Technical analysis of crop residue biomass energy in an agricultural region of Ghana

• Potential of crop residue and corresponding ethanol was estimated.
• Ethanol demand was compared to gasoline and cooking fuel demand.
• Net energy balance was 1719 MJ with output to input ratio of 1.31.
• Sustainability assessment important to address environmental and socio-economic concerns.

The aim of this study was to assess crop residue biomass potential for second generation biofuel production in the Lawra–Nandom district of Ghana. The methods used in this study included interviews, survey, field and laboratory experiments. The findings show that total annual crop residues production in the Lawra–Nandom district amounts to about 272,000 t. Among the major crops grown in the district, sorghum crop generates the largest quantity of residues, contributing 59% by weight of the total residues. Ethanol production potential could reach 40 million litres if 40% of the average residue generated between 2003 and 2012 were used for energy purposes. The net energy balance of the biofuel production process was 1718.7 MJ with a ratio of energy output to input being 1.31. Second generations biofuels are expensive compared to first generation and research efforts aimed at technology improvement and cost reduction must intensify in order to make the technology attractive to developing countries.