An International Energy Agency (IEA) report, “Energy Policies of IEA Countries: Switzerland Review 2018”, launched on 9 October, warns that Switzerland’s planned nuclear phaseout, starting in 2019, will change the domestic production profile and could lead to an increase in energy imports.
Currently Switzerland “has the lowest carbon-intensity of its energy supply among all IEA countries thanks to a largely carbon-free electricity sector dominated by hydropower and nuclear generation”, the IEA notes.
However the phaseout, beginning with closure of the single-unit Mühleberg nuclear plant in December 2019, raises questions about security of supply, particularly during the winter when electricity demand is higher than domestic production.
IEA deputy dxecutive director Paul Simons explained that Switzerland’s abundant hydro pumped storage and reservoir capacities will be vital resources for the energy transition.
The report says “filling the gap left by nuclear power station closures while maintaining low-carbon generation and high standards of supply security will be challenging”. It notes that, although Switzerland’s Energy Strategy 2050 proposes a low-carbon economy with higher energy efficiency and renewable energy sources replacing nuclear energy, “more ambitious reforms in the energy sector are needed to address security of supply questions”.
Switzerland’s nuclear phaseout will create an energy gap of at least 20TWh a year that will need to be replaced with other generation technologies, possibly including new fossil fuel capacity, the report notes. If Switzerland is to achieve its climate targets, it will require additional emissions reductions in other sectors to compensate for possible higher fossil fuel power generation.
Nuclear power provides around 45% of the Switzerland’s power generation in winter when hydro reservoirs are low. It is therefore primarily facing an energy and not a capacity challenge, the report says. It adds that Switzerland’s five commercial nuclear reactor units are a valued part of its “extremely low-carbon electricity mix” and can remain so if plant operators continue to demonstrate safe operation. Additional renewable capacity may not be brought online in time to fully replace the phasing out of nuclear plants after some 50 years of operation, the report says.
The report notes that nuclear power has provided a high and stable share of Switzerland’s energy supply since the 1980s, accounting for 22% of the total primary energy supply in 2017. Nuclear accounted for 16% of the installed capacity in 2016 and generated 34% of total electricity in 2017, which was the sixth highest among IEA member countries.
The Swiss government should therefore consider whether nuclear operators should plan to continue operating beyond 50 years, the report says. Clear policies are needed because of the investments and lead times required to refurbish nuclear plants and receive approval to operate for additional 10-year periods.
A new Swiss energy policy was developed following the March 2011 Fukushima accident with both the Swiss parliament and government deciding to phase out nuclear power production. The Energy Strategy 2050 initiative, drawn up by the Federal Council, calls for a gradual withdrawal from nuclear energy. It envisages expanded use of renewables and hydropower but anticipates increased reliance on fossil fuels and electricity imports as an interim measure. In a May 2017 referendum, Switzerland voted to approve a revision to the country's energy policy in favour of renewable energy sources and energy conservation. The revised Federal Energy Act prohibits the construction of new nuclear reactors.
Photo: The Mühleberg Nuclear Power Plant will be the first Swiss unit to close in December 2019 © BKW (JPG)