Given the increasing requirements for the transmission grids in the new energy landscape, a high degree of security of electricity supply can only be maintained with considerable effort on the part of the transmission system operators (TSOs) – in Germany and everywhere else. The four German TSOs and TSCNET shareholders 50Hertz, Amprion, TenneT, and TransnetBW are as aware of this just as their European colleagues. What they also recognise is that grid extension enhances security of supply, reduces the need for TSO interventions and thus also the costs for congestion management, mainly caused by redispatch. This is also confirmed by independent sources, in this case, the statistics on German supply security in 2019 by the Forum Network Technology / Network Operation (FNN) within the German Association for Electrical Engineering, Electronics, and Information Technology (VDE – Verband der Elektrotechnik, Elektronik und Informationstechnik) – one of Europe’s largest technical-scientific associations with corporate and institutional members.
According to VDE FNN, the power supply in Germany has not only become more sustainable and climate-friendly but has also remained exceptionally reliable – thanks above all to the round-the-clock commitment of the grid operators. The new 2019 disruption and availability statistics prove that the high expenditure in grid operation is successful: Calculated over the entire country, an electricity customer was without electricity for only 12.0 minutes on average in 2019 (2018: 13.3 minutes). This means that every household was supplied with more than 99.997%. To achieve this, TSOs make an enormous effort. They operate the grids within the permissible limits of frequency, voltage, and load although operational requirements are growing due to the energy transition and, among other things, the resulting need to transmit electricity over long distances. Since grid expansion is not progressing as fast as the growth in renewables, grid bottlenecks are increasingly emerging, which the TSOs must resolve.
The effectiveness of grid expansion in Germany is particularly evident from one example in the VDE FNN statistics: The completion of the “Südwest-Kuppelleitung” (aka “Thuringian Power Bridge”) on all three sections in the 50Hertz control area in September 2017 has led to a significant reduction in TSO measures since 2018 and consequently to lower costs for redispatch and compensation – a fact that 50Hertz itself has clearly pointed out in 2019.