Life cycle environmental and economic impact assessment of alternative transport fuels and power-train technologies

Assessment of the sustainability of alternative transport fuels is essential for directing the development while reducing their impacts. The aim of this paper is to assess the environmental and economic life cycle impacts of alternative transport fuels and compare with conventional fuels. The sustainability assessment was performed for selected fuels, including diesel, gasoline, liquefied petroleum gas, biodiesel, ethanol, hydrogen, fuel cell and electricity, using SimaPro 8.05 life cycle assessment software and Recipe methodology. The study revealed the highest environmental impacts for ethanol flexi fuel technology, followed by biodiesel at close to 80% to the ethanol impacts, liquefied petroleum gas at 45%, gasoline at 30%, diesel at 25%, electricity at 15%, compressed natural gas at 5%, and the minimum for hydrogen technology with only 3% of environmental impacts comparing to ethanol. The total economic costs (including capital costs and operating costs) on per km basis are the highest for battery electric vehicles (electricity fuel) followed by ethanol based flexi fuel vehicles, biodiesel, diesel, gasoline, compressed natural gas, hydrogen (fuel cell) and the minimum for liquefied petroleum gas. The combined environmental and economic impacts revealed hydrogen fuel cell is the best performing fuel technology with only 3% of the impacts of ethanol.