The frequency of the European electricity system experienced variations on January 10th, 2019 under the form of a drop in the frequency, measured at 49,81 Hz at 21:00. This frequency drop (that does not constitute in itself a black-out risk) was explained by several factors:
The modification of cross-border exchanges schedules between European countries;
The mismeasurement of exchanges between Germany and Austria;
Europe continues to face a constant frequency deviation due to the situation between Kosovo and Serbia (read Did you know? European clocks have been delayed due to electric imbalances caused by Balkans countries)
The mobilisation of the frequency containment reserve in each European country, and in France, of the interruptible load programme, made it possible to bring the frequency back to 50 Hz enabling to get the situation under control.
Source: RTE "January 10th : RTE calls on interruptible industrialists"