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Wind turbine: "fell over" in the night
Of course that wind turbine might just have fallen down accidentally in the 50mph winds - after all it was designed to withstand 120mph winds. Rumour has it some bolts from the base are missing - the company which built and maintains it is not commenting.
A saboteur would not need to actually remove any of the bolts at the base; just loosening them would be sufficient to cause excessive wear followed by a collapse.
That said, the most recent turbine designs have been adapted to prevent vandism and the bolts are actually inside the tube which can only be accessed via a hatch which is kept locked. However these turbines are still vulnerable to hunters shooting at birds sitting on the blades and accidentally hitting the blade itself. This knocks a small hole in the blade and the resulting imbalance wrecks the machine's gearbox next time there is a heavy wind.
Whenever this happens the locals do not seem particularly concerned.