From: John Burgeson (firstname.lastname@example.org)
Date: Mon Jan 20 2003 - 17:48:25 EST
Glenn: I really appreciate the analysis. As you may know -- I'm teaching a
class right now on science/religion/ethics and this problem fits right in
with some material I have on how science can inform our decisions and also
how it can be misused. Of course its not the science that is misused as much
as the scientists who selectively report the data that supports their case.
I started the course 3 weeks ago with quotations from one of my favorite
Greek philosophers, Epicurus, who laid out the three rules of "good science"
1. Clear definitions
2. Consider ALL the data
3. Ascribe nothing to the gods (methodological naturalism)
It appears that the source I cited broke rule 2.
John W. Burgeson (Burgy)
>From: "Glenn Morton" <email@example.com>
>To: "John Burgeson" <firstname.lastname@example.org>,<email@example.com>
>Subject: RE: Date: Mon, 20 Jan 2003 21:30:36 -0000
>You wrote on Sunday, January 19, 2003 11:24 PM
> >Glenn: I found the following at the www.whybiotech.com website:
> >Higher Corn Yields are Making Ethanol More Energy Efficient
> >New USDA study says ethanol now yields 34 percent more energy than
> >it takes
> >to produce it.
> >A recent U.S. Department of Agriculture study found that ethanol
> >is becoming more energy-efficient all the time because corn yields are
> >rising, less energy is required to grow it, and ethanol conversion
> >technologies are becoming more efficient.
> >Is this consistent with the views of the oil industry? What might be the
> >limitations of replacing gas derived from oil with gas derived from corn?
>First, let me state that the opinions I express are mine not the oil
>industry's. I don't know if it has an opinion, but if it does, it hasn't
>given it to me. :-)
>Seconly, I got the original US Ag dept article this morning and read it on
>the plane to London today. The article has some interesting comments.
>First, they are correct that improving efficiencies are closing the gap
>between energy positive and energy negative positions. However, there are
>couple of things they omit or ignore which tell me that they haven't yet
>shown that the manufacture of ethanol is energy positive yet.
>Their table 6 summarizes the situation:
>Process BTU/gallon ethanol
>Corn production 21,598
>Corn transport 2,263
>Ethanol Conversion 51,779
>Ethanol distribution 1,588
>Total energy used 77,228
>Given an 83,9600 btu/gallon energy content of Ethanol they come up with a
>net energy value of
>+6,732 BTU per gallon.
>It is interesting what they leave out of the calculations. They state:
>"Another major difference between the Pimentel studies and most other
>studies is that his estimates include energy expended on capital equipment.
>Pimentel's estimate for converting ethanol is about 7,000 Btu/gal higher
>because it includes energy for steel, cement, and other materials used to
>construct the ethanol plant, components not included in most other
>Hosein Shapouri and James A. Dulfield and Michael Wang," The Energy Balance
>of Corn Ethanol: An Update", USDA AER-814, (2002), p. 3
>And then they don't include this in their estimate of the economics of
>ethanol either. Thus, they are implicitly assuming that one doesn't have
>spend energy on the plant itself in this equation! Leave it to government
>bureaucrats to ignore capital investment! Correcting for this, one
>immediately takes their 'uncredited calculation' into the red.
>Secondly, they then credit the calculation by taking the waste products and
>treating them as energy positives. They are energy positives, but they are
>not fuel oil. The coproducts are distiller's dried grains, corn oil, corn
>gluten meal and corn gluten feed. I find this a bit misleading to the
>because it is taking advantage of the conservation of energy to act as if
>are getting useful fuel from an energetically advantageous process. If we
>accounted for all the energy in all the systems, we would have all the
>energy after the processing of ethanol.
>One other worry I have about this paper is that they claim 80% efficiency
>for gasoline and diesel in transportation. That seems about 4x too high
>from what I know of transporation efficiencies.
>I also noted a pattern in all the studies they cited. All but one of the
>private papers said the process was negative. All studies published by the
>government or lobbying groups say it is positive. Not exactly a comforting
>pattern given that this is a government report.
>for lots of creation/evolution information
>personal stories of strugg
Protect your PC - get McAfee.com VirusScan Online
This archive was generated by hypermail 2.1.4 : Mon Jan 20 2003 - 17:52:12 EST