Parsing the effects of wind and solar generation on the German electricity trade surplus

Abstract

Germany has experienced rapid growth in its renewable electricity generation capacity in the past fifteen years. This development has been accompanied by a drop in wholesale electricity prices and significant net export surpluses. This situation has given rise to discussions in policy circles concerning the drivers behind these dynamics. The paper at hand empirically analyzes historical cross-border commercial flows (CBCF) of electricity from Germany by applying a Ridge Regression model to parse the effects of the growing shares of renewable energy capacity on the commercial electricity exchange between 2012 and 2016. In case of PV, the fraction of PV generation (marginal effect of PV on export) that is exported correlates positively with the level of PV generation. However, the marginal effect of wind on export is negatively correlated with the level of wind generation. A possible explanation for this finding as it relates to wind feed-in could involve the high degree to which the grid is constrained at times of high wind penetration.