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takes 1.5 gallons gasoline to produce 1 gallon ethanol in modern agriculture
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Dan Bloomquist
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Joined: 05 May 2005
Posts: 94

PostPosted: Wed Jul 12, 2006 5:29 pm    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modern agriculture Reply with quote

Eeyore wrote:

Quote:

a_plutonium@hotmail.com wrote:


But here in the USA with our petrol
based farming, we spend about 1.5 gallons of petrol just to get 1
gallon of ethanol.

Thta is simply plain wrong.

The consensus is an EROEI of 1.3
http://www.energybulletin.net/14849.html

We produce about a third of a quad of ethanol/year so net about a
tenth/year.

In 2002 we demanded 40 quad of oil.
http://eed.llnl.gov/flow/02flow.php

This is the real issue. Crop fuels have no meaningful impact.

--
"We need an energy policy that encourages consumption"
George W. Bush.

"Conservation may be a sign of personal virtue, but it is not a
sufficient basis for a sound, comprehensive energy policy."
Vice President Dick Cheney
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Eeyore
science forum beginner


Joined: 22 Jun 2006
Posts: 31

PostPosted: Wed Jul 12, 2006 8:00 pm    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modernagriculture Reply with quote

Dan Bloomquist wrote:

Quote:
Eeyore wrote:

a_plutonium@hotmail.com wrote:

But here in the USA with our petrol
based farming, we spend about 1.5 gallons of petrol just to get 1
gallon of ethanol.

Thta is simply plain wrong.

The consensus is an EROEI of 1.3
http://www.energybulletin.net/14849.html

You can argue over the numbers as much as you like. I've also seen figures using
best up-to-date practice that show EROEI of > 2 btw. I fail understand why
decisions should be made on 1980's results when better is currently available.

You could use the same principle to find fault with almost any energy source.

In any case, the energy required simply doesn't all come from oil. This is a
disingenuous tactic used by the naysayers.

Graham
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Dan Bloomquist
science forum addict


Joined: 05 May 2005
Posts: 94

PostPosted: Wed Jul 12, 2006 8:59 pm    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modernagriculture Reply with quote

Eeyore wrote:

Quote:

Dan Bloomquist wrote:


Eeyore wrote:


a_plutonium@hotmail.com wrote:


But here in the USA with our petrol
based farming, we spend about 1.5 gallons of petrol just to get 1
gallon of ethanol.

Thta is simply plain wrong.

The consensus is an EROEI of 1.3
http://www.energybulletin.net/14849.html


You can argue over the numbers as much as you like. I've also seen figures using
best up-to-date practice that show EROEI of > 2 btw.

Cite?


Quote:
I fail understand why
decisions should be made on 1980's results when better is currently available.

References
1. M. A. Delucchi, in Institute of Transportation Studies. (University
of California, Davis, 2004) pp pp. 25.
.. 2. T. Patzek, Critical Reviews in Plant Sciences 23, 519 (2004, 2004).
3. D. Pimentel, T. Patzek, Natural Resources Research 14, 65 (March
2005, 2005).
4. H. Shapouri, J. A. Duffield, A. Mcaloon, paper presented at the Corn
Utilization and Technology
Conference, Indianapolis, June 7 7-9 2004.
5. M. Graboski, “Fossil Energy Use in the Manufacture of Corn Ethanol”
(National Corn Growers
Association, 2002).
6. M. Wang, “Development and Use of GREET 1.6 Fuel Fuel-Cycle Model for
Transportation Fuels and
Vehicle Technologies” Tech. Report No. ANL/ESD/TM TM-163 (Argonne
National Laboratory, Center
for Transportation Research, 2001).
7. M. E. Dias De Oliveira, B. E. Vaughan, E. J. J. Rykiel, BioScience
55, 593 (July, 2005).

I don't see anything from the eighties here.

Quote:
You could use the same principle to find fault with almost any energy source.

I'm just going with the numbers. If you think numbers are a bad principle...

Quote:
In any case, the energy required simply doesn't all come from oil. This is a
disingenuous tactic used by the naysayers.

I never said that. EROEI doesn't say "energy returned on 'oil'
invested". No wonder you are confused.

I see you have snipped the point of my post, of course...

--
"We need an energy policy that encourages consumption"
George W. Bush.

"Conservation may be a sign of personal virtue, but it is not a
sufficient basis for a sound, comprehensive energy policy."
Vice President Dick Cheney
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boofreak@gmail.com
science forum beginner


Joined: 12 Jul 2006
Posts: 2

PostPosted: Wed Jul 12, 2006 10:42 pm    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modern agriculture Reply with quote

Eeyore wrote:
Quote:
a_plutonium@hotmail.com wrote:

But here in the USA with our petrol
based farming, we spend about 1.5 gallons of petrol just to get 1
gallon of ethanol.

Thta is simply plain wrong.

Graham

Unfortunately not. Most studies show the EROEI for ethanol to
hover around 1. Perhaps a little positive, perhaps a little negative.
Ethanol is never going to amount to much, and it certainly will
never come close to replacing oil as it now stands in our
economy. Oil has an EROEI of between 10-100:1.

Cellulistic ethanol is another loser, as the 'waste' is normally
plant remains that would be used or plowed back into the field.
This essentially amounts to strip-mining the soil for a short
term gain. All that biomass taken would have to be replaced in
the form of lots of fertilizers.

Fact is we're having trouble feeding the current population, there's
no way a significant amount of land is ever going to be used
for ethanol production without people starving to death.

It would make more sense to cover all of New Mexico with solar
panels. At 10% efficient at converting sunlight to electricity this
would be more efficient than growing plants to make ethanol.
Photosynthesis is < 4% efficient, and then there are the other
losses to create the ethanol.
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Eeyore
science forum beginner


Joined: 22 Jun 2006
Posts: 31

PostPosted: Wed Jul 12, 2006 11:42 pm    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modernagriculture Reply with quote

Dan Bloomquist wrote:

Quote:
Eeyore wrote:


In any case, the energy required simply doesn't all come from oil. This is a
disingenuous tactic used by the naysayers.

I never said that. EROEI doesn't say "energy returned on 'oil'
invested".

You may not but the previous poster did. Indeed many ppl seem to want to suggest that
all energy automatically has to come from oil ( or so it would seem ) ot alternatively
they find it convenient to say so to attempt to make a defective claim.

Quote:
No wonder you are confused.

Don't be silly.

Graham
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Eeyore
science forum beginner


Joined: 22 Jun 2006
Posts: 31

PostPosted: Wed Jul 12, 2006 11:44 pm    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modern agriculture Reply with quote

boofreak@gmail.com wrote:

Quote:
Eeyore wrote:
a_plutonium@hotmail.com wrote:

But here in the USA with our petrol
based farming, we spend about 1.5 gallons of petrol just to get 1
gallon of ethanol.

Thta is simply plain wrong.

Graham

Unfortunately not.

Actually yes. Read what he said !

" we spend about 1.5 gallons of petrol just to get 1 gallon of ethanol " which
is wrong on several counts actually.

Graham
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boofreak@gmail.com
science forum beginner


Joined: 12 Jul 2006
Posts: 2

PostPosted: Thu Jul 13, 2006 12:51 am    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modern agriculture Reply with quote

Eeyore wrote:
Quote:
boofreak@gmail.com wrote:

Eeyore wrote:
a_plutonium@hotmail.com wrote:

But here in the USA with our petrol
based farming, we spend about 1.5 gallons of petrol just to get 1
gallon of ethanol.

Thta is simply plain wrong.

Graham

Unfortunately not.

Actually yes. Read what he said !

" we spend about 1.5 gallons of petrol just to get 1 gallon of ethanol " which
is wrong on several counts actually.

Graham

Does this include all the sources of energy needed to
create the ethanol - the energy that goes into planting
and harvesting (and fertilizing) the crop, the energy
it takes to transport said crop to distiller, and finally the
energy required to ferment and distill? The infrastructure
cost?

Even conceding that ethanol might have a very
feeble energy return (i'll even give you 2:1) it's a complete
non-starter. You said it yourself, it will never come close
to replacing a fraction of the energy we get from oil,
and may end up increasing the cost of food.

Rather than debate ethanol we should be talking about
powerdown stategies and ways of transitioning to a lower
standard of living without imploding the economy, which
currently requires growth. It's absurd to pursue these
strategies so everyone can continue driving... it's not
going to happen.

Anyway, I'm not too concerned about this debate as I'm
quite certain once all the subsidies are removed for
ethanol production it will become apparent it's not a viable
source of energy. There will always be some ethanol and
biodiesel produced (even if at a loss) as they are such
useful fuels.. they will not allow the status quo to continue,
and you know it.
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Eeyore
science forum beginner


Joined: 22 Jun 2006
Posts: 31

PostPosted: Thu Jul 13, 2006 12:56 am    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modern agriculture Reply with quote

boofreak@gmail.com wrote:

Quote:
Eeyore wrote:
boofreak@gmail.com wrote:

Eeyore wrote:
a_plutonium@hotmail.com wrote:

But here in the USA with our petrol
based farming, we spend about 1.5 gallons of petrol just to get 1
gallon of ethanol.

Thta is simply plain wrong.

Graham

Unfortunately not.

Actually yes. Read what he said !

" we spend about 1.5 gallons of petrol just to get 1 gallon of ethanol " which
is wrong on several counts actually.

Graham

Does this include all the sources of energy needed to
create the ethanol - the energy that goes into planting
and harvesting (and fertilizing) the crop, the energy
it takes to transport said crop to distiller, and finally the
energy required to ferment and distill? The infrastructure
cost?

Read what he said FFS !!!!!

" we spend about 1.5 gallons of petrol just to get 1 gallon of ethanol " !

Graham
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Oz
science forum Guru Wannabe


Joined: 30 Apr 2005
Posts: 155

PostPosted: Thu Jul 13, 2006 7:39 am    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modern agriculture Reply with quote

boofreak@gmail.com writes
Quote:
Unfortunately not. Most studies show the EROEI for ethanol to
hover around 1. Perhaps a little positive, perhaps a little negative.
Ethanol is never going to amount to much, and it certainly will
never come close to replacing oil as it now stands in our
economy. Oil has an EROEI of between 10-100:1.

This is correct. However much energy is lost going from starch->ethanol.

Vegetable oils, however, are pretty well diesel-ready as crushed.
I posted (with zero comment, which is surprising) an analysis that
confirms a low return on energy invested for bioethanol (10-15%) vs a
very large return on oilseed rape oil (about 200%). Both still have
significant high-value feed residues for other uses.

Quote:
Cellulistic ethanol is another loser, as the 'waste' is normally
plant remains that would be used or plowed back into the field.
This essentially amounts to strip-mining the soil for a short
term gain. All that biomass taken would have to be replaced in
the form of lots of fertilizers.

This isn't actually very true. Firstly its rather easy to return the
nutrients to farms and secondly the nutrient levels in straws etc are
rather low. There would, of course, be a reduction in soil humus levels
as a quantity of residues are no longer returned to the soil. However
you should not forget the roots, which typically comprise the same
drymatter as above ground, and these are always returned.

Quote:
Fact is we're having trouble feeding the current population, there's
no way a significant amount of land is ever going to be used
for ethanol production without people starving to death.

Absolutely. Of course the result is likely to be high food prices and
thus more loss of rainforest.

Quote:
It would make more sense to cover all of New Mexico with solar
panels. At 10% efficient at converting sunlight to electricity this
would be more efficient than growing plants to make ethanol.
Photosynthesis is < 4% efficient, and then there are the other
losses to create the ethanol.

A tad expensive, but have you worked out the energy yield?
Ought to be quite impressive.

NB Actually if you allow say 200W/m^2 ave/day (including night/clouds
etc) then allow say 10% efficiency that's 20W electricity (ave). One
hectare (2.5ac) of 10,000m^2 thus generates some 200kW. New Mexico is
about 30M Ha, apply solar cells to a more reasonable 33% (!) that's 10M
Ha which could generate some 2000 M KW or 2000 GW.

Now I showed earlier that 1Ha of decent cropping should generate a
surplus of some 200GJ (incl straws) per Ha year = 6kW.

So solar cells generating 200kW easily outperforms cropping at 6kW.

Also requires little water and not too many inputs.

--
Oz
This post is worth absolutely nothing and is probably fallacious.
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a_plutonium@hotmail.com
science forum Guru


Joined: 11 Sep 2005
Posts: 1063

PostPosted: Thu Jul 13, 2006 9:17 pm    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modern agriculture Reply with quote

Dan Bloomquist wrote:
Quote:

The consensus is an EROEI of 1.3

Too many lobbyists and irrational people in this discussion.

Ethanol can be broken into 2 segments. The cost of energy of farming
the crops for ethanol production and the cost of energy at the Ethanol
Distillery to convert the crop into ethanol itself.

Trouble is I spent too much time considering only the farming costs and
spent little to no time in evaluating the Ethanol distilling or
refining costs.

So what is the cost of Natural Gas, most often used energy source to
refine ethanol in the USA MidWest. We can easily convert Natural Gas
quantity into gallons of gasoline or diesel. So, does anyone of these
Ethanol Plants in Iowa or South Dakota take up what? Take up so much
Natural Gas that every gallon of ethanol requires 1/2 gallon of
gasoline as a Natural Gas equivalent?

Keep in mind I am not dealing with the cost of gasoline or diesel in
the farm fields producing the crop. I am focused solely on the cost of
gasoline or diesel at the Ethanol Plant where the ethanol is made. And
most of these plants use Natural Gas as their energy source.
Natural-Gas is easy to make a equivalency to diesel. A given volume of
natural-gas is equivalent to a gallon of diesel.

So what is the energy cost at the Ethanol Plant. Is it that every
gallon of ethanol costs 1/2 gallon of diesel? If this is true and
accurate then those lobbyists and irrational sods might be happy and
gleeful. But they fail to recognize that the cost of producing the crop
in the farmfields has costs of gasoline and diesel.

So the countries like Brazil maybe happy to expand ethanol production
because they can farm their fields by horses and human labor and never
use any tractors. But when it comes to the Ethanol Plant in Brazil,
they have to use some form of fuel. Maybe they use the trees in Brazil
and burn the trees to convert the crop into ethanol. Maybe they use
Natural Gas and that means a cost of 1/2 gallon diesel equivalent per
every 1 gallon of ethanol produced.

So let us get this conversation and discussion on a correct and orderly
path. Let us divide the costs of ethanol production into the farm costs
and the actual Ethanol plant costs. So that my original statement that
1.5 gallons of gasoline/diesel produces only 1 gallon of ethanol can be
seen more clearly. So that if it takes 1/2 gallon of gasoline just at
the Ethanol Plant alone to produce 1 gallon of ethanol, does not leave
much room for using gasoline or diesel in the farm fields to produce a
crop.

Archimedes Plutonium
www.iw.net/~a_plutonium
whole entire Universe is just one big atom
where dots of the electron-dot-cloud are galaxies
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pomerado@hotmail.com
science forum beginner


Joined: 15 Jun 2006
Posts: 15

PostPosted: Thu Jul 13, 2006 11:24 pm    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modern agriculture Reply with quote

LongmuirG wrote:
Quote:
Dirk Bruere went off the rails:
And how do you cost in the subsidy oil gets through having to maintain a
huge military to ensure continuity of supply?

Let's see -- Japan depends on imports for ~100% of its fossil fuels,
including oil. Next time you see Japan's huge military flexing its
muscles in an oil producing country, be sure to alert the New York
Times; they like to report that kind of thing.

Japan depends on our military to keep its oil imports flowing.
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Eeyore
science forum beginner


Joined: 22 Jun 2006
Posts: 31

PostPosted: Fri Jul 14, 2006 12:47 am    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modern agriculture Reply with quote

a_plutonium@hotmail.com wrote:

Quote:
So that my original statement that
1.5 gallons of gasoline/diesel produces only 1 gallon of ethanol can be
seen more clearly.

You're just making this up as you go along you idiotic troll.

Graham
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Eeyore
science forum beginner


Joined: 22 Jun 2006
Posts: 31

PostPosted: Fri Jul 14, 2006 12:49 am    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modern agriculture Reply with quote

pomerado@hotmail.com wrote:

Quote:
LongmuirG wrote:
Dirk Bruere went off the rails:
And how do you cost in the subsidy oil gets through having to maintain a
huge military to ensure continuity of supply?

Let's see -- Japan depends on imports for ~100% of its fossil fuels,
including oil. Next time you see Japan's huge military flexing its
muscles in an oil producing country, be sure to alert the New York
Times; they like to report that kind of thing.

Japan depends on our military to keep its oil imports flowing.

Now do please exlain that gem of wisdom !

Graham
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pomerado@hotmail.com
science forum beginner


Joined: 15 Jun 2006
Posts: 15

PostPosted: Fri Jul 14, 2006 9:14 am    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modern agriculture Reply with quote

Eeyore wrote:
Quote:
pomerado@hotmail.com wrote:

LongmuirG wrote:
Dirk Bruere went off the rails:
And how do you cost in the subsidy oil gets through having to maintain a
huge military to ensure continuity of supply?

Let's see -- Japan depends on imports for ~100% of its fossil fuels,
including oil. Next time you see Japan's huge military flexing its
muscles in an oil producing country, be sure to alert the New York
Times; they like to report that kind of thing.

Japan depends on our military to keep its oil imports flowing.

Now do please exlain that gem of wisdom !

As part of the treaties that eneded WWII, Germany and Japan gave up
their offensive military capabilities. Japan previously had a Navy the
equivalent of any world power. Because of the strong America-Japan
alliance, it has been in the US interest for the US Navy to guarantee
Japan against external threat (Pax Americana).

For a current example, observe the North Korean situation. If that
comes down to the need for a military solution, whose military do you
think it is going to be?
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Eeyore
science forum beginner


Joined: 22 Jun 2006
Posts: 31

PostPosted: Fri Jul 14, 2006 9:42 am    Post subject: Re: takes 1.5 gallons gasoline to produce 1 gallon ethanol in modern agriculture Reply with quote

pomerado@hotmail.com wrote:

Quote:
Eeyore wrote:
pomerado@hotmail.com wrote:

LongmuirG wrote:
Dirk Bruere went off the rails:
And how do you cost in the subsidy oil gets through having to maintain a
huge military to ensure continuity of supply?

Let's see -- Japan depends on imports for ~100% of its fossil fuels,
including oil. Next time you see Japan's huge military flexing its
muscles in an oil producing country, be sure to alert the New York
Times; they like to report that kind of thing.

Japan depends on our military to keep its oil imports flowing.

Now do please exlain that gem of wisdom !

As part of the treaties that eneded WWII, Germany and Japan gave up
their offensive military capabilities. Japan previously had a Navy the
equivalent of any world power. Because of the strong America-Japan
alliance, it has been in the US interest for the US Navy to guarantee
Japan against external threat (Pax Americana).

Fine. Yes I'm aware of that and Japan even now simply has its self-defence force.

However the suggestion that the US militray is needed to keep Japan's oil imports
flowing is plain daft.


Quote:
For a current example, observe the North Korean situation. If that
comes down to the need for a military solution, whose military do you
think it is going to be?

Depends if China and Russia get pissed off too I reckon.

Graham
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