WATER AND GREENHOUSE GAS TRADEOFFS ASSOCIATED WITH A TRANSITION TO A LOW CARBON TRANSPORTATION SYSTEM

Transportation fuels are heavily dominated by the use of petroleum, but concerns over oil depletion (e.g., peak oil), energy security, and greenhouse gas emissions from petroleum combustion are driving the search for alternatives. As we look to shift away from petroleum-based transportation fuels, most options consume and withdraw more water during their life cycle. Thus, shifting to alternative fuel and energy supplies for transportation will likely increase water use for the transportation sector. Previous work suggests that water consumption for transportation could reach 10 % of total U.S. water consumption when meeting the Federal Renewable Fuels Standard mandate at modest irrigation levels for feedstock crops (corn, cellulosic grasses) in combination with other alternative fuels and vehicle technologies (electri