Compensation for systematic forecast error

The systematic forecasting error is a difference between the average measured power and the average forecasted power. Usually, this error is site dependent. If sufficient data in the range between zero and nominal power is available, the forecasts can be compensated for the systematic error. To this end a linear regression is applied between the data of each wind turbine or wind farm, yielding the slope and the offset to be applied on the forecasted power in order to obtain the correct average (that is: equal to the measured average when applied to the same data set).