Fuel unloading begins at Czech Dukovany unit 4, detailed inspections ahead

At the Dukovany Nuclear Power Plant, operators have begun unloading fuel from the reactor of unit 4 for detailed equipment inspections. The unit was shut down as planned on 17 April and will not supply electricity to the grid until approximately the end of June. The fuel is now being gradually placed in an adjacent pool. Once the inspections and servicing are complete, operators will return most of the fuel assemblies to the reactor, replenishing the core with one-fifth fresh fuel. Jana Štefánková, spokesperson for energy company ČEZ, told ČTK today.

Several thousand workers from the power plant and supplier companies are involved in the work planned during the outage. "Unloading the entire reactor core is among the technically most demanding parts of the outage. At the same time, however, it allows us to inspect key reactor and primary circuit equipment in detail before further operation," said Roman Havlín, director of the Dukovany plant.

The plant has four units. According to the results of an analysis by ČEZ, presented this month by Industry and Trade Minister Karel Havlíček (ANO), the units can be operated for up to 80 years from their commissioning, i.e. until 2065 to 2067.

"Outages at our units are far from being just about replacing fuel; above all, they are about systematic equipment maintenance and investment. This is the only way we can ensure planned safe and reliable long-term operation," said Bohdan Zronek, a ČEZ board member and director of the nuclear energy division.

Both Czech nuclear power plants have gradually shifted to extended fuel cycles in recent years. At Dukovany, a 16-month fuel cycle has been standard since 2024, with the units operating for 14 months between outages and outages lasting around two months. Temelín will complete its transition to an 18-month fuel cycle this year, meaning 16 months of operation and an outage of approximately two months. The aim is to increase electricity generation, make more efficient use of nuclear fuel and reduce the burden on equipment, ČEZ said.

The four Dukovany units were commissioned between 1985 and 1987. South Korea's KHNP was awarded the contract to build two additional Dukovany units. Geological surveys for these units began last August. Drilling work was completed this month. The samples are being tested by laboratories in Czechia and Italy. The first new Dukovany unit could be completed in 2036