Units 1 and 2 at Mochovce NPP, Slovakia

Units 1 and 2 at Mochovce NPP, Slovakia

The Mochovce NPP project is closely connected with our history

The Mochovce nuclear power plant is a project that is closely tied to the history of ŠKODA JS – it has been with us to this day. Our involvement in Mochovce NPP started in 1987 when we commenced work as the final supplier of the primary circuit and the fuel-handling part of the power plant.

In the south of Slovakia, between Nitra and Levice, there are two units in operation and two units under construction at the Mochovce nuclear power plant, all four with VVER 440/V-213 pressurized water reactors. The gross power output of the first two units was up-rated from 440 to 470 MWe in 2008.

Stage 1 of construction

According to the original plan, the power plant was to be commissioned at the end of the 1980s. Compared to nuclear units of the same type, the Mochovce project featured several major improvements. A new solution was, for example, the seismic resistance of the plant’s SSC (systems, structures and components). However, at the beginning of the 1990s, the completion of the power plant was hindered by a lack of finance.

Stavba šachty reaktoru na JE Mochovce

The only viable way to ensure that the construction could continue was to search for financial resources abroad. The condition for the participation of foreign capital and the involvement of renowned companies was a comprehensive evaluation of the project and the overall state of the power plant’s equipment. The Mochovce project was subjected to a number of inspections and audits conducted by experts from all over the world, who analyzed the control systems and their safety features. This resulted in a program aimed at increasing nuclear safety, whose implementation was to take place before the commissioning of the power plant.

ŠKODA JS played the role of final supplier of the primary circuit, including the fuel-handling part. Prior to the Mochovce NPP project, we had already gained experience in the construction of eight units with VVER 440 reactors at the Jaslovské Bohunice and Dukovany NPPs. The reactors and other essential components produced in Pilsen represented the fourteenth and fifteenth complete equipment sets in the company’s history. The other reactors were produced for Paks NPP (Hungary), Nord NPP (Germany) and Żarnowiec NPP (Poland).

Completion continues under ŠKODA Slovakia

Velín JE Mochovce

In 1995, the Slovak government decided that the construction of Units 1 and 2 at the Mochovce NPP would continue, and our newly established subsidiary, ŠKODA Slovakia, s.r.o. (later ŠKODA Slovakia, a.s.) started to work on the new project. ŠKODA JS provided the new company with technical support in the areas of design, technical preparation for the installation, sales and completion activities as well as tests and start-up. The first unit at the Mochovce NPP was commissioned in October 1998, the second unit 17 months later, in March 2000.

Compliance with the requirements and criteria of safety measures at Units 1 and 2 of the power plant, revised by the International Atomic Energy Agency (IAEA), laid the foundations for the acceptance of the Completion of Units 3 and 4 at the Mochovce Nuclear Power Plant project by the relevant bodies of the European Union. This project is described in more detail in the reference Units 3 and 4 at the Mochovce Nuclear Power Plant.

Currently, we are involved at the first two units of the Mochovce NPP in regular outages of major and minor projects such as the implementation of part of the EMO12 Large Component Seismic Reinforcement project, crane works during outages, technical supervision by the reactor equipment manufacturer, unsealing and sealing of the primary and secondary lids of the steam generator hot and cold collector, operational inspections, etc.

The history of our cooperation

on Units 1 and 2

Pohled do Reaktorového sálu JE Mochovce

1987-2000 ŠKODA JS was the final supplier of the primary circuit and the fuel handling part in the construction of Units 1 and 2 at Mochovce NPP

Provozní prohlídka tlakové nádoby reaktoru

1998 the first in-service inspection of the reactor pressure vessel in Unit 1 at Mochovce NPP was carried out


Provozní prohlídka tlakové nádoby reaktoru

1999 the first in-service inspection of the reactor pressure vessel in Unit 2 at Mochovce NPP was carried out


Zařízení MKM-3 na měření kroutícího momentu pohonu regulačního orgánu

2000 we supplied the MKM-3 control rod drive tension meter

Utahovák přírubových spojů horního bloku reaktoru

2007 we supplied two special upper block flange joint stud tensioners

Interesting numbers

2reactor pressure vessels
90 control rod drives produced and supplied (between 1985-1988)
6 sections of racks produced and supplied for the storage of 1,364 fuel assemblies (in 1993-1994)
1 KSV 440 cask of ŠKODA JS’s own design for witness samples of pressure vessel steel (1998)