Energy

Wind

Aeolian knowledge

The wind and land roughness

The speed of the wind depends, as well as on atmospheric parameters, on land conformation. The rougher the land, the more sudden inclination variations it has, the more forests, buildings and mountains, the more obstacles the wind will meet, the more its speed will be reduced.
In order to define the conformation of a land, four types of roughness have been detected:

roughness 0: the soil is flat, such as the sea, the beach and the snow
roughness 1: open soil with non-farmed land, low vegetation and airports
roughness 2: agricultural areas with few buildings and few trees
roughness 3: rough soil with many variations in soil inclination, forests and villages.

Usually the best position for an aerogenerator is on a land with a low roughness degree.