A malfunctioning sensor led to the the collapse of a GE Vernova turbine at Enefit Green’s in-construction 75MW Akmene wind farm in Lithuania, according to the developer.
One of the wind turbines malfunctioned with the tower bending and nacelle falling to the ground. Nobody was injured in the accident, which happened in March.
Enefit Green said in a statement that “detailed root cause analysis has led to the conclusion that a malfunctioning sensor sent incorrect information to the turbine controller which led to an excessive load on the tower structure and resulted in the collapse of the turbine”.
“Following identification of the failure mechanism, General Electric has identified and is implementing additional protective measures to prevent any recurrence of this specific or similar incident in the future”, Enefit added.
According to the accident investigation commission, the accident of the completed installation of the wind power plant on occurred suddenly, because the load during several rotation cycles of the rotor was greatly increased and the mechanical resistance of the steel tower sheets was exceeded.
When the steel wall buckled in two places (11 and 72 m high), the stable balance of the tower was damaged, so the tower began to tilt and finally the top with the rotor fell to the ground, into the nearby forest.
The segments between the folded areas remained almost intact, the highest tower segments were partially folded when they fell, the connections between the segments were damaged, the upper technological equipment was damaged and the cables, ladders, engineering networks inside the tower were damaged.
No cracks in the foundation concrete or damage to the anchor bolts were visually detected.
The Akmene wind farm is one of three Enefit Green’s wind farms under construction in Lithuania.
It consists of 14 wind turbines supplied by General Electric.
The wind farm will produce an estimated 258 gigawatt-hours of green electricity annually.
The construction of Akmene wind farm started in February 2022. Partial electricity production started this year.