Performance Assessment and Optimization of a Micro-Hydropower Plant: Case of Kigwena in Burundi

Abstract

A significant characteristic of the power sector in Burundi is a very low electrification rate (about 10 %), mainly dependent on hydro-power and with frequent power outages in dry seasons. Despite having potential for developing various renewable energy technologies, the Burundian Agency for Rural Electrification promoted usage of micro-hydropower plants. Hence, most of these plants are affected by stream-flow fluctuations, especially during the dry seasons. This study aimed to identify a simple, reliable, viable and cost-effective hybrid power system to compensate the power supply intermittencies of the Kigwena micro-hydropower plant. The optimization of the best hybrid combination was evaluated using the microgrid software, HOMER Energy. The study concluded that the most suitable complementary energy resource was solar-PV and the utility grid for smoothing unexpected intermittencies. Economically, these renewable energies were found to be the most techno-economical viable option to upgrade the capacity of the hydropower with the lowest Levelized Cost of Energy of US$ 0.0334 /kWh. This cost was within the range in comparison to the current electricity tariff in Burundi ranging from US$ 0.023/ kWh to US$ 0.072/kWh. The study would be a replicable model for other areas facing similar challenges.

Keywords: Renewable Energy, Micro-Hydropower, Optimization, Hybrid Power System