The strategies employed in the management of continuity of supply to the Southern African aluminium reduction smelters during power system emergencies

Aluminum reduction smelters will solidify when the power is off. This case represents both a financial and technical shutdown of operations. The consequences to both owner and supplier of electrical energy are devastating. The power supply system connecting smelters to power stations are planned and designed to an N-1 level of contingency; allowing any one item of circuit to be removed from service whilst maintaining full continuity of supply to the smelter. The paper discusses real events that challenged continuity of supply. These events delivered the best from both supply and customer engineers