Design of Solar PV-Biogas Hybrid Power System for Rural Electrification in Ghana

Abstract

Globally, reliable access to electricity improves the well-being of people, provides quality education, and ensures good health. In this study, a solar PV-biogas hybrid power system for electrification is designed for Mankramso community located in the Offinso-North district in Ghana. The technical potential of crop residues and livestock manure available in the community for anaerobic digestion is assessed. Thereafter, the Hybrid Optimization Model for Electric Renewable (HOMER) software was used to perform technical, economic and greenhouse gas emission analysis. The daily electric load demand in Mankramso community was estimated at 262.05 kWh/d, for 400 households, school, health clinic, commercial loads (flour mills, cold store, and small businesses), church buildings and streetlights. The findings show that the system configuration which comprises of 18.6 kW of PV panels, 45 kW of biogas generator, 62 kWh of battery storage and 15.7 kW of converter is the most optimal hybrid power system configuration compared to other power system configurations to meet the daily electric load. The solar PV-biogas hybrid power system will generate annual electricity of 105,479 kWh/yr and the community AC loads will consume 95,633 kWh/yr of electricity. This optimal hybrid power system has levilized cost of energy (LCOE) of US$ 0.188/kWh and a total net present cost (NPC) of US$ 219,442. The LCOE is only 10.6% higher than current LCOE (US$ 0.17/kWh) for residential tariffs in Ghana. Moreover, sensitivity analysis on the effect of changes in nominal discount rate, components (PV panel, biogas generator and battery) prices and price of biomass feedstock on the optimal hybrid system LCOE and NPC is also presented. It is recommended that rural electrification projects of such nature are combined with innovative energy efficiency practices to help rural communities have access to reliable and affordable electricity.