EC requests extra safety for new Mochovce units

16 July 2008

The European Commission has approved the completion of Mochovce 3 and 4 - on condition that Slovakian utility Slovenské Elektrárne (SE) adds additional safety and security measures. Given the equivalent safety of a 'full containment', the project is in line with the Euratom Treaty.


Mochovce units 3 and 4 

Mochovce units 3 and 4 (Image: SE) 

In 1981, construction of the four-unit Mochovce nuclear power plant was commenced by Skoda, using Russian-design VVER 440/213 pressurized water reactor units. Work on units 3 and 4 was started in 1986 and halted in 1992. The first two were completed in 1998 and 2000, respectively, to supply 440 MWe each. Units 1 and 2 have been significantly upgraded and the instrument and control systems replaced with assistance from western companies. Work is currently underway to complete the other two VVER-440 units.

It took one year for EU officials to assess "the safety and security aspects" of Slovakia's application to build the new reactors, with the country's prime minister, Robert Fico, often expressing frustration over the lengthy process.

The discussions centred on whether the Mochovce units should have 'full containment' - additional walls of concrete and steel protecting the reactor. The VVER 440/V213 reactors proposed by SE do not have a 'full containment' structure, which is normal for recent nuclear power plants in Europe and around the world. Slovakia and the EC finally agreed that Mochovce's design did not allow for incorporation of a massive structure there.

However, the EC considered that "an equivalent level of protection as one provided by a 'full containment' has to be ensured." It said that although the project complies with the current national regulations of Slovakia, as well as international recommendations, the recommended set of additional measures is based on an assessment of the best practices available.

The commission recommended that SE - in close collaboration with the national authorities - "evaluates and implements additional features, functional capabilities and management strategies to withstand a potential deterministic impact from an external source (for example a malevolent small aircraft impact) into the design basis of the proposed investment, bringing the design in line with the existing best practices."

The EC stated that, "provided that the commission's recommendations are implemented, the aspects of the investment in question are in line with the objectives of the Euratom Treaty."

Slovenske Elektrarne, 66% owned by Italian energy group Enel and 22% by the Slovak state, wants to complete two new reactors at Mochovce by 2012 and 2013. Enel has agreed to invest Eur1.8 billion ($2.8 billion) on this project.

Under duress, as a precondition for Slovak entry into the European Union (EU) in 2004, the Slovak government committed to closing the Bohunice V1 units 1 and 2 due to perceived safety deficiencies in that early model reactor. The original date specified for closing them down was 2000, though subsequently 2006 and 2008 were agreed in relation to EU accession. Slovakia aims to complete the third and fourth units at Mochovce to compensate for the lost generating capacity from the closure of the Bohunice units.