Pre-check is made under the assumption that all turbines are operating normally and the pre-construction energy yield assessment was correct. The remaining source of uncertainties are the wind conditions observed in the particular period.

The information that the wind conditions were below or above average can be roughly determined by GEO-NET Wind Index based on reanalysis data and long term measurements.

Given the turbine power curves and the historic production, the Production Index Anomaly graphic will present if the wind farm performs according to its potential.