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Eskom, as a state-owned enterprise, has a greater role to play in addition to the supply of electricity. As a good corporate citizen we support South Africa’s growth and development aspirations as well as its sustainability concerns. Refer here for how we see our role in South Africa and here for our governance processes in this regard.

The impact of the power disruptions last year was profound. It touched the lives of every South African in some way or another, and had an impact on confidence in the country and its image abroad.

At the beginning of this financial year the power system was still vulnerable, largely due to the inadequacy of the reserve margin1. The problem was exacerbated by low coal reserves at our power stations, as well as quality-related issues. The heavy rains in January and February 2008 made the handling of coal a near impossibility at some stations.

A year later the status of the electricity system has changed dramatically. A decrease in demand together with the technical recovery of the Eskom power system brought about a much healthier reserve margin, moving from around 5% in January 2008 to about 14% this January (including imports).

Coal stockpile days for the system were taken from an average of 12 days in January 2008 to an average of around 41 days, with every power station having stockpile levels above 20 days. There are still issues with the quality of coal, but collaboration with the collieries has improved dramatically. The stations vulnerable to rain have stockpiles of about five days of coarse coal treated with chemicals to resist moisture filtering in. This strategy proved successful at most stations in January 2009 with limited coal-related load losses at these sites despite very high rainfall.

Since the launch of the technical recovery actions in February 2008, a significant improvement in technical performance has been achieved. The generation plant performance was stabilised by winter 2008 and the required level of plant availability and reliability achieved to meet customers’ electricity demands.

While the principles and lessons learned through the recovery initiative are being progressively applied to all other plant areas, the focus now moves to achieving a sustainable performance level within an environment of severe financial constraints.

Transmission’s 2008/9 interruption performance shows a significant improvement compared to the 2007/8 performance. Of the three major incidents recorded, two were the result of problems with the gas-insulated switchgear at the Invubu substation, while the third related to load shedding.


The Distribution availability index is marginally worse than the previous year, but the interruption duration and frequency index has improved. The impact of planned interruptions was reduced due to better outage coordination and increased utilisation of live line techniques.

However, the constraints on Eskom’s energy supply will continue until new power stations start coming online in 2012. In the mean time, the Eskom demand-side management (DSM) initiative aims to reduce national energy demand by 3 000MW by March 2011 and a further 5 000MW by March 2026. This, among others, involves the installation of energy efficient technologies to alter the load profile of Eskom. Since the inception of DSM in 2003 up to end March 2009, a total cumulative saving of 1 999MW has been achieved.

The Eskom build programme is on track to deliver the projects as planned. Over the five years to March 2013, Eskom will spend R385 billion in nominal terms on capacity expansion. South Africa needs to build 40 000MW of new generation capacity by 2025, of which 12 476MW are already under construction (mainly Medupi and Kusile power stations, return to service stations and Ingula power station). Since the programme began in 2005, we have already commissioned 4 454MW. A further 6 184MW will come on stream within the next five years (which includes the 2009 calendar year). This includes the completion of the two remaining old coal-fired stations being returned to service, the upgrade of Arnot power station and the first three units of Medupi and the first unit of Kusile.

Some 1 962km of high-voltage transmission lines have been built in the past four years, as well as numerous new transmission substations and transmission network upgrade projects. The construction of the 765kV ultra high-voltage line to the Cape is progressing well, with 430km already strung. The Apollo substation refurbishment was completed in May 2008. This increases the availability of the Cahora Bassa/Apollo high-voltage direct current interconnection.

1. A cushion of spare capacity that can be used when planned maintenance is necessary and when the system is impacted by unexpected technical faults that demand unplanned maintenance, such as poor coal quality, sudden peaks in demand, or “acts of God”, such as extreme weather conditions. Reserve margin is measured as a percentage of maximum generating capacity.
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