The state-owned power utility, Eskom, generates about ninety five percent of the electricity produced in South Africa. Plans by the government of South Africa in the mid-nineteen nineties to restructure the electricity industry in the country prevented Eskom from embarking on capacity expansion activities when it was necessary. Load growth, as a result of economic growth and a national electrification programme, caused an erosion of the electricity reserve margin, which was quite massive in the early nineties. The large reserve margin then caused Eskom to reduce operating capacity by mothballing some generating plants and putting them in reserve storage.
The current situation is that the reserve margin has dropped to about 17,4 percent and a capacity expansion programme is underway. Though the apparent reserve margin is within the desired range, plant unavailability has diminished the reserve margin in real terms and this does not leave Eskom with much room for planned maintenance and a buffer to manage unplanned maintenance, the result being that plant incidents and technical problems cannot easily be absorbed within the power system to avoid interruption of supply. Also, the new environmental legislation does not help the situation, as it has the potential to shut down generating plants that do not meet the new emissions standard. In addition, there have been problems with the New Build Programme that caused a delay, of over three years, in the delivery of new power, and to compound the problem the Energy Regulator refused recently Eskom’s application for additional tariff increase, which was requested to enable the company provide the finances to cover the shortfall in funding for operational expenses and the New Build Programme. As such, Eskom faces many challenges in meeting its obligation to South Africa, and interventions are in place to manage the situation. In the short term, the key to generation sustainability is improved plant health, brought about by on-time maintenance and correctly-scoped and no-slip outages.
This paper presents an overview of the power situation in South Africa, explaining where the country has come from, the plan for long term security of supply, and the challenges faced by Eskom from the generation supply side in meeting the demand load in the short term. Trends in the performance indices indicative of plant health are examined and it is argued that executing planned plant maintenance will improve plant health and, hence, plant availability, which can bring about a turnaround in the short term power supply situation, as Eskom awaits new capacity from the New Build Programme.