po prostu dotacje dla farmerow. Bioetanol to bzdura, drogi, gorszy.
Chemicy o tym wiedza, a nawiedzeni zawodowi ekolodzy nie chca slyszec. Wszak to
znakomite zrodlo dochodow.

Sure--here's some USDA estimates in KCALS to produce and harvest one
acre of corn

Labor 49000
Machinery 420000
Gas 797000
Nitrogen 940800
Phosphorus 47100
Potassium 63000
Seeds 68000
Irrigation 34000
Incecticides 11000
Herbicides 11000
Drying 120000
Electricity 330000
Transportation 70000

Total Inputs 2,896,800 Kilocalories per acre

For ethonal production corn need not be dried/Iowa farmers don't
irrigate/electric fans unnecessary saving 484,000KCAL---bringing the
total inputs to 2,412,800KCAL per acre of corn.

Some may disagree with the 2,412,800 KCAL per acre figure--and they may
be correct.The farmer for example may say--I alternate inoculated
legumes (soy beans) with corn every year. This practice fixes about
100 lbs or more usable nitrogen per acre. Also, fertilizer requirements
are diminished by returning everything back to the soil except the
seed.

So now we have the approx energy expended (2,412,800 KCALs) to plant
and harvest one acre of corn with some variance.

How many bushels of corn can be produced on this acre?

Numbers vary--record yield is over 300 bushels per acre--average is
near 150 bushels in 2005--up from 71 in 1970.

One bushel of shelled corn weighs 56 pounds--so one acre produces
150x56=8400lbs of corn--therefore the energy expended to produce one
pound of corn is 2,412,800KCAL/ 8400 or 287KCAL.

To sum to this point--it takes 287KCAL to produce one pound of corn--or
it can be purchased at the elevator for 200/56=3.57 cents

Now, how many gallons of ethyl alcohol C2H5OH (C2H60) can be made from
one bushel of corn?

Iowa State University (ISU) studies suggests that 2.5 gallons per
bushel could be produced under reasonable conditions. Recent studies
have also suggested that by treating ground corn with ultrasound, 30%
more sugar could be attained by improving the brake up of carb
molecules in the corn. For this example though, let's stick with 2.5
gallons per bushel but remember that 2.74 gallons per bushel would be
the probable limit from corn seeds only.

If one bushel of corn (56lbs) produces 2.5 gallons of ethanol--then
56/2.5= 22.4 lbs of corn will produce one gallon.

Before we start fermentation/distillation our energy/$ cost for the
corn necessary to produce one gallon of ethanol is/are:

22.4 lbs corn x 287KCAL per lb= 6428.8 KCALs (corn planted and
harvested) or22.4 lbs corn x 3.57 cent per lb= 79.96 cents (corn
purchased at elevator)

Now let's take a look at actual ethanol production process. One method
that has work successfully for years ( perhaps not the best ref energy
costs but should work for our calculations)

Finely grind the corn seeds and heat at 212 F in water for 30 minutes
to form a gelatine (or mash). The starch in the mash is cooled then
malted at 152 F(addition of ground sprouted corn--the sprouted material
contains the enzyme diastase which converts the starch to sugar.) After
the material cools to around 70 F the yeast is added--the holding
vessel is capped and fermentation begins.

Chemically, for glucose.... C6H1206----->Enzyme--->2C2H50H
(2C2H60)+2C02

In 7-10 days the yeast has coverted the sugars to ethanol and
distillation can begin.

Energy calculations remaining:
Grinding/crushing 20.9 lbs of corn (1.5 lb used for malting)
Heating solution to 212F and holding for 30 minutes
Malting (sprouting 1.5 lb of corn)
Grinding/crushing 1.5 lb of sprouts
Distillation of water and ethanol mixture
Misc--manpower, movement of fluids, etc.

It's easy to see at this point that the "devil" is in the distillation
process. Factors that will schew the outcome and resultant decision on
cost effectiveness--can be driven in a variety of directions based on
purity of the final ethanol product, the energy source used for
distillation, and the type of distillation method used (batch,
fractional, etc.)

Statements in a variety of writings suggest that an energy input
anywhere from 32,000 BTU's per gallon to---"a large industrial still
will use only one steam horsepower hour to produce twenty gallons of
alcohol"--ie 33,445.7BTUs/20 = 1672.28 BTUs per gal exist.

Before we start on the distillation energy calculations let's consider
what purity of ethanol we need. The following are a few statements
clipped from sources in 1979.

Alcohol fuel must be over 100 proof (50% ethanol/water) to burn
150 proof (75% ethanol/water) is desirable for heating purposes
170 proof (85% ethanol/water) is desirable for automotive use

Another source:

"There is no difference in power and mileage between 160 proof (80%
ethanol/water) and 200 proof (100% ethanol)...additionally, at 160
proof the 20% water appears to cool the exhaust valves..."

It would seem that some water in the combustion process might be
beneficial under certain conditions as in this example---"Water
injection is also featured on the record setting Spyder coupe owned
byTom Keosababian of Whittier, California. The car
turned 133 MPH at the 1964 Bonneville Nationals." )

Finally--what is the highest percentage of ethanol/water mixture we can
expect after the fermentation process.

Alcohol tolerance of the yeast used for fermentation and the amount of
sugar available in the solution determines the ethanol percentage.
Yeast will continue to convert sugar into ethanol as long as there is
sugar to digest and the alcohol in solution is diluted enough so that
it doesn't kill the active yeast.

Each yeast strain has a slightly different acholol tolerance--brewers
books document various strains and their probable ethanol percentage.

"It is important to understand that yeast cannot live in a solution
containing more than 14% alcohol by volume. This is the usual amount
that will destroy the yeast...but under certain circumstances, and with
suitable yeast the percentage might be as high as 18%. On the whole an
amateur is unlikely to produce more than 16%, because he is unlikely to
be able to carry out his ferment under conditions with constantly
favourable temperatures and a scientifically balanced must."

Point being--ferment to the highest possible percentage uses 15%.
Distillation of higher percentages of ethanol/water requires less
energy for any given product proof.

To save time on the distillation discussion, I call your attention
www.ces.purdue.edu/extmedia/AE/AE-117.html Titled 'ALCOHOL
DISTILLATION:BASIC PRINCIPLES, EQUIPMENT, PERFORMANCE RELATIONSHIPS,
AND SAFETY by Kvaalen, Wankat, McKenze.

Quoting from page 19 FACTORS AFFECTING ENERGY USE AND COLUMN
SIZE--"...the best way to operate is to have a good fermentation (high
alcohol content in beer)...to preheat the feed (in the condenser, if
not also with a heat exchanger). In this way. one can produce alcohol
for around 1800 BTU/pound (11,000-12000 BTU/gallon) which can be burned
without further concentration in a slightly modified gasoline engine..

Reviewing the 7-21-06 Purdue release Page 20 Table 1 shows that
11,000-12,000 BTU's/gal are required for distillation of a solution of
approx 8% ethanol/water to 90% ethanol--a 12% solution requires 1450
BTU's/lb (approx 9425 BTU's/gal.) Distillation of a 15% solution should
require about 1140 BTU's/lb (7470 BTU's/gal) for 90% (180 proof)
ethanol which the study says "can be burned without further
concentration in a slightly modified gasoline engine."

One additional note: Page 2 par 1 suggests that "...many oil
companies..add ethyl alcohol" (eth