Understanding Braess’ Paradox in power grids

• Published in: Nature communications Vol. 13; no. 1; p. 5396
• Main Authors: Schäfer, Benjamin, Pesch, Thiemo, Manik, Debsankha, Gollenstede, Julian, Lin, Guosong, Beck, Hans-Peter, Witthaut, Dirk, Timme, Marc
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 14-09-2022; Nature Publishing Group; Nature Portfolio
• Subjects: 639/4077/4073/4071; 639/705/1042; 639/766/530/2801; 639/766/530/2803; Electric power; Electric power grids; Electricity distribution; Energy transition; Generators; Humanities and Social Sciences; Laboratories; multidisciplinary; Paradoxes; Planning; Power plants; Science; Science (multidisciplinary); Theoretical physics
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-32917-6

The ongoing energy transition requires power grid extensions to connect renewable generators to consumers and to transfer power among distant areas. The process of grid extension requires a large investment of resources and is supposed to make grid operation more robust. Yet, counter-intuitively, increasing the capacity of existing lines or adding new lines may also reduce the overall system performance and even promote blackouts due to Braess’ paradox. Braess’ paradox was theoretically modeled but not yet proven in realistically scaled power grids. Here, we present an experimental setup demonstrating Braess’ paradox in an AC power grid and show how it constrains ongoing large-scale grid extension projects. We present a topological theory that reveals the key mechanism and predicts Braessian grid extensions from the network structure. These results offer a theoretical method to understand and practical guidelines in support of preventing unsuitable infrastructures and the systemic planning of grid extensions.
Increasing the capacity of existing lines or adding new lines in power grids may, counterintuitively, reduce the system performance and promote blackouts. The authors propose an approach for prediction of edges that lower system performance and defining potential constrains for grid extensions.