A Design Approach of Off-grid Hybrid Electric Microgrids in Isolated Villages: A Case Study in Uganda

Abstract Rural electrification in isolated areas of developing countries can be considered a pivotal factor for economic and social growth, moreover the absence of electricity grid in villages leads to an elevated usage of diesel generators that entails large costs and high CO 2 emissions. This paper presents a design methodology and economical evaluation to implement a hybrid power system composed of a photovoltaic power plant, electrical storage and a backup system of diesel generators in an isolated village in Uganda named Ntoroko. Results show that the usage of battery storage is economically crucial, particularly in areas with a low daily electrical consumption and peak loads increasing in the early morning and late evening when the solar radiation is lower and PV array has a reduced power production. Results disclose that the optimal configuration of the hybrid system (PV-storage-diesel generators), despite its high investment cost, presents an economic benefit of 25.5 and 22.2% compared to the usage of only PV array and diesel generators and only diesel generators and a reduction of fuel consumption equal to 74.7 and 77%, respectively.