Water use targets in terms of litres of water used per unit of electricity sent out are set for each power station every year. The water targets are linked to the operational sustainability index contained in performance compacts, which are in turn linked to business unit and individual performance bonuses. The targets are benchmarked against historical as well as theoretical water consumption for each particular type of plant.

Since the 1970s, Eskom engineers have been trying to find ways to conserve South Africa ’s limited water resources. The most effective solution so far is dry cooling. South Africa has the two biggest dry-cooled power stations in the world. The technology has resulted in a saving of over 180 million litres of water per day that would normally be lost through evaporation.

Matimba power station near Lephalale in Limpopo is the world’s largest direct-dry-cooled station. It uses closed-circuit cooling technology to produce more than 4 000MW. Kendal power station near Witbank is the largest indirect dry-cooled power station in the world. This process entails the cooling of water through indirect contact with air in a cooling tower. At Eskom’s wet-cooled stations, improved water management allows extensive re-use of water. In line with the so-called zero liquid effluent discharge policy, water is cascaded from good to poor quality uses until all pollutants are finally captured in the stations’ ash dams.