Slovakia - World Nuclear Outlook Report

Current operations

Slovakia's five operable VVER-440 units at the Bohunice and Mochovce sites are owned by Slovenské elektrárne. An additional VVER-440 is undergoing commissioning at Mochovce and achieved first criticality in August 2026.

Table Rs.1 Nuclear capacity status (as of 1 October 2026)

Operable reactors Operable reactors net capacity (MWe) Operable reactors gross capacity (MWe) Reactors under construction Reactors under construction gross capacity (MWe) Cumulative carbon dioxide emissions avoided 1970-2025
(cf. coal) (MtCO2)
3 2306 2470 1 471 552

Nuclear policy and outlook

The Slovak government approved plans for a new unit of around 1200 MWe near the Bohunice nuclear power plant in May 2024. In January 2026 Slovakia and the USA signed an intergovernmental agreement covering the development of a new, state-owned 1200 MWe unit at Bohunice that is expected to begin operation by 2041. An April 2026 agreement between Slovakia, the USA and Westinghouse launched preparatory studies for the new unit.

In September 2026 the Slovakia's state-owned decommissioning company JAVYS acquired CEZ's 49% stake in JESS, the company formed to develop new nuclear capacity in Slovakia.

Slovakia is also considering building small modular reactor (SMR) capacity.

In June 2025 Newcleo and JAVYS established a joint venture, now named Newvys, to develop up to four 200 MWe lead-cooled fast reactors at the Bohunice site.

In August 2025 Slovenské elektrárne and Synthos Green Energy signed a memorandum of understanding to explore the possible deployment of GE Vernova Hitachi's BWRX-300 SMRs.

A feasibility study under the US-funded Project Phoenix confirmed in January 2026 that four sites (Bohunice, Mochovce, Vojany and the US Steel Košice site) are suitable for SMR deployment. Slovenské elektrárne has indicated that SMRs could be operational from 2035.

Table Sk.2 Contributions to total capacity projection in 2050

60 year operation (MWe) 80 year operation (MWe) Currently under construction capacity (MWe) Planned capacity (MWe) Proposed capacity (MWe) Potential capacity (MWe) Government capacity target (MWe) Additional capacity* required to meet government target (MWe) Total capacity (MWe)
1470 1000 471 - 1200 - - - 4141
*Capacity additional to operable, under construction, planned, proposed and potential capacities required to meet the government target.
 

Readiness Assessment

Nuclear power in Slovakia has exceptionally strong policy support and mature institutions. A VVER-440 reactor at Mochovce is in advanced stages of commissioning and a new state-owned unit is planned for Bohunice. However, the new unit does not yet have an EPC contract, investment decision or construction licence.

Country Category Expander
Policy Framework Readiness High
Nuclear has strong policy support. An intergovernmental agreement with the USA on a new state-owned Bohunice unit was signed in January 2026. The siting permit for the unit was granted in 2024.
Institutional & Infrastructure Readiness High
Slovakia has an experienced operator and independent regulator, recent construction and commissioning capability through Mochovce 3&4, extensive engineering expertise, mature waste and decommissioning organisations, and strong nuclear education and supply chain capabilities. The new unit will be state-owned, so the ownership and operating arrangements are still to be confirmed.
Programme & Project Development Readiness Moderate-High
Mochovce 4 reached first criticality in August 2026. The Bohunice project has a siting permit, a state-owned project company, government backing, a financial adviser and preparatory studies launched with Westinghouse in April 2026. There is no final EPC contract, investment decision or construction licence for the new unit.
Target Achievability Moderate
A new 1.2 GWe unit operating around 2040-41 is plausible, but substantial financing, contracting, licensing and EU approval work remains. Mochovce 3&4 were expected to start operating in 2012 and 2013, with unit 3 entering commercial operation only in October 2023 and unit 4 still being commissioned in 2026, which shows the potential for major schedule overruns.
World Nuclear News
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