Failed anemometer
Understanding what the WindESCo failed anemometer issue check is for
What is the purpose of the turbine issue check?
- The anemometer on a given turbine appears to have failed and is providing unreliable wind speed and direction measurements.
- If the anemometer has failed, the turbine may be incorrectly cutting-in, cutting-out, or yawing non-optimally.
What does this look like?
- The failed anemometer can be identified in several ways, but a clear one is through the yaw misalignment estimate that was previously consistent, but is now deviating from typical behavior
- For WindESCo, this has typically been indicative of a failure or impending failure
![](https://www.windesco.com/hs-fs/hubfs/image-png-3.png?width=585&height=221&name=image-png-3.png)
- A failed anemometer can also sometimes be identified by comparing rated power among peers and identifying discrepancies.
- In this case the anemometer (and therefore NTF) was biased low for 7 turbines
![](https://lh5.googleusercontent.com/FyCjt0twnip4diANsS0za3tZ_ZiNersOzrdo6rDIceguHEJ3xRJs4tP8UFtd1MJx557ywAICEQSvioliWg9UZeKNs3s9fZ2mYDevcattZHzpyuQ3l4NlQinnLiMKJq3GBZbK-7aPnN5Z89-Nd0-6_PQ)
How can you tell the issue is corrected?
- This issue is corrected when the anemometer is replaced. In that case there would be a consistent yaw misalignment (or none) identified, and the median power would be consistent among turbines.
- For the 7 impacted turbines (second example), the anemometers were corrected and the NTF was recalibrated.
- This corrected the performance at cutout wind speeds associated to a $40,000/yr benefit for the site