Various grid levels transport electricity

The entire Swiss electricity grid consists of over 250,000 kilometres of lines and is made up of a transmission and a distribution grid. On its way to consumers, electrical voltage is reduced incrementally from 380,000 volts (380 kV) or 220,000 volts (220 kV) of extra-high voltage in the transmission grid to 230 V in households and businesses.

The Swiss electricity grid is divided into seven grid levels. Apart from the extra-high, high, medium and low-voltage power grid, there are also three transformation levels.


Extra-high voltage in the transmission system (level 1)

The transmission grid absorbs the electricity produced by the big power plants or in neighbouring countries. The electricity is transported at a voltage of 380 kV or 220 kV to the vicinity of the consumer. Here it is fed into the lower grid levels, the distribution grids. The Swiss transmission grid is the property of Swissgrid.

High voltage in the supra-regional distribution system (level 3)

In the high voltage level (> 36 kV - 150 kV) electricity is distributed for supra-regional supply to cantonal, regional and municipal distribution grid operators and to major industrial plants.

Medium voltage in the regional distribution system (level 5)

Medium voltage (1 kV - 36 kV) is used for the regional distribution of electricity. Local distribution grids supply individual suburbs or villages and small and medium-sized industrial enterprises.

Low voltage in the local distribution system (level 7)

The electricity arrives as low voltage (< 1 kV) in homes and agricultural and commercial businesses.


The substation connects two voltage levels. The core of a substation is the transformer, which converts the voltage from one voltage level to another: from extra-high voltage to high voltage and from high voltage to medium voltage.

Transformer stations

Medium voltage is converted to the low voltages of 400 V required in homes and businesses in the transformer station.