Unbalanced Loading; An Overlooked Contributor to Power Losses in HESCO

Abstract

Energy losses are hampering progress of the developing countries like Pakistan by putting extra financial burden that could have been used for development projects of the power sector. Electricity consumers are paying high energy cost despite of facing long duration load shedding and frequent small duration supply interruptions. Although electricity theft is considered as major cause of the losses but technical losses caused by aged distribution network and poor operation planning is also on higher side. Unbalanced loading caused by single phase loads supplied by three phase four wire system is an ignored source of power loss in distribution utilities of Pakistan, which is controllable by small investment on monitoring and line staff dedicated for load balancing. In this paper, one of the distribution feeder in Hyderabad is selected for analysis of power losses caused by unbalanced loading. Exact data collection, modelling and simulation of the selected feeder shows high load unbalance. Balancing of the observed unbalanced loads result in power loss reduction of 62.8 kW amounting to an annual savings of Rs. 2.68 Million. It is recommended to HESCO and other distribution utilities in Pakistan to depute dedicated line staff for monitoring and balancing of the transformer loads to increase energy efficiency. Smart meter installation at all transformers will provide unbalance data for pre-set time intervals for balance analysis.