Internationally, coal is currently the most widely used primary fuel, accounting for approximately 36% of the world's electricity production. This situation is likely to remain until at least 2020.
Coal has traditionally dominated the energy supply sector in South Africa, from as early as 1880 when coal from the Vereeniging area was supplied to the Kimberly diamond fields. Presently, about 77% of our country's primary energy needs are provided by coal. This is unlikely to change significantly in the next decade, due to the relative lack of suitable alternatives to coal as an energy source.
South Africa produces an average of 224 million tones of marketable coal annually, making it the fifth largest coal producing country in the world. 25% of our production is exported internationally, making South Africa the third largest coal exporting country. The remainder of South Africa's coal production feeds the various local industries, with 53% used for electricity generation. The key role played by our coal reserves in the economy is illustrated by the fact that Eskom is the 7th largest electricity generator in the world, and Sasol the largest coal-to-chemicals producer.
South Africa's coal reserves are estimated at 53 billion tonnes, and with our present production rate there should be almost 200 years of coal supply left.
Producing electricity from coal starts when the coal is pulverised in huge mills into a fine powder before it is blown into huge kettles, called boilers. Due to the heat in the boiler, the coal particles combust and burn to generate heat to turn water into steam. The steam from the boilers is used to turn the blades of a giant fan or propeller, called a turbine. The turbine turns a coil made of copper wire (the rotor) inside a magnet (the stator). Together they make up the generator. The generator produces an electric current, which is sent to the homes and factories of consumers via power lines.
- SA has abundant coal reserves.
- Coal-fired power stations are reliable.
- South Africa's infrastructure to generate electricity from coal is well established.
- Burning coal is the most cost-effective and energy efficient way of generating electricity.
- Coal has the most waste problems of all energy sources. Waste includes sulphur and nitrogen oxides, organic compounds, heavy metals, radioactive elements, greenhouse gases and a lot of ash.
- Building a coal-fired power station is a long and expensive process.
- South Africa's coal fields are concentrated in Mpumalanga, which limits the location options for power stations.