Investigate the impact and benefits of integrating Kabulasoke solar power plant into the nearby distribution network

Abstract

Kabulasoke solar power plant (20MW) is located in Gomba district in Central Uganda, on the hills off UETCL substation and power produced is purchased by UETCL for further sale to end users.

However, power in the nearby distribution network is associated with high distribution losses due to long length of feeders, low power reliability and quality to the end users, high voltage drops, insecurity of supply among others. Therefore, there is a need to assess the impact and benefits of integrating this power plant to the nearby distribution network.

The purpose of this research is to investigate the impact and benefits of integrating Kabulasoke solar power plant into the nearby distribution network. To achieve the project objectives, the the neighboring distribution network was studied to identify the available options for interconnecting the above solar plant. The grid simulation model for the 33kV network between Mutundwe, Mityana, Kiriri, Masaka central and Masaka west substations was developed using Dig SILENT power factory 15.1 version.

Load flow analysis was performed on the network before interconnecting the solar plant. Loading for different feeders were compared with those obtained from Umeme limited, to ensure accuracy. The bus voltages for different busses were determined before and after interconnection of the solar plant at different points on the network. Grid losses and feeder loadings were also determined for the different interconnection options, and a cost benefit analysis made to access the different options.

Interconnection of the solar plant at Kiriri substation yielded stable bus voltages at the two substations. However, an interconnection on the Mityana-Kiriri feeder yielded more stable bus voltages due to better load distribution on the network. Running two distribution feeders to two substations yielded most stable bus voltages, although the option proved to be relatively expensive.

In conclusion, an integration of Kabulasoke solar power plant to the distribution network provided stable and reliable power, improved voltage profile and reduced distribution losses and feeder loadings