Electricity is invisible and comes out of the socket. However, the energy we need for all kinds of electrical appliances and for charging electric vehicles does not come from nowhere.
In order for electricity to be used, it must first be generated by producing electrical energy with the aid of power plants. Electrical energy can be generated from light, heat, movement or chemical energy stored in coal or oil, for example. Different types of power plants are needed to generate energy: coal-fired power plants, nuclear power plants, hydroelectric power plants, gas turbine power plants, geothermal power plants, wind power plants and solar power plants. The electric energy generated in this way is transported via the closed power grid to end consumers and their power sockets.
Not all electricity is created equal, however. There are significant differences in the cleanliness of production – a coal-fired power plant emits CO2, which is bad for the climate, while nuclear power plants produce radioactive waste, which is problematic when it comes to disposal. The power of the sun and the wind should be harnessed increasingly and converted into energy in the future. The use of these renewable energies places less of a burden on the environment in terms of waste.
The source of the electricity used is particularly relevant when it comes to charging the battery of an electric vehicle. The cleaner the electricity, the more environmentally friendly the vehicle. The following example shows how extensive the differences can be: The generation of one kilowatt hour of electricity in a coal-fired power plant results in the emission of more than one kilogramme of CO2. If this kilowatt hour of electricity comes from a hydroelectric power plant, however, fewer than 50 grams of CO2 are emitted. This includes the CO2 released during construction and maintenance of the infrastructure.
Switzerland is in a privileged situation when it comes to renewable energies thanks to hydropower. According to the Swiss Federal Office of Energy, in 2019, 75% (2018: 74%) of the electricity produced in Switzerland came from renewable sources: 66% from large-scale hydropower and around 8.4% from photovoltaics, wind, small-scale hydropower and biomass. 19% of the electricity came from nuclear energy, and just under 2% from waste and fossil fuels. For 4% of the electricity supplied, the origin and the composition are not verifiable (2018: 6%), which however is no longer permissible since 2020.
The electricity produced is not the same as the electricity supplied, as Switzerland exports and imports electricity, resulting in a slight shift in the composition of the electricity mix: 56.4% came from hydropower, 35.2% from nuclear energy, 2.6% from fossil fuels, and just below 6% from renewable energies. In the interests of transparency, electricity suppliers in Switzerland have been obliged since 2005 to disclose the origin and composition of the electricity they supply. According to the Swiss Federal Office of Energy website, declarations are always made retroactively, based on the data of the previous calendar year. Suppliers have been required to disclose these figures to all customers with their electricity bills since 2006, and since 2013, the data have also been published on the Internet platform www.stromkennzeichnung.ch.
A glimpse at Switzerland’s largest city reveals that the electricity supplied to electric vehicles at a fast-charging station operated by the Municipal Electric Utility Zurich (EWZ) is 100 per cent certified natural electricity from Switzerland. This is produced exclusively in Swiss hydropower, solar and wind plants, and helps to facilitate sustainable electric mobility.
Electricity is measured and paid for in kilowatt hours (kWh). In Switzerland, a kilowatt hour of electricity costs between CHF 0.10 and CHF 0.40, depending on the region and the chosen rate and electricity mix (night-time rate, green electricity).
This breakdown shows how much it costs on average to fully charge the empty battery of an electric car. It is particularly relevant whether the electricity is taken from a normal socket or from a fast-charging station:
Charging option Charging capacity Time to full charge Cost per charge
Socket 3.7 kW 13:30 h CHF 10.50
Wall box 11 kW 4:30 h CHF 10.50
Charging station* 50 kW 1 h CHF 37.50
* Provider: MOVE fast charging, CHF 2.00 activation fee + CHF 0.10/min. + CHF 0.59/kWh