Ethanol vs. Methanol
Peter R. Carpenter
Whenever people talk about alternative fuel mixtures, someone always
points out the damage that methanol can cause to aluminum carbuerators(?sp).
Is this a red herring? Why use methanol, which must be produced from
coal or methane gas, when ethanol is simple grain alcohol? Archer Daniels
Midland Corp., who advertises on the "Sunday morning politics" circuit
"ADM - super market to the world" indicates that they use a lot of corn
to make ethanol, for mixing with gasoline.
So why does methanol keep getting mentioned? Are these folks just being
obstructionist? Is methanol a much higher energy fuel?
Is it true that in Brazil they use 100% ethanol, with no gasoline, and
no modifications necessary?
Comments?
---
Pete Carpenter
P.O.Box 360935
Milpitas, CA 95036-0935
{amdahl,ames,pyramid,uunet}!oliveb!tymix!cirrusl!pete
-----------------------------------------------------
Mike Smith
>Can someone explain the difference in energy between these two alcohols?
Methanol is H3C0H
Ethanol is H3CH2COH
The extra H2C in the middle is the difference. Methanol has less energy
per volume than ethanol. It is more corrosive (though I have yet to
see any evidence of corrosion in my lawn mower after several YEARS of
running methanol in it ... Briggs and Stratton must do something right!)
Methanol is also easy to make from coal at low prices. Ethanol is
harder to make from coal and, thus, more expensive. Ethanol made from
corn is more expensive since corn is more expensive than coal. It also
removes corn from the food baskets of people, cows, chickens, and pigs.
In cold weather it is harder to start an engine on methanol than on ethanol.
So, what will you do? The 'better' fuel is more expensive and has
political implications vis a vis food aid to starving nations.
It may also be the case that any really large consumption of ethanol
would exceed the ability to grow starting material!
The cheaper fuel is harder to make work due to vaporization temperature
and corrosion issues. It is also politically loaded in that many
folks don't like the idea of digging up the {west, midwest, Virginia,
etc.} to get the coal and don't like the big companies that own the
coal.
>Whenever people talk about alternative fuel mixtures, someone always
>points out the damage that methanol can cause to aluminum carbuerators(?sp).
>Is this a red herring?
I think it is, since I've seen no evidence of such corrosion in my own
experience and since plastic is cheap. You DON'T need a stainless
steel fuel tank. You MAY need a plastic lined steel one. Methanol
is commonly used on Sail Boats as a stove fuel and is widely available
in plastic bottles. To me corrosion looks like a red herring. It's
a solved problem at worst case. (Go look at alcohol stoves on boats!).
>Why use methanol, which must be produced from
>coal or methane gas, when ethanol is simple grain alcohol? Archer Daniels
>Midland Corp., who advertises on the "Sunday morning politics" circuit
>"ADM - super market to the world" indicates that they use a lot of corn
>to make ethanol, for mixing with gasoline.
Cost and volume available. See above.
>So why does methanol keep getting mentioned? Are these folks just being
>obstructionist? Is methanol a much higher energy fuel?
Lots of it can be made cheaply from coal with present technology.
>Is it true that in Brazil they use 100% ethanol, with no gasoline, and
>no modifications necessary?
Yes. They also have cars that were built with ethanol in mind. No need
to modify since it was designed in from the start. They also don't have
to try starting their alcohol fueled engines in North Dakota or upper
Michigan, or Idaho in winter at 40 below zero (when even gasoline is
thinking about turning to jelly like the oil already has ...).
The tropics provide a nice built in fuel warmer ...
>Comments?
Methanol has some problems as a fuel. They are relatively minor and
can be solved by a freshman engineering class at a good University.
(Or, more quickly, by the grease monkey at the local race track.)
There are literally dozens of methanol fueled demonstration cars
driving all over the place today and thousands of methanol fuelers
running at local race tracks across the nation. (Not to mention the
millions of model airplane engines that run on methanol with a little
nitro methane added).
Moonshine runners have been known to fuel up a car with 'moonshine'
as a way to transport it where it was hard to find. Mostly it takes
opening up the fuel jets some. In really cold weather, a squirt
can of 'cold weather starting fluid' (often ether) is helpful. A
squirt of plain gas is usually enough unless your talking serious cold.
If you design an engine to run ONLY on alcohol you can push the
compression up Real High for performance that a gasoline engine can
only dream about (which is why it is the fuel of choice for all those
big drag race cars, and other 'fuelers'). They worry about the water
that pure alcohol sucks from the air, since any dilution will cut
their performance. Mere mortals need not worry and just need to open
up the fuel jets a little wider (we have no Rules Committee deciding
how much fuel we can carry and how often we can fuel up...).
--
E. Michael Smith e...@apple.COM
'Whatever you can do, or dream you can, begin it. Boldness has
genius, power and magic in it.' - Goethe
I am not responsible nor is anyone else. Everything is disclaimed.
John G. De Armond
>Whenever people talk about alternative fuel mixtures, someone always
>points out the damage that methanol can cause to aluminum carbuerators(?sp).
>Is this a red herring?
This is getting to be a Frequently Asked Question. No, it is not a
red herring. Methanol will rapidly and completely turn light metals
into white powder. I learned that lesson the hard way when using
methanol as a racing fuel. If you want to see for yourself, go to
the hardware store, buy a gallon, and chunk some aluminum foil into it.
>Why use methanol, which must be produced from
>coal or methane gas, when ethanol is simple grain alcohol? Archer Daniels
>Midland Corp., who advertises on the "Sunday morning politics" circuit
>"ADM - super market to the world" indicates that they use a lot of corn
>to make ethanol, for mixing with gasoline.
The traditional reason for mentioning methanol in the same breath as
motor fuels is that a) it is cheap to make relative to ethanol, b)
it is widely used as a racing fuel and thus well known as a motor
fuel, and c) you don't have to worry about the Prohibitionists jumping
down your throat screaming BOOZE with methanol.
Ethanol carries a bit less oxygen in its structure and thus will run
a bit leaner than methanol. A good rule of thumb is that methanol
consumption is just about twice that of gasoline in a given engine
and ethanol will be a few percentage points behind it.
Both alcohols have several disadvantages that will make it impractical as
a motor fuel for most average appliance-operating drivers. First,
its high heat of vaporization and low vapor pressure means that unassisted
cold starting below about 40 degrees is impossible and lots of carb
heat is necessary at all times to prevent carb icing. I've seen
racing carbs ice even in the summertime. Aux starting fuel, such as
gasoline or propane would be almost mandatory for low temperature
starting. Even if sufficient spark and carb heat were somehow to become
available, the huge flow of fuel into cold combustion chambers would
cause severe abrasion as the alcohol washes the oil from the cylinders
and dilutes the crankcase oil.
Next, alcohol mixes poorly with oil, especially if the alcohol is hydrated
(an almost inevitable condition). This means that the oil will rapidly
sludge and become corrosive. Race mechanics address this situation by
changing the oil after each race. Consumers are not likely to
adhere to such a dicipline. Synthetic oils may hold some promise but
I've read nothing definitive on this subject.
Finally, since about twice the volume of alcohol is needed as for
gasoline, mileage will be about half that of gasoline. Assuming
that per-gallon costs are about the same for the two, (a reasonable
assumption since the greenies will encourage taxes to eat up any
differences) people will be VERY unhappy with large cars that get under
10 mpg and small cars that get under 20. Not to mention that either
shorter range will have to be accepted or larger tanks fitted
which will hurt mileage even more.
I don't personally think that alcohol will become anything more than
an additive to more normal fuels. Alternative fuels will most
likely be some kind of synthesized gasoline-like liquid that burns
with similiar characteristics to gasoline.
>Is it true that in Brazil they use 100% ethanol, with no gasoline, and
>no modifications necessary?
No, not at all. They have converted over to 100% ethanol fuel but their
cars are purpose-built for the fuel. Brazil's experience in this form
of social engineering will likely be used for years to come as justification
not to repeat the mistake. The original conversion was motivated by a
combination of nationalist pride, a huge national debt, essential no petroleum
reserves and a huge surplus of sugar cane. Motorists pretty much have
to put up with the driveability problems. Cold start problems are, of
course, not a problem since Brazil is in the tropics.
What they found was that in order to produce enough ethanol to supply the
(relatively poor) country with fuel, all the surplus sugar cane
crops had to be consumed. Worse, demand encroached into that
sugar that normally was sold in foriegn trade, thereby denying them
of valuable dollars. An article I recently read quoted their energy
minister as saying that they regret making this experimental mistake
and that they would most likely reconvert to petroleum fuels.
A very valuable lesson.
John
--
John De Armond, WD4OQC | We can no more blame our loss of freedom on congress
Radiation Systems, Inc. | than we can prostitution on pimps. Both simply
Atlanta, Ga | provide broker services for their customers.
{emory,uunet}!rsiatl!jgd| - Dr. W Williams | **I am the NRA**
Peter R. Carpenter
>
>Methanol has less energy
>per volume than ethanol. It is more corrosive (though I have yet to
>see any evidence of corrosion in my lawn mower after several YEARS of
>running methanol in it ... Briggs and Stratton must do something right!)
>
>Methanol is also easy to make from coal at low prices. Ethanol is
>harder to make from coal and, thus, more expensive. Ethanol made from
>corn is more expensive since corn is more expensive than coal. It also
>removes corn from the food baskets of people, cows, chickens, and pigs.
Thanks for the info. Without getting too terribly political, aren't we
paying farmers NOT to grow corn? I think this is a good case for removing
farm subsidies. Then the better fuel will be less expensive to make, the
added volume of business should make the farmers happy, and the taxpayers
won't have to pay for subsidies and get cheaper gas-ahol to boot!
SOAP BOX MODE - OFF.
James W. Swonger
>ethanol. You need not use feed grain, you can use wood scraps or
>other 'trash' biomass to make ethanol.
>--
>
Can you tell me where I can find out more about this? I've only seen
wood>methanol digesters up to now. Is this process practical on a small
scale?
Mike Smith
>>Methanol is also easy to make from coal at low prices. Ethanol is
>>harder to make from coal and, thus, more expensive. Ethanol made from
>>corn is more expensive since corn is more expensive than coal. It also
>>removes corn from the food baskets of people, cows, chickens, and pigs.
>Thanks for the info. Without getting too terribly political, aren't we
>paying farmers NOT to grow corn? I think this is a good case for removing
>farm subsidies. Then the better fuel will be less expensive to make, the
>added volume of business should make the farmers happy, and the taxpayers
>won't have to pay for subsidies and get cheaper gas-ahol to boot!
This question leads to a long discussion of price supports for agriculture.
A VERY SIMPLIFIED version (as relates to corn and ethanol):
Farm income is dependent on a highly volitile set of factors. Most farm
subsidies are aimed at stabilizing prices (rather than just jacking them
up) at a level where farmers can make a small profit. Farmers don't make
much money, even with price supports (your talking about 10ish percent
in a very good year.) That 10%, if totally applied to the cost of corn,
wouldn't make a significant difference to the price of ethanol, since
corn is only part of the cost of making and delivering ethanol. The
quantity of land kept out of production is also rather small.
Would removing the price subsidies make for cheaper corn? Sometimes yes,
sometimes no. Volatility would go up. In bumper crop years the price
could fall below the cost to produce (and, historically, has in times
of no price stabilization) and many farms either go under or stop growing
corn. Yes, you read right. When the weather is good, much more crop
is produced. The extra supply drives the prices down rather sharply.
A 'bumper crop' year is usually not a 'good year' in agriculture
commodities.
In low crop years the price would climb dramatically, as would
beef, chicken, fish (farmed catfish and trout), pork, etc. prices.
Including motor fuel alcohol. The 'added volume' of business wouldn't
have much effect on the weather or corn blight; so volatility would remain.
Most farmers would rather have less volatility than the extra volume at
lower prices ...
Strangely enough, since motor fuel consumption is rather insensitive
to price changes (price in-elastic), most of the change in corn available
would have to taken up by things that are price sensitive; which just
happens to be beef, chicken, fish, pork, etc. ... The cars would be
fed, people would eat less meat. You might consider this a good thing,
you might also not like it.
The silver lining: There is a process to convert woody material to
ethanol. You need not use feed grain, you can use wood scraps or
other 'trash' biomass to make ethanol.
Mike Smith
>>>In article <79...@goofy.Apple.COM> e...@Apple.COM (Mike Smith) writes:
>>The silver lining: There is a process to convert woody material to
>>ethanol. You need not use feed grain, you can use wood scraps or
>>other 'trash' biomass to make ethanol.
> Can you tell me where I can find out more about this? I've only seen
>wood>methanol digesters up to now. Is this process practical on a small
>scale?
The reference is a paperback book titled something like 'The Solar Alcohol
Fuel Revolution' or some such ( Warm Fuzzy, to borrow Johns term, book
if ever there was one). I'll get the correct title and post it in a day
or two. It refers to a U.S Army {mumble} project that developed an
enzyme to break down cellulose to sugar. I'll get the bibliography
entry for it too ...
It isn't particularly suited to small scale, unless you buy the enzyme
from someone else.
Russ Cage
Figures I have seen quoted for energy content:
Gasoline 116,000 BTU/gal
Methanol 69,000 BTU/gal
I have seen the number "75%" quoted for the energy of ethanol vs. gasoline.
>Whenever people talk about alternative fuel mixtures, someone always
>points out the damage that methanol can cause to aluminum carbuerators(?sp).
Methanol is corrosive to aluminum. The auto companies are talking about
using some rather exotic materials, like fluorinated plastics, to handle
the witches-brew fuels of the future. They are a definite storage hassle.
>Is this a red herring? Why use methanol, which must be produced from
>coal or methane gas, when ethanol is simple grain alcohol?
The amount of energy put into a gallon of ethanol made from corn,
in the form of fertilizer, pesticides, and diesel fuel for the
farm equipment, comes out to more than the energy of the ethanol.
Sure, ethanol is great... if you grow corn for a living. The tax
subsidy of gasohol winds up paying ethanol producers about $2.00
per gallon of a fuel with only about $.75 worth of energy in it.
Methanol can be made from coal or natural gas. Unlike the gasoline
or diesel which must be imported to make corn, we have these locally.
>Is it true that in Brazil they use 100% ethanol, with no gasoline, and
>no modifications necessary?
Modifications are definitely necessary. Among other things, the
fuel system must handle the larger volume of ethanol required.
This means re-jetting carburetors or re-calibrating fuel injection
systems to deliver the increased amount of fuel.
Cold starting is also nearly impossible; the vapor pressure of
alcohol is very low. If you don't live in a warm climate, another
fuel will be required to start the engine. (Butane, which is
already added to gasoline for that purpose, seems ideal. It
could be stored separately under pressure to eliminate evaporation.)
--
Oversimplification doesn't solve problems, it just
(313) 662-4147 changes them into less tractable problems.
Russ Cage, Robust Software Inc. ru...@m-net.ann-arbor.mi.us
Mike Smith
>In article <15...@cirrusl.UUCP> pete@cirrusl (Pete Carpenter) writes:
>>Can someone explain the difference in energy between these two alcohols?
>Figures I have seen quoted for energy content:
>Gasoline 116,000 BTU/gal
>Methanol 69,000 BTU/gal
and
Ethanol 95,000 BTU/gal
Kerosene 135,000 BTU/gal
Fuel Oil 148,000 BTU/gal
Propane 92,000 BTU/gal
Butane 102,000 BTU/gal
(Gas can range from about a little less than 116k BTU/gal to 128K BTU/gal.)
>I have seen the number "75%" quoted for the energy of ethanol vs. gasoline.
This ignores the added efficiency with which alcohol can be burned
in an engine. You can use much higher compression in an alcohol
engine, which tends to put ethanol at about the same energy delivered
to the wheels per gallon.
The following quotes come from 'Solar Alcohol the Fuel Revolution'
sited in another posting:
Pg. 81:
SCIENCE magazine reported in 1979, (Vol. 195) that ethanol is
"superior" to gasoline as a motor fuel, delivering liter for liter as
much power with much less pollution in a properly tuned engine.
[...]
Henry Ford's first engine burned alcohol. His first Model T
was designed to burn kerosene, alcohol, or gas, as it was not clear
in the early 1900's which fuel would be the most economical and/or
available in different parts of the country and in the world.
>>Whenever people talk about alternative fuel mixtures, someone always
>>points out the damage that methanol can cause to aluminum carbuerators(?sp).
>Methanol is corrosive to aluminum. The auto companies are talking about
>using some rather exotic materials, like fluorinated plastics, to handle
>the witches-brew fuels of the future. They are a definite storage hassle.
I've just stored it in the cheap plastic bottle it comes in from the
store. Go to a Ships Chandlery (boat store for sail boats and such)
and look at the alcohol fuel jugs and alcohol fuel stoves. Doesn't
take NEW or EXOTIC technology. Wood alcohol has been in use for
hundreds of years. There is more to the world than aluminum (my
aluminum presure cooker was eaten by some acid tomato sauce; my
stainless steel presure cooker wasn't all that much more expensive...).
>>Is this a red herring? Why use methanol, which must be produced from
>>coal or methane gas, when ethanol is simple grain alcohol?
>The amount of energy put into a gallon of ethanol made from corn,
>in the form of fertilizer, pesticides, and diesel fuel for the
>farm equipment, comes out to more than the energy of the ethanol.
Can you site a source for this statement? I've seen nothing to
support this position in print. It doesn't agree with my
intuition about farming, but I'd like to see some facts ...
>Methanol can be made from coal or natural gas. Unlike the gasoline
>or diesel which must be imported to make corn, we have these locally.
Diesel engines can be run, and rather easily, on ethanol. I've
personally used about 50%-75% alcohol in a Volvo Penta Marine Diesel
engine (10hp, 2 cylinder) by just dribbling it into the air intake.
(diesel fuel was the other 25%-50% in the usual way).
Many tractors run on gasoline and could be converted to alcohol.
>>Is it true that in Brazil they use 100% ethanol, with no gasoline, and
>>no modifications necessary?
>Modifications are definitely necessary. Among other things, the
Semantic quibble: Modifications are NOT done. The cars are built
to be alcohol burners from the very start. They are built new to
use alcohol and already include the differences of design that make
alcohol easier to use.
>Cold starting is also nearly impossible; the vapor pressure of
>alcohol is very low. If you don't live in a warm climate, another
>fuel will be required to start the engine. (Butane, which is
>already added to gasoline for that purpose, seems ideal. It
>could be stored separately under pressure to eliminate evaporation.)
It's easier than that. Again from "Solar Alcohol":
Also reported was a successful, low-cost ethanol-conversion
on a 1964 Rambler Classic. Scott Skylar, Washington Director of the
National Center for Appropriate Technology, is now driving around a
190 proof ethanol automobile. He finds that it gives milage as
good as gasoline, but doesn't start on chilly days at 60% or less
of battery efficiency.
He solves this problem with a Ford electric window-washer
pump with a plastic fluid reservoir. The squirter nozzle feeds a
small amount of gasoline directly into the carberator. He just
pushes a button, starts the car, and lets it run on ethanol.
[end quoted material]
I don't know if I'd want to use butane. It would be much easier
to have a second 'windshield washer' installed under the hood.
Pushing a button before starting isn't a big deal. I do it on
my diesel truck every time its cold out.
For those interested in running alcohol, you can buy all the parts
you need TODAY OFF THE SHELF. It won't be cheap, since the parts
are sold for car racing to folks who pay lots of money for performance
regardless of $$$ ... For example, it can run up to $1000 for a
high performance carb for a chevy small block.
But if you really want to tinker, go to your local speed shop.
(Mine is Davis Motors 489 South Market Street, San Jose, Ca. 95113)
and ask the local wizzard what it would take to convert. Figure a
carb, new rings and pistons (higher compression), and maybe replacing
the rubber in your fuel system with silicon rubber parts. Plan on $1500
or so for the parts (these are Performace Racing parts!) and have
fun. Alcohol has no unsolved problems, just cost issues.
At Davis, fuel cost varies with quantity. It cost $2.41/gal for
methanol in five gallon jugs; If you buy in bulk it can drop to
$1.20 per gallon in 550 gallon purchases (10x 55 gallon drums).