Koeberg Nuclear Power Station
Koeberg Nuclear Power Station is a nuclear power station in South Africa and the only one on the entire African continent. It is located 30 km north of Cape Town, near Melkbosstrand on the west coast of South Africa. It is owned and operated by the country's state-owned electricity public utility, Eskom.
Design[edit]
Koeberg contains two pressurised water reactors based on a design by Framatome of France. Framatome has a 51% shareholding in local South African company Lesedi Nuclear Services which performs upgrade and maintenance projects at Koeberg.[1] 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. Fuel stock used within the reactor is enriched uranium dioxide pellets containing gadolinium, contained in fuel rods.[2] Koeberg is rated at 1,860 MW, its average annual production is 13,668 GWh and it has two large turbine generators (2 × 970 MW).[3][4]
Each reactor delivers 970 MW (gross) and is capable of delivering 930 MW (net) to the grid.[5]
The power station was constructed near Cape Town to be the sole provider of power in 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 was too small to provide Cape Town's needs, and the Paarden Island power station (itself too small) has been demolished.
Koeberg was one of the first nuclear power stations designed to be specifically resistant to earthquakes. The reactors at the Koeberg nuclear power station are built upon an aseismic raft designed – on the basis of a mid-1970s hazard study - to withstand a magnitude 7 earthquake at a focal distance of about 10 km, 0.3g zero period ground acceleration (ZPGA). The largest recorded earthquake in the Cape Town area has been 6.5 magnitude at Jan Biesjes Kraal in 1809.[6][7][8]
The reactor at Koeberg is cooled by cold water from the Atlantic Ocean pumped through an isolated circuit at 80 tons a second.[9] 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 power station was originally located outside the metropolitan area, but urban growth has exceeded expectations in the intervening years, so that the power station is now close to suburban housing. The administration enforces maximum housing density regulations in case of evacuation, which precludes the construction of high rise buildings. The buffer zone around the nuclear power station forms the 22 km2 Koeberg Nature Reserve, open to the public and containing more than 210 species of birds and a number of mammal species including zebra, eland and springbok.[10]
Post Fukushima stress tests[edit]
After the Fukushima Daiichi nuclear disaster, seismic safety at Koeberg was reevaluated in conjunction with the IAEA. Although Koeberg was designed for 0.3g zero period ground acceleration (ZPGA), a magnitude 7 earthquake, stress tests evaluated Koeberg against a 0.5g ZPGA. Overall Koeberg found to be seismically robust and well designed, with some areas for attention and improvement that were highlighted.[24]
Opposition to Koeberg[edit]
South Africa's nuclear industry has seen its fair share of opposition, chiefly from environmentalists concerned about 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. [26][27] [28]