a Paris
Thu Sep 6th, 2012 at 05:27:46 AM EST
On Monday, I was invited to the christening in Bremerhaven of the biggest special purpose vessel to be built for the offshore wind industry to date, the Innovation:
The vessel is owned by a joint venture of Hochtief, the German construction group, and DEME, the Belgian marine works group, and will be put to work first by Areva on Globaltech 1, one of the big wind farms in construction in Germany now (and one that was project financed) and later on Northwind, a Belgian offshore wind farm (also project financed, in this case with the involvement of my company).
The godmother of the vessel is Mrs van Rompuy, as befits a truly pan-European industrial development (the vessel was assembled in Poland, the owners are Belgian and German, with respective large French and Spanish shareholders, the first client is French and the base of operations is in Germany).
The ceremony took place in Bremerhaven, a city being transformed by the offshore wind industry, and with the perfect backdrop of ongoing construction work for several offshore wind farms. See some more pictures below - including from the boat itself, as the guests were allowed to visit large bits of the vessel.
You can see the ship and its huge crane standing alongside the tripod foundations that have been manufactured for the offshore wind turbines and are now waiting to be shipped out. The vessel will be able to carry 3 of these tripods, plus the 3 smaller piles for each tripod used to "nail" these into the subsea floor (you can see some of these piles already on board the vessel in the pictures below). In this case, there will be 'post-piling', ie the tripods are lowered on the sea floor first and then the piles are driven through into the seabed; it is also possible to do 'pre-piling' - the small piles re driven into the ground first, and then the foundation is lowered onto them and positioned on them like a big lego game.
One of the features of the vessel is its large crane, allowing to carry the loads required at sea (the owners say there will be able to install turbines and associated equipment of up to 10 MW). An interesting feature of this vessel is that the crane is built around one of the legs of the ship (more on these in a second), allowing it to have a lot more freedom of movement, in particular its overall angle of rotation.
The legs are an essential part of the vessel, as they allow it to "jack up", ie to stand on these legs as they are lowered down on the seafloor, and be perfectly stable for construction work even if the sea is not calm. An important parameter of these legs is how big they are, which drives the sea depth at which the vessel can work - in this case the vessel can work up to depths of 50m, meaning that it will be able to install turbines and foundations in most of the North Sea. The vessel is also self-propelled, meaning that it can go back and froth from construction site to harbor on its own, without need for tug boats (a number of existing jack up vessels are simple barges which need to be dragged around).
We were allowed to walk on the helipad at the top of the structure, and to enjoy the view - as can be seen above, Bremerhaven is a city fully dedicated to the wind industry, with multiple (onshore) wind turbines installed nearby - in the case above, it's one of the testing sites for new turbines, where some of the first 5MW turbines were installed to be tested onshore, and where the jacket foundation concept was test in full scale.
A nearby barge carried some jacket foundations for the NordSeeOst project being built by RWE, alongside the tripods for the Globaltech and Borkum West projects