Friday, September 21, 2007

More on why ethanol is bad

Well I was surprised this morning when I opened up the paper today. Yes I am one of those people who actually reads the paper still. It does have an added benefit that I can keep my bird's cage clean. Low an behold there was a nice article about the evils of ethanol and how it will lead to food shortages. This article came out the St. Paul Pioneer Press, and can be found here.

This goes out to the person who was first to post to my site and I congratulate them for having the courage to do so, but I have a feeling that they were trying to convince me that I was wrong. Well since there are some people who doubt me on the problems with ethanol it is time to be torn a new one. I am going to go point by point through the points that are incorrect on the site mentioned in their post and bury them with the facts and truth. The site that is mentioned in their comment is Clean Air Choice. Also on the Clean air choice site they claim that ethanol will not affect food prices, guess what this site is wrong, and the individual who commented was wrong. See these 2 articles from CNN: (article 1) (article 2) and this one from today's Pioneer Press. Guess what you are wrong corn fuel will raise the cost of food.

So lets tear into the benefits that Clean Air Choice claims from ethanol. You can pull the page up here that makes the benefit claims.

Claim #1 Reduced demand for middle east oil:

This claim is of minor consequence. Here is the big secrete most of our oil does not come from the middle east. The most recent month that the the department of energy has data on is June of 07. We imported 405,019 barrels of oil of that 71,171 came from the Persian gulf. That is 17.6% of all of our imported oil. Our internal production was 154,183 for the same month so the total percentage of oil we got from the middle east in June was 12.7%. I hate to break it to you but 12.7% is not much and could be met by other sources. Yet a decrease is a decrease so this one I will toss to the other side.

Claim #2 Ethanol is renewable:

Yes it is. But remember that the growing of commercial crops does require fertilizers and a lot of water and the environmentalists don't like use using either.

Claim #3 Ethanol is safe and fully approved:

I can only assume that by “fully approved” is in reference to the fact that it can be run in Flex Fuel Vehicles (FFVs), this means nothing really since most vehicles are not FFVs. I can only assume that they mean that ethanol is safe for engines. This is true to a point, remember my previous ethanol post, in approved vehicles like FFVs there is not a problem, but in non approved ones this is a very bad idea. One tankful won't do any permanent damage, but will make it run poorly. Here are some problems with using ethanol, yes even 10% blends, in non approved cars.

  • It absorbs water (will even do this in FFVs)
  • any absorbed water can freeze in fuel lines in the winter
  • erodes some plastics (These are usually the ones in the fuel pumps) this is know to be a cause of fuel pump failure even with 10% blends
  • erodes aluminum
  • erodes some natural rubbers
  • is more corrosive than water to steel

Now the erosive and corrosion problems are solved in FFVs but these problems in non FFVs occur outside of the warranty period and usually start showing up after 150,000 miles. I wouldn't call this safe.

Claim #4 E85 is cleaner:

Also as mentioned in my previous ethanol post not it is not. They say it results in less CO2 which is true, but 30%, for a lot of people that could be done by getting their cars tuned up, properly inflating their tires, and better driving habits. As far as producing less real EPA pollution I question this. It will produce less unburned hydrocarbons because there are fewer hydrocarbons in ethanol. Also it will produce fewer sulfur compounds since it contains fewer. It will however produce more NOx in a properly functioning engine since these are a product of high compression combustion. Ethanol works best in high compression engines, usually much higher than regular cars. A standard car usually has a compression ration of 8:1 where as ethanol works well around 12:1 up to 14:1 so 50-75% more compression. I hate to break it to you that unless you are running at these high compression ratios you will not burn all the ethanol, and even at 8:1 it would produce the same amount. Also higher compression allows you to burn more of the fuel so standard compression engines will blow unburned ethanol out the exhaust. Also as far as producing fewer smog producing pollutants this has been proven wrong here is an article from the New Scientist that proves otherwise. There is another issue too the evaporative loss issue. Ethanol is much more likely to evaporate out of your tank thus making the problems discussed in the New Scientist article worse, not to mention all that unburned fuel leaving the exhaust pipe of you low compression FFV.

Claim #5 E85 is less toxic:

See response to claim 4. Also I believe that the combustion temperatures inside an engine (about 2300 kelvin or about 3600 Fahrenheit) would breakdown these compounds into things like other hydrocarbons or just burn them up. I am not a chemist but I know there is a temperature at which things break down and become harmless or oxidize and become harmless and it is near the mentioned values.

Claim #6 E85 outperforms gasoline:

Yes it has over 100 octane (actually around 105 to 110), big deal most people don't know what octane means, and I can buy 110 octane gasoline that is unleaded. So now what does this number mean, I can get all technical but simply put, the higher this number the more you can compress the fuel without having problems. By using higher compression in the engine an engine can become more efficient, more compression higher temperatures, higher temperatures more efficient But let's look at their claim they say it burns cooler than gasoline in the same engine so it can't be more efficient. Now onto the more horse power, what does this value mean. Horse power is simply a measure of how much energy is released at a given time. Now we are going to wander off into math land to prove that this is really difficult to achieve. The combustion of ethanol happens at around 1920k (kelvin the scientific measure of temp) where as the combustion temp of gas happens around 2030k. So now we will look at the maximum efficiency that can be achieved we can use Carnot efficiency since it sets the upper bound. So we make an assumption of the ambient temperature of 294k (70 Fahrenheit) and use our equation

  • ethanol
    • 1-(294/1920)=.846
    • or maximum theoretical efficiency of 84.6%
  • Gasoline
    • 1-(294/2030)=.855
    • or maximum theoretical efficiency of 85.5%

So here we can see burning ethanol is not as efficient as gasoline. Now this is the theoretical maximum efficiency the most efficient piston engine gets in the low 40%. But keep in mind that the reduction would be the same for both engines so let's say a gasoline engine is capable of 35% (this is average) efficiency then an ethanol one would be able to get 34.5% or so.

Also ethanol seems to have a much lower energy than gasoline by volume which is how your car delivers fuel. A gallon of ethanol only has about 67% the energy content of a gallon of gasoline.

Now we need to look at what this means for power, power as mentioned before is just a measure energy released in a given amount time. The time frame to look at is 1 combustion cycle, this will be the same for gasoline as it is for ethanol (there are slight differences, but by keeping them the same it doesn't make ethanol look as bad, gasoline burns faster and produces power faster) so if we burn the same amount of fuel in the same time we can do these calculations. We will need to go off to math land again. To make number easy to work with let's say that the volume of gasoline burned in a combustion cycle has 1000 units of energy

  • ethanol
    • the same volume of ethanol has 670 units of energy
    • now we multiply that by the efficiency (670*.345) and get 231 usable units of energy per combustion cycle
  • Gasoline
    • 1000 units of energy for the same volume of fuel as ethanol
    • now we multiply that by the efficiency (1000*.35) and get 350 usable units of energy per combustion cycle

What does this mean, well it means that we get less usable energy out of the engine on ethanol than gasoline. This means that our horse power is lower while consuming the same amount of fuel. Less power also means less work done work in a car is distance traveled. Now it is possible to burn twice as much ethanol than gasoline so lets see what we get for power.

  • Burning twice the volume of ethanol as gasoline
    • we now burn a volume of fuel with 1340 units of energy per combustion cycle
  • multiply that by efficiency (1340*.345) and we get 462 units of usable energy per combustion cycle

Now this may be what they were talking about when they said more power but we did this by burning twice as much ethanol that gasoline so we get half the miles per gallon. But we get a 21% increase in total power output. Unless you are racing this is a bad deal and you will see why in claim 7.

The next part of this is they claim that it keeps you engine clean. This it does do because it is an industrial solvent. It also does not varnish like gasoline. So yes this is true, but if you use the fuel injector cleaners from time to time this isn't a problem.

Claim #7 it is cheaper per gallon:

Yes it is cheaper per gallon but vastly more expensive per mile. So now let's examine this with some math and facts. Here we won't take into account that efficiency thing which will make ethanol look even better. Let's say you get 10 miles to the gallon on gasoline while efficiently burning it. Then let's say you can also just as efficiently burn ethanol how much would you spend to drive the same distance. Well we need to make some assumptions, the first is the cost of fuel, lets assume a price difference between E85 and gasoline is ethanol 50 cents cheaper. I have never seen a difference this high so this makes E85 look better than it is. So today gas cost $2.799 a gallon at the gas station by my house so I will assume that E85 costs $2.299 a gallon. A gallon of ethanol only has 67% of the energy that a gallon of gasoline has. So now off to math land we need to know how many gallons of E85 are needed to produce the same amount of work as a single gallon of gas. Well we need to solve the equation 1=.67 x ??. This is simple algebra simply divide 1 by .67 and we get it takes 1.49 gallons of ethanol to do the same amount of work as 1 gallon of gasoline.

So going back to our example to go 10 miles on gas it would cost you $2.799 but to go the same distance on ethanol it would cost you $3.42 (multiply 1.49 by 2.299). I did a similar calculation yesterday and I will say it again. Wow that is a crappy deal! These calculations did not take into account the fact that the burning of this fuel is less efficient as demonstrated by my dissection of claim 5. Also keep in mind that the production of the corn used is subsidized by the federal government, the blenders also receive a 51 cent per gallon subsidy, and the state of Minnesota subsidizes the ethanol producers so how much in my tax money is going fore each gallon of ethanol, I have no ideal but that wasn't even taken into account here, this again would make ethanol look worse than it really is. I want to know the true cost of a gallon of E85 but have no idea where to begin calculating it.

Claim 8 it degrades quicker:

Yes it does, but how many people are spilling gasoline in water or dumping it in the sewer. This is really a non issue.

Claim 9 The upper mid west has led the nation in E85 uptake:

Why is this a benefit. We just have a good farm lobby that needed something to do with the excess corn they were being subsidized by the government to grow.


If you are going to try and sell some one on something be able to provide sources, analysis and facts, not piss and wind. Let's get rid of ethanol as a general purpose fuel apart from it is renewable it offers nothing, and I believe it detracts more than it offers. Would you rather eat lower cost food and use a lower cost fuel or eat higher cost food and use a higher cost fuel. Ethanol has already created the later, I want to go back to the former.

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