General Electric is investigating a blade break at the 200.6MW Prairie Breeze Wind Energy Center in Nebraska, another in a series of structural failures since 2013 and the second involving an Invenergy project.
The latest incident occurred on 21 April at 1300 and involved the facility’s 51st unit which had already been commissioned and was in operation. A section of the blade fell to the ground.
No one was injured, according to Invenergy, which is among GE’s largest and most loyal wind turbine customers in North America.
It is working with GE to determine the cause of the incident. The wind farm will utilize 118 model 1.7-100 GE turbines. There was no immediate comment from GE.
Invenergy says commissioning of remaining units is proceeding and full commercial operation is scheduled in May.
Last November, commissioning of Invenergy’s 94MW Orangeville wind farm in New York State was disrupted by a turbine blade breakage involving 1.6-100 units.
In December, GE said it determined that the root cause of the Orangeville blade break and another at a Michigan wind farm owned by utility DTE Energy was a “spar cap manufacturing anomaly.”
Lightning was the apparent cause of a blade failure earlier this month at the 200MW Wildcat 1 wind farm in Indiana owned by E.ON Climate and Renewables North America.
Spar caps are load carrying structural members usually made of carbon fibre that help support the blade’s outer aerodynamic shell. Carbon fibre allows higher stiffness and lower density to enable a thinner, lighter blade profile.
A DTE official told Recharge that the defective blades were manufactured by a GE supplier in Brazil. It was not immediately known if the defective Nebraska blade came from there.
Unlike major rivals Siemens and Vestas, GE does not produce its own wind turbine blades, relying instead on a global supplier network.
GE has not made public the cost of replacing several dozen blades. All affected units have been under warranty.
Despite ongoing blade issues, there is no sign of customer defections. The wind market perceives GE as having a problem with a supplier, not its turbines.
North America is by far the most important wind turbine market for GE, where it has been the leading supplier in the past 13 years.