Policy implications of spatially differentiated renewable energy promotion: A multi-level scenario analysis of onshore wind auctioning in Germany

Auctions have been introduced in many countries as a useful alternative for renewable energy support. However, they often lead to a high concentration of renewable energy power plants at productive sites, at the expense of other, less favorable sites. This paper studies the impact of alternative renewable energy auction schemes on the promotion of renewable energy in Germany, using a novel multi-level approach—analyzing auctioning on the national, north/south, and federal states level, respectively. First, using a GIS tool, the onshore wind potential is studied at a high regional and temporal resolution. The results of this analysis show a considerable untapped onshore wind potential in the southern federal states of Germany. Second, an onshore wind power auction model is developed by using a system dynamics approach. Finally, the policy support payments are compared for different auction designs by using an electricity market simulation model. The findings suggest that more bidders from the southern federal states could win in the regional auctions. Detailed spatial analysis reveals a trade-off between balanced diversity of bidders and the average auction price. We conclude that regional auctioning can indeed lead to significant support payment savings, and should thus be considered in renewable energy support policy design.