Temelín Nuclear Power Station

History

Planning began in the late 1970s and the final project was submitted in 1985. Construction of four operating units began in 1987. The project was expected to be completed in 1991 with estimated building costs of 35 billion Kčs. Six villages were demolished by the then-Communist government to make way for the power station.

After the Velvet revolution in 1990 the Czechoslovakian government decided to cease construction of the third and fourth reactors. Work continued on the first two reactors; in the 1990s alterations to the original design were made by Westinghouse in conjunction with SUJB and the IAEA to bring reliability and safety levels into conformance with Western European standards. The standards audit was carried out by Halliburton NUS. As part of the alterations information and control systems were added, electrical modifications carried out, and cabling, reactor core and fuel elements were replaced. In 1993 the Czech government decided to complete the plant in the face of delays and cost overruns, with expected completion at the time estimated for 1997. In 1994 an opinion poll reported that 68% of Czech citizens were in favor of nuclear power development.

In 1998 construction still was not completed and costs reached 71 CZK billion. The Czech government again reconsidered completion of the plant. In 1999 the decision was made to continue, hoping for an expected completion in 2000 with a maximum cost of 98.6 CZK billion. The project was controversial; national and international (mainly Austrian) opposition was stronger than in the early 1990s. In a 1999 opinion poll 47% of Czech citizens were in favor and 53% against nuclear power development.

As early as 1993 there were local and international protests against the plant's construction. Large grassroots civil disobedience actions took place in 1996 and 1997. These were organized by the so-called Clean Energy Brigades. In September and October 2000, Austrian anti-nuclear protesters demonstrated against the Temelin Nuclear Power Plant and at one stage temporarily blocked all 26 border crossings between Austria and the Czech Republic. The first reactor was finally commissioned in 2000 and the second in 2002.

Technical data

Most information were taken from ČEZ website Others from leaflet "Energy from South Bohemia" by ČEZ Group and the IAEA PRIS database. In 2013 the reactors were uprated to 1003 MWe net, and 1056 MWe gross.

The reactor vessel (active zone)

The reactor contains 163 fuel assemblies.
A single assembly has the shape of ~4.5m long hexagonal and inside are 312 fuel rods and 61 control rods.
The fuel rods contain stacked cylindrical fuel pellets.
Fuel enrichment: max. 4% (average 3.5%) of ²³⁵U (fissile isotope)
Fuel load UO₂: 92t (The reactor splits about 3 kg of uranium every day)
Fuel Replacement cycle: 4 years (every year 1/4 is changed)
vessel height: ~11m, outside diameter: ~4.5m, wall thickness: 193mm
The vessel is designed for up to 17.6MPa at 350 °C
The vessel is made of high quality, low-alloy chrome-nickel-molybdenum-vanadium steel

For the reactor to produce thermal output 1W, 30 billion fissions of uranium-235 must take place every second. For a coal power station to produce the same output 1,500,000,000 billion carbon atoms must be burned.

Reactor cooling system

Number of cooling loops: 4
Quantity of primary circuit coolant: 337 m³
Operating pressure: 15.7MPa
Coolant inlet temperature: approx. 290 °C (554F)
Coolant outlet temperature: approx. 320 °C (608F)
Coolant flow through reactor: 23.5 m³/s

Steam generator

Number per reactor block: 4
Steam delivered per one generator: 1470 t/hour
Steam outlet pressure: 6.3MPa
Steam outlet temperature: 278.5 °C (533.3F)

Cooling circuit

The plant has 4 cooling towers (each reactor has 2 towers). Each tower has a height of 150 metres (490 ft), a diameter of 130 metres (430 ft), and an external wall surface area of 44,000 square metres (470,000 sq ft). Pure water is evaporated in cooling tower (~0.3m³/s). The water needs to be constantly refilled.

Protective Envelope (containment)

Height of cylindrical section: 38m
Inside diameter of cylindrical section: 45m
Wall thickness: 1.2m
Thickness of steel lining: 8mm

Turbine generator set

Number per production block: 1
Number of steam turbine sections: 1 high pressure + 3 low pressure
Speed: 3000 rpm
Voltage on alternator's terminal: 24KV
Alternator cooling: hydrogen – water

Reliability

The International Atomic Energy Agency data show that Reactor 1 reaches a cumulative operating factor of about 63%, and Reactor 2 an operating factor of about 76%. The cumulative operating factor figures for Temelín NPP reactors are lower than the figures of similar reactors operated in Russia, where the cumulative operating factor is around 80-87%. ČEZ had increased operating factor and production in recent years and the plant reached 84% in 2012 with a total record production of 15 TWh.

New reactors

Plans to build all four original reactors were reopened in 2005. However, in 2014 the prospective plans were cancelled.

In 2007 planning was suspended because a new government agreed not to promote nuclear energy; a Green Party was a member of the coalition government. However, in July 2008 ČEZ requested the Ministry of the Environment conduct an environmental impact assessment for two additional reactors. In 2009 regional approval was granted for the new build. In August 2009, ČEZ sought bids for two pressurized water reactors (PWRs). Shortly after the Fukushima nuclear accidents, Prime Minister Petr Nečas announced that the construction of new reactors will continue according to the original plans, but with the tender selection delayed to 2013.

In July 2012 ČEZ opened bids for the public contract for completing the Temelín Nuclear Power Plant in the presence of the bidders’ - Areva, a consortium of the Westinghouse Electric Company, LLC and WESTINGHOUSE ELECTRIC ČR, and a consortium of ŠKODA JS, Atomstroyexport, and Gidropress. In October 2012 ČEZ informed Areva that they have in their bid failed to meet statutory requirements for building two new units of the Temelín Nuclear Power Plant. Moreover, Areva has not fulfilled some other crucial criteria defined in the tender. Since the award procedure has been conducted in accordance with the Public Procurement Act, Areva’s bid had to be excluded from further evaluation.

In March 2013, a Russian led consortium, comprising Atomstroyexport, Gidropress and Skoda, signed contracts with the three Czech companies ZAT, HOCHTIEF CZ and UJV Rez, for the construction of the two new nuclear reactor units for Temelín-3 and Temelín-4. The reactors proposed are the MIR-1200 (Modernised International Reactor). ZAT would supply automated systems for the plant, HOCHTIEF CZ would be responsible for construction of the nuclear island, and UJV Rez would help compile project documentation for the nuclear and turbine islands, and also create working documentation for construction of the plant. A statement said the consortium is aiming for a “localisation level” of 75 percent. The other running project for the contract was Westinghouse with its AP1000 reactor. The winner of the contract was scheduled to be announced at the end of 2013.

In April 2014, ČEZ cancelled the project after the Czech government stated it does not plan to provide guarantees or other mechanisms to support the construction of low-emission power plants following discussions in the EU. The ČEZ CEO stated:

While originally the project was fully economically feasible given the market price of electricity and other factors, today all investments into power plants, which revenues depend on sales of electricity in the free market, are threatened.