Abstract
Road vehicles account for a significant share of air emissions in today's major urban centers. There are efforts by Philippine government to increase the usage of alternative fuels as substitutes for diesel oil. The most promising fuels include compressed natural gas (CNG) and biodiesel derived from coconut oil. The potential environmental benefits of these alternative fuels can be measured using life cycle assessment (LCA) methodology. This paper presents the application of fuzzy multiple attribute decision making (FMADM) in an LCA model for comparing alternative transportation fuels. The methodology allows quantitative information on the transportation systems' material and energy flows to be integrated with qualitative information reflecting such aspects as the social acceptability of different types of environmental damage. Fuzzy numbers are used to represent uncertainties in the data so that the model can predict both the magnitude of the environmental impacts of the alternative fuels and the corresponding confidence levels of these estimates. Results of a case study show biodiesel to be superior to both CNG and diesel in terms of overall environmental impact.
