SWEDEN All visible traces of Yttre Stengrund offshore wind farm in Kalmar Sound are now gone. By the summer, just over seven kilometres of cabling will also have been removed from the sea bed.

The final turbine at Yttre Stengrund, Sweden's second oldest offshore wind farm, was decommissioned on 2 November 2015. The other four turbines had not been in operation for some time as it was not financially viable to repair or replace them.

Work on dismantling the rotors, nacelles, masts and foundations started in mid-November.

The last foundations were cut off level with the sea bed on Saturday 16 January.

Unique project
Maria Hassel is project manager for the dismantling of Yttre Stengrund, which is the first project of its kind in the world.

She explains that the first foundations, which were made of steel and concrete and had a diameter of 3.5 metres, took 29 hours to cut using a diamond wire saw.

"Because this is the first time an offshore wind farm has been dismantled we had to refine the method as we went along, and the other foundations took 13 hours to cut. Overall, the turbines weren't difficult to dismantle. We just worked in reverse order from when they were installed."

Completed by the summer
Maria Hassel is pleased with the project, which was slightly delayed due to bad weather.

"By the summer, probably August, seven kilometres of cabling will have been removed from the sea bed. The project will then be complete."

Timelapse video of THE dismantling of one of the rotors

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