Koeberg nuclear power station

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Coordinates: 33°40′36.73″S, 18°25′52.28″E

Koeberg nuclear power station gets its name from the small mountain Koeberg (pronounced: Kooburg) and is located 30 km north of Cape Town and the suburb of Melkbosstrand on the West coast of South Africa.

1 Design
2 1982 interruption
3 2002 Greenpeace action against Koeberg
4 2005 interruptions
- 4.1 Loose bolt
5 2006 interruptions
6 Opposition to Koeberg
7 References
8 See also
9 Sources

[edit] Design

Koeberg nuclear power station contains two uranium pressurized water reactors based on a design by Framatome of France. It is operated by the national power utility, Eskom.

Koeberg houses South Africa's only commercial nuclear reactors. The only other two reactors were built for nuclear research purposes at Pelindaba near Pretoria. Koeberg supplies power to the national grid so that over-capacity can be redistributed to the rest of the country on an as-needed basis. Koeberg is rated at 1800 MW, its average annual production is 13,668 GWh [1] and it has the largest turbine generators (2 × 900 MW) in the Southern Hemisphere.

The plant was constructed near Cape Town to be the sole provider of power to the Western Cape after fossil fuel power stations were deemed too small and too expensive to be viable. Nuclear power was considered because it was more economical than transporting coal to the existing fossil-fuel power stations; and construction of new fossil-fuel power-stations, which would have required 300 m tall chimneys to comply with clean-air legislation. Athlone Power Station in the city is too small to provide the needs of the City Of Cape Town, and the Paarden Island Power Station (itself too small) has been demolished.

The reactor at Koeberg is cooled by means of cold water from the Atlantic Ocean and pumped through an isolated circuit.

The plant has been in more or less continuous operation since it was commissioned. Construction began in 1976 and Unit 1 was synchronised to the grid on 4 April 1984, and Unit 2 followed on 25 July 1985. There have been no serious radiation incidents.

Low and intermediate level waste from Koeberg is transported by road in steel and concrete containers to a rural disposal site at Vaalputs, 600 km away in the Kalahari Desert.

The grounds of the nuclear plant form a 22 km² nature reserve open to the public containing more than 150 species of birds and half a dozen small mammal species.

The power plant was originally located outside the metropolitan area, whose growth has far-exceeded expectations in the intervening 20 years, so that the power plant is now close to suburban housing. The plant administration enforces maximum housing density regulations in case of evacuation, which precludes the construction of high rise buildings.

[edit] 1982 interruption

On the 70th anniversary of the formation of the ANC, on January 8, 1982, Umkhonto we Sizwe, the armed wing of the ANC attacked Koeberg nuclear power plant, by firing SAM 7 missiles into the enclosure, causing extensive damage. [2]

[edit] 2002 Greenpeace action against Koeberg

In August 2002 Greenpeace the international environmental organisation, hung an anti-nuclear protest banner from the power plant, resulting in 12 members being arrested and fined. [3]

[edit] 2005 interruptions

At the end of 2005, Koeberg started experiencing numerous technical difficulties. On 11 November 2005, a fault on a transmission busbar caused the reactor to go into safe mode, cutting supply to most of the Western Cape for about two hours. On 16 November a fire under a 400kV transmission line caused the line to trip, causing severe voltage dips which resulted in Koeberg once again shutting down. Various parts of the Cape were left without electricity for hours at a time. On the evening of 23 November, a routine inspection of the backup safety system revealed a below-spec concentration of an important chemical, resulting in a controlled shutdown of the reactor. Due to the sufficiency of backup supply, major power cuts were not experienced until Friday 25 November, when the backup capacity began running out. At this point, rotational load shedding was employed, with customers being switched off in stages for most of the day. Koeberg was eventually re-synchronised to the national grid on Saturday 18 November.

[edit] Loose bolt

On Sunday 25 December 2005, the generator of Unit 1 was damaged. While the generator was being powered up after scheduled refueling and maintenance, a loose bolt which was left inside the generator caused severe damage, forcing it to be shut down. Repairs were initially estimated to take at least three months, and as of March 2006, were not yet complete. A replacement rotor, weighing 200 tons, is to be shipped in from France. Unit 1 was brought back into operation in May 2006.

While the repaired Unit 1 has been synchronized back into the grid, Unit 2 has been taken offline for scheduled maintenance and refueling. Since then, the Western Cape has been again subjected to load shedding. Unit 2 is scheduled to be offline for around 60 days.

[edit] 2006 interruptions

Large parts of the Western Cape Province experienced black-outs on Saturday 18 February 2006 and Sunday 19 February 2006 due to a controlled shutdown in accordance with operating procedures. According to Eskom and the City of Cape Town, power cuts were to continue until 26 February 2006, however power supply problems have continued past this date.

The estimated economic losses due to the power cuts is over R500 million, and this could rise to up to R2 billion. Capetonians have been buying gas cookers and petrol generators to supplement the lack of electricity.

As of 4 March 2006, the major causes of these power failures now seem to be:

Due to unprecedented population growth and regional development in the province since 1994, the current electricity demand of 900MW almost equals the capacity of one of Koeberg's turbines.
Only a single set of power lines of sufficient capacity connects the province to the national power grid as a backup source of electricity in the case of a total shut-down of the power plant.
Technical problems at Koeberg as detailed above.

[edit] Opposition to Koeberg

South Africa's fledgling nuclear industry has seen its fair share of opposition, chiefly from environmentalists concerned about post-Chernobyl safety issues such as radioactive waste, and anti-war activists concerned about nuclear proliferation and use of atomic weapons. Current campaigns against nuclear energy are being run by Earthlife Africa and Koeberg Alert.