Eskom’s coal-fired power stations are the mainstay of the South African economy and 93% of the country’s electricity production needs are met by coal, reports Creamer Media’s Research Channel Africa.

However, these power stations pump millions of tons of carbon dioxide (CO₂) into the atmosphere and are one of reasons why South Africa is the largest contributor to greenhouse-gas emissions in Africa.

As a result, the report states that South Africa is now at the forefront of research into so-called clean coal technologies (CCTs), aimed at reducing the huge volumes of greenhouse gases emitted by its power stations.

Clean Coal Technologies
Creamer Media’s Research Channel Africa reports that South Africa’s remaining coal reserves are generally of a lower quality than the coal that has been mined over the last three decades. CCTs have the potential to improve this coal, and uses large quantities of discard coal for economic and energy purposes through beneficiation.

One of the other CCTs being pursued is fluidised bed combustion, which can meet stringent nitrogen oxide (NOx) and sulphur dioxide (SOx) emission regulations. Through the rapid mixing of a bed of ash, pulverised coal and limestone can ultimately lead to the complete combustion of the fuel.

Another new development in CCTs is underground gasification, whereby coal is burned in the seam. The report states that this technology can be applied to high-ash, thin-seam and deep-seated coals that may not otherwise be commercially viable to mine. The gas produced through this process may be used for power generation, as well as the production of petrochemicals.

In addition, carbon capture and storage (CCS) involves preventing CO2 produced through combustion from entering the atmosphere by storing it underground in deep-seated porous rock strata, either on land or similar strata under the sea bed.

The report states that this is not yet a viable option in South Africa, as the country does not have much in the way of suit- able subterranean strata on land to store the excess CO₂.

Greenhouse-Gas Emissions
Meanwhile, the report states that reducing greenhouse-gas emissions and the development of clean coal technologies have become important economic and political issues.

But new European Union (EU) environmental regulations, which took effect in January 2008, could potentially hurt South African coal exports to the EU.

The report states that, while South African export coal has a low sulphur content, it produces higher NOx emissions than coal mined in Indonesia and Colombia when heated in traditional boilers.

There are fears that the EU’s Large Com-bustion Plant Directive (LCPD) will force European consumers of coal to source their coal requirements from countries producing coal with low NOx emissions, the report states.

However, there is a growing awareness and acceptance in the EU of the importance of reducing and limiting the harmful emissions associated with coal-fired power generation.

To this end, the EU is investigating CCTs and is proposing to launch 12 CSS demonstration projects by 2015, the report states. It has been suggested that the EU mandate that all new coal-fired power stations be built with CCS facilities by 2020.

Creamer Media’s Research Channel Africa reports that it may be possible for South Africa to participate in one of the EU’s 12 proposed CCT demonstration plants. As the world’s biggest generator of coal-fired power, it makes environmental and political sense for South Africa to take a leading position in the clean-coal drive.