Environmental benefits on a life cycle basis of using bagasse-derived ethanol as a gasoline oxygenate in India

Bagasse is the fibrous residue generated during sugar production and can be a desirable feedstock for fuel ethanol production. Excess bagasse left after satisfying the mills’ energy requirements can be used in a bioconvesion process to make ethanol. A life cycle assessment (LCA) was conducted to quantify the environmental benefits of diverting excess bagasse to ethanol production as opposed to disposing it through the current practice of open-field burning. The LCA results demonstrated lower net values for the ethanol scenario for the following: carbon monoxide, hydrocarbons (except methane), SOx, NOx, particulates, carbon dioxide, methane, and fossil energy consumption. Reduced carbon dioxide and methane emissions for the ethanol scenario also lower its greenhouse potential. Additional drivers are the lower values observed for the following impact assessment categories for the ethanol scenario: depletion of natural resources, air acidification potential, eutrophication potential, human toxicity potential, and air odor potential. Specifically, deployment of the bioethanol option, due to its significantly lower greenhouse potential, can be facilitated via the Clean Development Mechanism, as specified under the Kyoto Protocol.