Biogas production potential and utilization from agricultural and livestock waste in Bangladesh

Abstract

Bangladesh is one of the world’s most densely populated and agriculture-dependent nations, generating enormous quantities of organic waste from crop residues, fruit and vegetable waste, and livestock manure across its rural areas. Yet, these raw materials have remained uncharacterized in terms of their spatial distribution and availability of these materials in the context of biogas production in the rural areas of Bangladesh, while millions of people still lack access to clean energy sources in the country. The main purpose of this thesis is to undertake a comprehensive secondary data analysis of the types of raw materials available in the country for agriculture and livestock farming in terms of their quantities and potential for producing biogas. The research will be based on the latest information provided by the BBS Yearbook of Agricultural Statistics 2023 and the Department of Livestock Services Annual Report 2022-23. The primary focus of this research will be characterizing the raw materials in terms of their availability and quality, with biogas energy yield being a secondary focus.

The results indicate that the net available crop residue generated in the rural areas of Bangladesh amounts to 57.4 Mt annually, with the majority being rice straw at 49.7 Mt. Fruit/Veg. waste amounts to 1.24 Mt annually. Livestock/poultry generates 326.85 Mt of manure annually, with cattle manure being the primary feedstock at 295.65 Mt. The total theoretical biogas potential of these raw materials amounts to 15.26 billion m³ annually from livestock/poultry sources and an additional 31.8 TWh/year of energy equivalent from crop residues. The results of the multi-criteria suitability analysis indicate that cattle manure and rice straw are the most accessible sources of biogas in the rural areas of Bangladesh, with maize Stover and poultry litter being the emerging sources of biogas. The existing biogas programme currently utilizes only 2.67 TWh/year of the total available potential of 59.1 TWh/year, which is over 95%.

The study concludes that Bangladesh holds a vast and growing rural bioenergy feedstock base. Unlocking this potential requires targeted raw material collection strategies, co-digestion programmes, and rural infrastructure investment. Biogas end-use and emission impacts are noted as secondary outcomes that would naturally follow from effective raw material utilization.