The potential of sustainable biogas production from biomass waste for power generation in Pakistan

Pakistan is facing a severe electricity shortfall due to rapidly growing demand leading to 8–12 h d−1 power outages in rural areas in summer. Predominant use of imported fossil fuels for electricity generation is exerting a huge burden on the economy and causing immense damage to the environment in the form of GHG emissions. One of the best energy sources in terms of economy and emissions is biomass waste which is abundantly available in Pakistan in the forms of animal manure, poultry waste, sugarcane bagasse and kitchen waste. This paper critically analyses the potential of these largely underutilized biomass waste resources for biogas production as a Waste-to-Energy technology to overcome Pakistan's power crisis. Potential biogas production from each resource and its subsequent utilization in power generation is calculated for Bahawalpur (a division of Pakistan) as a case study and for the whole country Pakistan as well. Remarkable results come out to be 11.65 M m3 d−1 of biogas production potential which can generate 3059.7 GWh y−1 electricity for Bahawalpur division alone. The results for the whole Pakistan are 226.8 M m3 d−1 of biogas production potential and corresponding electricity generation of 59,536 GWh y−1 which accounts to be 49.4% of the total power generation for the year 2018. The most striking finding is that power generation from biogas will be enough to eliminate Pakistan’s power shortfall. There is a possible market of 12.9 B USD y-1 corresponding to total bio-fertilizer generation of 340,800 kt y-1 from anaerobic digestion (AD). Findings of this paper present the government of Pakistan a critical consideration of widespread use of biogas technology in future and draft a proper Waste-to-Energy policy accordingly. The conclusion is that the biogas production and its subsequent use in electricity generation from biomass waste is the sustainable and eco-friendly renewable energy source which could resolve power crises and environmental and waste management issues in Pakistan. Biogas as a source of energy can be an important component for sustainability transition in Pakistan. This study could be a good reference for other developing countries too.