A “unique” fault in the wind turbine blade control system was responsible for the collapse of a 100m Nordex wind turbine in Ireland - the same type of turbines at Crystal Rig 1 and 1a.
The turbine collapsed on January 2 this year scattering debris more than 250 metres away and both the operators and the turbine manufacturers have been investigating the incident.
A spokesperson for Screggah wind farm in County Tyrone, said: “Nordex has concluded its interim investigation and confirmed that this was a unique fault concerning the wind turbine blade control system,”
“This has not been previously seen in the Nordex fleet, and is applicable only to turbines of a similar generation to those provided for Screggagh windfarm.
“Following identification of the failure mechanism, Nordex has immediately implemented an additional protective measure to exclude any reoccurrence of this incident.”
The remaining seven turtines at Screggah wind farm had been shut down while an investigation was carried out by Nordex and they were due to be switched back on at the weekend.
Drone Hill wind farm on Coldingham Moor also has Nordex turbines but a spokesperson for operators Greencoat UK said: “It’s not the same turbine as the ones at Drone Hill. They are N60/1300 and have been around for a lot longer. The one in Ireland was newer technology and it was a problem with the pitch of the blade.
“We did go back to Nordex after that and asked if there was anything in particular that we should be looking for but were told there wasn’t a problem.
“We inspect the Drone Hill turbines on a regular basis.”
The Screggah wind farm turbines are the same size and make as the 25 turbines at Crystal Rig 1 and Crystal Rig 1a in the Lammermuirs - Nordex N80/2500. The first 20 Crystal Rig turbines went up in 2003/4 and the additional five in 2007, four years before the turbines at County Tyrone were erected, and regular inspections have not revealed any issues.