Biogas Potential of Indian Organic Wastes: Technologies, Challenges, and Future Prospects

Abstract

India generates enormous quantities of organic waste from agricultural activities, livestock farming, food-processing industries, municipal solid waste, and domestic kitchens. Improper disposal of these biodegradable materials contributes to greenhouse-gas emissions, groundwater contamination, odour nuisance, and land pollution, while the country simultaneously faces rising energy demand driven by urbanisation, industrial growth, and population expansion. Biogas technology offers a sustainable route to reconcile these pressures by converting biodegradable waste into renewable energy through anaerobic digestion. This review consolidates the biogas potential of the major Indian organic feedstocks — cattle dung, crop residues, kitchen waste, sewage sludge, and agro-industrial residues — and relates their physicochemical characteristics to methane yield. The four stages of anaerobic digestion (hydrolysis, acidogenesis, acetogenesis, and methanogenesis) are described, and the influence of key operational parameters (temperature, pH, carbon-to-nitrogen ratio, hydraulic retention time, and organic loading rate) on process performance is evaluated. Recent advances in pretreatment and co-digestion that enhance biodegradability and gas yield are summarised, and the principal barriers to large-scale deployment — feedstock logistics, waste segregation, capital cost, and technical capacity — are critically examined. The review concludes that India holds substantial potential for decentralised biogas generation, particularly in rural and peri-urban regions, and that the integration of improved digestion technologies, source segregation, and supportive policy can advance sustainable waste management, renewable-energy supply, and a circular economy.