Czech Temelín nuclear power plant plans to shut down Unit 2 for turbine adjustments

The Temelín Nuclear Power Plant plans to disconnect Unit 2 from the transmission grid on Wednesday, 16 April. The reason is adjustments to the turbine-generator set in the plant’s non-nuclear section. Operators will not cool down the reactor. They will keep it in what is known as a hot state, allowing the work to be carried out and the unit to return to operation more quickly. Marek Sviták, spokesperson for the Temelín plant, announced this today.

The unit will generate electricity at full capacity until Easter. „This is not a response to an urgent need. We want to adjust some parameters of the turbine’s bearing arrangement, thereby avoiding any unplanned adjustments during the following approximately year of operation, before the next scheduled outage in the already extended fuel cycle. We will use the Easter holidays for the brief interruption in generation, as demand and electricity prices are regularly lower then,“ Sviták said.

Last year, energy technicians adjusted the turbine bearings on both units. The turbine-generator sets at Temelín are the largest equipment of their kind in the Czech Republic. The high-pressure section, three low-pressure sections and generator together measure 65 metres in length. When heated to operating temperature, they expand by approximately three centimetres, while remaining completely sealed. That is why these machines are designed to allow axial movement. The turbine-generator set weighs more than 2000 tonnes, and the tip speed of its longest blades exceeds twice the speed of sound.

Temelín covers roughly one-fifth of domestic consumption. Since the start of this year, it has generated 4.7 terawatt-hours of electricity, compared with 14.3 terawatt-hours last year.