The project boundary,baseline emissions and project emissions of fuel ethanol projects were defined. The greenhouse gas （GHG） emission of 3 generations of bioethanol projects,including corn liquid fermentation,sweet sorghum solid fermentation and cellulose hydrolysis fermentation were analyzed. By introducing a secondary emission reduction accounting system for the resource utilization of by-products, the maximum carbon emission reduction potential of each generation of bioethanol processes was systematically revealed. The results show that the sweet sorghum solid-state fermentation has the highest carbon emission reduction potential, with the maximum theoretical 5.14 ton CO₂e GHG abatement per ton of ethanol production. Cellulosic ethanol has greater carbon negative potential under the background of technological progress.

biomass energy  /  bioethanol  /  solid state fermentation  /  GHG mitigation​  /  biocarbon capture and storage  /  carbon emission reduction potential