Voith is to modernize three generators at the Drakensberg pumped storage plant in South Africa in a contract valued at around Eur 11 million.

The order from operator Eskom covers manufacture, installation and commissioning of the three machines, which will take place step by step and during normal operation to mid 2018. In a statement, Voith said that during the bid phase it convinced the operator with a technical concept improving the performance of the machines by dedicated measures.

“These measures ensure a reduction of operating temperature and machine vibrations so that their lifetime can be extended significantly. After the modernization the generators will show at least 40 further years of operation”, said Martin Althoff, generator expert and technical offer manager of the Drakensberg project at Voith Hydro Germany.

Drakensberg pumped storage power plant has a total installed capacity of 1000MW and is the second largest of its kind in South Africa. The most unique feature of Drakensberg is that the power plant is built completely underground. Only shafts and transmission lines can be seen on the surface whereas the four reversible pump turbines are placed approximately 52 floors below ground.

The power plant has been in operation since 1981 and considerably contributes to energy grid stabilization.