A wind turbine’s lifetime is about 20 years, but when you consider that there are moving parts, you naturally expect need for repairs and maintenance. Was curious to find out how well and faultless the old turbines were, when I came across this interesting report from Bloomberg.
In Apr 2012, Vestas Wind Systems A/S (VWS) and Gamesa Corp. Tecnologica SA, two of the four biggest wind turbine manufacturers, warned clients of possible flaws in a pair of their older models. Gamesa told customers of a potential fault in a component of the G-47 660-kilowatt turbine. Vestas also told clients about a possible flaw in the “root part” of the blades for the V47 turbine of the same capacity, spokesman Andrew Hilton said.
I would have expected faults to in or in close proximity to the blades, for obvious reasons.
The component in the Gamesa turbines was designed by Vestas, Hilton said.
“This component could have faults under certain circumstances but these are not the result of a manufacturing defect,” he said in an e-mail. “Rather, this is due to a combination of wear and tear and design limitations at the time when the part was designed.”
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Hilton said Vestas has been contacting clients since September 2010 and the “vast majority” of the turbines have been scanned at no cost to customers. Less than 4 percent of the 4,200 V47 turbines in operation are affected and require repairs, he said. The turbines are typically 10 to 13 years old, and most aren’t under warranty, he said.
Gamesa offered clients a program to extend the working life of the turbines that will offset any costs arising from the possible fault, the spokeswoman with the Zamudio, Spain-based manufacturer said.
The flaw will cost customers about 20,000 euros ($26,200) per faulty component, or 27,000 euros per megawatt of installed capacity, Rosenthal said. That’s “the equivalent of more than 2 percent of total wind farm capital expenditure at today’s prices,” he wrote, making an assumption that 30 percent of the components were affected. “We consider this to be meaningful.”
