Ships to install offshore wind generators

The European Union has plans to expand electric production by wind turbines up to 20 percent of total production in 2020, Spain being one of the leading countries in installed capacity of such generators located onshore.

Recently they have begun to install wind turbines at sea in areas up to 200 miles offshore and at not excessive depths, outstanding this kind of parks in North Sea countries. These "off-shore" generators solve some of the problems arising onshore, as noise, visual aesthetics, environmental opposition, and they get too a better use of wind power, which is greater at sea than onshore, and also allow for larger power / sizes, with better economic performance.

However, the installation of wind turbines offshore is more complex and expensive than the land one, so that procedures are being introduced of increased sophistication and technically advanced in order to reduce these costs. Particularly, they have designed and built specifically for this service, vessels of various types, which seems will have high demand in the coming years.

The shipyard "La Naval" from Sestao (Spain), of CNN group, is making inroads into this market niche, which fits into his philosophy of building special ships to allow them compete with the ubiquitous Far Eastern shipyards.

 At the recent Leadership Bilbao conference, that took place on April 21 at the Maritime Museum Ría de Bilbao,  the Euskadi(Basque Country)' president Patxi López announced, during the opening ceremony, that, thanks to the efforts of his Industry and Economics councillors, guarantees from CESCE (credit insurance)have been secured as required to complete the financing of a special vessel, for installing offshore wind generators, to be built by "La Naval", as soon as they sign the contract. Although I only have a rough knowledge of this ship's particulars, I have no information that can published, so I will only limit myself to quote some features of these vessels type.

The off-shore wind turbine, which drives the electric generator is mounted on the upper end of a tubular support, which in turn is attached to a steel jacket anchored at the sea bed. They have designed two types of vessels for these installation works: 

1) vessels for installation of jackets at the sea bed

2) vessels for installation of turbines with tubular supports, on the jackets (2 variants)

The descriptions and sketches of these ship types, as shown below,  are taken from the magazine "Ports and Dredging" Spring 2010 / E174.

Type 1: not-propelled barge (click to enlarge)

This design corresponds to a not-propelled barge that carries up four Jackets that are lowered to the sea bed together with their interlocking piles, which are secured by means of a hydraulic hammer. The transfer of the jackets from the vessel up to their locations on the sea bed is achieved through two mobile gantries running on skates on the barge deck. 

Type 2: Jack-up vessel (variant 1)

This design is a self-propelled vessel equipped with DP2 dynamic positioning, with capacity to carry up to six 6 MW wind turbines with tubular supports, and transfer them from the vessel up to the jackets at the sea and from the pier to the vessel. The ship is equipped with four hydraulic driven "legs", which are hydraulically lowered  to rest on the seabed and then can raise the deck to make it a stationary work platform. It is a similar system to that used in jack-up oil drilling platforms. This is the ship type that is expected to be built by "La Naval" from Sestao.

Type 3: Ship (option 3)

This design is a self-propelled vessel equipped with DP2 dynamic positioning, with capacity to carry up to six 5 MW wind turbines with tubular supports, and transfer from the vessel to the jackets at the sea and from the pier to the ship. The vessel works as floating, with position and movements control through DP2 and ballast tanks, with a patented motion-compensated manipulator/handling system.

I hope that this contract from "La Naval" will materialize soon and later on I should be able to post a more specific data and specification. And I hope too that this can be the start of a series of this kind of vessels  which afford for the next activity in Sestao shipyard.