Joel posted a URL for a recent study:
> Estimating the Net Energy Balance of Corn Ethanol
The take home message for me is that it is critical to get everybody to
agree on what assumptions to use, or at least to acknowledge the ones
they make. One very important issue is whether or not to include the
embodied energy of the equipment used to plant, harvest and otherwise
process the corn. To me it seems "obvious" that this is necessary
information, but I keep finding that assumptions of obviousness are
nearly always wrong. It is not obvious to these authors.
I'd be quite interested to see how everybody here lines up on the two
sides of this issue.
The study is quite interesting overall and contains quite a bit of good
information.
But how strange to have an energy balance study done by economists. This
does not reassure me about the likelihood that the conservation laws
which form the basis for the physical sciences will inform this study.
The authors have shown that the outcome, and specifically whether the
energy balance ratio is greater than or less than unity (the entire
point), is highly sensitive to several initial assumptions.
A quote from the study follows:
"Most studies, including this one, include only primary energy inputs in
their NEV estimates. Secondary inputs, such as energy required to build
ethanol facilities and produce transportation equipment are extremely
difficult to quantify. For example, collecting data on the energy
embodied in an ethanol plant would require a tremendous amount of data
on a wide range of building materials. It would be necessary to allocate
this energy among all the products manufactured in the plant over its
lifetime. After going through all this trouble, the final result would
add very little to the total energy value of a gallon of ethanol."
I think it is remarkable how they know it is insignificant when they do
not know how to get the information. This is reminiscent of the
sweeping under the rug of "externalities" so warmly espoused by some
members of the same profession.
Loren Muldowney
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