The spinner anemometer was invented in 2004, as a result of many years of research in performance and wind measurements of wind turbines. The idea was to measure the wind in the center of the rotor, with as little distortion of the measurement as possible. Traditionally wind speed and wind direction has been measured at the back of the wind turbine nacelle, causing a lot of flow distortion from the rotor blades. This drawback is totally eliminated with the spinner anemometer.
The spinner anemometer has been tested with two generations of prototypes, partly in wind tunnels, partly in free field tests on the ground or on wind turbines. A preproduction model has also been tested on commercial turbines, giving experience from both flat and complex terrain. The results showed that the spinner anemometer concept worked perfectly according to the idea.