From nodal to zonal pricing: A bottom-up approach to the second-best

Congestion management schemes have taken a prominent place in current electricity market design discussions. In this paper, the implications of establishing zonal pricing in Europe are analyzed with regard to potential zonal delimitations and associated effects on total system costs. Thereby, a nodal model sets the benchmark for efficiency and provides high-resolution input data for a cluster analysis based on Ward's minimum variance method. The proposed zonal configurations are tested for sensitivity to the number of zones and structural changes in the electricity market. Furthermore, dispatch and redispatch costs are computed to assess the costs of electricity generation and transmission. The results highlight that suitable bidding zones are not bound to national borders and that losses in static efficiency resulting from the aggregation of nodes into zones are relatively small.