Wind Turbines That Shake and Break Cost Their Maker Billions (1)

Wind turbines make money when they spin. But when they shake, it can cost billions.

Siemens Energy AG is struggling to contain the fallout after discovering a main piece on the frame of its wind turbine can move or twist over time, potentially damaging other critical components, according to people familiar with the matter.

Executives and board members are concerned that fixing the problem may far exceed the company’s estimate of more than €1 billion ($1.1 billion), said one of the people, who asked not to be named discussing non-public information. The magnitude, which is still being assessed and may ...