Like any other piece of major equipment in the power industry, wind turbines represent a large investment for the companies that rely on them to generate both electricity and revenue. Unlike gas turbines or boilers in coal-fired power plants, however, wind turbines present some unique challenges.
Keeping a wind turbine's gearbox properly lubricated is important in extending the life of a wind turbine.
The type of oil that is used in a turbine's gearbox – and for all other parts of a wind turbine – is usually designated by the original equipment manufacturer for the units, with a main difference being whether the oil is a synthetic or mineral.
The gearbox is not the only part of the turbine that requires lubrication, however. The generator bearings and blade bearings also require lubrication, and there are lubrication points on the blades. Wind tower blades have bearings that will essentially feather the blade so operators can optimize the blade angle to match wind speed. The main shaft bearing and yaw and pitch drives also require lubrication. The turbines also use a hydraulic system that provides a braking mechanism for a unit, but can also be used for hydraulic pitch control on the blades.
With all these different parts requiring lubrication, multiple products could be required in order to maintain a single turbine.
One of the complications with maintenance is that there is a tremendous variety of turbines on the market, says Prior. With models produced globally, maintenance needs are specific to the individual vendor.
Make sure you receive a maintenance checklist from the manufacturer so you can account for scheduled servicing, recommends Graham. This is particularly crucial because replacement parts like filters and grease are highly specialized and often must be ordered.
Despite mechanical variations, turbine maintenance typically involves:
Larger turbines have higher annual maintenance costs because their design is more intricate.