The nominal grid frequency in the European interconnected grids is 50 Hz. The grid frequency is a key indicator of the grid status, measured locally but with supra-regional significance. It reflects the essential balance between the generation and consumption of electrical energy. Maintaining a stable frequency is of enormous importance for the functioning of the electricity grid and the associated generators and consumers. However, major and minor deviations from the target frequency of 50 Hz occur continuously. Normally, due to stochastic effects, the grid frequency fluctuates around 50 Hz in a +/- 20 mHz wide corridor, i.e. between 49.98 and 50.02 Hz.

However, there are also large deviations from the nominal frequency again and again, i.e. the +/- 20 mHz corridor is left. There are many reasons for this, from power plant outages, unexpected major events or simply misforecasts of weather and consumption

Regular, recurring variations in the frequency of the power grid are caused by electricity trading. Market time units are 15 minutes in length and have significant influence on the frequency of the power grid. The fluctuations are caused by transitions of delivery actions from power plant A -> power plant B. For example, at the change of hour, power plant A reduces production, and power plant B takes over the supply task from power plant A. These supply transitions by different power plants cannot always be conducted completely seamlessly and cause fluctuations in the power system frequency due to the power imbalance between generation and consumption. 

In the graph you can see the frequency curves of the last 75 minutes with a delay of 15 minutes. For example, look at the frequency behavior around the hour break. The graph is updated every 60 seconds.

Compare the frequency pattern in continental Europe with that in England or Scandinavia. You will quickly realize how important the size of the grid is for grid stability. But different generation situations between the grids also have an effect on grid stability and the fluctuation behavior of the frequency.

Take a look at the illustrations in parallel, for example, when a storm moves across Europe or when there is a split in the connecting lines between the synchronous areas, the so-called interconnectors.

The Gridradar Alert System informs traders, producers and large consumers in real time when unusual events occur in the grid. Please feel free to contact us.