2 October 2007
South Africa has officially opened two new peaking power stations in the Western Cape province, providing an additional 1 050 megawatts of electricity during times of high demand.
Engineering News reports this week that the open cycle gas turbine (OCGT) power plants, situated in Atlantis and Mossel Bay, were completed by the end of June at a combined cost of about R3.5-billion.
Eskom chief executive Jacob Maroga told the publication that the two plants had already been used extensively to supply demand for peak electricity during the winter.
The Ankerlig OCGT Station in Atlantis, to the north of Cape Town, has four 147-megawatt generating units in operation, while the state-owned electricity utility has applied for environmental approval to build another five generating units of similar capacity.
The Gourikwa OCGT Station in Mossel Bay consists of three 146-megawatt and is waiting for similar environmental approvals to construct an additional two generating units at the site.
The OCGT plants were also used as a backup while Eskom was refuelling a generating unit at Koeberg, South Africa’s only nuclear power plant.
According to Eskom, an OCGT plant works by igniting diesel to form a gas, which is then passed over turbines attached to motors that generate electricity. Other types of plants can directly combust natural gas to drive turbines instead of using liquid fuels.
High-voltage cables then distribute the produced electricity to wherever there is increased demand.
Also speaking at the launch, Deputy President Phumzile Mlambo-Ngcuka said increasing South Africa’s electricity generating capacity ensured that the country could give Fifa assurances about electricity supply ahead of the 2010 World Cup.
She told Business Day that Fifa wanted complete energy security because the majority of the people who would watch the matches would “not [be] in the stadium, but all over the world”.
Mlambo-Ngcuka added that the technology used on the OCGT plants enabled them to be switched between liquid fuel and gas operation, and as such South Africa was in talks with Namibia about the prospects of piping gas from offshore fields to this country.