Until Professor Pimentel's draft has been published,
it is inappropriate for us to post it on the Web. However, in this
draft, he is quite critical of the 1995 USDA report by Shapouri et al.
1995 which the ethanol industry is fond of citing as evidence that ethanol
yields more energy than it requires to produce. Professor Pimentel notes
"...energy inputs for machinery, irrigation, and for transportation, which
have significant costs, were omitted. Another way of reducing the calculated
energy inputs for ethanol production is to arbitrarily select lower production
costs for some of the inputs. For instance, Shapouri et al. (1995) list
the cost of a kilogram of nitrogen production as 12,000 kcal/kg, considerably
lower than FAO (1999) which list the cost of nitrogen production at 18,590
kcal per kg. Obviously, using the lower figure reduces the energy inputs
in corn production for nitrogen fertilizer by about 50%."
An issue Professor Pimentel's draft did not address is
what motivates the USDA to produce biased research like this in the first
place. Read on....