CEZ, a. s. - Nuclear Power Plants

• CEZ, a. s. – Nuclear Power Plants
• The fuel cycle

 

CEZ, a. s. – Nuclear Power Plants

Dukovany Nuclear Power Plant

Nuclear power plant Dukovany consists today of four 510MW units which were put into service from 1985 to 1987 and have been refurbished and enhanced later. In 2011, the installed power output of the power plant amounts 2 040 MW and represented nearly 10% of the total capacity installed within the power utility.

Fuel for Dukovany Nuclear Power Station is sourced under a long-term contract with Russia-based OAO TVEL, which not only fabricates the fuel, but also provides conversion and enrichment services as well as some of the base raw material (uranium). In 2011, only the improved, latest version of the VVER 440 second-generation fuel was supplied.

Selected Events of 2011:

• June 2011, EMANI held a periodic risk inspection, which ended with an identical, positive conclusion as in the case of Dukovany Nuclear Power Station. Other inspections focused on occupational safety and health and protection of the environment.emelín Nuclear Power Plant.
• At Dukovany Nuclear Power Station, planned repairs will take place on Units 1, 2, and 4 in the standard scope, combined with partial fuel replacement. On Unit 2, an extended-scope repair will be carried out with the aim of increasing achievable capacity to 500 MW.

Temelín Nuclear Power Plant

Two production units with 1,000 MW of power output capacity. The Skoda Praha Company assumes the role of chief supplier.

Selected Events of 2011:

• Up until a fuel replacement in Temelín Nuclear Power Station, 2011 saw continued operation with modified fuel fromWestinghouse Electric Company LLC (USA) on Unit 2 (fuel with a reinforced structural skeleton and utilizing the modern ZIRLOTM alloy.
• October - Request For Proposal (RFP) documentation distributed to qualified bidders in the RFP proceedings for the public procurement tender Completion of Temelín Nuclear Power Station. Deadline for submission of bids is
  July 2, 2012.

 

Nuclear Power Plants	Installed power output	Year of commission
Dukovany	4 x 510	1985 - 1988
Temelín	2 x 1,000	Unit 1 - 2002 Unit 2 - 2003

 

The fuel cycle

In 2011, over 87.5 TWh of electrical power was produced in the Czech Republic, of which CEZ, a. s. produced more than 72% (63 TWh).

The nuclear energy industry cover more than 40% of electrical power consumption in the Czech Republic.

The Dukovany Nuclear Power Plant has four 510 MW units with VVER 440/213 pressurised water reactors. The particular units were commissioned in the period from 1985 – 1987. In the Temelín Nuclear Power Plant there are two 1,000 MW units with VVER 1000 pressurised water reactors installed. As far as the power output is concerned, nuclear power plants occupy leading positions in the list of Czech Republic power plants.

The fuel of both Czech nuclear power plants is uranium dioxide UO₂, where uranium is slightly enriched with the 235 fissile isotope (for 2-4% of the uranium total amount; there is only 0.7% of 235 isotope in natural uranium).

The atomic act passed by the Czech Parliament in 1997 requires that all radioactive waste originators, and therefore CEZ, a. s. as well, bear the costs associated with radioactive waste depositing after its origination, with safety and security measures concerning the deposits included. The guarantees for a safe deposit of all the radioactive waste, including spent nuclear fuel, are provided by the state, which established the Radioactive Waste Deposit Management Office (SURAO), in order to comply with the requirements stipulated in the law.

Activities provided by SURAO are financed from the nuclear account. All radioactive waste originators contribute to the account. CEZ, a.s. contributes an amount in proportion to the energy quantity produced from nuclear power plants. This amount represents approximately 5% of the electrical power acceptance price. CEZ, a. s. generates a separate accounting provision to cover the costs associated with power plant decommissioning after the end of their operation.

The Dukovany Nuclear Power Plant produces less than 44 tons of spent nuclear fuel annually. Both nuclear power plants will produce 3,000 tons of spent nuclear fuel during their entire operation periods. The spent nuclear fuel produced by Dukovany NPP was initially transported into an intermediate storage facility situated in the Jaslovske Bohunice NPP area in Slovakia, from where it was expected to be gradually removed on the basis of an international treaty concluded with the (former) Soviet Union. The Russian Federation, however, as one of the successor states of the Soviet Union withdrew from these obligations. Following the split of Czechoslovakia, spent nuclear fuel from Dukovany NPP suddenly appeared on the territory of a foreign state whereby the Czech Republic accepted a return transport of the fuel assemblies into its own intermediate storage facility built in the Dukovany NPP area. The intermediate dry storage facility, with its 600 tons of spent nuclear fuel capacity, comprises 60 dual-purpose (transport and storage) Castor 440/84 delivered by GNS Nukem, a German supplier.

In 2005, the existing storage capacity of the Dukovany spent nuclear fuel intermediary storage capacity shall be used up. Therefore, design works have started on an extension of the storage capacity. The spent nuclear fuel from Temelín NPP shall be stored in a storage facility situated within its area and its construction is envisaged in the near future. Concurrently, CEZ a. s. continues with a collection of background information for the design of a storage facility situated outside of the nuclear power plant area. A central deposit for spent nuclear fuel is projected to be constructed in the “Skalka” location near the Zdar nad Sazavou district. This project is being prepared as a backup in case the next construction of storage capacities may not be implemented in the area of the nuclear power plants for some reason. The technical solution envisaged for all options of spent nuclear fuel storage, i.e. both construction and operation of a dry storage facility, is very progressive and in line with world standards.

The spent nuclear fuel shall be placed into the storage facility for the period of a few dozens of years. Its temperature shall drop to a level at which it could then be deposited into a final deep depository, where further supervision would not be necessary. As previously stated, works related to the final storage of spent nuclear fuel are ensured by the Radioactive Waste Storage Management Office (SURAO).

Additionally, CEZ, a. s. is monitoring options of spent fuel recycling before its final deposition. As a long-range option for spent nuclear fuel energy utilisation, there are ADTT procedures available, i.e. accelerator-driven transmutation technologies. These are technologies orientated towards utilisation of the enormous nuclear power potentials, which the present types of reactors cannot release from the fuel, as well as towards nuclear transmutations of long life-span radionuclides to make the period when waste is dangerous due to radioactivity substantially shorter.