Will our energy independence deteriorate with the phase-out of nuclear power?

No, not necessarily. Switzerland’s energy independence should even improve with the phasing out of nuclear power, since we import all the enriched uranium rods used in our nuclear power plants. A significant proportion of our nuclear electricity production will be replaced by energy efficiency measures to reduce our consumption and by locally available renewable energies. On the other hand, our security of supply could decline.

Instead, the move away from nuclear power will tend to strengthen our energy self-sufficiency, by putting an end to our imports of nuclear fuel. At worst, our level of energy independence will remain unchanged if we decide to replace all of our nuclear power plants with either electricity imports from neighbouring countries or natural gas imports to power possible gas-fired power plants. In both cases, however, our security of supply would deteriorate.

The advantage of nuclear power is that it offers relatively good security of supply, certainly better than that of electricity or natural gas imports [→ Q21] and [→ Q88]. First of all, uranium ore comes from several countries, ensuring a diversification of supply sources. Second and most importantly, nuclear fuel has a very high energy density. This makes it possible to build up stocks in Switzerland for several years of consumption, since the storage volume required is limited. A power plant the size of Mühleberg consumes about half a cubic metre of enriched uranium rods each year (which corresponds to the volume of a car boot).

It is conceivable that Switzerland could choose to increase both its energy independence and its security of supply by exploiting its own gas resources. It has few conventional natural gas reserves, but has recently discovered several unconventional gas deposits (shale gas and compact gas), particularly under Lake Geneva and in the cantons of Neuchâtel and St. Gallen. St. Gallen is also planning to drill a borehole originally intended for deep geothermal energy [→ Q62]. However, the size of these various deposits remains difficult to assess and the profitability of their exploitation very uncertain. An initial estimate, made in 2014, of Switzerland's unconventional gas potential announces a range of 50 to 150 billion m³ of gas, which would correspond to a reserve for 15 to 45 years at the current rate of our natural gas consumption (3.5 billion m³ per year). A second estimate, made in 2017, suggests a range of 114 to 3,400 billion m³ of gas, but these two studies highlight the great uncertainties of these figures and the technological limitations. Moreover, popular acceptance of this energy source, which is currently highly controversial internationally, is far from certain [→ Q25]. The contribution of these resources to our energy independence thus seems unlikely when our first nuclear power plants are shut down.

Switzerland, on the other hand, is making considerable efforts to promote renewable energy and energy-efficiency solutions. As a result, a theoretically significant proportion of the output of our nuclear power plants will be replaced by solutions based on locally available resources. Our level of energy independence should therefore increase with the decommissioning of our nuclear power plants. The impact on our security of supply, however, is more uncertain.