The undeniable fact that the wind is not always blowing as expected is making wind power a largely unreliable energy source. The other big problem is the unreliability of the technology of wind power stations. This problem has hit the Spanish wind power provider Iberdrola massively, after ball bearings of wind power stations proved not to work—when the news about that got out, Siemens Energy, the Gamesa subsidiary that provides Iberdrola with the systems, saw its shares lose 37% on the stock market on Tuesday, June 27. They regained 6.7% on Wednesday, but lost 2% again on Thursday.
Bloomberg reported expert estimates that the repair of some 1,000 wind power stations of the new generation might require more than the €1 billion that the Siemens Energy management claims, but at least €1.6 billion. Siemens could be faced with even more trouble if the older generations of systems also showed need of urgent repair.
