# Nuclear power in Slovakia

Slovakia has five operational nuclear reactors, with a combined net power capacity of 2,308 MWe, with a sixth coming on line shortly. Within the EU, Slovakia is one of the pro-nuclear Visegrád Group nations.
In 2018, nuclear power produced approximately 55% of the country’s electricity. With the additional two reactors starting in 2023, Slovakia is now in a position to be a net exporter of nuclear electricity. The country has two sites for its atomic projects: Bohunice Nuclear Power Plant (BNPP) and Mochovce Nuclear Power Plant (MNPP).

## History

Slovakia’s nuclear energy development has been driven by political strategy and economic necessity rather than purely technical factors. During the communist era, Czechoslovakia sought energy independence from Western imports, leading to the construction of the Bohunice A1 reactor in the 1960s. However, a major accident in 1977 forced its shutdown, prompting the government to rely on Soviet-designed VVER reactors at Bohunice NPP V1 and V2, reflecting the country’s strong political and economic ties to the Soviet Union.
By the late 1980s, the government initiated the Mochovce Nuclear Power Plant project to further strengthen energy security. However, after the dissolution of Czechoslovakia in 1993, Slovakia faced financial difficulties, delaying completion. The government prioritized finishing Mochovce but lacked funding. Western financial aid, particularly from the European Bank for Reconstruction and Development (EBRD), helped restart the project, though it came with conditions, such as safety upgrades and alignment with European Union regulations. Units 1 and 2 were completed in 1998 and 2000.
By the late 1990s, nuclear power dominated Slovakia’s energy sector, ensuring energy security. However, as Slovakia pursued EU membership, political pressure mounted to shut down older Soviet-era reactors. Despite domestic opposition, Slovakia agreed to close Bohunice V1 in the 2000s as part of EU accession negotiations, marking a controversial shift influenced by international politics rather than national energy needs.

## Reactors

Two V-213 reactors, designed by Atomenergoproekt and built by Skoda at the Bohunice V2 plant. The V2 units construction began in 1976 and commenced operation in 1984 and 1985 and each provide 466 MWe.
In 1982 construction on two units of the planned four-unit Mochovce nuclear power plant was commenced by Skoda, using VVER-440 V-213 reactor units, they were commissioned between 1998 and 1999. Originally 405 MWe, they were upgraded in 2008 to 438 MWe.
The government of Slovakia has been committed to nuclear power, and two new reactors began construction at MNPP in 1987, but were suspended in 1992. The project reactivated in 2009.
The two new reactors at Mochovce have a net electrical capacity of 440 MW each. Enel, an Italian power company and 50% shareholder of Slovenske Elektrarne, initially planned an investment of €1.6 billion for the completion of the MNPP units 3 and 4 by 2011–2012. In January 2006 the Slovak government approved a new energy strategy incorporating these plans, with capacity uprates at MNPP units 1 and 2, and at BNPP units 3 and 4.
Mochovce-3 came on-line in January 2023. Mochovce-4 is due to follow within a year.
In August 2023 Slovakia signed an agreement to receive nuclear fuel from the American company Westinghouse as a step towards moving away from Russian source fuels. Slovakia is also talking to France's Framatome to work together on the development of a nuclear fuel for VVER-440 pressurised water reactors.

### Future development

A proposal was put forward in February 2023 for permission to build unit 5 at Bohunice. The new reactor has an expected output of 1,200 megawatts. The utility Slovenske Elektrarne is the commissioner.
In July 2023 an agreement with Westinghouse was signed on the potential deployment of its AP1000 and AP300 small modular reactors in Slovakia.
In 2024, Slovakia approved plans for a new Nuclear reactor at the Jaslovské Bohunice site. The proposed unit, with a capacity of up to 1,200 MW, aims to enhance energy security and self-sufficiency. The government is working on a comprehensive plan to outline suppliers, timelines, and financing by October 2024. Potential international partners, including South Korea, France, and the United States, are being considered for the project. Prime Minister Robert Fico has already engaged in discussions with South Korean officials to explore cooperation. This project reflects Slovakia's ongoing commitment to nuclear energy.

## Reactors deactivated and decommissioned

Three reactors have been deactivated.
* 110 MWe Russian-designed Bohunice A1 reactor, built by Skoda, completed in 1972 and ran until 1977 when it was closed due an accident arising from refuelling.
* Two VVER-440 V-230 reactors at the Bohunice V1 plant, supplied by Atomenergoexport of Russia and Skoda, completed in 1978 and 1980, closed in 2006 and 2008.
Prior to its accession to the European Union, Slovakia had to shut down two of its older reactors at Bohunice, because they did not meet European safety standards. Although Slovakia spent significant effort to achieve WANO standards, the EU insisted on the shutdowns. The first plant closed 31 December 2006 and the second on 31 December 2008. The closure of these units, prior to the completion of two new reactors has left the country short on power and Slovakia became an energy importer after the first plant was shut down.
At Bohunice, two reactors of the V1 plant have been deactivated. The total cost of decommission and dismantling of Bohunice V1 by 2025 is estimated at €1.14 billion.
The first reactor pressure vessel was removed from Bohunice V1 on June 3, 2020. It is the first decommissioning of a VVER 440 plant to be completed. The process was completed amid health and safety regulations in place to prevent the spread of the coronavirus.

## Waste disposal

Radioactive waste in Slovakia is disposed without reprocessing. The spent fuel stays at the reactor site; however, some spent fuel has been exported to Russia. Slovakia has also begun a search for a high-level waste repository and established a fund with approximately €775 million to build it.