The Impact of Redispatch on Grid and Storage Expansion Planning in the German Energy System

In light of the necessity for a cost-effective transition to a new energy system, it has become increasingly important to consider the integration of redispatch measures as a potential option in long-term grid planning. This could help to avoid the need for significant expansion of the grid and storage facilities. In this paper, we present a novel method for the consecutive optimization of the sector-coupled electricity system of the year 2035 at bidding zone level, as well as on a 300 bus model of the German extra high and high voltage grid. Therefore, redispatch can be explicitly co-optimized in conjunction with grid and storage expansion. The results demonstrate that redispatch measures can markedly reduce the necessity for grid and storage expansion, ranging from 76% to 78% in the German grid. By employing only 21% of the optimal annual redispatch volume, 77% of the potential investment cost savings can already be captured.