Slovakia’s nuclear regulator, the Office for the Supervision of Nuclear Power Plants (ÚJD) on 13 May issued a permit for the commissioning of unit 3 of the Mochovce NPP. UJD said that after verifying compliance with all technical and legislative requirements, it had issued a permit for the commissioning of Mochovce 3, as well as related permits for radioactive waste and used fuel management and early use buildings. Since plant owner/operator Slovenske Elektrarne (SE) applied for the permit in December 2016, ÚJD said it had thoroughly inspected and evaluated all areas proving the technical and qualitative readiness of unit 3 for the introduction of fuel.
Issue of the permits was preceded by extensive inspection, control and analysis by UJD inspectors and their external support, which was much more extensive than on previous occasions. “Given the nature of the activity that was the subject of the permitting process, and also to support participation of domestic and foreign public in the decision-making process, UJD SR continuously detailed the individual steps in the proceedings on its website, where it also published documents relating to the decision and proposals,” the regulator noted. Following announcement of the decision by public decree there will be a period for consultation before fuel loading can begin.
Construction of the Mohovce NPP began in 1982, and the first two units (VVER-440s) were commissioned in 1998 and 1999. Construction of the second phase of the plant (Mochovce 3&4, also VVER-440s) started in 1986, but was frozen in 1992 in the wake of the Soviet collapse. Work resumed in 2009 but was suspended again after the 2011 Fukushima accident for upgrading to comply with new safety requirements. In 2009, the aim was to have both units in operation by 2013, at a total cost of €2.8 billion ($3.4bn). This estimate was increased in early December to about €6.2 billion.
Unit 4 is scheduled for commissioning in 2022.
The two new units at Mochovce are expected to cover about a quarter of Slovak energy demands. Commissioning of unit 3 will allow Slovakia reach energy self-sufficiency for the first time since 2007, SE said in a statement. SE CEO Branislav Strýček said on 13 May: "Today, the third unit is fully technically ready and we will start introducing fuel into the reactor immediately after the permit comes into force." The Slovak state owns 34% of SE, while Slovak Power Holding, a joint venture between Italy’s Enel and Czech energy group EPH, owns the remainder. EPH has the option to buy out Enel once Mochovce 3&4 are complete.
SE noted that verification of the readiness of unit 3 for operation had also included two international inspections, including an International Atomic Energy Agency (Pre-OSART mission) and a World Association of Nuclear Power Plant Operators (WANO mission), which were attended by several dozen international experts. “The missions did not find any obstacles that would prevent the commissioning of the third unit and the subsequent safe and reliable operation in the coming years,” SE said. While the exact date of introduction of fuel into the reactor depends on the entry into force of the permit, the nuclear fuel for the reactor is ready in the fresh fuel storage facility.
"Our top priority when putting the unit into operation is safety, and this is how we will approach the next phase of physical and energy start-up. We have decades of experience in the operation of nuclear units and a very capable team of Slovak experts who will have the whole process under full control. " Approximately 450 suppliers took part in the completion. At the time of the peak of construction, almost 7,000 people worked on the Mochovce 3 and 4 construction sites, working more than 103 million man-hours so far.