The Importance Of Oil Cleanliness / [4 u; M6 [: y* I# N sOil cleanliness has a huge impact on the lifetime of the bearings and gearboxes in wind turbines. % O7 T; T! [$ K$ g- i: r- R7 m! gOil contamination can be reduced considerably by the use of fine filtration, doubling the lifetime of bearings and gearboxes (source: Life Extension Factor, Noria Corporation). 1