Performance Evaluation of Off-Grid Power Supply for Rural Electrification in Kenya: The Case of Habaswein Hybrid Minigrid

Abstract

To save money spent on diesel and reduce environmental impacts, the Kenyan government started a program of integrating wind and solar in off-grid power generation stations. This initiative commenced in the year 2010, however, detailed performance and sustainability studies of the hybrid stations have not been conducted. This research sought to evaluate and address this problem using Habaswein hybrid power generation station as a case study. The power station comprised of three diesel generation units of 410 kW, 360 kW and 280 kW capacity, 30 kW solar PV and 60 kW wind power systems. The study methodology was inductive research to build a theory, using quantitative data from Kenya Power and Lighting Company (KPLC) and Ministry of Energy, and qualitative data from interviews with KPLC staff and customers. Photovoltaic Geographical information System (PVGIS), Excel and Hybrid Optimization of Multiple Energy Resources (HOMER) PRO software were used for the analysis. The electricity access is currently not 100% in Habaswein Division, but electricity is equitably distributed to all categories of consumers across multiple villages. Further, reliability of power supply is fair, with relatively high frequency of power outages which lasts for short durations as a result of switching between diesel generators. Secondly, the study found that solar and wind energy potential in Habaswein was high. WindyCator showed wind speeds averaging 6.04 m/s, at a 20 m height, while irradiation was 6.28 kWh/m2/day. Lastly, in order to ensure maximum utilization of renewable energy resources and enhanced performance, the optimal hybrid design mix consists of: 100 kW diesel generator to meet the base load, 410 kW diesel generator to meet the peak load (switch over from 100 kW), and 578 kW solar PV. It is recommended that the 360 kW and 280 kW diesel generators be decommissioned and replaced with a new 100 kW generator and an additional 548 kW solar PV. In addition, proper training and capacity building of KPLC’s personnel in operation and maintenance (O&M) is required.