Unit 2 at the Czech Republic’s Temelin nuclear plant was closed down on 12 August because of a defect in the generator’s cooling system in the non-nuclear part of the plant.

The unit had resumed operation on 31 July after a scheduled shutdown of 104 days, which was longer than planned, due to a steam generator leak. The generator is being depressurised and one of the six penetrating openings that has been damaged will be replaced, Temelín spokesman Marek Svitak said.

Temelín 2 reached full performance on 2 August following 20 days during which Temelín was completely out of operation. Unit 1 was already shut down for its regular maintenance and refuelling outage and is due to be connected to the grid by the end of August. Unit 2’s output has been increased by 2% to 1078MWe after the installation of new rotors. The turbine in unit one was upgraded last year.

Power company CEZ says its customers will not be impacted by the shutdown of both units as the electricity shortfall has covered by the purchase of electricity abroad. CEZ spokesman Ladislav Kríž said the company has almost constantly sold out the electricity it produces and only a small part is available for daily trading. "In case of unexpected events, we will buy electricity on the markets. This would be nothing exceptional," he added.

Temelin has produced 7.95TWh of electricity this year but because of the extended shutdown of unit 2 will not surpass its 2012 record, when it generated 15.3TWh.

In May, Prime Minister Bohuslav Sobotka said the government planned to build two new nuclear power units -the first Dukovany nuclear plant and the second at Temelin. The tender for construction of the first unit will be announced before the end of 2016, he added.