Power supply situation tense in winter, but not "at risk"

The security of electricity supply in Switzerland is not at risk in the winter of 2022/2023, but supply bottlenecks cannot be completely ruled out. This is the Conclusion of a study on behalf of the Swiss Federal Office of Energy, accompanied by the Electricity Commission Elcom and the Federal Office for Land Economic Supply (BWL).

In the study, various scenarios with different availabilities of gas and nuclear power plants were investigated and simulated. The combination of meterological conditions and power plant outages was also run through and the probability of bottlenecks calculated. However, the Federal Council concludes that the measures adopted so far already make a significant contribution to the energy supply in winter.

With a hydropower reserve, energy could be shifted to the critical period at the end of winter. The provision of a temporary reserve power plant in Birr, Aargau, and other reserve power plants and emergency power groups could also move additional energy into the system. Other measures include increasing capacity in the transmission grid, providing a bailout for system-critical power companies, and temporarily reducing the residual water levy.

Different model scenarios

The reference scenario assumes that the availability of French nuclear power plants is reduced by 35 percent in the winter of 2022/2023, but that there is sufficient gas available across Europe to generate electricity. The calculations showed that sufficient energy from domestic and foreign production would be available to meet Swiss electricity demand in this scenario. The prerequisite, however, is that market-based electricity trading in Europe continues to function and that mutual support in shortage situations is guaranteed.

Gas shortage scenarioHere, it is assumed that electricity production throughout Europe is restricted by around 15 percent. In a majority (87 percent) of the approximately 2400 simulations for this scenario, there is no electricity supply shortage in Switzerland. In 8 percent of the simulations, the missing amount of electricity corresponds to more than one winter day's consumption (ENS: Energy Not Served), which is around 170 GWh. In five percent, the amount of electricity missing in winter is equivalent to more than two and a half winter day's consumption. The hydropower reserve, reserve power plants and emergency power groups are available to deal with such cases, and conservation efforts also play their part.

Nuclear power outage scenarioIf as much as 50 percent of the nuclear power plant fleet in France and, in addition, the Swiss nuclear power plants Leibstadt and Beznau 1 were to fail in winter, regionally tense situations could arise in Europe, which, however, would not extend to Switzerland, according to the federal government, thanks to the available hydropower and sufficient import capacities from the other neighboring zones.

Extreme scenario: The combination of restricted gas availability across Europe and the unavailability of all Swiss nuclear power plants would have a significant impact on Switzerland. In such a scenario, which is, however, very unlikely, an average amount of electricity equivalent to almost six typical winter days' consumption would be missing in winter.

Source: Bund/Editorial