Design of a Small-Scale Bioenergy-to-Electricity Generation System for Rural Communities in Bangladesh

Abstract

Motivated by the urgent need to address Bangladesh’s rural electricity crisis, where over 30 million people lack stable grid access, and the environmental and health impacts of fossil fuel-based power, this study designs a 50 kW small-scale bioenergy-to-electricity generation system for rural communities. Utilizing anaerobic digestion, the system processes 15 tons of household biowaste daily, including cow dung and kitchen/agricultural waste, from 375 households (1,500 cows, 4 cows per household) to produce 600 m³ of biogas, yielding 1,200 kWh of electricity per day. Operating at 30–35% generator efficiency, the system converts biogas at 2 kWh/m³, meeting the electricity demand of approximately 375 households. The design includes biomass collection (2–3 hours/day), preprocessing (1–2 hours/day), continuous 24-hour digestion, gas cleaning (25 m³/hour), and electricity generation. Replacing fossil fuel-based power, it reduces CO₂ emissions by 1,080 kg/day, achieving annual savings of 393 tons. A community-engaged framework ensures affordability, scalability, and sustainability through local participation, cost-sharing, and capacity building. This research provides a replicable model for decentralized electrification, aligning with Bangladesh’s renewable energy targets and global sustainability goals.