Nuclear power in Switzerland is generated by four nuclear power plants, with a total of five operational reactors (see list below). In 2013, they produced 24.8 terawatt-hours (TWh) of electricity, down 5.8% from 2007, when 26.4 TWh were produced. Nuclear power accounted for 36.4% of the nation's gross electricity generation of 68.3 TWh, while 57.9% was produced by hydroelectric plants and 5.7% came from conventional thermal power stations and non-hydro renewable energy sources.
In addition, there are a number of research reactors in Switzerland, such as the CROCUS reactor at the École Polytechnique Fédérale de Lausanne. Switzerland uses nuclear energy only for peaceful purposes. Any project for the adoption of nuclear weapons was definitively dropped in 1988.
In 2011, the federal authorities decided to gradually phase out nuclear power in Switzerland as a consequence of the Fukushima accident in Japan. In late 2013 the operator BKW decided to cease all electrical generation in 2019 in the Mühleberg plant, which has a similar design to Fukushima. Axpo is expected to come up with a similar decision for its aging Beznau Nuclear Power Plant, which houses the oldest commercial reactor of the world.
As of 8 December 2014, the National Council has voted to limit the operational life-time of the Beznau Nuclear Power Plant to 60 years, forcing its two reactors to be decommissioned by 2029 and 2031, respectively. The lower house has also voted in favor of banning the construction of new reactors for commercial usage. However, the adoption of such amendment still has to be confirmed by the Council of States, the upper house of the Federal Assembly of Switzerland. In addition, a citizens' initiative to restrict the operational life-time of nuclear reactors to 45 years will have to be voted upon, irrespective of whether the legislature's amendment will actually come into force or not.