A method for estimating remaining useful life of components of an operational wind turbine

A method and a system for estimating remaining components life of an operational wind turbine from actual wind turbine operation conditions after it was commissioned, using a data acquisition module configured to measure real historical data of said operational wind turbine, and an additional state detection unit configured to identify historical states of operation. The method comprises extracting historical data from the data acquisition module at time intervals, identify operational states of the wind turbine, validate the identified operational states and identify uncertain data that do not match. Next, simulate a turbine model for each operational state identified and wind condition thereof at each time interval, and calculate a fatigue equivalent load for each operational state and wind condition.