Sustaining the performance of diverse energy management systems through reactive maintenance

Energy management systems (EMSs) form an important part of many Demand-Side Management (DSM) projects implemented on South African mines. Sustained EMS performance is only possible with proper system maintenance. However, it is challenging to maintain a large number of EMSs remotely. One of the main challenges associated with sustained EMS performance is changing production strategies. Although these changes require prompt revision of the EMS control strategy, energy services companies (ESCOs) typically use the daily EMS performance to assess the need for corrective maintenance. Thus, to improve the efficiency of EMS maintenance, a supervisory system was developed to facilitate reactive maintenance of different EMS technologies. This system prompts EMS maintenance based on diagnostics of key EMS components, the specific control strategy, and overall EMS performance. Results from two case studies using the system showed an increase in the EMS operational availability from 87% to 97%. The average EMS performance also increased from 1.7 MW to 2.6 MW. Seven additional implementations also improved average EMS operational availability from 72% to 95%, resulting in a combined performance of 19.2 MW compared to the 15.5 MW target. The abovementioned results prove that the developed supervisory system is able to facilitate sustained performance of a growing number of EMSs, by increasing the efficiency of the maintenance process.