Unit 4 at Czech nuclear plant Dukovany is not generating electricity due to repairs; unit 3 to be taken offline

Unit 4 at the Dukovany Nuclear Power Plant is not generating electricity and has been disconnected from the grid since 13 March for repairs to two valves in the non-nuclear part of the facility. Electricity supplies are expected to resume over the weekend, or by Monday at the latest, plant spokesperson Jiří Bezděk told the Czech News Agency (ČTK) today. He said the unit has not been shut down but is in so-called hot standby. Today, energy workers will shut down Dukovany’s Unit 3 as planned for a partial fuel replacement and equipment servicing. The outage is expected to end in early June. The plant has four units.

Operators are expected to shut down the reactor at Unit 3 this evening. „Over the weekend, we will cool down the unit. At the same time, we are wrapping up work on Unit 4, which we briefly disconnected from the grid after bringing it back online for repairs and an inspection of two valves in the non-nuclear part of the plant,“ said plant director Roman Havlín.

The planned outage of Dukovany Unit 4 ended on 6 March. The need for repairs became apparent during final tests after the outage was completed, the spokesperson said.

The outage of Unit 3 is scheduled to last 76 days. Energy workers will refine the actual scope based on the results of tests and inspections. Employees of ČEZ and its contractors will also carry out 60 investment projects in the shut-down unit, in addition to replacing part of the fuel with fresh fuel.

Czechia has six nuclear units at two power plants. Last year, Dukovany supplied 14.7 terawatt-hours (TWh) of electricity to the transmission grid, while Temelín generated 15 TWh.

This year marks 40 years since Dukovany’s first unit began operating; it entered trial operation on 3 May 1985. All four Dukovany units have been in operation since July 1987. Last year, the government decided to build two new reactors at Dukovany. They are to be built by South Korean company KHNP, with which ČEZ is now negotiating the final contract. The first of the new reactors is expected to be completed in 2036.