Professors David Pimentel and Bruce Dale debated the use of net energy analysis for determining "The Cost of Biofuels. Answer the following questions based on this article. Table 12.4 contains data that the authors use for their arguments. 

1. Calculate the energy ROI for gasoline and ethanol today. Make reasonable assumptions. 

2. Dr. Dale argues: "Net energy analysis is misleading because ethanol's net energy was never compared with gasoline's net energy. The comparison is easily done. [From the table above,] ethanol's net energy is 1.0 minus the sum of (0.04 + 0.28+ 0.41) times 100, which equals +27%, while gasoline's net energy is 1.0 minus the sum of (1.1 + 0.03 + 0.05) times 100, which equals -18%. Gasoline's net energy is therefore significantly lower than ethanol's." Check the validity of this calculation. You may need to use your calculation in (1). Why does gasoline look so much worse than ethanol in this calculation?

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Table 12.4 Data for net energy analysis of some transportation fuels. Energy input (in MJ) to generate 1 MJ from fuel Petroleum Natural gas Coal Other TOTAL Gasoline Corn ethanol Cellulosic ethanol 1.10 0.04 0.08 0.03 0.28 0.02 0.05 0.41 -0.02 0.01 0.04 0.02 1.19 0.77 0.10 Greenhouse gases 94 77 11