Horns Rev

Horns Rev (also known as Horns Reef) is a shallow area (glacial and sea deposits of sand) in the eastern North Sea, about 15 km / 10 miles off the westernmost point of Denmark, Blåvands Huk. It contains the first large scale offshore wind farm in the world, Horns Rev 1 (160 MW from 2002), and is four times larger than the previous largest offshore wind farm in the world, the Middelgrunden at 40MW.

At Horns Rev the Danish Energy company Elsam (now DONG Energy) built the first offshore wind farm in the North Sea. A total of 80 Vestas V80-2.0 MW units, capable of producing 160 MW, were installed by the Danish offshore wind farms services provider A2SEA in 2002 with the last turbine coming into operation on 11 December 2002. Since 2005, the wind farm has been owned and operated by Vattenfall. It cost DKK2bn.

Turbines are laid out as an oblique rectangle of 5 km x 3.8 km (8 horizontal and 10 vertical rows). The distance between turbines is 560 m in both directions.

The main method of transport to the first wind park is an adapted Eurocopter EC-135 helicopter. Hoisting the workers to and from a small platform on each turbine allows access to the park regardless of sea conditions which would otherwise prevent sailing in the area for a large part of the year.

In April 2012, most of the Danish Folketing (parliament) agreed to send out tenders in 2013 for a 400 MW wind farm at Horns Rev called Horns Rev 3, and a 600 MW at Kriegers Flak in the Baltic Sea. This, along with the 400 MW Anholt Offshore Wind Farm, is expected to raise wind power in Denmark above the current 28% of annual electricity production.