10. 8. 2020

Temelín's Unit 2 restored production of electricity

On Sunday afternoon, Unit 2 of Temelín NPP started to produce electricity again. The operators shut it down as planned for refueling on June 12. The outage lasted 58 days and, during it, the technicians replaced a quarter of the fuel, checked the safety systems, and mastered 55 investment actions. Together with the Dukovany power plant, all six nuclear units are currently in operation.

Temelín's Unit 2 began to produce electricity again at 50 % of the reactor rated power. The technicians are now waiting for the tests at 80 percent of reactor rated power to check the reactor core power distribution. They are also watching closely other technologies, such as new separators, which have been replaced in cooperation with Škoda JS after twenty years of operation in the framework of modernization.

"It was a very challenging investment action that involved 488 subactivities. In terms of dimensions, the handling and subsequent connection to the surrounding technology were very demanding. We verified the device with a series of tests before the unit was connected,"

said Jan Kruml, Director of the TemelÍn Nuclear Power Plant.

From the new separators that remove moisture from the steam passing through the turbine and heat it afterward, CEZ company expects an increase of the unit performance by extra MWe units with environmental benefits.

"The savings will be several thousand tons of carbon dioxide emissions per year that would be generated by coal-fired power plants. However, we can be more specific only after the guarantee measurements that await us after several weeks of operation of the Temelín Unit 2,"

added Bodan Zronek, member of the ČEZ Board of Directors and director of the Nuclear Energy Division of ČEZ.

During the outage, the technicians replaced 42 out of 163 fuel assemblies in the reactor. Inspections of safety systems were also important for the total length of the outage. Three containers of spent fuel were placed in the warehouse on site of the plant. In the framework of the power plant modernization, 55 investment actions were carried out. Altogether, one thousand workers including the suppliers participated in the outage. All work was carried out in compliance with the measures taken in relation to the risk of COVID-19 infection. At the same time, the power engineers planned the outage works so that Unit 2 at Temelín would be connected before the planned disconnection of the Dukovany Unit 2.

In this way, Temelín passed both planned outages this year. Together, they lasted for 117 days and the technicians mastered them with an advance of 1 days.