TSO-DSO interface for Net Zero: the German case of 50Hertz and its DSO neighbour TEN Thüringer Energienetz*

As Germany advances towards its energy transition goals, the imperative to expand and restructure its power grid infrastructure becomes increasingly evident. The current infrastructure lacks the capacity to meet future demands, highlighting the pressing need for action. Escalating challenges related to system security and grid reliability underscore the critical importance of fostering close coordination between Distribution System Operators (DSOs) and Transmission System Operators (TSOs). Collaboration is particularly crucial in control areas such as for instance 50Hertz’s in north-eastern Germany, where efficient management of energy fluctuations is essential for the successful transition to high renewable energy usage. Regulatory strategies aimed at facilitating this transition must prioritize a strong collaboration between DSOs and TSOs necessary for stability, optimizing operations, and securing the network. This article is intended to illustrate how a regulatory framework for such TSO-DSO cooperation in north-eastern and eastern Germany for congestion management could be necessary, in accordance with the next grid development plans. Regulatory gaps associated with such interface will be identified and policy recommendations derived from them will address the challenges and opportunities linked to congestion management and the utilization of smart grid technologies.