ABSTRACT
The unit mounted on top of a wind turbine tower is called the nacelle, gondola or machine cabin. Inside the nacelle there is the gearbox, generator and other mechanical and electrical components. Most large grid-connected wind turbines have conical steel towers. Smaller turbines can have a lattice tower or guyed mast. To make turbines firmly rooted in the ground, so that they will not be turned over by strong winds, turbines are mounted on foundations of reinforced concrete. If the bedrock is solid and stable they can be bolted to the rock.
