TITLE:
Optimal Analysis and Performance of Rwandan Electrical Network with High Penetration of Interconnected PV Rooftop Microgrids
AUTHORS:
Emmanuel Nisingizwe, Mahamat Adoum Abdoulaye, Cyrus W. Wekesa, Michael J. Saulo
KEYWORDS:
Rooftop PV Microgrids, Battery Storage, Electrical Distribution Networks, Evaluation Criteria, Energy Management
JOURNAL NAME:
Journal of Power and Energy Engineering,
Vol.13 No.9,
September
26,
2025
ABSTRACT: This study investigates the optimal integration and performance of interconnected rooftop photovoltaic (PV) microgrids within Rwanda’s electrical distribution network, supporting the nation’s goals for widespread electrification and renewable energy adoption. Through a detailed case study, the research addresses technical, economic, operational, social, and environmental challenges associated with high PV microgrid penetration. Advanced simulations conducted using MATLAB evaluate the system’s performance across various scenarios, focusing on voltage stability, power quality, and energy losses. The findings reveal that interconnected microgrids significantly enhance network resilience, energy access, and renewable energy integration, particularly in remote areas. Key technical results demonstrate a robust and efficient system, with a System Self-Sufficiency Index (SSSI) of 0.4186, a System Self-Consumption Index (SSCI) of 0.3088, an excess energy generation of 3568803.59 kWh, zero unmet load, a very low Loss of Power Supply Probability (LPSP) of 0.0096, and a total energy transfer of 3913515.11 kWh. Economic analysis highlights strong financial viability, with a low Levelized Cost of Energy (LCOE) of $0.04/kWh, a Net Present Cost (NPC) of $8867793.27, and a payback period of 9.6 years. Socially, the optimized systems are expected to create three direct jobs per installation, improve the Human Development Index (HDI), and achieve high social acceptance, supported by a 95% positive response rate toward renewable energy adoption. Environmentally, the systems avoid 10374932.8 kilograms of CO2 emissions and achieve a remarkable renewable energy penetration rate of 97.75%. Overall, this study demonstrates the technical, economic, social, and environmental benefits of high PV microgrid penetration in Rwanda and provides actionable insights for policymakers, engineers, and stakeholders aiming to maximize the advantages of microgrid integration while addressing associated challenges.