How does a private photovoltaic boom cause bottlenecks in the electricity grid?

The Austrian transmission system operator Austrian Power Grid (APG) had to intervene in the domestic energy supply for 25 days in July 2023 alone. This comes from broadcasting. This prevents overloading of the power grid. And in the whole year, the so-called retransmission procedure was necessary for 130 days. These are controlled interventions in the power grid using thermal and hydraulic power plants.

Interventions in the power supply are necessary because the electricity grid is very vulnerable. Above all, the expansion of renewable generation now exceeds the capacity of the electricity infrastructure, warned APG Technical Director Gerhard Christener, again calling for more speed in the expansion of the electricity grid. Regional electricity surpluses fed back into the transmission grid in an uncontrolled manner would make predictions more difficult and would have to be removed from the system at great cost.

20 million euros costs in July alone

According to the APG, these interventions also cause high costs. Total costs of €19.7 million were incurred in July alone. Ultimately, electricity customers will have to pay these costs. “Having a strong electricity grid with sufficient capacity would significantly reduce the need for redistribution and reduce costs,” said Thomas Carral, APG Chief Financial Officer.

In total, 97% of electricity consumption in July was covered by renewable energies. Of the total 3,867 GWh of renewable electricity produced in Austria, hydropower accounted for the largest share with 3,052 GWh.