compared. Quantities are expressed in standard units that are commonly used in the United States. Greenhouse gas emissions, however, are expressed in tonnes of CO2 equivalent (CO2 eq), the common metric used by the Intergovernmental Panel on Climate Change.

The Panel on Alternative Liquid Transportation Fuels provides estimates of total costs of fuel products that include the feedstock, technical, engineering, construction, and production costs that were put on a consistent basis and at one time. However, the price of fuel products is dynamic because the costs of feedstock, labor, and construction fluctuate and are influenced by multiple factors, including shortages in labor or construction material, government policies, and the economic environment; and the cost estimates are sensitive to debt-to-equity ratios, interest rates, the discount rate, and specific corporate goals (such as return on capital and risks). Therefore, the cost estimates in this report are not predictions of fuel costs in 2020; rather, they provide a comparison of technologies on a level playing field. Cost estimates in this report do not include taxes or subsidies. Gasoline and other potential taxes and carbon prices could change the relative competitiveness of alternative fuel choices.


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