Engineers at Czechia’s Temelín plant replace leaking cooler, unit expected to restart next week

Engineers at the Temelín nuclear power plant have replaced a leaking cooler in an internal system, which led to the unplanned disconnection of the second unit on Wednesday. They are now inspecting the equipment, with further tests scheduled for the weekend. The plant expects the unit could restart next week. Petr Šuleř, head of nuclear communications at ČEZ, told the Czech News Agency (ČTK).

Šuleř said it had been confirmed that the second unit was shut down because of a leak in one of four coolers in the generator’s internal system, in the plant’s non-nuclear section. „The equipment has cooled down, and engineers have already replaced the cooler in question. They are currently inspecting the equipment in preparation for the unit’s start-up,“ Šuleř said.

According to the engineers, the timing of the unit’s reconnection to the transmission grid will depend on the results of weekend tests and inspections. The unit will then be heated up and prepared for start-up. „We provisionally expect this to take place during the next working week,“ Šuleř added.

The plant disconnected the second unit unexpectedly on Wednesday morning. The current outage is the first unplanned one since 2019. The work has not affected the primary circuit or the first unit.

Temelín is the country’s largest electricity producer, covering around a fifth of domestic consumption. Last year, it generated 16.1 terawatt-hours (TWh) of electricity.