Two wind power prognosis criteria and regulating power costs

The objective of the present work is to investigate the consequences of the choice of criterion in short-term wind power prognosis. This is done by investigating the consequences of choice of objective function in relation to the estimation of the power curve that is applied in the prognoses. Basically, the choice is between focusing on predicting the energy content of the wind and focusing on the cost of buying regulating power to compensate for the prognosis errors. It will be shown that it can be expected that the two power curves thus estimated will differ, and that therefore also the hourly wind power production predicted will differ. In turn this will influence the operation and economics of the system. The consequences of this are illustrated by application to the integration of wind power in the Danish parts of the Nordpool area, using recent data. Using a regression analysis the prices of regulating power will be estimated. Then the two mentioned power curves may be estimated using wind speed production from the numerical weather prediction model from the Danish Meteorological Institute and the corresponding short term prognoses of wind power will be elaborated. From wind power production measurement the errors may be calculated. Combining this information it is possible to find the consequences of inconsequent use of prognosis criterion, i.e., using one criterion in estimating the power curve and another in assessing the quality of the prognosis.