The value of maintaining a DSM load shifting project on mine dewatering pumps

A large number of load shifting projects have been successfully implemented on mine dewatering pumps since the inception of Eskom´s Demand Side Management (DSM) initiative in 2003. In addition to electrical cost savings, mines have benefitted from reduced operational costs and the installation of new equipment such as electrically actuated valves, pressure sensors, programmable logic controllers, etc. This equipment enables the automatic stopping and starting of dewatering pumps by a real time energy management system (REMS) that aims to minimise the amount of pumps utilised in peak periods. Experience has shown that some mines do not always have the capacity to ensure that DSM projects are sufficiently maintained. This leads to gradual deterioration of performance. In this paper, a case study on the re-implementation and maintenance of a load shifting project on the dewatering pumps of a typical South African gold mine is presented. We discuss solutions to the challenges associated with this process and provide results that prove the value of re-implementing and correctly maintaining a load shifting project on mine dewatering pumps.