Verification procedures to ensure consistent energy metering

The majority of Energy Conservation Measures (ECM) implemented by South African Energy Service Companies (ESCOs), are funded by the Eskom Demand Side Management (DSM) initiative. In 2013 Eskom reported a total DSM savings of 595 MW. To measure this effect power usage data needs to be recorded. A slight variance with the accuracy of measurements will have a significant impact on the reported savings. It is therefore of critical importance to ensure consistent energy measurements throughout the life cycle of the ECM.A study was conducted in order to investigate how each step of the measurement process contributes towards the overall accuracy. Components investigated include instrumentation transformers, the Analogue Digital Conversion (ADC) process and the different signal processing techniques available. The study also investigated different power loggers and their impact on the overall accuracy. The study found that each component has the potential to affect the accuracy of the measurement. However, the most significant risk that affects the accuracy was not any specific component, but rather the process of installation and setup of the equipment. This prompted the development of a procedure to address the verification of measurements. The verification procedure consists of three main parts namely, Verify measurements of temporary power logger, Evaluation of data recorded and Verification of permanent power logger.