Demand-Side Flexibility under Alternative Electricity Market Designs: Insights from a Multi-Level Modelling Framework

The transformation of the European electricity system from centralized fossil-based generation to a decentralized renewable-based system poses challenges for the current market design with uniform national price zones. This design lacks spatially differentiated investment signals and market incentives for grid-supportive flexibility behavior. This study examines various market design options—such as bidding zone reconfigurations, capacity payments, and dynamic tariffs—and analyzes their combined effects on investment decisions, dispatch and ex-post congestion management. A multi-level electricity market model is applied to the German power system for the year 2030, incorporating market-driven investments and system operation. Results indicate that a uniform price zone leads to suboptimal investment signals and inefficient deployment of flexibility options. Capacity payments can ensure overall installed capacity levels but fail to provide regional incentives. In contrast, zonal pricing reflects structural congestion and aligns investment incentives with grid information, substantially improving flexibility deployment and reducing congestion. Overall, regional price differentiation emerges as the key driver of efficient investment and system operation, while capacity payments and dynamic tariffs only unfold additional value when combined with such locational signals.