It is estimated that fossil fuel power plants used for electricity production are responsible for a quarter of the total greenhouse gas emissions in Europe. However, in Switzerland electricity is mainly produced by nuclear and hydroelectric power plants; this production accounts for 2% of GHG emissions.
The country also relies on imports from neighboring countries to meet its needs. This represents 11% of the electricity consumed. But, this electricity originates from power stations that are highly “carbon intensive.”
In order to decarbonise Switzerland, a team of scientists from the UNIGE and Empa has developed various energy scenarios and defined the best path to follow.
“We developed seven different scenarios that include solar, wind and hydropower energy with varying degrees. All of this with and without the use of nuclear power as Switzerland envisages a gradual withdrawal from this mode of production by 2050,” explains Elliot Romano, a senior scientist in the F.-A. Forel Department of Environmental and Water Sciences at the UNIGE Faculty of Science.
After studying several options, the research team determined that the optimal scenario would be a mix of photovoltaic and wind generation. The model is based on a large wind power production of 12 TWh and solar power production of 25 TWh. Compared to a nuclear power solution, the proposed production mix reduces the import requirement from 16 TWh to 13.7 TWh.
Nonetheless, this scenario, taking into account future electricity needs, would increase the carbon footprint of consumption from 89g of CO2 per kWh (in 2018) to 131g of CO2 per kWh in the future. However, the electrification of these needs as a whole would ultimately reduce Switzerland’s contribution to GHG emissions by 45%. The researchers also showed that the current storage facilities would only be able to partially manage the summer electricity surpluses, which would result from the large capacity of the photovoltaic power plants in operation at the time.
“Until now, research on the footprint of electricity production has been based on average consumption values, particularly annual values. The strength of our study lies in the use of hourly values and therefore much more precise,” explains Elliot Romano. The direct but also the indirect footprint of this production was also integrated. “We took into account the footprint generated, for example, by the production of the concrete used in the construction of a power plant. This method, therefore, enabled us to carry out a comprehensive analysis of the life cycle of electricity production.”
This method and the unprecedentedly precise data provide concrete guidelines for Switzerland’s 2050 energy strategy.