Beznau Nuclear Power Plant

Beznau Nuclear Power Plant
Name	Beznau Nuclear Power Plant
Country	Switzerland
Location	Canton of Aargau
Status	Operational
Construction began	1965
Commissioned	1969
Owner	Axpo
Operator	Axpo
Reactor type	Pressurized water reactor
Reactor supplier	Westinghouse Electric Company
Cooling source	Aare
Nameplate cap	365 MW (each)

Beznau Nuclear Power Plant is a nuclear power station located in the Canton of Aargau in northern Switzerland. Owned and operated by the Swiss energy company Axpo, it is the oldest commercial nuclear power plant in the world still in operation. The facility consists of two identical pressurized water reactor units situated on an artificial island in the Aare river, a tributary of the Rhine.

History

The decision to construct the plant was made in the early 1960s during a period of rapid economic growth and increasing electricity demand in Switzerland. Construction began in 1965 under the leadership of the then-utility Nordostschweizerische Kraftwerke, with the Westinghouse Electric Company providing the reactor technology. Unit 1 was connected to the Swiss transmission grid in 1969, followed by Unit 2 in 1972. The plant's location on the Aare was strategically chosen for its abundant cooling water and proximity to major load centers like Zürich.

Design and technical specifications

Each of the two units at the site is a pressurized water reactor with a net electrical output of 365 MW. The reactors were supplied by the American firm Westinghouse Electric Company, while the turbine generators were manufactured by BBC Brown Boveri. The containment structures are of a pre-stressed concrete design. The plant draws cooling water directly from the Aare, and its electrical output is fed into the high-voltage network operated by Swissgrid. Over the decades, numerous upgrades have been implemented, including enhancements to the emergency core cooling system and the installation of a vented filtered containment system.

Operational history

Since commissioning, the plant has been a cornerstone of electricity supply in the region, typically providing about 6% of Switzerland's total power generation. It has undergone several major refurbishment and modernization campaigns to extend its operational life, most notably a comprehensive safety upgrade program following the Fukushima Daiichi nuclear disaster in Japan. In 2015, Unit 1 was temporarily taken offline after the discovery of manufacturing flaws in the reactor pressure vessel forgings supplied by Schmiedewerke Gröditz, leading to extensive inspections and analyses supervised by the Swiss Federal Nuclear Safety Inspectorate.

Safety and incidents

The plant's safety record is overseen by the Swiss Federal Nuclear Safety Inspectorate (ENSI). A significant incident occurred in 2012 when it was revealed that crucial safety documents had been partially plagiarized from an older German plant, leading to a temporary operational ban and a major review of safety culture by Axpo. The aforementioned flaw findings in the reactor pressure vessel in 2015 prompted a long-term shutdown and international scrutiny, involving experts from the United States Nuclear Regulatory Commission and the European Union. The plant's design has been repeatedly assessed for resilience against external hazards like earthquakes and aircraft crashes.

Decommissioning and waste management

Under the revised Swiss Energy Strategy 2050, the plant is permitted to operate as long as it meets strict safety standards, with no fixed shutdown date. Preparations for eventual decommissioning are ongoing, with funds collected in the national decommissioning fund for nuclear facilities. Axpo is responsible for the future dismantling of the plant. All spent nuclear fuel is currently stored in an on-site interim storage facility before its planned transfer to a deep geological repository, as mandated by the Nuclear Energy Act and overseen by Nagra, the Swiss cooperative for radioactive waste management.

Cultural and political significance

The plant has been a focal point of the anti-nuclear movement in Switzerland for decades, with major protests occurring in the 1970s and during the debates following the Chernobyl disaster and the Fukushima Daiichi nuclear disaster. It frequently features in national referendums on energy policy, such as the 2017 vote on the Energy Strategy 2050. The facility's longevity and its role in the Swiss electricity sector make it a symbol of both technological heritage and ongoing political debate regarding the future of nuclear power in Switzerland.

Category:Nuclear power stations in Switzerland Category:Buildings and structures in the canton of Aargau