Specifically, the only known damage caused to wind turbines due to a tremor was in 1986, during the North Palm Springs earthquake. The incident resulted to a small number of turbines suffering damage, which were primarily consisting of buckling of some of the segmented tower walls which resulted in tilting of the structures, but no overturning and collapse of the towers was reported.
Today's turbines are different that the past's, and from the 1986's earthquake no catastrophic loss of a wind turbine has been recorded, in any earthquake.
In addition, the closest incident where seismic activity was reported to impact a wind turbine was when the ground surrounding a wind turbine foundation liquefied during the 2011 Tōhoku earthquake resulting in minor tilt of the foundation.
DNV GL reported that infrastructure, as substations, seems to be more fragile. Thus, it is of a great importance that wind turbines continue to be properly designed for earthquakes to continue good performance as wind energy become more widespread.
Moreover, the recent strong magnitude 6.4 and 7.1 seismic events near Ridgecrest, California, which were felt in the wind power plant regions of Southern California, remind us that earthquakes induced loads must also be considered for wind turbines.
The shaking in Tehachapi and Palms Springs was relatively low, with a peak ground acceleration of 0.03 g and 0.016 g, respectively. With such low ground accelerations, no damage is expected to the wind power plant regions and none has been reported to date.