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Ethanol worth it?

Concerning 90/10 ethanol blend. Gasoline has a BTU value of approximately 125,000 BTU’s/gallon. Ethanol has a value of approx. 75,000 BTU’s/gallon, so a 90/10 blend produces less heat than a 100% gasoline, so fuel mileage is about 10% less. Assuming a car gets 30 mpg on gas and therefore 27 mpg on 90/10 blend, which actually emits less pollution? If this car travels 30 miles, it will burn 1 gallon of pure gasoline, but it will burn approx. 1.11 gallons of 90/10 blend. Does this second car still actually emit less pollution?

Ethanol Can Be “Worth It” For A Corn Producer!

The CO2 produced from burning ethanol is “good CO2” since it comes from growing a crop that absorbs CO2 from the atmosphere. That’s how the EPA calculates the net contribution to global warming. A vehicle that runs on 100% ethanol makes no contribution according the government. That’s not really true, since ethanol from corn requires about 70% as many BTUs from polluting CO2 to make the final product. So the gain in “good CO2” is very small. But Midwestern corn farmers love it!

Ethanol from sugarcane, as made in Brazil, is much more beneficial. It requires little fossil fuel input to create a gallon. On a recent rip to Brazil I learned that 40% of their car fuel comes from ethanol.

That’s If You Believe That “Man” Is Actually Contributing To “Global Warming” And If You Believe In The “Global Warming Theory” To Begin With.

We have been warming and cooling throughout earth’s history. The sun has the largest influence on these swings.

Many (most) scientists believe that "global warming / cooling / climate change is caused almost entirely by sun activity.

I can find more good things that would come from global warming than bad things. I am not at all in favor of even trying to cool the Earth, even if that was possible.
I just came down off the roof from shoveling 22 inches of fall snow (not to be confused with snowfall). This is Autumn. Temperatures have been well below normal and more in the forecast. Here’s where people will try and tell me that this is because of “global warming theory”. This country cannot survive or afford chasing this theory.

If the country is to survive ECONOMICALLY, it has to do some of the following:

  1. REDUCE oil imports; and accomplish this by replacing it with more domestic sources of fuel. Ethanol from cellulose (waste plant materials) is a good source.

  2. Reduce engine size and increase fuel mileage of motor vehicles

  3. Increase the use of public transportation

  4. Accelerate the development of electric cars for specific urban applications.

Any country on earth that is a major oil importer has a whole arsenal of these measures in place to curb oil use and stay solvent. Japan and Germany have no oil, but the are major net exporters of industrial goods and limit the use of oil as much as possible.

The US behaves, thanks to George Bush) like it was still a major net experter of industrial goods and self-sufficient in oil.

So, if you don’t believe a word about global warming and think Al Gore should be locked up, you still need to believe in cutting oil use and keeping the US financially sovent.

Three problems with the scenerio:
(1) production of ethanol uses petroleum resources
(2) it takes more ethanol to get the same energy
(3) producing enough ethanol to have any real impact would require that the agricultural community expand capacity greatly. To their credit, they’ve developed markets for virtually all of their products and byproducts.

I’ve read calculations that producing ethanol in sufficient quantities to have an impact would actually use more petroleum resources than it would save if one calculates the increased amount of fuel needed due to the lower energy.

Personally, I think there’s more politics involved than actual good sense. To me it’s akin to promoting flourescent lightbulbs because they’re more energy efficient when they contain mercury vapor. Or mandating low-water-use toilets that have to be flushed repeatedly to do the same job that one flush of an old fashioned toilet does. Or mandating MTBE…now THAT was a winner!

The US ethanol industry is mostly politics and very little responsible energy accounting. The recent runup in corn prices caused a panic in Mexico since corn used for tortillas doubled in price overnight. But those Iowa farmers loved George Bush! Most of us have concluded that using food to make fuel for thirsty motor vehicles is immoral as well!

The second generation ethanol plants now under development will us agricultural waste or algea to ferment into ethanol. Such programs make more sense.

" That’s If You Believe That “Man” Is Actually Contributing To “Global Warming” And If You Believe In The “Global Warming Theory” To Begin With.

We have been warming and cooling throughout earth’s history. The sun has the largest influence on these swings.

Many (most) scientists believe that "global warming / cooling / climate change is caused almost entirely by sun activity.

I can find more good things that would come from global warming than bad things. I am not at all in favor of even trying to cool the Earth, even if that was possible.
I just came down off the roof from shoveling 22 inches of fall snow (not to be confused with snowfall). This is Autumn. Temperatures have been well below normal and more in the forecast. Here’s where people will try and tell me that this is because of “global warming theory”. This country cannot survive or afford chasing this theory."

But you can’t say that! This is a car forum! You said that yourself…

Enough needling (for now).

You can’t judge climate change by assessing the weather. Global warming is a change in climate, which is measured over long periods and includes natural fluctuations about average conditions. Weather is the fluctuation about the average. And I don’t think any reasonable scientist would argue that this current warming trend is much smaller than many catastrophic changes in the past. But it did start during what should be a cooling period, and the average temperature is going up at an alarming rate. Significant changes in seawater temperature and frozen land temperature could cause the release of methane, and that would be much worse for global temperatures than carbon dioxide. WE have a ways to go before we get there; I’ve seen estimates of at least 30 years. But it does take a considerable time to change our corner of the world, let alone the rest of it.

I asked about the emission numbers, not the politics involved. Even though I agree with some of the replies, I was really only interested in the actual emission numbers form the vehicle, not the other polluting factors (ethanol production, fertilizer, etc) involved.

In theory, with a 90/10 percent blend there would be a 10% drop in mileage…
but in reality, its more than 20% drop in mileage.

A car gets 30 mpg with gas and 27 mpg with ethanol… the tank is 20 gallons.
The tank with gasoline will go 60 miles further.
divide 60 MILES by 30 MPG and you get a savings of 2 gallons.
multiply the 2 gallons by todays price and you’ll save $4.30 per tank.
MOst cars get a difference of 4 MPG between gasoline and gasohol, which changes the savings to $6.45 per tank.
So to answer the question. NO ETHANOL IS NOT WORTH IT.
Hope this helps,
Caballero

If you are only concerned with tailpipe CO2 emissions, NO, ethanol is not worth it. It has lower heat content, gets fewer miles per gallon, and your dollar savings on fuel are about zero. And I’m sure you are not interested in Iowa farm votes!

However, ethanol reduces the tailpipe oxides of nitrogen (NOX)by 15% in the exhaust compared to straight gasoline. So, in Los Angeles and Denver, and other smog-prone areas it helps keep the air cleaner.

Ethanol is not worth it. It is not a viable alternative to petroleum. This is especially true because it takes an enormous amount of petroleum to mass produce and distribute ethanol. Ethanol is a waste of time and money.

“Does this second car still actually emit less pollution?”

It depends on how many BTU’s/lb of carbon are in ethanol vs gasoline.

You could eliminate the carbon and run your internal combustion engine on hydrogen.

Ethanol is ~35% oxygen by weight and that O has no fuel value since we already have an abundance of O in the intake air. That’s the main reason why there’s less BTU’s/gallon.

Pure iso-octane, C8H18, is 81% carbon by weight.

Ethanol, ignoring the O, is 80% carbon.

I say it’s a wash IF THE FUEL IS BURNED COMPLETELY.

After taking my MB 560 SL to my mechanic for a tune-up because it was hesitating and getting poor gas mileage. (I have to use high test gas.) He told me it was the ethanol in the gas and before an expensive tune-up to try a gas treatment. After a short time the hesitation was gone. I have to put the treatment in with all the gas I use except Shell which is my local station. Not only do I have to pay outrageous premium prices but I get worse mileage and have to use an additive. Being a farmer wife at one time I can think of much better uses for corn!!!

Not this again! Even George W. Bush admitted global warming was real before he left office. Some Republicans are even saying it is too late to do anything about global warming. How convenient!

Do you still think the sun orbits a flat earth? Columbus and Galileo had their detractors too, and you sound just like them.

Although Ethanol has not become the answer we hoped for, it still has potential. Manufacturing processes that use less energy are still being developed. Biodiesel looks like a better avenue, but Ethanol still has a chance if the processes for making it can be improved. If I didn’t have a bad back, I would be tempted to start an energy farm, where biofuels can be made using wind and solar power. I would choose a crop that doesn’t need to be watered and can be easily converted to either ethanol or biodiesel. There will always be visionaries and the naysayers that try to hold them back. I will always hope for the visionaries and their ability to ignore the people who say “it can’t be done” even when it can. I guess that makes me an optimist.

Perhaps you should get a second opinion. I don’t think the Ethanol was really the problem. It is more likely it is a defective knock sensor, EGR valve, or something else he overlooked.

Pacific Ethanol just declared bankruptcy today…The whole industry is in a tail-spin. They are trying to get the EPA to increase the amount added to gasoline to 15%…

What they need to do is establish a distribution network of their own and stop trying to get the oil companies to give them shelf-space. Then sell 100% ethanol into cars that are designed to burn it. Ethanol is very high octane. Purpose-built engines could utilize 14 to 1 compression ratios and get decent mileage. Burning it in an engine with a 9 to 1 compression ratio is a waste…

Last year I asked what was special about the ethanol that comes from processing sugar cane. The responses were that nothing is special about it, ethanol is ethanol. What is special about GETTING your ethanol from sugar cane is that it returns more ethanol for the same amount of processing as compared to corn.

MUCH, MUCH more! It essentially grows by itself in a tropical climate, does no need irrigation and usually no fertilizer. The fermentation takes place of the WHOLE stalk, not just the seed, as in corn ethanol.

The leftovers can be burned as fuel for the process in special boilers.

In other words, ethanol from sugar cane uses the whole plant and uses it very efficiently.

If a good deal of petroleum is used to make ethanol, then it is a shell (Shell) game rather than an improved energy source. How much petroleum is used to produce ethanol, when petroleum is used to power farm machinery, and to produce fertilizer and other agri-chemicals? Energy from ethanol combustion is somewhat cleaner, even though the volume of ethanol for the same amount of power is greater as compared to petroleum. Is more of not so dirty, cleaner than less of dirty? I understand that a %100 ethanol powered vehicle produces significantly less pollution than petroleum powered, even though the volume of fuel used for the same energy would be about 40% more.