Parts of a Wind Turbine

A modern wind turbine is a few dozen major components working together to turn wind into grid electricity. This guide labels each part, explains what it does, and links to the service that maintains it.

The rotor: blades and hub

The three blades and the hub together form the rotor. The blades are aerofoils that convert wind into rotation; the hub connects them to the drivetrain and houses the pitch bearings. Blades are the most exposed and most expensive-to-replace component, so blade repair and leading-edge protection are among the most common services.

Inside the nacelle: drivetrain

The nacelle is the housing on top of the tower. Inside sits the drivetrain: the main shaft and main bearing, the gearbox (on geared turbines) that steps up rotational speed, and the generator that produces electricity. Direct-drive turbines omit the gearbox and use a large generator instead. Wear in these components drives most major repairs, covered by gearbox, generator and drivetrain repair and gearbox repair.

Pitch, yaw and control

The pitch system rotates each blade to control how much energy it captures and to feather the blades in high wind; the yaw system rotates the whole nacelle to face the wind. Both are maintained under pitch and yaw systems. The controller and power converter manage the generator's output and grid connection, serviced under electrical and control systems.

Tower and foundation

The tower raises the rotor to heights where the wind is stronger and steadier, and the foundation anchors the whole structure against enormous overturning loads. Bolt tensioning, grout repair, coatings and safety systems fall under tower, foundation and nacelle services.

Keeping it all turning

Every one of these components is on a maintenance schedule, and every one eventually needs inspection, scheduled maintenance and, for the big items, crane-assisted exchange. If you are weighing up when to intervene, our blog on the Australian fleet leaving warranty walks through the planning.