The current rules for classifying anemometers used to measure wind speed need amending, according to consultancy Deutsche WindGuard.
The regulations are covered by IEC 61400-12-1 which allows for the classification of anemometers in labs.
But lab tests do not take into account the operating conditions, especially with regards to air pressure and temperature, Deutsche WindGuard said.
The consultancy said that new research has found that ambient conditions in the lab have a “much higher influence on the behaviour of sensors than previously assumed”.
Deutsche WindGuard Wind Tunnel Services managing director Dieter Westermann said: “As we have extensive experience with the classification of anemometers, we have been aware for some time that the assumptions of the IEC with regards to temperature and air pressure influence were simplified.
“However, there was no possibility to provide experimental evidence as there was no wind tunnel to recreate these conditions.”
The company therefore built a special wind tunnel for anemometer classification that can simulate temperatures ranging from -20° to +40°C and air pressure from 600 hectopascals (hPa) to 1100 hPa.
“This enables us to reproduce ambient conditions of wind energy sites from the Sahara desert to mountains in the Andes in our lab here in Varel,” Westermann said.
WindGuard is working with anemometer manufacturers on further research in this areas.
Image: Pixabay
Wind speed tests ‘need upgrade’
By EBS