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Bruce Hamilton · Guest

Repeating Decimal <salmonfry@sbcglobal.net> wrote:
[quote]Aside from the cost in money, I would like to know if the cost in energy to
produce the alcohol was greater than the enery in the alcohol. If you get
more out than then you put in, what is the rate of profit as measured in
energy? I have the gut feeling that this alcohol process was just a way to
convert fossil fuel into fresh alcohol.
[/quote]
No. The following is abstracted from an old thread. The references at the
end have quite a bit of data about the costs. The energy balance is always
controversial, and usually depends on the assumptions used. Recently, the
alcohol car fleet in Brazil has decreased from the peak, resulting in the
alcohol content of the fuel being increased to 24% to avoid a surplus, and
consideration given to blending it into diesel.

Bruce Hamilton

From: srgxbhh@grv.grace.cri.nz (srgxbhh@grv.grace.cri.nz)
Subject: Re: Alcohol fuel
Newsgroups: sci.energy
Date: 1994-05-13 11:34:04 PST

In Article <1994May8.222916.27437@selway.umt.edu>
esact@selway.umt.edu (Anthony C Tweedale) writes:
[quote]In article <2q4m4h$s0v@netnews.upenn.edu>,
Joy Morgenstern <morgenst@dolphin.upenn.edu> wrote:
The Brazilians use ethanol because
Brazil has the right climate for growing sugar cane, and the sugar
cane waste is used to make alcohol, but even there the cost of producing
ethanol from sugar cane waste is a lot higher than the cost of producing
gasoline.
except that they>ve started to produce electricity from burning the residue,
which reverses the economics.
[/quote]
No it doesn>t. The economic aspects of alcohol fuels have always
been tied to either import substitution, energy independance, or
environmental gains. There is no current alcohol fuels programme
that is economically competitive with crude oil at $16/bbl, and
Brazil failed to achieve anything like the crude oil substitution
they hoped for, because they still had to import crude to make diesel
( or import diesel itself ). Brazil has a gasoline surplus because
they didn>t implement a "whole barrel" alternatives programme,
and thus the surplus gasoline is exported.

In fact, because of the huge subsidies given to the sugar cane alcohol
producers to install facilities, there is 4+ billion gallon production
capacity and only 3 billion gallon production. The crushed cane stalk
provides most of the process energy, and the production of electricity
doesn>t significantly affect the economics of the alcohol production.

The Brazilian alcohol fuels programme along with the whole fuel and
transportation industries are strongly government regulated. The
new cars are _required_ to use ethanol. If the market was freely
allowed to choose, alcohol fuels would disappear - they are _not_
cost competitive with gasoline from crude oil at $25/bbl, much less
the current $16/bbl. The use of ethanol as an oxygenate adds extra
value to the ethanol, and that 1 billion+ production capacity can
provide ethanol to US coastal regions at costs that are competitive
with methyl tertiary butyl ether (MTBE), however the US has high
import tax duties on ethanol. With the advent of the US Clean Air
Act it was expected that biomass ethanol would capture most of the
oxygenate market, but in fact MTBE was preferred, in part
because it had more desirable properties and production could
be controlled by the producers, but mostly because it was lower
cost.

Brazilian production costs at the distillery are estimated to be
about $0.80/gallon, while US production costs ( from corn ) are
about $1.20-$1.30/gallon. The US corn based ethanol is just about
competitive with MTBE as a oxygenate additive, but falls far short
of the low price required to match the hydrocarbon gasoline.
The sugarcane yield of alcohol is about double that of corn per
unit of land. The US fuel ethanol market only exists because of
the combination of federal and state subsidies. The federal subsidy
is $0.54/gallon and various states add $0.08(Mich)-$0.29(Tenn)/gallon.

The US wholesale price of gasoline is about $0.65/gallon, and remember
that net heating values are 32MJ/L for gasoline and 21.2MJ/L for
ethanol, so more fuel is required for the same amount of power. Yes,
I recognise that some alcohol engines are slightly more efficient,
but they don>t make up even half the difference.

For those that are interested in alcohol fuels, there is a fairly
good chapter, ( called Alcohol Fuels ) in the 4th Edition of the
Kirk Othmer Encyclopedia of Chemical Technology. There is far more
technical and economic information in the proceedings of the
"International Symposium on Alcohol Fuels " held every two years.
The tenth was held at Colorado Springs 7-10 Nov 1993, and the
above are from " Ethanol Supply and Policy for the Western
Hemisphere" N.Rask & K.Rask, "The economic Characteristics of
the U.S. Fuel Ethanol Market" K.Rask, and "The Production of Ethanol
in Brazil: A good business to the biggest companies, A medium
business to Brazil" M.Sinicio & S.Bajay, presented at that
Symposium..

Bruce Hamilton

Who is wondering if it really is a mis-information superhighway.

Roland Paterson-Jones · Guest

"Bruce Hamilton" <B.Hamilton@irl.cri.nz> wrote in message
news:dkquivcr6hpsn8elbl82oqqj7apin3us86@4ax.com...
[quote]From: srgxbhh@grv.grace.cri.nz (srgxbhh@grv.grace.cri.nz)

The Brazilian alcohol fuels programme along with the whole fuel and
transportation industries are strongly government regulated. The
new cars are _required_ to use ethanol. If the market was freely
allowed to choose, alcohol fuels would disappear - they are _not_
cost competitive with gasoline from crude oil at $25/bbl, much less
the current $16/bbl.
...
Brazilian production costs at the distillery are estimated to be
about $0.80/gallon.
[/quote]
In 1994 (the time of the above posting), crude oil cost $16/bbl, and raw
sugar cost about $0.12/lb (i.e. $0.26/kg).

Times have changed. In 2004, crude oil costs $30/bbl and raw sugar costs a
touch above $0.07/lb (i.e. $0.15/kg).

I wonder if $25/bbl was the tipping point for 1994 sugar prices? If so, then
a naive linear approximation would put the 2004 tipping point (sugar at
$0.07 vs. $0.12/lb) at about $14.50/bbl crude oil. That oil price aint gonna
happen anytime soon.

The ethanol price in the above article is cheaper than expected:

From the fermentation equation, C12H22O11 + ... ->...-> 4 C2H5OH + ...,
342kg of sugar produces 46*4 = 192kg ethanol.

Now, 1 US gallon ethanol is 3.8l, or 3.8l*0.82kg/l = 3.1kg ethanol, which
required 3.1*342/192 = 5.5kg sugar. In 1994 the sugar alone would have cost
$0.26 * 5.5 = $1.43.. However, the article above reckons that the production
costs are about $0.80/gallon. Either my sums are wrong, or they are using a
cheaper source of raw materials than the world raw sugar price.

Roland

David T. Croft · Guest

Thank you for explaining carbon dating. your explanation is consistent with
my understanding except I don>t think the carbon 14 comes from carbon. It
comes from nitrogen. This being the case, the concentration of carbon 14
should depend on the concentration of nitrogen and not on the concentration
of carbon (or CO2). This, therefore, provides a means of obtaining
information about the age of the CO2 in the atmosphere. If a significant
portion of the carbon in the CO2 is old then the relative abundance of
carbon 14 should be lower than expected. It is my understanding that one of
the assumptions on which the theory of carbon dating is based is that the
ratio of carbon 14 and carbon 12 in the atmosphere is constant. If the
atmospheric concentration of CO2 is being altered significantly due to the
introduction of "old" CO2 from burning fossil fuels carbon dating becomes
less accurate.

One way to test whether there is a significant increase in atmospheric CO2
levels is to test the validity of carbon dating techniques. In rough,
simplified and not properly qualified terms:

If carbon dating still works than any changes in atmospheric CO2
concentration is NOT due to burning fossil fuels.

Now to qualify: (1) carbon dating will still "work" it will be less precise
(2) obviously some CO2 comes from fossil fuel burning; the question is how
much.

I read from a link provided above that tree rings were carbon dated in an
attempt to determine where the CO2 in the atmosphere came from. We know
that there is one tree ring per year so what was being tested was carbon
dating itself. The results over a 100 year period were reported to be off
by 2%.

Does this result imply that the concentration increase in CO2 over the last
100 years due to burning of fossil fuels is near 2%?

"daestrom" <daestrom@twcny.rr.com> wrote in message
news:xcCXa.32016$I_3.10838@twister.nyroc.rr.com...
[quote]
"David T. Croft" <dtchlc@comcast.net> wrote in message
news:GYudnelN84v-FbOiXTWJkA@comcast.com...
A though on finding out where the CO2 comes from...

If there is a significant amount of CO2 from fossil fuel burning
wouldn>t
that invalidate carbon dating results?

I read from a link provided above that tree rings were carbon dated in
an
attempt to determine where the CO2 in the atmosphere came from. We know
that there is one tree ring per year so what was being tested was carbon
dating itself. The results over a 100 year period were reported to be
off
by
2%.

I>m no expert in counting tree rings or in carbon dating but 2% is
pretty
small and leaves me wondering if it is less than the experimental error.
It
doesn>t seem right that there should be absolutely no increase in CO2
levels
over the past 100 years.

Carbon dating doesn>t use the amount of CO2 found in the biological
sample,
but the isotopic ratios of various carbon isotopes. It is known the
carbon
in CO2 is activated to a radioactive isotope by exposure to cosmic
radiation.
[/quote]
I thought it was dependent on the concentration of nitrogen, N -> 14C. If
carbon 14 came from carbon 12 it would have to gain two neutrons. The
concentration of carbon 14 should be independent of the concentration of
CO2.

[quote]This generation of carbon-14 as a percentage of the total carbon
is not dependent on the concentration of CO2 (i.e. the same percentage is
converted regardless of the total CO2 concentration in the air).
[/quote]

[quote]
Thus, plants (and indirectly animals) have a determinable ratio of
carbon-14
to carbon-12 in their 'diet'. And allowing for some decay, the ratio of
carbon-14 to carbon-12 in their bodies can be determined. By measuring
this
ratio, not the absolute concentration, carbon dating can determine when
the
animal stopped taking in carbon.

With very long lived plants like some trees, it gets tricky. The
cellulose
in the interior rings may have been formed hundreds of years ago. The
carbon-14 in this cellulose decays and is not replenished.

daestrom

[/quote]

Bruce Hamilton · Guest

On Tue, 5 Aug 2003 16:19:38 +0200, "Roland Paterson-Jones"
<roland@rolandpj.com> wrote:

[quote]"Bruce Hamilton" <B.Hamilton@irl.cri.nz> quoted
the Brazilians use ethanol because Brazil has the right climate for
growing sugar cane, and the sugar cane waste is used to make alcohol,
but even there the cost of producing ethanol from sugar cane waste
is a lot higher than the cost of producing gasoline.
In 1994 the sugar alone would have cost
$0.26 * 5.5 = $1.43.. However, the article above reckons that the production
costs are about $0.80/gallon. Either my sums are wrong, or they are using a
cheaper source of raw materials than the world raw sugar price.
[/quote]
As the article I quoted noted, they used sugarcane waste.

Bruce Hamilton

Repeating Decimal · Guest

So I am still looking for a bottom line answer to my questions: Which of the
alcohol fuel programs are not merely converting fossil fuel into alcohol?
What is the energy profit rate?

Bill

Steve Spence · Guest

when we were using corn, we were getting 2.3 times the fuel out that we put
in (distillation only). we also ran the tractors on the corn oil as well, so
effectively it was closer to 4x. Since the leftover mash was feeding the
pigs, we picked up another couple of points, making it about 6x.

--
Steve Spence
www.green-trust.org
"Repeating Decimal" <salmonfry@sbcglobal.net> wrote in message
news:BB5558CF.667D%salmonfry@sbcglobal.net...
[quote]So I am still looking for a bottom line answer to my questions: Which of
the
alcohol fuel programs are not merely converting fossil fuel into alcohol?
What is the energy profit rate?

Bill
[/quote]

William David Thweatt · Guest

David T. Croft (dtchlc@comcast.net) wrote:
: Thank you for explaining carbon dating. your explanation is consistent with
: my understanding except I don>t think the carbon 14 comes from carbon. It
: comes from nitrogen. This being the case, the concentration of carbon 14
: should depend on the concentration of nitrogen and not on the concentration
: of carbon (or CO2). This, therefore, provides a means of obtaining
: information about the age of the CO2 in the atmosphere. If a significant
: portion of the carbon in the CO2 is old then the relative abundance of
: carbon 14 should be lower than expected. It is my understanding that one of
: the assumptions on which the theory of carbon dating is based is that the
: ratio of carbon 14 and carbon 12 in the atmosphere is constant. If the
: atmospheric concentration of CO2 is being altered significantly due to the
: introduction of "old" CO2 from burning fossil fuels carbon dating becomes
: less accurate.

I think this can be corrected by adjusting for the levels of CO2 in the
atmosphere due to fossil fuel burning.

--
--
William "Dave" Thweatt
Robert E. Welsh Postdoctoral Fellow
Chemistry Department
Rice University
Houston, TX
thweatt@ruf.rice.edu
dave.thweatt@us.army.mil

João Antonio · Guest

Is it possible to say, as a rule-of-thumb:

That whenever you use a fuel froma renovable source,
I mean vegetable oil or alcohol from fermentation, the main power
input is made by the sun. It is possible to extract vegetable oils
and esterify them to get 'biodiesel" without burning fossil fuels,
even though we do this in some stages because it helps the
process.

Is that right?

"Steve Spence" <sspence@green-trust.org> escreveu na mensagem
news:3f2f86ba$1_3@newsfeed...
[quote]when we were using corn, we were getting 2.3 times the fuel out that we
put
in (distillation only). we also ran the tractors on the corn oil as well,
so
effectively it was closer to 4x. Since the leftover mash was feeding the
pigs, we picked up another couple of points, making it about 6x.

--
Steve Spence
www.green-trust.org
"Repeating Decimal" <salmonfry@sbcglobal.net> wrote in message
news:BB5558CF.667D%salmonfry@sbcglobal.net...
So I am still looking for a bottom line answer to my questions: Which of
the
alcohol fuel programs are not merely converting fossil fuel into
alcohol?
What is the energy profit rate?

Bill

[/quote]

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Roland Paterson-Jones · Guest

"João Antonio" <jas_bomfim@uol.com.br> wrote in message
news:bgtkg7$ktj$1@news.mc.ntu.edu.tw...
[quote]Is it possible to say, as a rule-of-thumb:

That whenever you use a fuel froma renovable source,
I mean vegetable oil or alcohol from fermentation, the main power
input is made by the sun. It is possible to extract vegetable oils
and esterify them to get 'biodiesel" without burning fossil fuels,
even though we do this in some stages because it helps the
process.

Is that right?
[/quote]
Joao, I think the accusation of fossil fuel dependence comes in when
fertilizers, pesticides. irrigation, and mechanical tilling, sowing and
reaping are used (i.e. modern commercial agriculture). It takes energy to
manufacture fertilizers and pesticides, for example.

Sure, the plant uses the sun>s energy to produce its sugar or oil, but you
may need to spend an awful amount of energy to maintain an environment
allowing the plant to grow.

Roland

--
Roland and Lisa Paterson-Jones
Forest Lodge, Stirrup Lane, Hout Bay
http://www.rolandpj.com/forest-lodge
mobile: +27 72 386 8045
e-mail: forest-lodge@rolandpj.com

[quote]
"Steve Spence" <sspence@green-trust.org> escreveu na mensagem
news:3f2f86ba$1_3@newsfeed...
when we were using corn, we were getting 2.3 times the fuel out that we
put
in (distillation only). we also ran the tractors on the corn oil as
well,
so
effectively it was closer to 4x. Since the leftover mash was feeding the
pigs, we picked up another couple of points, making it about 6x.

--
Steve Spence
www.green-trust.org
"Repeating Decimal" <salmonfry@sbcglobal.net> wrote in message
news:BB5558CF.667D%salmonfry@sbcglobal.net...
So I am still looking for a bottom line answer to my questions: Which
of
the
alcohol fuel programs are not merely converting fossil fuel into
alcohol?
What is the energy profit rate?

Bill

---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.507 / Virus Database: 304 - Release Date: 4/8/2003

[/quote]

Mike Darrett · Guest

"João Antonio" <jas_bomfim@uol.com.br> wrote in message news:<bgtkg7$ktj$1@news.mc.ntu.edu.tw>...
[quote]Is it possible to say, as a rule-of-thumb:

That whenever you use a fuel froma renovable source,
I mean vegetable oil or alcohol from fermentation, the main power
input is made by the sun. It is possible to extract vegetable oils
and esterify them to get 'biodiesel" without burning fossil fuels,
even though we do this in some stages because it helps the
process.

Is that right?
[/quote]

vegetable oil and alcohol: you have energy requirements for:

- planting (unless you rely on cheap labor; even then you have to feed
the laborers, ha, ha, ha)
- watering (have to supply energy to pump the water - usually done at
night, when electric costs are cheaper; or, to dig irrigation canals
[farm machinery])
- fertilizer (making it: Haber Bosch process is energy-intensive; also
have to drive farm machinery to apply it)
- pesticides (both making it and applying it)
- harvesting (again, farm machinery)
- separation / purification

- ethanol production: you have to distill out the ethanol, PLUS break
the 95% azeotrope (whoopee... calcium oxide? takes energy to make
that too...)

- biodiesel production: you need ethanol or methanol, PLUS sodium
hydroxide (a very energy-intensive electrolysis process)

Bill Vajk · Guest

João Antonio wrote:

[quote]Is it possible to say, as a rule-of-thumb:

That whenever you use a fuel froma renovable source,
I mean vegetable oil or alcohol from fermentation, the main power
input is made by the sun.
[/quote]
As it is (was) for fossil fuels.

[quote]It is possible to extract vegetable oils
and esterify them to get 'biodiesel" without burning fossil fuels,
even though we do this in some stages because it helps the
process.

Is that right?
[/quote]
There has been a flap about processing turkey guts into
oil. Diesel engines will burn all flammable oils that
they>re capable of atomizing. If some oil doesn>t want
to burn under compression alone then either glow plugs
and be added or a second chemical substance with a lower
flash point can be injected.

Processing biological products into petroleum resembling
oils is going to have costs/consequences. In an anaerobic
digester bacteria do a very nice job of converting most
things to methane which can be burned easily in stationary
engines converting garbage to electricity which frees up
some of the fuels currently allocated to producing
electricity.

In the alternative compressed methane nicely makes LNG
which is what San Diego uses to run their municipal
busses.

Put a microbe (or millions) to work for you today!

Roland Paterson-Jones · Guest

"Mike Darrett" <mike-nospam@darrettenterprises.com> wrote in message
news:d945119c.0308071416.19ffa643@posting.google.com...
[quote]"João Antonio" <jas_bomfim@uol.com.br> wrote in message
news:<bgtkg7$ktj$1@news.mc.ntu.edu.tw>...
Is it possible to say, as a rule-of-thumb...the main power
input is made by the sun.

vegetable oil and alcohol: you have energy requirements for:

- planting (unless you rely on cheap labor; even then you have to feed
the laborers, ha, ha, ha)
- watering (have to supply energy to pump the water - usually done at
night, when electric costs are cheaper; or, to dig irrigation canals
[farm machinery])
- fertilizer (making it: Haber Bosch process is energy-intensive; also
have to drive farm machinery to apply it)
- pesticides (both making it and applying it)
- harvesting (again, farm machinery)
- separation / purification

- ethanol production: you have to distill out the ethanol, PLUS break
the 95% azeotrope (whoopee... calcium oxide? takes energy to make
that too...)

- biodiesel production: you need ethanol or methanol, PLUS sodium
hydroxide (a very energy-intensive electrolysis process)
[/quote]
Mike, you>re obviously from the US intensive agriculture mentality, where
you force crops on unwilling land.

As to your points above:
1. planting - once per season
2. watering - natural cane sugar plantations have no artificial
irrigation
3. fertilizer - not needed in great amounts in the natural cane sugar
fields of Brazil or Mozambique, for example.
4. pesticides - ditto

Harvesting, sure is mechanized nowadays. Why and what is the 95% azeotrope
that we have to break?

Roland

--
Roland and Lisa Paterson-Jones
Forest Lodge, Stirrup Lane, Hout Bay
http://www.rolandpj.com/forest-lodge
mobile: +27 72 386 8045
e-mail: forest-lodge@rolandpj.com

Repeating Decimal · Guest

in article d945119c.0308071416.19ffa643@posting.google.com, Mike Darrett at
mike-nospam@darrettenterprises.com wrote on 8/7/03 3:16 PM:

[quote]"João Antonio" <jas_bomfim@uol.com.br> wrote in message
news:<bgtkg7$ktj$1@news.mc.ntu.edu.tw>...
Is it possible to say, as a rule-of-thumb:

That whenever you use a fuel froma renovable source,
I mean vegetable oil or alcohol from fermentation, the main power
input is made by the sun. It is possible to extract vegetable oils
and esterify them to get 'biodiesel" without burning fossil fuels,
even though we do this in some stages because it helps the
process.

Is that right?

vegetable oil and alcohol: you have energy requirements for:

- planting (unless you rely on cheap labor; even then you have to feed
the laborers, ha, ha, ha)
- watering (have to supply energy to pump the water - usually done at
night, when electric costs are cheaper; or, to dig irrigation canals
[farm machinery])
- fertilizer (making it: Haber Bosch process is energy-intensive; also
have to drive farm machinery to apply it)
- pesticides (both making it and applying it)
- harvesting (again, farm machinery)
- separation / purification

- ethanol production: you have to distill out the ethanol, PLUS break
the 95% azeotrope (whoopee... calcium oxide? takes energy to make
that too...)

- biodiesel production: you need ethanol or methanol, PLUS sodium
hydroxide (a very energy-intensive electrolysis process)
[/quote]
IIRC there once was talk of converting petroleum to FOOD, especially protein
food. It sounded pretty silly until it was pointed out that it typically
took more petroleum energy to grow the food than could possibly be obtained
from the food grown. I suppose we could go back to the days when more than
90% of people were serfs and the remainder kept the serfs in line or made
sure that your serfs were able to provide for you in better fashion than the
serfs of the people trying to steal your land.

Being a hobby gardener, I am sure I do not HAVE to grow my own food.

Bill

Steve Spence · Guest

yes, that>s correct. although a fossil fuel is not necessary, just
convenient to some.

--
Steve Spence
www.green-trust.org
"João Antonio" <jas_bomfim@uol.com.br> wrote in message
news:bgtkg7$ktj$1@news.mc.ntu.edu.tw...
[quote]Is it possible to say, as a rule-of-thumb:

That whenever you use a fuel froma renovable source,
I mean vegetable oil or alcohol from fermentation, the main power
input is made by the sun. It is possible to extract vegetable oils
and esterify them to get 'biodiesel" without burning fossil fuels,
even though we do this in some stages because it helps the
process.

Is that right?

"Steve Spence" <sspence@green-trust.org> escreveu na mensagem
news:3f2f86ba$1_3@newsfeed...
when we were using corn, we were getting 2.3 times the fuel out that we
put
in (distillation only). we also ran the tractors on the corn oil as
well,
so
effectively it was closer to 4x. Since the leftover mash was feeding the
pigs, we picked up another couple of points, making it about 6x.

--
Steve Spence
www.green-trust.org
"Repeating Decimal" <salmonfry@sbcglobal.net> wrote in message
news:BB5558CF.667D%salmonfry@sbcglobal.net...
So I am still looking for a bottom line answer to my questions: Which
of
the
alcohol fuel programs are not merely converting fossil fuel into
alcohol?
What is the energy profit rate?

Bill

---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.507 / Virus Database: 304 - Release Date: 4/8/2003

[/quote]

Steve Spence · Guest

That is incorrect. Chemical fertilizers and pesticides are not necessary.
nor is irrigation. all our crops are chemical free, and used no fossil fuels
for planting, growing, or harvesting. Your climate may differ.

74.7 W, 44.8 N

--
Steve Spence
www.green-trust.org
"Roland Paterson-Jones" <roland@rolandpj.com> wrote in message
news:3f327271$0$231@hades.is.co.za...
[quote]"João Antonio" <jas_bomfim@uol.com.br> wrote in message
news:bgtkg7$ktj$1@news.mc.ntu.edu.tw...
Is it possible to say, as a rule-of-thumb:

That whenever you use a fuel froma renovable source,
I mean vegetable oil or alcohol from fermentation, the main power
input is made by the sun. It is possible to extract vegetable oils
and esterify them to get 'biodiesel" without burning fossil fuels,
even though we do this in some stages because it helps the
process.

Is that right?

Joao, I think the accusation of fossil fuel dependence comes in when
fertilizers, pesticides. irrigation, and mechanical tilling, sowing and
reaping are used (i.e. modern commercial agriculture). It takes energy to
manufacture fertilizers and pesticides, for example.

Sure, the plant uses the sun>s energy to produce its sugar or oil, but you
may need to spend an awful amount of energy to maintain an environment
allowing the plant to grow.

Roland

--
Roland and Lisa Paterson-Jones
Forest Lodge, Stirrup Lane, Hout Bay
http://www.rolandpj.com/forest-lodge
mobile: +27 72 386 8045
e-mail: forest-lodge@rolandpj.com

"Steve Spence" <sspence@green-trust.org> escreveu na mensagem
news:3f2f86ba$1_3@newsfeed...
when we were using corn, we were getting 2.3 times the fuel out that
we
put
in (distillation only). we also ran the tractors on the corn oil as
well,
so
effectively it was closer to 4x. Since the leftover mash was feeding
the
pigs, we picked up another couple of points, making it about 6x.

--
Steve Spence
www.green-trust.org
"Repeating Decimal" <salmonfry@sbcglobal.net> wrote in message
news:BB5558CF.667D%salmonfry@sbcglobal.net...
So I am still looking for a bottom line answer to my questions:
Which
of
the
alcohol fuel programs are not merely converting fossil fuel into
alcohol?
What is the energy profit rate?

Bill

---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.507 / Virus Database: 304 - Release Date: 4/8/2003

[/quote]


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