This question is based on the debate between Professors Dale and Pimentel about "The cost of biofuels". One statement made by Professor Dale is as follows. 

One megajoule of coal is simply not equivalent to 1 MJ of petroleum. If you doubt this, try grinding up some coal, put it in your gas tank, and see how far you can drive on coal's energy content. Pimentel's "net energy" analysis is akin to adding 10 U.S. dollars, 10 Mexican pesos, and 10 Indian rupees to get $30- an absurdity. Different energy carriers and different currencies have different qualities. They cannot simply be added together as Dr. Pimentel does.

1. What is the common way of dealing with the aggregation of different currencies? Suggest a way to address the difference in resource quality. 

2. Use emergy analysis to calculate metrics based on the data in Table 12.4. 

Table 12.4:

Which fuel looks better from this calculation?

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