Impact of German wind generation forecasts on net transfer capacities

Because of its localization and its variability, wind generation can rapidly change the pattern of physical electrical flows between AC interconnected countries and adds more uncertainty in power system operation. Therefore, the increasing installed wind generation capacities may hamper the commercial net transfer capacities made available between countries. Through a statistical analysis using generalized additive models (GAM) on data from March 2008 to June 2010, this paper looks at the impact of the day-ahead hourly forecasts of German wind generation on the day-ahead net transfer capacities (NTCs) from Germany to France. Results are five-fold. First, the analysis shows that wind generation forecasts have a significant impact on the NTC, by explaining around 14% of the deviance. Second, this effect is negative: more the wind blows, less NTC are available. Third, German wind generation areas have different impacts. The paper shows that 50Hz and Amprion have the greatest influence. Fourth, the German consumption forecast impacts the NTC, but to a lower extent than wind generation forecasts, while the French consumption exhibits no significant effect. Last, the modeling is still incomplete and several improvements are proposed.