[Peace-discuss] some figures on ethanol production from corn

[E. Wayne Johnson]

The microbes that ferment the starch-derived sugar consume about 1/3 of 
the energy in the starch and
release 1/3 of the carbon chains as CO2.  The oil, protein, and fiber 
ends up in the DDGS along with the
microbes and the mineral fraction.

The most serious inefficiency is the that the end products (ethanol and 
DDGS) are all in aqueous solution, about 11% ethanol max,
and that has to be distilled 3 times to reach a concentration suitable 
for use as fuel.

It is also a rather difficult SWAG calculation to make since the plants 
use a lot of heat recycling and co-generation to recapture a varying 
amount of the energy used in milling, cooking, distilling, drying, etc.

I used the probably quite adverse spin-doctored figures of  Pimintel 
(2005) .

1 bushel of corn could provide the energy needs of one person for about 
40 days, so 10 bushels of corn would work
for a whole year, and that would equate to about 27 gallons of ethanol 
generated from that corn.  Mind you
that corn would not work as the sole food supply but could be part of 
some theoretical varied diet.

*
One of the common features of calculating the energy cost of biofuels is 
to calculate the energy cost of producing the grain and the other 
various costs of bringing land into production.  One thing that should 
be noted is that we had 116 million acres in corn production in 1917 as 
compared with about 90 million this year.  It is true that modern 
production techniques use lots of energy intensive mechanization and 
chemical fertilizers and chemical pesticides, all of which have energy 
expenditures and environmental footprints associated with them.

But, how much of those energy and environmental costs are attributable 
to Ethanol production, per se?  Actually not as much as we would tend to 
think, because we are really not bringing vast new acres online or even 
intensifying corn production all that much.  Since suppliers of inputs 
to farms are charging what the market will bear, and since corn demand 
for ethanol has sent prices skyrocketing, the suppliers have increased 
their prices such that a bag of seed corn that cost $8 when I was a boy 
is now estimated at $300/bag for the 2009 planting season.  Likewise 
fertilizer, chemical, and land rent prices are increasing dramatically 
beyond the bounds of common sense, and some farmers are becoming very  
reluctant to plant corn in some areas because of the high input costs.

Actually farmers seldom plant corn for a particular use.  They dont 
think, "I am planting this corn for ethanol".  They are planting corn 
because they are hoping the market price and weather will be favourable 
for a profit.  Since corn is a commodity with good value, farmers have 
produced more or less the same number of acres of corn every year since 
the 70's with only relatively minor changes toward soybeans, sorghum or 
other crops due to market conditions or weather concerns.

So, in one way of looking at ethanol, one actually ought not look at the 
energy input for producing the corn, since the corn would be produced 
anyway, as long as the market is decent.  And the corn will be 
transported somewhere to be used, so that is a "SUNK COST", too, 
regardless of what use the corn is put to.  Certainly more energy will 
be expended in sending midwestern corn to 3rd world consumers than in 
dumping it at local ethanol mills.

The real problem as I see it is the disgraceful support of an erroneous 
ill-fated lifestyle by diverting foodstuffs to fuel.

However one expresses the outcome, be it in terms of the burden of wrath 
brought in by iniquity and injustice, in terms of  bad karma, or in 
terms ecologic and economic collapse, widespread famine, sociopolitical 
disquietudes, wars, and pestilences -- one thing is clear -- the Western 
world and the USA in particular is not living in a sustainable way. 
/Xindaihua/ (modernization) is taking the Chinese down a similar path 
although they might miss the bulk of the wrath because they are closer 
to the land than urban dwelling Westerners.

Americans shun close living circumstances.  Its understandable since so 
many Americans tend to be foul smelling and ill-humoured.  They prefer 
the unbroken monotony of labyrinthine farmland-eating Suburbia to the 
close-neighbors urban monotony of highrise housing, and distant shopping 
centers and discount stores to nearby markets and they enforce it with 
zoning laws so they can waste time and gasoline fighting traffic in 
their individualized mobility to get to WalMart, Target, Meijer and Costco.

Not only will we be forced by the laws of natural science and economics 
to halt the stupid wars of aggression whether our handlers want that or 
not, we will also be forced to change the way that we live.  Actually if 
we can manage to consider our ways, stop the war right away and change 
our lifestyles right away we might even get a chance to have some say in 
the outcome and how it comes about.

If we end up taking it the hard way via some sort of series of sinkhole 
socioeconomic collapses that make 9/11 and the 1930's look like a pimple 
in comparison,  we won't have much time for any real planning on the way 
down other than looking for a soft rock to crash on.

That might be a harsh analysis for a sunday afternoon but probably not 
too far from a reasonable projection.  Maybe it doesnt have to be like that.





E. Wayne Johnson wrote:
> If corn is consumed by a monogastric animal or by a human, the 
> conversion of its gross energy occurs at an efficiency of about 89%.
>
> If the corn is converted to ethanol and DDGS,  the following balance 
> seems to be a good estimate of the process.
>
> 448000 BTU          Gross energy of 56 Lb of Corn
> 210000 BTU          Gross energy of 2.7 gallons ethanol derived from 
> 56 lb corn
> 136000 BTU          Gross energy remaining in 17 lb of DDGS (wet)
> 101000 BTU          Gross energy lost per bushel in conversion to ethanol
>
> 77%   -  Efficiency of conversion of corn energy by process.
>
> <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal 
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> mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} 
> div.Section1 {page:Section1;} --> 162000 BTU          Energy to 
> process corn and distill the ethanol (according to Pimentel, 2005)
>
> 210000-162000 = 48,000 BTU net from 1 bushel corn  (plus 136 KBTU in 
> wet DDGS)
>
> 48000/124000 => Energy yield from 1 bushel corn is equivalent to 0.39 
> gallons of gasoline
>
> 110 bushels per acre (average US corn yield)
>
>
>
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>
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