Nuclear energy is already one of the foundations of Czechia’s electricity system. The country is not debating whether to introduce nuclear power for the first time. It is deciding how to preserve and expand a mature nuclear fleet while coal generation declines and electricity demand becomes more closely connected to industrial competitiveness, heating, transport, and wider electrification.
Six operating reactors at Dukovany and Temelín provide Czechia with almost 4,000 MW of net nuclear capacity. Together, they have commonly supplied around two-fifths of the country’s electricity. Nuclear generation reached a record 32.066 TWh in 2025, demonstrating that the existing plants remain major productive assets rather than facilities approaching immediate retirement.
The central question is therefore one of timing. Czechia must keep its current reactors operating safely for longer while preparing replacement and additional capacity that will not enter service until the 2030s.
Dukovany and Temelín Give Czechia an Established Nuclear Base
The Dukovany Nuclear Power Plant in the Vysočina Region contains four pressurized-water reactors that began supplying electricity between 1985 and 1987. The units are based on the Soviet-designed VVER-440 platform, although decades of modernization have changed many plant systems, operating practices, and safety features.
Dukovany remains important because its four reactors provide steady generation within a relatively compact site. The plant also supports a large technical workforce and a domestic network of engineering, maintenance, testing, and component suppliers. Its value extends beyond the electricity produced during any single year.
Temelín, located in South Bohemia, entered operation much later. Its two larger VVER-1000 reactors began generating electricity around the start of the 2000s. Temelín is Czechia’s largest individual electricity-generating site and an important source of low-carbon power for the national grid.
The two stations give Czechia something that many countries seeking nuclear energy still need to build: an experienced operator, an established regulator, trained engineers, specialized suppliers, operating procedures, and public institutions familiar with nuclear safety. ČEZ operates both plants, while the State Office for Nuclear Safety, known as SÚJB, regulates the sector.
This existing nuclear system makes expansion more practical, but it does not make new construction simple. Large reactor projects require long licensing periods, major state involvement, stable financing, grid planning, and political support across several governments.
Two New Dukovany Units Move From Tender to Delivery
Czechia’s most important nuclear development is the construction of two new units at Dukovany. In June 2025, Elektrárna Dukovany II and Korea Hydro & Nuclear Power signed an engineering, procurement, and construction contract covering both reactors.
The project company is majority owned by the Czech state, with ČEZ retaining a minority interest. This structure places the state at the center of financing and delivery while preserving access to ČEZ’s technical knowledge and operating experience.
The contract also includes an option for two possible additional reactors at Temelín. This does not mean that four reactors are certain to be built. It gives Czechia a route toward further expansion if future electricity demand, financing conditions, and energy policy support another major project.
Dukovany was prioritized partly because the existing units will eventually need replacement. Even with extended operation, reactors commissioned in the 1980s cannot remain the permanent foundation of the system. The new units are intended to prevent a major fall in nuclear generation when the older plant finally retires.
The schedule aims to bring the new capacity into operation during the 2030s. Before construction can reach its most visible stages, the project must complete detailed engineering, nuclear licensing, site preparation, supply-chain contracting, and supporting infrastructure.
The scale of the program will also affect the surrounding region. New housing, roads, public transport, technical education, healthcare capacity, and municipal services will be needed for the construction workforce. The project is therefore both an energy investment and a long-term regional development program.
Czech Industry Is Expected to Take a Large Role
The Dukovany expansion is designed to involve Czech companies rather than function only as an imported turnkey plant. When the main contract was signed, the government reported that around 30% of expected industrial participation had been identified, with a target of reaching approximately 60% by the end of construction.
Companies connected to turbine equipment, civil engineering, control systems, nuclear services, testing, and plant maintenance are positioned to participate. Agreements have involved businesses such as Škoda Power, Škoda JS, ÚJV Řež, Metrostav DIZ, ZAT, I&C Energo, and NUVIA.
Domestic participation matters for several reasons. It keeps a larger share of project spending inside Czechia, supports highly skilled employment, and gives local companies references that may help them compete for nuclear contracts elsewhere. It can also improve the availability of maintenance and engineering support during the plant’s operating life.
However, localization must be based on qualified nuclear-grade supply rather than a percentage alone. Components and services must meet strict quality, documentation, traceability, and safety requirements. The program’s industrial value will depend on whether Czech firms gain lasting capabilities rather than only short-term construction work.
Longer Reactor Lifetimes Will Bridge the Generation Gap
New Dukovany reactors will not replace the existing plant immediately. Czechia is simultaneously preparing for much longer operation of its current units.
ČEZ has previously planned around operating both Dukovany and Temelín for at least 60 years. In 2026, the government and operator also began discussing the technical preparation required for the Dukovany units to operate for as long as 80 years.
An 80-year operating period is an objective rather than an automatic extension. Continued operation depends on inspections, equipment replacement, aging-management programs, safety assessments, regulatory approval, and the condition of components that cannot easily be replaced.
The strategy reflects the difficulty of matching retirement and replacement dates. If Dukovany’s existing reactors closed before sufficient new capacity was available, Czechia could face a substantial loss of reliable domestic generation. Longer operation gives the country more time to complete the new units without creating a sudden electricity gap.
Temelín is younger and may operate beyond 2060 if future technical reviews continue to support it. Investment in turbines, instrumentation, control systems, fuel management, and plant safety is also helping the existing fleet produce more electricity without constructing additional reactors immediately.
Nuclear Fuel Diversification Has Become an Energy-Security Priority
Czechia’s reactors were historically closely connected to Russian nuclear fuel supply. That dependence became a more urgent energy-security issue following Russia’s invasion of Ukraine.
ČEZ has since broadened its fuel and fuel-cycle relationships. Westinghouse and Framatome were selected to supply fuel for Temelín, while Westinghouse produced the first alternative fuel assemblies delivered to Dukovany in 2025. Czechia has also developed uranium, conversion, and enrichment arrangements with suppliers in several countries.
Changing nuclear fuel supply is more complex than replacing one commercial vendor with another. Fuel assemblies must be designed and licensed for a specific reactor type. Their behavior must be evaluated under operating and accident conditions, and the regulator must approve their use.
The result is not complete independence from international supply chains. Nuclear power always requires specialized global suppliers. The objective is to prevent the country’s reactors from depending on a single politically exposed source.
Strategic fuel inventories provide another layer of protection. Because nuclear fuel occupies little physical space compared with the energy it produces, plants can hold enough material to support operation during shorter supply disruptions.
Small Modular Reactors Could Extend Nuclear Power Beyond Two Sites
Large reactors at Dukovany remain the main expansion program, but Czechia is also developing a small modular reactor strategy. ČEZ selected Rolls-Royce SMR as its strategic partner and acquired a substantial minority interest in the British reactor developer.
The first Czech SMR is planned for the Temelín site, potentially during the mid-2030s. Existing nuclear sites are attractive because they already have grid connections, technical staff, security arrangements, cooling infrastructure, and local familiarity with nuclear operations.
Other possible locations include former or retiring coal-generation sites such as Tušimice and Dětmarovice. Reusing these sites could preserve energy employment and take advantage of existing transmission infrastructure as coal plants close.
The SMR program should still be viewed as a developing option rather than guaranteed capacity. The Rolls-Royce design must complete regulatory approval, establish a production system, and demonstrate that standardized construction can control costs and schedules. Czech deployment will also depend partly on progress made by the first projects in the United Kingdom.
If successful, SMRs could supply electricity, industrial energy, or district heat in locations where a full-sized reactor would be too large. They would complement rather than replace the new Dukovany units.
Spent Fuel and District Heating Expand the Nuclear Agenda
Czechia stores spent nuclear fuel first in reactor pools and later in dry storage facilities at Dukovany and Temelín. This system can safely hold fuel for decades, but it is not intended to be the final disposal solution.
The country has reduced its search for a deep geological repository to four candidate areas. Detailed geological work, including mapping, geophysical studies, groundwater analysis, and borehole drilling, is being used to compare the sites. The current program aims for a repository to begin operation around 2050.
Local acceptance will remain important. Geological suitability is essential, but repository development also affects municipalities, land use, public trust, and long-term regional planning.
Nuclear heat is another growing part of Czech policy. Temelín already supplies heat through a pipeline to České Budějovice, reducing the city’s need for separate fossil-fuel heating. A much larger heat connection between Dukovany and Brno is also being developed.
These projects could increase the useful energy obtained from nuclear plants beyond electricity generation. Their commercial value will depend on pipeline costs, heat demand, distance, and the ability to integrate nuclear heat into existing district-heating networks.
Czechia Is Committing to Nuclear Power for the Long Term
Czechia’s nuclear strategy combines three different time horizons. Modernization and longer operation protect generation from the six existing reactors. Two new Dukovany units are intended to provide large-scale replacement and expansion during the 2030s. Small modular reactors may later bring nuclear power to additional industrial and former coal sites.
The main test is no longer whether Czechia supports nuclear energy. That policy direction is clear. The decisive issues will be construction performance, financing, domestic supplier readiness, regulatory capacity, and the ability to coordinate new reactors with the retirement of coal and, eventually, the oldest Dukovany units.
