Share

Nuclear Power in Slovakia

(Updated 25 November 2014)

  • Slovakia has four nuclear reactors generating half of its electricity and two more under construction.
  • Slovakia's first commercial nuclear power reactor began operating in 1972.
  • Government commitment to the future of nuclear energy is strong.

Electricity consumption in Slovakia has been fairly steady since 1990a. Generating capacity in 2012 was 8.2 GWe, almost one quarter of this nuclearb. In 2013, 28.5 billion kWh gross was produced, 15.7 TWh (55%) of this from nuclear power, with hydro 5.1 TWh, coal 3.3 TWh, gas 2.4 TWh and solar 0.6 TWh. Net imports were zero. Slovakia has gone from being a net exporter of electricity – of some 1 billion kWh/yr – to being a net importer following the shutdown of the Bohunice V1 reactorsc. All of the country's gas comes from Russia. Per capita electricity consumption in 2012 averaged 4430 kWh.

In November 2014 the government approved a long-term energy plan based on greater use of nuclear power, some renewables, and reducing the use of coal.

Nuclear industry development

In 1958, the Czechoslovak government started building its first nuclear power plant – a gas-cooled heavy water pressure-tube reactor at Bohunice (now in Slovakia). This 110 MWe net Bohunice A1 reactor, built by Skoda, was completed in 1972 and ran until 1977 when it was closed due an accident arising from refuellingd.

In 1972, construction of the Bohunice V1 plant commenced, with two VVER-440 V-230 reactors supplied by Atomenergoexport of Russia and Skoda. The first was grid connected in 1978, the second two years later. In 1976, construction started on two V-213 reactors (the V2 plant) built by Skoda. The V2 units commenced operation in 1984 and 1985. All were designed by Atomenergoproekt.

Despite major upgrade work on the two V1 unitse, the units were shut down at the end of 2006 (unit 1) and 2008 (unit 2) as a condition of Slovakia's accession to the European Union (see section below on EU accession). In 2013 the EU Parliament Committee on Budgetary Control complained that it was “unacceptable” that these reactors were not in irreversible shutdown.

From 2005 to 2008, operator Slovenské Elektrárne (Slovak Electric, SE) carried out a major modernization program on the two Bohunice V2 units, to improve seismic resistance, cooling systems, and instrumentation and control (I&C) systems with a view to extending operational life to 40 years (2025). This was followed by a progressive uprating program of both units1, eventually bringing the capacity of each unit from 440 gross to 505 MWe gross (472 MWe net) by November 2010. The total cost was reported to be €500 million. SE is planning to extend the licences of the V2 units to 2045 following upgrading.

In 1982, construction on the first two units of the four-unit Mochovce nuclear power plant was commenced by Skoda, using VVER-440 V-213 reactor units. Work on units 3 & 4 was started in 1986 and halted in 1992. Units 1 & 2 started up in 1998 and 1999. These two units have been significantly upgraded and the I&C systems replaced with assistance from Western companiesf. Uprates of 7% at Mochovce 1&2 were implemented by June 2008.

Construction of units 3&4 was reactivated in mid-2009 and the units were expected to commence operation in 2012 and 2013 and €2775 million was allocated to the completion project. See section below.

Bohunice V2 and Mochovce are owned and operated by SE. In 2006, Italian utility Enel acquired a 66% stake in SE. The remaining 34% is held by the state through the National Property Fund. The Nuclear Decommissioning Company, Javys, owns Bohunice A1 and V1.

Operating Slovak power reactors

Reactor Model Net MWe First power Expected
closure
Bohunice V2-1 V-213 472 1984 2024
Bohunice V2-2 V-213 472 1985 2025
Mochovce 1 V-213 436 1998  
Mochovce 2 V-213 436 1999  
Total (4)   1816 MWe  

EU accession

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 accessiong.

The latter dates were set despite major refurbishment being carried out on the units, including replacement of the emergency core cooling systems and modernizing the instrumentation and control systems. The two Bohunice V1 reactors were the first V-230 units outside the Soviet Union and had had more upgrading work on them than any other of their type, costing some US$ 300 million since 1991h. An International Atomic Energy Agency (IAEA) mission in 2000 reported that, for the V1 units, "all safety issues identified earlier by the IAEA have been appropriately addressed." Slovakia claimed that all their design safety deficiencies had been removed by the safety upgrading, and this had been confirmed by international expert safety review missions.

In the lead up to EU accession in 2004, nuclear industry representatives from Eastern Europe called for the introduction of transparent and rational EU safety standards rather than punitive closures of reactors which had been substantially upgraded. In particular, the Slovak Bohunice V1 units were cited as prime examples of the high safety standards which such reactors could achieve through upgrading with input from Western firms such as Siemens.

The units were producing electricity at half the average cost for all Slovak sources, and their closure before Mochovce units 3&4 are on line (expected in 2013 and 2014) has left the country short of power. Unit 1 of the Bohunice V1 plant was closed at the end of December 2006, eliminating about 9% of Slovakia's electricity supply. The second unit of the V1 plant was closed at the end of 2008. The Prime Minister said that he respected the decision to shut down the plant, but considered it as "energy treason" by the previous government, with Slovakia becoming an electricity importer. He suggested that it might be possible to restart the V1 units in futurei.

New nuclear capacity

In October 2004, the government approved Italian Enel's bid to acquire 66% of Slovenské Elektrárne (SE) for €840 million as part of its privatisation process. Enel's subsequent investment plan approved in 2005 involved €1.88 billion investment to increase generating capacity, including €1.6 billion for completion of Mochovce units 3&4. The estimated cost of this project has more than doubled since then.

In January 2006, the government approved a new energy strategy incorporating these plans, which includes capacity uprates at Mochovce 1&2 and the Bohunice V2 units. 

Slovak power reactors under construction, planned and proposed

Reactor Model gross MWe Construction start First power Operator
Mochovce 3 V-213+ 471 6/09 late 2016 SE
Mochovce 4 V-213+ 471 6/09 late 2017 SE
Bohunice New Block ? 1200-1750 2021? 2025? Jessk
Kecerovce ? 1200   After 2025 ?
Total under construction (2)   942  

Plans for new nuclear build were outlined in the October 2008 Energy Security Strategy of the Slovak Republic, which incorporates the nuclear power plans in the 2006 Energy Policy. The 2008 Energy Security Strategy aimed to maintain the proportion of electricity generated by nuclear power plants at around 50% through the following measures:

  • Completion of Mochovce 3&4 by 2013 (880 MWe gross).
  • Uprates at Bohunice V2 and Mochovce 1 & 2 by 2010 (180 MWe gross).
  • Uprates at Mochovce 3&4 by 2015 (60 MWe gross).
  • Construction of a new reactor block at Bohunice by 2025 (1200 MWe gross).

In addition, around 2025, when the two V2 units will have reached 40 years of operation, the strategy calls for either life extension of the V2 units or for the construction of 1200 MWe of new nuclear capacity at Kecerovce in the east of the countryl.

Mochovce 3&4

In February 2007, SE announced that it would proceed with Mochovce 3&4 completion and in July 2008, the European Commission approved the completion of the units subject to the design being brought into line with existing best practice for resistance to aircraft impactsj,3. Site works began in November 2008 and main construction activities commenced after contracts were signed in June 2009. A contract with Skoda JS, Russia's AtomStroyExport (ASE) and Slovak suppliers Výskumný Ústav Jadrovej Energetiky (VÚJE), Enseco and Inžinierske Stavby Košice was for more than €370 million to supply the remaining nuclear island equipment (beyond that delivered 20 years earlier), with part of the instrumentation and control (I&C) systems being from Siemens. Contracts for engineering, construction and project management of the conventional island were signed with ENEL Ingegneria & Innovazione, and involve the use of Skoda Power steam turbines4. Following delay due to EU stress tests, startup was planned for 2013 and 2014. Uprating is planned by 2016, adding 62 MWe total to the original 880 MWe gross. As of late 2014, 170 major design changes had been implemented, including a major one.

With the project depending substantially on the original 1986 construction permit including environmental clearance, it was challenged, and the need for a full new environmental impact assessment under European Union law was asserted5.

In December 2012 ENEL sought an extra €800 million on top of the original €2.8 billion estimate, and an extension of 22 months to complete the two units. In 2013, disagreement between ENEL and other shareholders continued, and the schedule was delayed. In August 2013 the government and ENEL agreed to release €260 million to pay suppliers, and in April 2014 the government approved a revised budget of €3.8 billion for the plant, up from €3.25 billion agreed in August 2013. Then in June 2014 the regulator said that SE’s schedule suggested that start-up would be delayed until mid-2015.

In October 2014 unit 3 was 80% complete and unit 4 60%. The design has evolved substantially from the original V-213.

Bohunice new block

The plans for a new reactor at Bohunice were announced in April 2008 for 1000-1600 MWe, probably using Western technology to enable MOX usem. In December 2008, Czech utility CEZ was announced as the 49% joint venture partner, with state-owned Javys holding 51%. CEZ reportedly paid EUR 117 million for its JV share. The formal JESS (Jadrová energetická spoločnosť Slovenska, Slovakia Nuclear Energy Company) joint venture agreement was signed in May 2009. Financing was to be finalised in 2011 and construction was planned to start in 2013, the expected cost being €3.32 billion (for a 1200 MWe unit). Following an 18-month feasibility study (due to be completed by the end of 2010) there was to be a call for tenders, Areva and Westinghouse being considered the main possibilities, and in September 2012 JESS reported that the technology offered by six vendors* met the requirements for one or two reactors at Bohunice.

* Six vendors submitted information packages in December 2010: Westinghouse AP1000, Atmea 1100, Mitsubishi APWR 1700, Atomstroyexport MIR 1200, KHNP APR 1400 and Areva EPR 1600. 

In August 2010 the newly-elected centre-right government said it was keen for the Bohunice project to proceed but would not offer any financial support for it. It was not expected to be operational before 2025, but the Minister of Economy said in May 2011 that it could be operational by 2020. A new left-wing government in April 2012 pledged to speed up the project and to decide upon proceeding early in 2013, as well as pushing completion of Mochovce 3&4, apparently delayed by the need to incorporate modifications due to EU ‘stress tests’. The November 2014 energy plan affirmed the project.

CEZ wants to sell its stake in JESS, reportedly for EUR 110 million, in order to concentrate on its Temelin project, and Rosatom has been exploring the prospect of being both technology provider and investor in this unit. In April 2013 CEZ offered its JESS share to Rosatom, and the Slovak Economy Ministry said that it would be happy to accept this change, with Rusatom Overseas buying it and building a 1200 MWe reactor from about 2021. It seeks a guaranteed long-term electricity price of EUR 60-70 /MWh, which the Economy Ministry is unwilling to provide, and possibly a BOO (build-own-operate) arrangement. Rosatom in January 2014 said it remained interested if the Slovak government could guarantee profitability in some way, and negotiations with CEZ continued.

Preliminary works on the project are proceeding. JESS has arranged for the Environmental Impact Assessment [EIA] to be undertaken by AMEC by mid-2016. Purchase of land was almost complete in 2013.

Uranium and Fuel cycle

In May 2014 Perth-based Forte Energy agreed to take over the Slovakian uranium assets of European Uranium Resources (EUU)* based in Canada through a share issue. This was not approved, so Forte agreed to pay $4 million in cash and farm-in for a 50% share in EUU subsidiaries, Ludovika Energy and Ludovika Mining, which operate in Slovakia. The cash was paid in October 2014, and Forte now needs to spend $350,000 pa over ten years to complete the deal. EUU is investigating the Kuriskova and Novoveska Huta uranium deposits as well as other uranium exploration targets in the Slovak Carpathian uranium belt in the east of the country. Kuriskova is near Kosice, and Novoveska Huta is about 50 km northwest of it, near Spisska Nova Ves. Both have potential molybdenum by-product. EUU in 2012 signed an agreement in principle with the Ministry of Economy for mining development to proceed.

* European Uranium Resources was formerly Tournigan Energy Ltd, and Areva holds 7% of the company.

In April 2011, the company announced an updated resource estimate (NI 43-101 compliant) for Kuriskova of over 12,900 tonnes U3O8 grading 0.555% U3O8 indicated resources. Inferred resources of over 5700 tonnes U3O8 grading 0.185% U3O8, were not included in the mine plan. An underground mine using conventional techniques and with a cut-off of 0.05% U was planned at a cost of US$ 225 million. Production of 530 tU/yr was envisaged from 2020. The Novoveska Huta uranium deposit has 1700 t U3O8 measured and indicated resources and 5800 t inferred resources (NI 43-101 compliant) and a mining licence.

Assessing the viability of uranium mining in Slovakia was one of the priorities of the country's 2008 Energy Security Strategy. However, in May 2014 the government resolved to ban uranium mining in the country unless it is approved by a referendum of local inhabitants, apparently due to opposition led by the mayor of Kosice. The Slovak Environment Ministry proposed the amendment to the law, which may come into effect in June.

All fuel supply is contracted from TVEL in Russia.

Radioactive waste management

Originally the policy was for used fuel to be disposed of without reprocessing, but in 2008 this changed to recycling it domestically.

At the beginning of 1996, the VYZ subsidiary of Slovenské Elektrárne was established for decommissioning nuclear facilities, radioactive waste and used fuel management. A separate subsidiary of Slovenské Elektrárne – Decom – was set up as a consultancy to focus on decommissioning. During Enel's 2006 acquisition of a 66% stake in SE, the SE-VYZ subsidiary, along with the Bohunice V1 reactors (which were in operation at the time), was transferred to the state as the Nuclear Decommissioning Company (Javys)o.

A treatment and conditioning plant for low- and intermediate-level wastes is operated by Javys at Bohunice, and a near-surface repository (the National Radioactive Waste Repository) at Mochovce began operation in 2001.

An interim wet storage facility for used fuel at Bohunice supplements reactor storage ponds, and has a capacity of 1680 tonnes (14,000 fuel assemblies). It has functioned since 1986 and is operated by Javys. Some used fuel was earlier exported to Russia for reprocessing (with Russia keeping the products).

Site selection for an underground high-level waste repository has commenced, although the country is also considering the option of participating in a shared international repository projectp.

A state fund for radwaste management and decommissioning was set up in 1995, with a levy of 10% of the wholesale price of electricity being paid into it by SE. It is expected to amount to €775 million by 2010.

Reactor decommissioning

Preparation for decommissioning the two Bohunice V1 reactors started in 2012, that work to take 13 years at an estimated cost of about €500 million. Decommissioning of the A1 reactor is underway.

 The Bohunice International Decommissioning Support Fund, administered by the European Bank of Reconstruction and Development (EBRD), was set up in 2001 to support the decommissioning of the Bohunice V1 plant, as well as to support energy projects to help minimize the impact of the early closure of the reactorsq. At the end of 2013, €225 million was made available by the EU, with support continuing to 2020.

Regulation and safety

The Nuclear Regulatory Authority of the Slovak Republic (UJDSR) is the independent regulatory body responsible for licensing, safety, waste management, radiation protection and safeguards.

Non-proliferation

The Slovak Republic is a party to the Nuclear Non-Proliferation Treaty (NPT) since 1993 as a non-nuclear weapons state. The Additional Protocol in relation to its safeguards agreements with the International Atomic Energy Agency was signed in 1999. The country is member of the Nuclear Suppliers Group, and since 2004, of Euratom.


Further Information

Notes

a. Electricity consumption in 2007 was 4550 kWh per person, up from about 4400 kWh/person in 2006. [Back]

b. Total generating capacity in 2006 was 8.2 GWe, of which 32% was nuclear. Bohunice V1-1 closed at the end of 2006, hence the drop in nuclear share of total capacity in 2007. Bohunice V1-2 closed at the end of 2008, further lowering the proportion of nuclear in the energy mix, although the planned startup of Mochovce 3 and 4 in 2012 and 2013 respectively will replace the capacity lost due to the shutdown of the Bohunice V1 plant. [Back]

c. In 2007 (the year after the closure of unit 1 of Bohunice V1), around 1.7 billion kWh net was imported. Net exports in 2006 were 2.3 billion kWh. [Back]

d. Bohunice A1 was a KS-150 reactor with natural uranium fuel, heavy water moderator and carbon dioxide coolant. It was commissioned in 1972 and ran with many unplanned outages until 1977 when an accident rated Level 4 on the International Nuclear Event Scale led to its closure. Silca gel, used as a humidity absorber, was left covering a fuel assembly during refuelling operations, resulting in core damage and fission product contamination of the primary and secondary circuits. [Back]

e. In 1996, the nuclear division of Siemens’ Power Generation Group (KWU) – which, in 2000, became part of Framatome ANP (and later Areva) – was awarded a contract for the 'gradual reconstruction of Bohunice V1', which included the installation of digital instrumentation and control systems. The REKON consortium (Siemens with Slovak engineering company Výskumný Ústav Jadrovej Energetiky, VUJE) performed the design and implementation. The modifications were mainly carried out during the outages of the units from 1998-2000. This project demonstrated that the V-230 model of VVER-440 reactors could be upgraded to international safety standards. [Back]

f. The completion of Mochovce 1&2 included an extensive program of design safety improvements involving Framatome, Siemens, and Electricité de France. The project started in 1996 and was completed in 1998 (unit 1) and 1999 (unit 2), the years in which the units began operation. [Back]

g. In September 1999, the Slovak Government adopted Resolution No. 801/99 to shut down the two Bohunice V1 units in 2006 and 2008. An earlier shutdown date of 2000 had previously been approved in September 1997 by the Slovak Government in Resolution 684/97. The adoption of Resolution 801/99 was a condition of Protocol No 9 on unit 1 and unit 2 of the Bohunice V1 nuclear power plant in Slovakia of the Accession Agreement of the Slovak Republic to the European Union. [Back]

h. Phase 1 upgrading of Bohnuice V1 was undertaken 1991-95, and phase 2 – intended to achieve Western European standards – through to 2000. In 2001, Slovakia relicensed Bohunice V1 units for another decade (until the next full safety review), though following the upgrades their operating lifetimes were expected to run until 2015. [Back]

i. Early in 2009, only a few days after the shutdown of Bohunice V2-2 at the end of 2008, a gas dispute between Russia and Ukraine affected nearly all of Slovakia's gas supplies. The Slovak government announced it had taken the decision to restart the reactor, but eventually the unit was not restarted2. [Back]

j. The European Commission (EC) said that completion of Mochovce 3&4 "fulfils the objectives of the Euratom Treaty," provided that a scenario including impact from an external source (such as a small aircraft) was developed and the necessary changes to withstand such an impact were implemented. In addition, the EC said it "remains the sole responsibility of the investor to ensure that the chosen design will provide an equivalent level of protection as a 'full containment'." It is not clear what this means, though the EC approval was simply to enable financing. The reactor's containment walls will be 1.5 metres thick and apparently the plant will be in compliance with safety requirements for existing reactors established in 2007 by the Western European Nuclear Regulators Association. [Back]

k. Jadrová energetická spoločnosť Slovenska a.s. (Jess) is joint venture between Slovak state-owned decommissioning company Javys (51%) and Czech utility CEZ (49%) established in 2009 to construct a new nuclear unit at the Bohunice site. See Slovakian nuclear JV gets government blessing, World Nuclear News (10 December 2009) [Back]

l. Kecerovce is named in the 2008 Energy Security Strategy as the site for a proposed 1200 MWe nuclear plant costing €3870 million. The plant is mainly intended to replace the nuclear capacity that will be lost when the Bohunice V2 units are shut down in 2025, depending on whether the 40-year operational lifetime of Bohunice V2 is extended. Although Kecerovce would be a new site, it had previously been considered as a potential site for a nuclear plant when Czechoslovakia was under Communist rule. [Back]

m. Bohunice, Mochovce and Kecerovce were initially considered as possible sites for the proposed new unit, before Bohunice was decided upon. [Back]

n. The Novoveska Huta uranium deposit, located approximately 65 km west of Kuriskova, was a historical uranium producer (closed in the early 1990s). Drilling completed between 1975 and 1985 reported a resource of 9000 tonnes U3O8 grading 0.075% U3O8. [Back]

o. Prior to Enel acquiring its 66% stake in Slovenské Elektrárne (SE) in April 2006, the Bohunice V1 reactors along with the decommissioning and waste management operations (under the SE-VYZ subsidiary) were transferred to the GovCo subsidiary. On Enel's acquisition of its stake in SE, GovCo was transferred to the government and later renamed as Javys (Jadrová vyraďovacia spoločnosť, Nuclear Decommissioning Company). [Back]

p. The Decom consultancy, with the Switzerland-based Association for Regional & International Underground Storage (ARIUS), ran a European Union-funded project to undertake a pilot study on the technical and legal requirements for a regional waste repository. This SAPIERR (Support Action: Pilot Initiative for European Regional Repositories) project ran from the end of 2003 for two years, and was followed by SAPIERR II, which finished in January 2009. The main proposal from the SAPIERR project was to set up a European Repository Development Organisation (ERDO). An ERDO Working Group is currently developing a consensus model for ERDO. Eight of the 14 countries that participated in the SAPIERR project are members of the ERDO Working Group (Bulgaria, Italy, Lithuania, Netherlands, Poland, Romania, Slovakia and Slovenia). See page on International Nuclear Waste Disposal Concepts [Back]

q. A webpage on the Bohunice International Decommissioning Support Fund is on the EBRD website (www.ebrd.com). [Back]

References

1. Slovenské Elektrárne Celebrates 25th Anniversary of Bohunice Unit 3, Slovenské Elektrárne press release (27 June 2009); Slovenské Elektrárne Increases Power Output at Bohunice NPP, Slovenské Elektrárne press release (23 October 2009) [Back]

2. Slovakia to restart nuclear plant, BBC News (10 January 2009); Slovak nuclear plant to restart in days?, World Nuclear News (12 January 2009) [Back]

3. Commission issues its opinion on units 3 and 4 of the Slovak Nuclear Power Plant of Mochovce, Europa press release (15 July 2008); EC requests extra safety for new Mochovce units, World Nuclear News (16 July 2008) [Back]

4. Contracts signed for completion of Mochovce, World Nuclear News (16 June 2009) [Back]

5. Outcome of the 27th meeting of the Aarhus Convention’s Compliance Committee, United Nations Economic Commission for Europe (UNECE) press release (23 March 2010) and Communication ACCC/C/2009/41 (Slovakia) webpage on UNECE website [Back]

General sources

Country Nuclear Power Profiles: Slovakia, International Atomic Energy Agency
Slovenské elektrárne website (www.seas.sk)
Javys website (www.javys.sk)
Tournigan Energy Ltd website (www.tournigan.com)
The Source Book on Soviet-Designed Nuclear Power Plants, Nuclear Energy Institute
Energy in East Europe, 3 February 2006