The grid frequency is 50 Hertz (Hz) throughout Europe. It fluctuates depending on the actual grid load. If more electricity is generated than is being consumed, the frequency is higher than 50 Hz. By contrast, if more electricity is consumed than is being generated, it is lower. The diagram shows these actual deviations.
The volume of energy used by consumers connected to the transmission grid is referred to as the vertical load. The diagram compares the monthly peak values of the vertical load.
The volume of electrical energy that flows into the transmission grid in Switzerland is referred to as vertical feed-in. It is primarily supplied by power plants connected directly to the transmission grid.
The net feed-out is obtained by deducting the feed-in from the feed-out.