Siemens Gamesa Renewable Energy (SGRE) and Castrol have completed a joint engineering project which demonstrated the oil change intervals for yaw gear units can be extended from 5 years to 10 years, reducing maintenance costs reducing maintenance costs significantly.
Yaw gear units enable wind turbines to turn so they face directly into the wind. A wind turbine can have up to 8 yaw-gear units where the oil typically needs changing every 5 years. This is a difficult and time consuming operation taking more than 3 hours for each turbine. Since no electricity is generated when a turbine is shut down for maintenance, this downtime can prove to be extremely costly.
Research carried out by Castrol and SGRE suggest a 10-year oil-change interval for yaw gear units is practical. Castrol and SGRE’s tests demonstrated that Optigear Synthetic X 320 can last for seven years or more in the main turbine gearbox, conditions which are far more challenging than those found in yaw-gear units. The conclusion SGRE reached based on these tests is that a 10-year oil-change interval for yaw-gear box oil changes is possible. The corresponding reduction in maintenance costs and overall downtime translates to a significant reduction in the levelised cost of energy for SGRE wind turbines.