S African power shortages set to continue

 residential water meter South Africa’s current power supply shortage is likely to leave the country vulnerable for a number of years going forward, with some even suggesting that the situation could persist for the next five to eight years if appropriate and immediate interventions are not made. Until recently, South Africa had excess electricity generating capa- city, owing to a period of overinvest- ment by Eskom. However, this situation has come to an end, and the country is now in a position where it needs to commission additional plants urgently. Already power outages are common. Between December 2005 and May 2006, a number of power outages were experienced in the country, in the Western Cape, following damage to one of the reactors at the province’s only power station. Then in early 2007, outages were experi-enced across the country, when higher-than-expected summer demand coincided with unplanned outages and the closure of several power stations for maintenance. From October 2007 until the end of the year, the country was hit by repeated load-shedding and rolling blackouts, and in January 2008, the crisis reached a new level, with daily load-shedding events. At that point, the South African government released a press statement indicating that it was the view of Cabinet that the unprecedented unplanned power outages must be treated as a “national electricity emergency that has to be addressed with urgent, vigorous and coordi- nated actions commensurate with such an emergency situation”. Although the situation has since been stabilised to some extent, the risk of load-shedding remains and interventions will be necessary to remedy the problem. South Africa’s surplus electricity capacity is now depleted, and Eskom’s reserve margin – the spare power plant capacity available when the highest demand of the year is recorded – has fallen to between 5% and 10%. A more acceptable margin would be between 15% and 20%, which would allow time for maintenance throughout the year as well as for power plant to be operated at levels where equipment is not highly stressed. In the current situation, opportunities for the maintenance and refurbishment of existing facilities have become limited, and any unplanned outages of generation capacity result in power interruptions and load-shedding. Of course, the limited maintenance and refurbishment activities taking place at existing facilities, and the fact that plants are being run harder than ever before to meet demand, means that unplanned breakdowns are more likely. Load-shedding is a last-resort measure, undertaken in order to maintain the stability of the grid and prevent a systemwide blackout, which could take days, or even weeks, to restore. Measures implemented prior to load-shedding include the running of all available generation at its maximum rating; demand market participation, where customers are paid to reduce their load; the use of gas-fired facilities, which are expensive to operate; the use of emergency pumped-storage resources; and the interruption of load to certain customers, as outlined in their supply contracts. In addition to the problems being faced as a result of generation capa- city shortages, some key transmission corridors in the country are constrained, and the distribution sector is in a state of disarray owing to an extended period of policy uncertainty and inadequate maintenance. It is believed that these sectors also pose a significant threat to the country’s security of electricity supply.