Impact of embedded generation on losses in Kanungu power distribution network.

Abstract

The worldwide increasing demand for electricity, coupled with government policy changes for “green” energy stipulated in Uganda’s Energy Policy 2002 and the Uganda Renewable Energy Policy 2007 has led to significant interest in Distributed Generation (DG) /Embedded Generation (EG). Integrating EG into an electricity network, especially close to load centers, has many significant benefits/impacts on the protection, stability, losses and voltage of the distribution networks. In this study, an analysis of the impact of EG on distribution network losses was undertaken. The analysis was carried out for two extreme loading conditions of the network, that is, the peak load and light load conditions. The case study was modeled using the Power system simulator for engineering (PSSE) software as well as the extended Newton- Raphson method which was used for analysis. The results show that introducing EG in a distribution network reduces the technical losses at 75% loading; beyond which voltage violations will be experienced. For Kanungu power distribution network, loading the EG at 75% (4.8MW) resulted into losses of 4.2% with no voltage violation, loading the EG below 75% resulted into increased losses of up to 54.5%, and loading the EG above 75% resulted into voltage violation. Therefore, introduction of embedded generation in a distribution network requires the reconfiguration of the network to optimize the embedded generator up to the level of the lowest losses and acceptable voltages. Furthermore, a cost benefit analysis was undertaken to examine whether to operate the embedded generator of 6.4MW at a capacity of 4.8MW (ideal operations to minimize losses and maintain acceptable voltage) and therefore pay for deemed energy (undispersed energy) or to continue running the embedded generator at full capacity of 6.4MW and suffer losses of up to 54.5% in the case study distribution network.