Integrating balancing reserves and congestion management to re-balance the German system

The current electricity market is facing new challenges as the sector moves towards a low-carbon energy system. Germany's power system is currently moving to a regional concentration of electricity supply and demand, which increases network congestion. In order to solve possible contingencies, reserve requirements are used to ensure that enough energy is available to re-balance the system. However, this measure might not be reliable in congested systems. To that extent, zones are used to address inter-zonal congestion, but intra-zonal congestion is still a problem that lacks efficient ways to solve it. We focus on quantifying the benefit of managing intra-zonal congestion using tertiary reserve capacities and of additionally splitting the reserve market into zones. The results show that the combination of balancing and congestion market is the most efficient solution since it decreases the total reserve demand quantities needed to solve possible contingencies.