It is easy to think the electricity consumed in Switzerland is fairly clean. However, there are significant differences between the source of what is consumed and what is produced. To help clear up the confusion, a team of experts at the University of Geneva (UNIGE) created a tool that shows the source of electricity consumed in Switzerland at any given hour of any given day.
For example, in the hour leading up to midnight on 21 December 2022, the latest time period presented at the time of publishing, 55% of the electricity consumed in Switzerland was produced by burning gas. Another 32% was produced from nuclear, 2% from oil and 12% from river water flow. In addition, 56% of total consumption was imported. The imported electricity came from Germany (48%), France (38%) and Austria (15%). This imported electricity was nearly all produced by burning fossil fuels.
2,324 tons of CO2 equivalent emissions related to the electricity consumed during this hour were produced, an average of 311 kg per MWh. Electricity from renewable sources accounted for only 12% of consumption during this one hour time period.
Emissions are particularly high at off peak hours during the winter season. Consumption is higher during winter and imports of (dirty) power are higher at off peak times.
Over the course of an entire year the carbon intensity of Switzerland’s power consumption is lower. Across a whole year the percentage of imported electricity consumed in Switzerland falls to 11% and the average emissions fall to 98 kg per MWh (2018 figures).
Consumers can opt to buy green electricity. However, this does not mean they will end up consuming green electricity. These guarantees of greeness do not guarantee that you will receive green electricity. However, they are not worthless. They essentially act as a way to reward green electricity producers. Put another way, they guarantee that a kWh of green electricity is put into the grid. It just may not be the kWh you consume.
So where does this leave us?
The UNIGE platform highlights the value of consuming less electricity regardless of how your local electricity is produced. It also undermines the generalisation that off peak nighttime consumption is cleaner and that electricity produced by burning fossil fuel can be avoided by opting to buy green power.
In the end putting in more clean power and taking out less, however it may be produced, is what matters. At the same time, if consuming potentially dirty electricity substitutes an unavoidable and even higher emission alternative, consuming electricity may still be the least worse option – better but still polluting.