Assessing the Costs and Risks of the South African Electricity Portfolio: A Portfolio Theory Approach

Portfolio theory is used to evaluate the cost and risk of the South African electricity generation portfolio in a bid to find out how were the costs and risks of the South African electricity generation portfolio managed following the 2007 and 2008 load shedding events. The costs considered are fuel, environmental levy and operating and maintenance costs, for the Eskom power stations from 2008/09 to 2013/14. The results show that: the current electricity generation mix is not efficient due to high cost and risk; and following the 2007 and 2008 load shedding events the entire portfolio capacity was increased marginally and the OCGT stations fuel costs increased substantially. Future work would be to apply this study to the period following the 2014 and 2015 load shedding events.