Green electricity generation potential from biogas produced by anaerobic digestion of farm animal waste and agriculture residues in Iran

Biogas is a practical way of recycling bio-wastes that can be utilized as a fuel for co-generation of electricity and heat. Livestock and agriculture-based resources have considerable potential for bio-power generation mainly due to their comparatively low cost. However, the contribution of agricultural residues has been neglected within this context in Iran. This study aims to assess Iran's potentials in bio-power generation from both animal and agriculture-based resources to provide an accurate/realistic estimate of the resource availability. The studied energy crops were wheat, rice, barley, maize, potato, apple, grape, alfalfa and other industrial crops including sugar cane and sugar beet. The total amount of agricultural waste is assessed to be 24.3 million tones that can be considered potential feedstock to produce 6,542 million m(3) of biogas, 2,443 million liters of bio-butanol, and 2,082 million m(3) of bio-hydrogen. In addition, the biogas potential from livestock and slaughter wastes is estimated to be 11,523.84 and 16,026 million m(3)/year, respectively. The findings indicated that there is considerable potential for bio-power generation in Iran. The analysis estimated that Iran's total potential for bio-power generation from these organic matters was around 62,808 x 10(6) kWhyear(-1), accounting for 27% of the total electricity consumption in the country. The greenhouse gas emission mitigation from bio-based electricity generation would be about 4,096 thousand tons of CO2-eq/year, which account for up to 0.6% of Iran's annual greenhouse gas emissions. To the best of the author's knowledge, this is the first report assessing the emission inventory and emission allocation of CO2 from both livestock manure and the open burning of crop residues in Iran. This paper provides valuable insights and information for policy-makers to formulate long-term energy policy by taking advantage of these bio-wastes in Iran as a case study. (C) 2020 Elsevier Ltd. All rights reserved.