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'[EE]:: The good oil on biofuels'
2006\12\29@035107 by Russell McMahon

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This 'report' (from a site that will be red rag to a bull to some list
members) argues that biofuels are at best nowhere near as clean and
green as they appear, and at worst are worse than not developing them
at all.

       http://ww4report.com:80/node/2864

Issues include, actual net energy gains (or not), CO2 net releases,
affects on rain forest, food crop displacement, net pollution and
more.

Some reputable sources that also add food for thought include:

University of Minnesota
"Environmental, economic, and energetic costs and benefits of
biodiesel and ethanol biofuels
Jason Hill, Erik Nelson, David Tilman, Stephen Polasky, and Douglas
Tiffany

       http://www.precaution.org/lib/biodiesel_vs_ethanol.060725.pdf

________

Cornell University
Ethanol Production Using Corn, Switchgrass, and Wood;
Biodiesel Production Using Soybean and Sunflower
David Pimentel1,3 and Tad W. Patzek2

   http://www.precaution.org/lib/ethanol_and_biodiesel.050301.pdf

>From the above, the following conclusions are worth noting:

CONCLUSION

Several physical and chemical factors limit the
production of liquid fuels such as ethanol and
biodiesel using plant biomass materials.
These include the following:

(1) An extremely low fraction of the sunlight
reaching America is captured by plants. On
average the sunlight captured by plants is
only about 01.%, with corn providing 0.25%.
These low values are in contrast to photovoltaics
that capture from 10% or more sunlight,
or approximately 100-fold more sunlight
than plant biomass. [Russell - *]

(2) In ethanol production the carbohydrates
are converted into ethanol by microbes,
that on average bring the concentration of
ethanol to 8% in the broth with 92% water.
Large amounts of fossil energy are required
to remove the 8% ethanol from the 92%
water.

(3) For biodiesel production, there are two problems:
the relatively low yields of oil crops
ranging from 1,500 kg/ha for sunflower to
about 2,700 kg/ha for soybeans; sunflower
averages 25.5% oil, whereas soybeans average
18% oil. In addition, the oil extraction
processes for all oil crops is highly energy
intensive as reported in this manuscript.
Therefore, these crops are poor producers of
biomass energy.


________

Russell says:

* - type setting suspect.
Appears to mean 0.1% average and 10% for photovoltaics.
Corn at 0.25% is 40 times worse than PV.


2006\12\29@065557 by Mohit M. (Lists)

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RM:
> the relatively low yields of oil crops
> ranging from 1,500 kg/ha for sunflower to
> about 2,700 kg/ha for soybeans; sunflower
> averages 25.5% oil, whereas soybeans average 18% oil.

Maybe the yields are slightly better with Jatropha (India) and Palm
Oil (Malaysia):
http://www.hareda.gov.in/bioenergy.htm

I am in talks with an institute here in India for collaborating on low
cost biodiesel production systems/techniques design from Jatropha.
Still early days though, and would know for sure from first hand
experience after some months (1-2 years?) maybe.

General info on Jatropha:
http://www.jatrophaworld.org/

Mohit Mahajan.

2006\12\29@133523 by Stephen R Phillips

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--- Russell McMahon <spam_OUTapptechTakeThisOuTspamparadise.net.nz> wrote:

> This 'report' (from a site that will be red rag to a bull to some
> list
> members) argues that biofuels are at best nowhere near as clean and
> green as they appear, and at worst are worse than not developing them
>
> at all.
>
>         http://ww4report.com:80/node/2864
>
> Issues include, actual net energy gains (or not), CO2 net releases,
> affects on rain forest, food crop displacement, net pollution and
> more.

Ahhh I believe a lot of people here "BioDisiel" and think "This is the
silver bullet" People seldom understand that it is merely shifting the
problem to a different one.  As I find myself oft saying 'The solution
to the problem is to change it to one you can solve.'

There is no easy answer. The other big issue is people are starving all
over, cheap food will disappear in the guise of 'cheap energy'.  I do
think there is a solution but creating a worse problem is definately
not an answer.  I would keep ones eye on the politics and be sure there
aren't any white elephants being created (a white mouse to US
government specifications).

Glad you read a lot! It keeps everyone else informed.  :D

Stephen

Stephen R. Phillips was here
Please be advised what was said may be absolutely wrong, and hereby this disclaimer follows.  I reserve the right to be wrong and admit it in front of the entire world.

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2006\12\29@134158 by Marcel duchamp

picon face
Russell McMahon wrote:

> (2) In ethanol production the carbohydrates
> are converted into ethanol by microbes,
> that on average bring the concentration of
> ethanol to 8% in the broth with 92% water.
> Large amounts of fossil energy are required
> to remove the 8% ethanol from the 92%
> water.
>

Fossil energy required? Nonsense.  Why do you assert that "Large amounts
of fossil energy are required"???

Ethanol production can certainly use ethanol for energy requirements.
Once the fermenters have started, there will be plenty of ethanol output
from which some percentage can be used where ever there are energy
requirements.  Obviously, any ethanol used to produce more ethanol will
cut the yield somewhat.

I'm also skeptical of the 8% figure but have no data one way or the
other aside from brewing experience wherein 15% is trivial to arrive at.
I have seen anecdotal evidence that suggests greater than 20% is
possible when using the proper yeast strains.

2006\12\29@145826 by Stephen R Phillips

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--- Marcel duchamp <.....marcel.duchampKILLspamspam@spam@sbcglobal.net> wrote:

>
> Fossil energy required? Nonsense.  Why do you assert that "Large
> amounts of fossil energy are required"???

Well darn I should go out and dig up some fossils ;)
>
> Ethanol production can certainly use ethanol for energy requirements.
>
> Once the fermenters have started, there will be plenty of ethanol
> output from which some percentage can be used where ever there are
> energy requirements.  Obviously, any ethanol used to produce more
> ethanol will cut the yield somewhat.
>
I would not be too excited about the yields of ethanol either though.
No matter how you look at the problem there is no EASY solution.  Bio
Fuels are merely a drop in the bucket in terms of energy.  They are not
very efficient in terms of yield.  Only thing I can think of is farmers
can remain solvent with the idea.  Ethanol is a poor fuel in terms of
useful energy as well (that little OH making it an alcohol causes a lot
of trouble with water) I'm neither for nor against biofuels however
zealousy in either direction (for or against) clouds the real problem.

> I'm also skeptical of the 8% figure but have no data one way or the
> other aside from brewing experience wherein 15% is trivial to arrive
> at. I have seen anecdotal evidence that suggests greater than 20% is
> possible when using the proper yeast strains.

Hmmmm I agree.  You can get better yields, however you must consider
the cost.  Ethanol is easily distilled using waste heat from some other
industrial concern (fossil fuel power plant for example).  I believe
the real problem with biofuels is a lack of perspective.  IE "We can
use this and save the world", whereas the truth is people have
different agendas for promoting biofuels.  Here in the US some are
attempting to use biofuels as a way to subsidize the farmers who raise
corn, by forcing a production quota for fuel (between ethanol and
traditional gasoline).  There is a place for biofuels yes, but a rapid
forceful change in things is a nice way to create a disaster.  In the
case of my area, most cars will expire very rapidly using biofuels.
85% Ethanol fuel is widely available where I live but only certain
people can use it (Ironically most agricultural machines can burn it
because of the heavy duty nature of there engines).

I agree bio fuels are useable and aren't impractical, the specifics of
what to use them for are something completely different.  An infamous
quote from the Simpsons "95% of statistics are made up", I interpret as
people will make numbers meet there agenda. It would be nice if some
people actually concentiously put some numbers out that make sense.
Attempting to baffle people with fecal excrement from a male bovine is
quite anoying (if not insulting).  What's wrong with the actual facts
and a realistic perspective? I don't know, but it seems too many have
agenda's these days.

I don't think the solution to the worlds energy issues is going to just
be biofuels however.  Certainly they are useful for a specific segment
however general use, will create very serious problems, as there simply
isn't enough agricultural land to meet the energy demand, food wise the
world is doing fine, a sudden shift in land use is something you don't
want to think about the consequences.

I believe it is best to take several small steps instead of the Fedel
Castro method of managing the problem (IE make everyone produce sugar
and wipe out most of Cuba's land for food to feed his people).

As for how this relates to Electronics, Ethanol fuel cells are
available for Cell phones.  Maybe Ethanol for simple things like that
will work? I know in the US, ethanol must be poisoned in order to be
sold as anything other than consumable alcohol (which is heavily
taxed).

Stephen

Stephen R. Phillips was here
Please be advised what was said may be absolutely wrong, and hereby this disclaimer follows.  I reserve the right to be wrong and admit it in front of the entire world.

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2006\12\29@184006 by William Chops Westfield

face picon face
On Dec 29, 2006, at 11:58 AM, Stephen R Phillips wrote:

> Bio Fuels are merely a drop in the bucket in terms of energy.
> They are not very efficient in terms of yield.  Only thing
> I can think of is farmers can remain solvent with the idea.

Yeah, it probably works out that the bio-fuel interest is actually
farming special interests having their way, and the hydrogen stuff
is the big natural gas producers hedging their bets (sources of
hydrogen for the foreseeable future come from fossil fuels), and
the fusion research is just a way of funding "big science."  All
politics (well, almost all; I don't doubt that there is some value
to each of those regardless of "real" motivation.)  Feh.  This is
the sort of thing that keeps all those "free energy" quacks in
business; it's SO easy to believe in government and big energy
conspiracies to suppress "real" solutions...

BillW

2006\12\29@193651 by Jinx
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> But *if* [[and it's moot depending on various assumptions in each
> setting]] there's an overall energy loss, then using the output to
> drive itself increases the loss per unit of output.

So what's really messing up the equation is the external fossil energy
needed to get at the biofuel. That puts forward the case for nuclear
(fission now, hopefully fusion in the future), hydro, wind, solar etc to
do that. And also reducing the demand for fuel in the first place, ie the
consumer must be more efficient. It can be done in emergencies (eg
everyone does their bit when electricity supplies are stressed). Tune
the engine, drive thoughtfully, carpool, walk when possible, public
transport etc. It's not necessarily a pipe-dream, what's needed is for
the trend to be started


2006\12\29@203106 by Russell McMahon

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> Yeah, it probably works out that the bio-fuel interest is actually
> farming special interests having their way,

Certainly a fair bit of that.
But no one objection is the sole one and all schemes have some
benefits.
Also, very importantly, food displacement is an important issue.

> and the hydrogen stuff
> is the big natural gas producers hedging their bets (sources of
> hydrogen for the foreseeable future come from fossil fuels),

Hydrogen "needs work".
If you think of it as an energy transfer medium from other energy
sources, and then concentrate on making those sources cost effective,
it will probably make sense *in time*.

BUT

> the fusion research is just a way of funding "big science."

This has much truth in it, but fusion alone offers energy sources
whose cost of resource acquisition is far far far outstripped by the
energy returns. Fusion is THE energy source of the / a future. How far
away that future is and whether we ever get to it is the/a question
:-).



       Russell


2006\12\29@203106 by Russell McMahon

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>> But *if* [[and it's moot depending on various assumptions in each
>> setting]] there's an overall energy loss, then using the output to
>> drive itself increases the loss per unit of output.

> So what's really messing up the equation is the external fossil
> energy
> needed to get at the biofuel.

It's not that it's *fossil* energy per se that neds inputting - it's
the fact (apparently) that overall the net process loses energy. If
you consider biofuel to be an energy transport medium (as hydrogen is)
and IF you have sources of energy elsewhere that are net energy
positive but not accessible, then the biofuel may be viable (eg a
methanol operated car may use solar energy produced in the Simpson (or
Sahara) desert.. If though you are looking at the biofuel as being an
energy "source" in its own rigjht there appear to be 'problems'.

'> That puts forward the case for nuclear
> (fission now, hopefully fusion in the future), hydro, wind, solar
> etc to
> do that.

The arguments are that all of these (except for fusion) are in fact
net energy negative and/or not renewable. eg Nuclear fission is
relatively exhaustible UNLESS you go to fast breeder technology with
(amongst other things) Plutonium as an output. Some like this option.
It seems to me (although the nay sayers say nay) that systems that you
mention which are essentially solar (wind, photo voltaic, solar
thermal) can have their net returns improved with improved technology.
For force based systems (wind. some thermal) this would largely have
to be done by increasing system lifetimes, reducing cost or producing
raw materials more efficiently. Actual energy conversion efficinies
are already reasonably high (eg wind turbines). Hydro is arguably
already near peak capability already both in terms of efficiency of
conversion and lifetime costs. PV still has efficiency gains possible
and new and 'cheaper' materials.

> And also reducing the demand for fuel in the first place ...

And that's another story.


   Russell.

2006\12\30@060410 by Russell McMahon

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>> the relatively low yields of oil crops
>> ranging from 1,500 kg/ha for sunflower to
>> about 2,700 kg/ha for soybeans; sunflower
>> averages 25.5% oil, whereas soybeans average 18% oil.

> Maybe the yields are slightly better with Jatropha (India) and Palm
> Oil (Malaysia):
> http://www.hareda.gov.in/bioenergy.htm

The first project on that page is a positive one ! :-)

Producing Methane "Gobar Gas" from "night soil" (animal and human
excrement) converts Methane, which is a very high GW coefficient gas,
to CO2, with a much lower  GW coefficient and along the way provides
energy and employment and more. Regardless of the merit of the GW
case, odds are that the "carbon credits" alone of such a poject may
make it worthwhile. Without use of this feedstock the MEthane would be
released to atmosphere. Making use of cattle excrement in India is a
substantial potential gain due to the cattle's otherwise potential
utilisation.


> I am in talks with an institute here in India for collaborating on
> low
> cost biodiesel production systems/techniques design from Jatropha.
       > http://www.jatrophaworld.org/


Jatropha does look like a useful plant for extracting bio energy from
very low productivity land. It would be interesting to know what if
any other crops it competes with and whether its promotion will affect
food production in any way.


       Russell


2006\12\30@102206 by Mohit M. (Lists)

picon face
> Producing Methane "Gobar Gas" from "night soil"
We do not need fuels for heating homes here in India, in fact quite
the opposite, its a hot country. It was meant primarily as a cooking
fuel. And the food is cooked in open vessels. So the food
smells/tastes quite literally like shit. :-)

> Jatropha does look like a useful plant for extracting bio energy
> from
> very low productivity land.
Yes! This institute (http://www.jatrophaworld.org/) is in an arid part
of the country, Rajasthan. Jatropha grows wild there. Apparently,
requires very little 'maintenance' or so the fellow tells me.

> It would be interesting to know what if
> any other crops it competes with and whether its promotion will
> affect
> food production in any way.
None whatsoever. The plan is to grow Jatropha on land which has no
chance of being cultivated. And to shift farmlands with low yields of
other crops to Jatropha making more sense economically.

Mohit Mahajan.

2006\12\30@111936 by Russell McMahon

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>> It would be interesting to know what if
>> any other crops it competes with and whether its promotion will
>> affect food production in any way.

> None whatsoever. The plan is to grow Jatropha on land which has no
> chance of being cultivated. And to shift farmlands with low yields
> of
> other crops to Jatropha making more sense economically.

That sounds good but even moving from low yield crops to biofuel
feedstock can have undesirable consequences. I'm not saying that it
shouldn't be done - just that the true costs need to be carefully
watched. It may increase the lowest incomes - but it may instead lead
to a decrease in living standards for those at the very bottom. The
fact that some people are cropping on very low yield land suggests
either a very low income level or the ability to produce food at a
lower price than it can be bought elsewhere. Increasing the return of
such farmers with an increased income crop may indeed put more food in
people's mouths - but it also may make bottom of the market food
dearer for those who can afford nothing else. This is more likely to
be the case if the poorest farmers are net producers and sell to
others who are also poor but not directly involved in food production.
The end result may be greater overall satisfaction at the expense of
the poorest. If "market forces" / invisible hand etc are acceptable
ways to run such decisions then all is well. But if you are a very
poor non food producer then you may not feel totally happy with the
effect on your family.


       Russell.


2006\12\30@170649 by William Chops Westfield

face picon face

> ...for extracting bio energy from very low productivity land.
>
Presumably this is the real potential of bio-fuels.  Even if the
energy payback is only 1%, if you have otherwise unusable land
that can be easily seeded and harvested for biofuels.  Current
"state-of-the-art" involves conventional techniques for farming,
fermentation, and distillation/conversion, but I don't see any
particular reason that energy efficiency of those operations
couldn't be improved a great deal (solar distillation to much
greater than 8%, etc.)

BillW

2006\12\30@173154 by Art

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I read a good part of this thread, and I'm still confused::>

No one in their right mind would consider bio-diesel or bio-fuel as a
100 percent practical answer (at least I hope people aren't that stupid::>).

But, bio-fuel/bio-diesel is practical regionally... Which, is exactly
how it is used in the US-to the best of my knowledge, it isn't used
widely in areas other than the midwest for precisely this reason.

Did I miss something, or did the group assume someone actaully
thought bio-anything was the total solution?

Art


2006\12\30@181359 by Wouter van Ooijen

face picon face
> Did I miss something, or did the group assume someone actaully
> thought bio-anything was the total solution?

Yes, of course it is the total solution! Which leaves the question to be
answered: to which problem?

Wouter van Ooijen

-- -------------------------------------------
Van Ooijen Technische Informatica: http://www.voti.nl
consultancy, development, PICmicro products
docent Hogeschool van Utrecht: http://www.voti.nl/hvu


2006\12\30@200224 by Russell McMahon

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> Yes, of course it is the total solution! Which leaves the question
> to be
> answered: to which problem?

To the special case, with exceptions, 5% to 15% fossil diesel additive
problem, of course.
:-)

       Russell



'[EE]:: The good oil on biofuels'
2007\01\04@180746 by Jinx
face picon face
www.motoring.co.za/index.php?fSectionId=1566&fArticleId=3528666

British magazine Car has been putting a few noses out of joint in the
automotive trade. Its current edition has a report from an American
outfit called CNW Marketing Research

http://cnwmr.com/nss-folder/automotiveenergy/

that puts the Toyota Prius and other hybrid models in their place by
declaring the greenest car you can buy in Britain is......a Jeep Wrangler!

The Wrangler, presumably, is pretty simple, doesn't cost much to make
and, like a number of supposedly evil SUVs, should have a very long life
because of its rugged construction.

The Wrangler is pretty simple, doesn't cost much to make and should
have a very long life

Of course Toyota doesn't see it that way

It disputes the proportion of energy used to make a car compared with
how much the vehicle uses during its life, mainly from burning fuel.

The Americans say 80 percent of the energy a car uses is accounted for
by manufacture and 20 percent in use: Toyota claims the reverse

2007\01\04@183719 by Peter P.

picon face
William "Chops" Westfield <westfw <at> mac.com> writes:

> On Dec 29, 2006, at 11:58 AM, Stephen R Phillips wrote:
>
> > Bio Fuels are merely a drop in the bucket in terms of energy.
> > They are not very efficient in terms of yield.  Only thing
> > I can think of is farmers can remain solvent with the idea.
>
> Yeah, it probably works out that the bio-fuel interest is actually
> farming special interests having their way, and the hydrogen stuff
> is the big natural gas producers hedging their bets (sources of

About alcohol:

1) Traditional alcohol production uses wood as fire source. Not even that is
needed if vacuum distillation is employed. Vacuum distillation is very energy
effective (due to the use of low temperature heat sources, like sun or waste
heat from fruit canning lines) and has a yield equal or higher to that of boil
distillation. Also there are no hot vapors to explode outside the process, and
no fire to ignite them. Note that this process requires more BTU than the normal
distillation (huh?) but at a much lower temperature. Then there is adsorbtion.
Freeze concentration is also an option (use the winter Luke). See more here:

 http://www.ces.purdue.edu/extmedia/AE/AE-117.html

1a) Heat consumption for production vs. heat of combustion is about 3x10^7J vs
1.4x10^8J.

2) Normal yield is 10+% alcohol by volume of fermented substance (no exotics
here, apples, prunes, etc rejects from the market). With the same under
continuous vacuum extraction the alcohol never reaches 14% in solution (which
kills off the yeasts) so the yield is even higher. The yeasts do not mind the
vacuum above, however it will froth 10 times more than normal.

3) Moonshine stills are NOT the way to produce alcohol. They make alcoholic
beverages etc. Also we are in the 21nd century, not the 15th.

4) Rocket fuel is not anhydrous alcohol. V2 rockets used 75% ethyl alcohol + 25%
water at a chamber pressure of 15 atm (with LOX oxydizer). They went up 180+km.
Using a higher proportion of alcohol can melt things and degenerate into
detontion mode. Current requirements for anhydrous alcohol for fuel are due to
the mixing with gasoline for E85 etc. Water in E85 causes the alcohol to
separate out. Thus 'real' alcohol fuel that permits 15:1 compression ratio is
not anhydrous (and is also cheaper than anhydrous alcohol and easier to store).

I think that the powers that be are more concerned about their tax revenue than
about other things (like untaxed inebriation) when they manipulate information
about alcohol in the media.

Anyway alcohol is not snake oil. It will not solve all the problems, but it is
one of the smaller problems. And unlike hydrogen it is not really really
dangerous or hard to handle.

Peter P.


2007\01\04@211718 by Russell McMahon

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> Of course Toyota doesn't see it that way
>
> It disputes the proportion of energy used to make a car compared
> with
> how much the vehicle uses during its life, mainly from burning fuel.
>
> The Americans say 80 percent of the energy a car uses is accounted
> for
> by manufacture and 20 percent in use: Toyota claims the reverse

Any two organisations who can get their comparative results out by a
factor of *** 16 *** , as is the case here, without being able to
clearly demonstrate that the other party is a turkey, and doing so,
are probably both cooking the figures. That said, I'd say Toyota's
claim sounds closer to reality. Perhaps both claims are true, and one
applies to Toyotas and the other to Jeeps :-)



           Russell::

2007\01\04@211718 by Russell McMahon

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> 4) Rocket fuel is not anhydrous alcohol.

It would esentially be if you used alcohol. Few rockets do nowadays.
It has some advantages but it is a relatively low performance
propellant compared to viable alternatives. eg even LOX and Kerosene*
has substantially superior performance. (* "Jetex" and "RPx" and
similar are special kerosenes chosen for their relative purity and
absence of fractions which polymerise when heated and goo up your
injectors and chamber).

> V2 rockets used 75% ethyl alcohol + 25% water

This was mainly to lower the combustion chamber temperature to suit
the materials used. It also helped a relatively rare resource go
further. It also didn't overly hurt net performance in this
application but modern methods tend (not always wisely) to optimise
performance. [[Truax et al BDB** approach compared with systems like
eg STS/Shuttle]]

> And unlike hydrogen it is not really really dangerous or hard to
> handle.

Unless you drink it (whether 85% or anhydrous).
But, then, liquid Hydrogen is also dangerous to drink, and has no
taste that you will ever taste if you do :-)



       Russell
       (*REAL* men drink slush-Hydrogen).


** BDB = Big Dumb Booster.
High relative performance is replaced by low tech, low cost, ease of
design and manufacture and shorter time to market leading to BIG but
cheap first stages in particular.  NASA hasn't fully 'got it' yet,
alas. Truax was doing this in 1958.
"Just because they won't listen doesn't mean you are wrong" :-).
Gargoyle
       robert truax sea dragon ....
Not to mention
       snake river evil knievel <sp?>  steam rocket ...



2007\01\05@035945 by Alan B. Pearce

face picon face
>The Wrangler is pretty simple, doesn't cost much to
>make and should have a very long life
>
>Of course Toyota doesn't see it that way

Even Jeremy Clarkson says the Prius is a not very "green" car - and that
based only on the running costs in mpg.

Oh, and for all you Topgear fans out there, the show will be back soon, the
Hamster was on the Jonathon Ross Chat Show the other evening, and seemed to
be all himself again. They have been running some "best of Topgear" bits in
preparation for the new series.

2007\01\05@101715 by Peter P.

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Russell McMahon <apptech <at> paradise.net.nz> writes:

> > 4) Rocket fuel is not anhydrous alcohol.
>
> It would esentially be if you used alcohol. Few rockets do nowadays.
> It has some advantages but it is a relatively low performance
> propellant compared to viable alternatives. eg even LOX and Kerosene*
> has substantially superior performance. (* "Jetex" and "RPx" and
> similar are special kerosenes chosen for their relative purity and
> absence of fractions which polymerise when heated and goo up your
> injectors and chamber).

Yes, that's the point. An aluminium block modern engine probably would not like
being driven to the limit with anhydrous alcohol (thermally speaking - the
thermal load would increase by more than 40% going from gas at 8:1 to alcohol
and 15:1) although Indy cars seem to do just exactly that (but then engine life
between overhauls is a few hours). I wonder what copper heads would do here (or
even silver heads for the posh - I hope that silver does not catalyze anything
bad with alcohol and nitrogen from the air - I am no chemist). Was there any
experiment with graphite or composite head engines or such ? At such high
compression (15:1) it is probably best to use direct injection only because the
heat of compression would cause serious problems for mixture compression with a
high efficiency engine (with ceramic or such insets).

> > V2 rockets used 75% ethyl alcohol + 25% water
>
> This was mainly to lower the combustion chamber temperature to suit
> the materials used. It also helped a relatively rare resource go
> further. It also didn't overly hurt net performance in this
> application but modern methods tend (not always wisely) to optimise
> performance. [[Truax et al BDB** approach compared with systems like
> eg STS/Shuttle]]

Yes, exactly. That's the point. 'Low' tech is not asked for, what is asked for
is a good match between fuel and engine to maximize efficiency and durability
with a reasonable cost and MTBF.

> > And unlike hydrogen it is not really really dangerous or hard to
> > handle.
>
> Unless you drink it (whether 85% or anhydrous).
> But, then, liquid Hydrogen is also dangerous to drink, and has no
> taste that you will ever taste if you do

Yes, I think that the powers that be are very distressed about the issue of
drinkable fuel and fuelable drink. Come to think of it, setting equally low
taxes on both would fix the problem but that would delete or merge one
government department and lower (not really, by quantity) tax revenue, so that
is more unlikely than a perpetuum mobile. New bumper sticker idea: 'Moonshine
Power!' or 'Drink *or* Drive!' (hey, this is already true ... ) On the other
hand, there are anecdotal stories about torpedo technicians drinking torpedo
fuel on the Internet ...

Money-wise alcohol is $1.23 to $1.50 / gallon wholesale in the USA (source:
Wikipedia). This is competitive with normal gas both by price and by power
(outside the US). Although alcohol has only about 70% of the heat value of
gasoline the alcohol engines (which do not yet exist in mass) have double the
compression of a gas engine and thus in theory twice the thermodynamic
efficiency. In reality this does not happen but alcohol is certainly used for
racing ... alcohol engines are no wimps for sure.

Peter P.


2007\01\05@102456 by Josh Koffman

face picon face
On 1/5/07, Alan B. Pearce <A.B.PearcespamKILLspamrl.ac.uk> wrote:
> Oh, and for all you Topgear fans out there, the show will be back soon, the
> Hamster was on the Jonathon Ross Chat Show the other evening, and seemed to
> be all himself again. They have been running some "best of Topgear" bits in
> preparation for the new series.

Last I checked it was scheduled to start on January 28th...and I'll
actually be in the UK at the time! It usually works out that I get
there just as the series ends or something like that.

Josh
--
A common mistake that people make when trying to design something
completely foolproof is to underestimate the ingenuity of complete
fools.
       -Douglas Adams

2007\01\05@122734 by Alan B. Pearce

face picon face
>New bumper sticker idea: 'Moonshine
>Power!' or 'Drink *or* Drive!'

hey, there is a country song around about a guy who only has enough cash to
buy a 6 pack or a gallon of gas, and cannot make up his mind which is most
important ... ;)

2007\01\05@131612 by Herbert Graf

flavicon
face
On Fri, 2007-01-05 at 10:24 -0500, Josh Koffman wrote:
> On 1/5/07, Alan B. Pearce <.....A.B.PearceKILLspamspam.....rl.ac.uk> wrote:
> > Oh, and for all you Topgear fans out there, the show will be back soon, the
> > Hamster was on the Jonathon Ross Chat Show the other evening, and seemed to
> > be all himself again. They have been running some "best of Topgear" bits in
> > preparation for the new series.
>
> Last I checked it was scheduled to start on January 28th...and I'll
> actually be in the UK at the time! It usually works out that I get
> there just as the series ends or something like that.

Ahh, the beauty of the internet. Top Gear is, AFAIK no longer shown at
all in Canada (it was carried on BBC World for a while, but I haven't
seen it on there for a long time, and even WHEN they carried it they
were usually quite a few episodes behind).

Similar issue with this years Dakar rally. OLN is doing the stupidest
thing possible: they are showing episodes of the rally AFTER IT
COMPLETES. This is an 17 day race, and their coverage STARTS after the
race is over. How does that make sense? I'll be watching the british
feed.

Thanks, TTYL

2007\01\05@142716 by Peter P.

picon face
Peter P. <plpeter2006 <at> yahoo.com> writes:

> 1a) Heat consumption for production vs. heat of combustion is about 3x10^7J vs
> 1.4x10^8J.

Sometimes I wonder why Murphy does not take a day off now and then. 3x10^7J is
the heat of combustion. The heat requirement for production must be (much - 30%
at least) less than this. 1.4*10^8J is wishful thinking.

Peter

2007\01\07@053218 by Peter P.

picon face
Russell McMahon <apptech <at> paradise.net.nz> writes:

> > So what's really messing up the equation is the external fossil
> > energy
> > needed to get at the biofuel.
>
> It's not that it's *fossil* energy per se that neds inputting - it's
> the fact (apparently) that overall the net process loses energy. If
> you consider biofuel to be an energy transport medium (as hydrogen is)
> and IF you have sources of energy elsewhere that are net energy
> positive but not accessible, then the biofuel may be viable (eg a
> methanol operated car may use solar energy produced in the Simpson (or
> Sahara) desert.. If though you are looking at the biofuel as being an
> energy "source" in its own rigjht there appear to be 'problems'.

I keep wondering why the powers that be insist in calculating the energy output
of biofuels with 'fossil energy input'. Obviously the production of a biofuel
would strive to use NO fossil energy. Therefore the energy input must be
calculated in biofuel energy input (as in wood, peat, solar etc).

> '> That puts forward the case for nuclear
> > (fission now, hopefully fusion in the future), hydro, wind, solar
> > etc to
> > do that.
>
> The arguments are that all of these (except for fusion) are in fact
> net energy negative and/or not renewable. eg Nuclear fission is

Look, all energy sources are net negative. 'Renewable' simply means that He3 can
be imported from offearth or that sun energy can be used in some form to
'replenish' the resources. All the bullshit statements about net 'negative' are
point-of-view euphemistical sofisms. ALL energy sources are net 'negative'
because by using them one simply taps off a little bit from the increase of
entropy that occurs anyway naturally on a billion year scale. It depends on what
one defines as 'positive', just as it depends on what one defines as 'up'.
Neither gravity nor entropy care, things will still 'fall' in the same way and
in the same direction.

The whole energy business is one of efficiency. How many % of the tapped source
turns into how many usable joules for how many $. And whether the particular
method used to tap Joules is liable to cause serious damage of some kind. It has
been calculated that the sun energy input to this planet is sufficient to supply
all energy needs a couple of times over. It is our inability to tap this source
directly or indirectly (and other sources) efficiently that causes problems.
(Or, said another way, humanity's preocupation with using energy is larger than
its preocupation with generating/finding sufficient energy for that growth -
like putting the carriage in front of the horses on a really big scale). When
and if tapped, the 'net' energy will still be negative. Similar considerations
apply to other resources, including chemical ones. Oil and fossil fuel are
'canned' solar energy after all. They are not 'renewable' because nobody can
wait 2 million years for new deposits to form naturally. From the point of view
of Earth, 2 million years is nothing. For humans, it's beyond forever. So it's
about the definition of 'renewable'. Or more exactly about the ratio between the
rate of consumption and the rate of production.

Peter P.


2007\01\07@061533 by Russell McMahon

face
flavicon
face
Major project breakthrough.
Stupid somewhat subtle fault found.
Time for a brief veg before testing to see if there are any other
findable by me now problems.

So

{Quote hidden}

We agree then :-)

{Quote hidden}

"Net negative" has the ery real meaning "net negative for me" where
"me" is the person/organisation/continent/world trying to survive. ie
IF we do this we will have more entropy and be a little colder. The
aim is to do something and have more entropy and be a little (or a
lot) warmer.

By this measure, it is said by the nay sayers that all sources of
canned energy and eiother net negative or have really nasty downsides
EXCEPT nuclear fusion. Actually, the nay sayers never mention nuclear
fusion and lunar He3 as it ruins a lovely doomsday argument :-).

> It depends on what one defines as 'positive', just as it depends on
> what one defines as 'up'.

Indeed. As above, positive is "I am warmer now". (Not just feel warm
because I've been chopping wood :-) ).

> Neither gravity nor entropy care, things will still 'fall' in the
> same way and
> in the same direction.

Black holes suck!

> The whole energy business is one of efficiency. How many % of the
> tapped source
> turns into how many usable joules for how many $.

And, as anove, the may sayers say that all sources of stored energy
take more of "my" energy to attain them than I can recover from them.
I find this vvv hard to believe, but that doesn't seem to stop them
saying it :-).


> And whether the particular
> method used to tap Joules is liable to cause serious damage of some
> kind.

Fast breeder fission tends to win better than most things, and as a
bonus produces lots of lovely shiny Plutonium..

> It has
> been calculated that the sun energy input to this planet is
> sufficient to supply
> all energy needs a couple of times over. It is our inability to tap
> this source
> directly or indirectly (and other sources) efficiently

ie at an efficncy of > 100% work done to work produced, as the nay
sayers say.

> Oil and fossil fuel are 'canned' solar energy after all.

All energy sources available to us are solar or other star sourced (or
appear to be :-) ).
Some need a bit more creative explaining to make them so. eg deep
borehole thermal which depends on the earth's core temperature is
annoying. You have to start waving fish and explaining that any
radionucleotides above iron were formed in stars. [[Iron is star
ash]].

> They are not 'renewable' because nobody can
> wait 2 million years for new deposits to form naturally.

And if they could they STILL wouldn't be renewable :-).



       Russell


2007\01\07@091225 by Peter P.

picon face
Russell McMahon <apptech <at> paradise.net.nz> writes:

> > They are not 'renewable' because nobody can
> > wait 2 million years for new deposits to form naturally.
>
> And if they could they STILL wouldn't be renewable .

Why not ? Another carboniferic (sp?) era is looming ahead with global warming
and all that. Maybe there will be dinosaurs too ?

Peter


2007\01\07@165221 by William Chops Westfield

face picon face

On Jan 7, 2007, at 2:31 AM, Peter P. wrote:

> Obviously the production of a biofuel
> would strive to use NO fossil energy.

Sure, but part of the attraction is the existing infrastructure for
alcohol production (for example.)  All of which runs on fossil fuels.
If things work out well, THEN you can look at ways of making dedicated
production lines that use alternate energy sources to produce the
alternate fuels.  But right now it "isn't economical" (sound familiar?)

BillW



2007\01\07@171850 by Russell McMahon

face
flavicon
face
>> > They are not 'renewable' because nobody can
>> > wait 2 million years for new deposits to form naturally.

>> And if they could they STILL wouldn't be renewable .

> Why not ? Another carboniferic (sp?) era is looming ahead with
> global warming
> and all that. Maybe there will be dinosaurs too ?

What I meant was the point which we both (I think) raised - energy
"sources" are really energy transfer media. It all runs downhill and
we can only choose the channels that it runs through for our
convenience. Renewed coal and petroleum products would simply be
energy inefficient but moderately convenient ways of storing energy in
an accessible form.  Just as lunar Helium 3 is.

I'm told that you can make oil and coal from raw biological materials
in extremely short time frames - months to a few years using natural
processes and garbage to oil equivalent in hours using man made
processing.

It intrigues me that there seems to be a trail of 'just achievable"
stepping stones leading off planet. This is, of course, entirely a
coincidence, or the aliens are hiding really well, or ... . Lunar ice,
lunar He3, Martian water, asteroid belt resources galore ...



       Russell


2007\01\07@172151 by Tsu Do Nimh

picon face
On 1/7/07, Peter P. <EraseMEplpeter2006spam_OUTspamTakeThisOuTyahoo.com> wrote:
> Russell McMahon <apptech <at> paradise.net.nz> writes:

> > It's not that it's *fossil* energy per se that neds inputting - it's
> > the fact (apparently) that overall the net process loses energy. If

> I keep wondering why the powers that be insist in calculating the energy
> output
> of biofuels with 'fossil energy input'. Obviously the production of a
> biofuel
> would strive to use NO fossil energy. Therefore the energy input must be
> calculated in biofuel energy input (as in wood, peat, solar etc).

I'm not a chem engineer, but a friend that /is/ tells me fossil fuels
require four times the yield of energy to recover it from the earth
and process it.

I don't understand why this argument is given against biofuels...

Tsu
--
There's no .sig like the present

2007\01\07@174641 by peter green

flavicon
face

> I'm not a chem engineer, but a friend that /is/ tells me fossil fuels
> require four times the yield of energy to recover it from the earth
> and process it.
then ask him where the hell that energy comes from.

I'm not saying that all fossil fuel recovery that happens is positive in terms of usefull energy output to usefull energy input but on average they must be otherwise fossil fuels could not be the dominant contributor to our supply of usefull energy.


2007\01\07@204544 by Peter P.

picon face
peter green <plugwash <at> p10link.net> writes:

> > I'm not a chem engineer, but a friend that /is/ tells me fossil fuels
> > require four times the yield of energy to recover it from the earth
> > and process it.
> then ask him where the hell that energy comes from.
>
> I'm not saying that all fossil fuel recovery that happens is positive in terms
of usefull energy output to
> usefull energy input but on average they must be otherwise fossil fuels could
not be the dominant
> contributor to our supply of usefull energy.

When the extraction and pumping gear on an oilfield run on power supplied by the
products of the field (which are used untaxed in situ, after slight refining and
removing things that go bang inside engines and boiler burners) the cost
(price-wise) is simply un-computable. I suppose they write it off as 'wastage'
or something like that. I have no idea what it takes energy-wise from the bottom
of a borehole to a liter of diesel in a truck's tank on another continent, but
this would be an interesting calculation to do. If anyone has a pointer, please
post it. I just doodled that lifting 1 gallon of something out of the earth from
500 meters down alone costs 15kJ before flow resistance is calculated (and at
500 meters flow resistance for a viscous fluid is enormous).

Peter


2007\01\07@205741 by Peter P.

picon face
William "Chops" Westfield <westfw <at> mac.com> writes:

> On Jan 7, 2007, at 2:31 AM, Peter P. wrote:
>
> > Obviously the production of a biofuel
> > would strive to use NO fossil energy.
>
> Sure, but part of the attraction is the existing infrastructure for
> alcohol production (for example.)  All of which runs on fossil fuels.
> If things work out well, THEN you can look at ways of making dedicated
> production lines that use alternate energy sources to produce the
> alternate fuels.  But right now it "isn't economical" (sound familiar?)

Ahh, there is a hen and there is an egg, but we don't know which is which ?
F.ex. I was thinking about a conventional power station's cooling water being
used to run vacuum alcohol distillation. Energy cost is essentially zero and the
temperature is exactly right. And there is a *LOT* of that kind of power being
tossed out. Power stations are only 40-50% efficient. I wonder if it is this
kind of 'fossil fuel' the powers that be took into calculation when they decided
that alcohol production is 'not economical' ? <g>

Peter


2007\01\07@221954 by Russell McMahon

face
flavicon
face
> Ahh, there is a hen and there is an egg, but we don't know which is
> which ?
> F.ex. I was thinking about a conventional power station's cooling
> water being
> used to run vacuum alcohol distillation. Energy cost is essentially
> zero and the
> temperature is exactly right. And there is a *LOT* of that kind of
> power being
> tossed out. Power stations are only 40-50% efficient. I wonder if it
> is this
> kind of 'fossil fuel' the powers that be took into calculation when
> they decided
> that alcohol production is 'not economical' ? <g>

Here people use waste water from a geothermal power plant to raise
shrimps.

Someone's pictures thereof

   http://yobaby.smugmug.com/keyword/jul/1/32271952

   End product

           http://yobaby.smugmug.com/photos/32271952-M.jpg


DIRECT HEAT UTILIZATION OF GEOTHERMAL RESOURCES

       http://geoheat.oit.edu/bulletin/bull17-3/art20.htm

The station (400k jpg)

       http://www.richard-seaman.com/Wallpaper/NewZealand/NorthIsland/WairakeiGeothermalPowerStation.jpg

Excellent panorama of Wairakei Geothermal Power Plant & valley
186k

       http://www.complang.tuwien.ac.at/anton/photos/nz2004/small/0115_simg.jpg


NZ tour that the above came from

       http://www.complang.tuwien.ac.at/anton/photos/nz2004/small/

2007\01\08@052716 by Tsu Do Nimh

picon face
On 1/7/07, peter green <plugwashspamspam_OUTp10link.net> wrote:
>
> > I'm not a chem engineer, but a friend that /is/ tells me fossil fuels
> > require four times the yield of energy to recover it from the earth
> > and process it.

> then ask him where the hell that energy comes from.
>
> I'm not saying that all fossil fuel recovery that happens is positive in
> terms of usefull energy output to usefull energy input but on average they
> must be otherwise fossil fuels could not be the dominant contributor to our
> supply of usefull energy.

I'm pretty sure it comes from the oil. 5 barrels -> 1 barrel.

Tsu
--
There's no .sig like the present

2007\01\08@070744 by Gerhard Fiedler

picon face
peter green wrote:

>> I'm not a chem engineer, but a friend that /is/ tells me fossil fuels
>> require four times the yield of energy to recover it from the earth and
>> process it.
>
> then ask him where the hell that energy comes from.
>
> I'm not saying that all fossil fuel recovery that happens is positive in
> terms of usefull energy output to usefull energy input but on average
> they must be otherwise fossil fuels could not be the dominant
> contributor to our supply of usefull energy.

The calculation goes like this I think:

- There's 100 TJ worth of chemical energy in the form of crude oil in a
well.
- To extract and refine it, you need 80 TJ.
- Leaves you with 20 TJ of useful chemical energy from fossil fuels.

The energy comes from the well. It costs four times the resulting useable
energy to extract and refine it. There is still a positive outcome, because
the loss in available energy stored in the well doesn't go into the
calculation. So the last (and usually skipped) calculation step is:

- After using 20 TJ of fossil energy, we (globally speaking) have 100 TJ of
fossil energy less than we had before.

All this using Tsu's numbers. I don't know if they are correct. But they
could be -- there's no general principle that says they can't be.

The reason why, despite such a claimed inefficiency, these fuels can be the
dominant contributor is that the owners sell their fossil energy stock
relatively cheaply. (Which probably will change as these stocks get near
their end. Which then probably will also change the energy supply
structure.)

Gerhard

2007\01\08@160715 by Russell McMahon

face
flavicon
face
> The calculation goes like this I think:
>
> - There's 100 TJ worth of chemical energy in the form of crude oil
> in a
> well.
> - To extract and refine it, you need 80 TJ.
> - Leaves you with 20 TJ of useful chemical energy from fossil fuels.

As the easily extracted material is expended it becomes more energy
costly to get the rest. By the time you get to the Southern Ocean and
Shale Oils it gets, they say, so energy expensive to do that you never
win. So they say. The Southern Ocean promises vast reserves but it
will be very challenging to access them.

Sooner or later Lunar Helium 3 is going to look downright attractive.
We more or less have the technology now required to access it. (ie an
order of magnitude improvement in our capabilities may be needed).
Where we once sent a few men at  a time for a few days at a time we
need to spend thousands for years. A "simple matter of engineering".

All we need now is to work out how to build something to burn it in.



       Russell

2007\01\11@115154 by Bill Clawson

picon face
In all this discussion of biofuels, I haven't heard
anyone mention that the current primary attractant to
biodiesel for the appropriate consumer is that most of
the feed stock (used fryer oil) is next to free.  As I
see it, biodiesel's attraction is that it converts
somebody else's trash/disposal problem into cheap
energy, not that it might effectively supplant our
current gasoline/diesel consumption.

.....

It would be interesting to calculate how much land
area would be required to produce half of the US's
fuel consumption in the form of biodiesel.

.....

Using vacuum distillation, could you simultaneously
brew/distill your mash to allow the yeast therein to
consume all of the mash's sugar without achieving
toxic levels of alcohol in the mash?  It would be a
shitty way to make beer, but maybe an efficient way to
brew ethanol.


2007\01\11@152252 by peter green

flavicon
face
> In all this discussion of biofuels, I haven't heard
> anyone mention that the current primary attractant to
> biodiesel for the appropriate consumer is that most of
> the feed stock (used fryer oil) is next to free.  As I
> see it, biodiesel's attraction is that it converts
> somebody else's trash/disposal problem into cheap
> energy,
quite right, but thats not what the eco-whakos would have you belive.

recycling food waste into fuel makes a lot of sense but it is important for everyone to realise that its effect on our use of other fuel sources will be pretty negligable, if biofuels are ever going to replace fossil fuels then waste-food will be nowhere near sufficiant.


2007\01\13@073428 by Russell McMahon

face
flavicon
face
> In all this discussion of biofuels, I haven't heard
> anyone mention that the current primary attractant to
> biodiesel for the appropriate consumer is that most of
> the feed stock (used fryer oil) is next to free.

That's only an extremely small part of the overall biodiesel
initiative and forms essentially no part of the commercial
justification for its use.

"The use of vegetable oils for engine fuels may seem insignificant
today but such oils may become, in the course of time, as important as
petroleum and the coal-tar products of the present time."
                                                                     
             Rudolf Diesel, 1912.

In 2003 when I travelled through Europe I noticed biodiesel (usually
95% petroleum based / 5% bio based) was available in many locations.
As noted in the article below, Renault and Peugeot have certified
truck engines for up to 30% content and suitably designed engines
should run propely on 100% biodiesel.



                   Russell


______________

From:        http://en.wikipedia.org/wiki/Biodiesel

Throughout the 1990s, plants were opened in many European countries,
including the Czech Republic, Germany and Sweden. France launched
local production of biodiesel fuel (referred to as diester) from
rapeseed oil, which is mixed into regular diesel fuel at a level of
5%, and into the diesel fuel used by some captive fleets (e.g. public
transportation) at a level of 30%. Renault, Peugeot and other
manufacturers have certified truck engines for use with up to that
level of partial biodiesel; experiments with 50% biodiesel are
underway. During the same period, nations in other parts of world also
saw local production of biodiesel starting up: by 1998 the Austrian
Biofuels Institute had identified 21 countries with commercial
biodiesel projects.



As I
{Quote hidden}

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