A stable power grid is essential for a reliable and sustainable energy system. Photo credit: Markus Breig / KIT |
A sustainable energy supply requires the expansion of the power grids. However, new lines can also make networks not more stable as expected, but more unstable. The phenomenon is called Braess paradox. This has now been simulated for the first time in detail for power grids, demonstrated on a larger scale and developed a forecasting instrument by an international team in which researchers from the Karlsruhe Institute of Technology (KIT) are also involved. It is intended to support network operators in making decisions. The researchers report in the journal Nature Communications.
The sustainable transformation of the energy system requires an expansion of the networks in order to integrate renewable sources and to transport electricity over long distances. This expansion requires large investments and aims to make the networks more stable. By upgrading existing lines or adding new lines, it can also happen that the network does not become more stable, but more unstable and there are power outages. “We then speak of the Braess paradox. This means that an additional option instead of improvement leads to a deterioration in the overall situation,” says Dr. Benjamin Schäfer, head of the research group Data-driven Analysis of Complex Systems (DRACOS) at the Institute for Automation and Applied Computer Science at KIT.
The phenomenon is named after the German mathematician Dietrich Braess, who first discussed it for road networks: under certain conditions, the construction of a new road can extend the travel time for all road users. This effect was observed in traffic systems and discussed for biological systems, but has so far only been theoretically forecast for power grids and presented on a very small scale.