Installation of turbines in progress

The installation of turbines on the foundations is now in full progress at the construction site at Horns Rev. By May 23, a total of seven complete turbines were installed, including rotor.

A2SEA, a sub-supplier of Vestas', now has both crane vessels in operation. The crew onboard the Ocean Hanne continues the installation of tower sections on to the foundations whereas the crew on Ocean Ady installs the nacelles.

If the weather allows it both vessels and Vestas' crew are in operation 24 hours a day throughout the week.

Towers and nacelles are pre-installed at the Port of Esbjerg to minimize the offshore installation work.

Onboard the Ocean Ady, a tailor-made rack holds two nacelles.

Once the crane vessel is positioned next to the already installed tower, the nacelle, with two pre-installed blades, is lifted on to the tower and is bolted to the top flange. Then the third blade is installed by means of tailor-made lifting equipment. The lifting process is critical and requires good weather conditions.

The crane vessel remains next to the tower during final installation and final tightening of the bolts.

Pre-assembly of nacelle at the Port of Esbjerg

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First nacelle loaded on to the crane vessel

Nacelle almost in position on turbine tower

Preparations for lifting of third blade

Third blade installed (photo: Jan Vium)

Complete turbine

Status on foundations

The driving of foundation piles and the installation of transition pieces are on to schedule. By May 23, 28 piles have been driven of transition pieces have been mounted on 26 of these. Erosion layers have been established at 22 of the turbines.

Buzzard, the pile driving vessel, at sea

Cable pulling within the wind farm

Cable pulling has been initiated within the wind farm. The first two inter-turbine cables have been pulled along the seabed and will be trenched soon in 1-2 meters' depth.

The cables between Eltra's substation and the individual groups of turbines, the so-called radial cables, are expected to be pulled within the coming fortnight. The same vessel, the "H.P. Lading" that pulled Eltra's submarine cable ashore from the substation, trenches these cables.

Noise measurements

During the construction of the wind farm a number of environmental aspects are monitored closely. One of these aspects is the underwater noise during pile driving. Hence, the sound pressure is measured during pile driving.

Technicians from Tech-wise's department for noise and vibrations measure the noise in various depths and at various distances from the pile driving scene. The measurements are currently being analysed.

Pile driving

The work of pulling Eltra's submarine cable from the substation and ashore is on schedule. Transmission of power is expected to begin on July 1, 2002. The mentioned submarine cable now has to be trenched and to be connected to the land cable in the cable transition station, which is located approx. 1 km from the coast at Oksby. The land cable from Oksby and to the substation at Karlsgårde has already been pulled.

Right now, the submarine cable is being connected to the offshore substation and a number of finishing and testing jobs are being carried out at the offshore substation.

Eltra's substation

Owner coordination

The Horns Rev project is a big project with a huge number of activities, numerous business partners, great dependence on good weather conditions and, last but not least, a very tight time schedule. This requires very close coordination between all parties involved. For this Elsam has gathered a team of coordinators at the Port of Esbjerg who manage the coordination of traffic, diving activities and safety aspects related to the Horns Rev construction site.

Tech-wise A/S, one of Elsam's subsidiaries, has been entrusted with handl­ing all the practical work as Owner's engineers. Before this project, Tech-wise A/S has managed engineering, coordination and supervision jobs in connection with numerous other projects.

Traffic coordination

The traffic coordination team supervises all project-related sea traffic to and from the Horns Rev construction site. Traffic coordination is manned 12 hours a day, seven days a week, and receives information from all sailing units such as position, activity and number of persons on the site.

Diving coordination

As part of the safety measures for the Horns Rev project, Elsam has established and operates a pressure chamber. The chamber is located on board the vessel "Gitte Iversen" which is at anchor just outside the construction site area. The vessel crew consists of two men and a person to operate the pressure chamber.

Safety coordination

The Owner is in charge of the coordination of safety on the construction site. This includes the site at the Port of Esbjerg and the offshore site. The coordination is carried out according to the authorities' rules and regulations; including requirements made by Arbejdstilsynet (The National Working Environment Authority) and Søfartsstyrelsen (The Danish Maritime Authority).

Traffic coordination is manned 12 hours a day, seven days a week

The vessel "Gitte Iversen" with pressure chamber before departure from the Port of Esbjerg.

Web cam transmissions from the Horns Rev site

You can now follow the live transmissions from the web-cam at Horns Rev.

The web cam has been installed on Eltra's substation and shows turbine no. 91 (see also below map). 

The camera will be moved to a better location soon. This means the camera will be able to move freely and therefore also cover the areas of the wind farm where there is most activity.

The transmission is made by radio link to Elsam's power station in Esbjerg from where the pictures are transferred to Elsam's Internet server.

Numbering of turbines

All turbines in the wind farm have their own number. The sketch shows the principle of number­ing. In the top horizontal row, from the left to the right, the numbering starts with turbine no. 01, turbine no. 11, then turbine no. 21 and so on and so forth. In the second horizontal row from the top, turbines no. 02, 12, 22 etc. are found. The black square marks Eltra's substation.

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