Hornslet Wind Turbine Collapse
Encyclopedia
The Hornslet Wind Turbine Collapse was a spectacular collapse of a wind turbine, which took place on February 22, 2008. It is one of only a few structural collapses that have been captured on film.
The collapsed wind turbine was the first and northernmost turbine of Hyacintvej Wind Park, which consists of 5 similar wind turbines, arranged in a row pointing in south-southeastly direction.
was called, which checked and repaired the brake of the wind turbine on the morning of February 22, 2008. The main gear made of the turbine made also some unusual noise at the last routine inspection. A sophisticated endoscopic inspection of the gear was planned, but as result of its high cost, it was not done until that day.
After repair and several checks of the brake, the turbine was restarted in order to bring it back into normal operation. At this time the wind was very strong. The airbrakes at the tip of the blades were turned out, as they are used to control the speed of the turbine before it reached operational speed. After its generator was synchronized to the grid a noise from the nacelle occurred. Immediately it was tried to stop the turbine manually.
A large crash sound as a possible result of gear failure occurred and the turbine began to oscillate very strongly. Then the rotor stopped suddenly, but started turning again. The rotor did not turn very fast, but it was now impossible to control the rotation of the wind turbine.
The tower was evacuated immediately. As the airbrakes of the turbine have broken off and as a strong wind blew, the turbine started rotating faster and faster and reached soon a speed much greater than it was designed for. The service personnel contacted the police, which established a security zone of 400 metres around the turbine. 2.5 hours after, at about 3:20 p.m, the blades were torn off. One of the blades hit the top of the tower, which bent again wind direction and fell down. The base of the tower remained standing. The debris of the turbine flew 200 – 500 metres wide. No people were hurt.
The collapse was filmed from a nearby farmhouse. The film was shown on several TV stations and is available online. The turbine was until June 2008 replaced by a new wind turbine of the same type.
Description of Wind Turbine
The collapsed wind turbine was a Nordtank NKT 600-180/43 with a maximum generation capacity of 600 kW situated at Hornslet, Danemark at 56°20′42.97"N 10°10′13.03"E. It was operated by Syddjurs and inaugurated on December 23, 1996. The rotor of this turbine, which carried in the Danish wind turbine register the designation 570715000000021503, had a diametre of 43 metres. It was mounted on a free-standing steel-tube tower 44.5 metres above ground.The collapsed wind turbine was the first and northernmost turbine of Hyacintvej Wind Park, which consists of 5 similar wind turbines, arranged in a row pointing in south-southeastly direction.
Accident
After a malfunction of the brake, which was worn, a service team from VestasVestas
Vestas Wind Systems A/S is a Danish manufacturer, seller, installer, and servicer of wind turbines. It is the largest in the world, but due to very rapid growth of its competitors, its market share decreased from 28% in 2007 to 12.5% in 2009...
was called, which checked and repaired the brake of the wind turbine on the morning of February 22, 2008. The main gear made of the turbine made also some unusual noise at the last routine inspection. A sophisticated endoscopic inspection of the gear was planned, but as result of its high cost, it was not done until that day.
After repair and several checks of the brake, the turbine was restarted in order to bring it back into normal operation. At this time the wind was very strong. The airbrakes at the tip of the blades were turned out, as they are used to control the speed of the turbine before it reached operational speed. After its generator was synchronized to the grid a noise from the nacelle occurred. Immediately it was tried to stop the turbine manually.
A large crash sound as a possible result of gear failure occurred and the turbine began to oscillate very strongly. Then the rotor stopped suddenly, but started turning again. The rotor did not turn very fast, but it was now impossible to control the rotation of the wind turbine.
The tower was evacuated immediately. As the airbrakes of the turbine have broken off and as a strong wind blew, the turbine started rotating faster and faster and reached soon a speed much greater than it was designed for. The service personnel contacted the police, which established a security zone of 400 metres around the turbine. 2.5 hours after, at about 3:20 p.m, the blades were torn off. One of the blades hit the top of the tower, which bent again wind direction and fell down. The base of the tower remained standing. The debris of the turbine flew 200 – 500 metres wide. No people were hurt.
The collapse was filmed from a nearby farmhouse. The film was shown on several TV stations and is available online. The turbine was until June 2008 replaced by a new wind turbine of the same type.
External links
- http://ronslog.typepad.com/ronslog/2008/02/wind-energy.html
- http://www.youtube.com/watch?v=CqEccgR0q-o - Video
- http://www.windaction.org/documents/21858
- http://193.88.185.141/Graphics/Energi_i_tal_og_kort/energidata_kort/stamdataregister_vindmoeller/AnlaegProdTilNettet20080616.xls - List of wind turbines in Denmark