My thoughts on Ethanol in Fuels


Writer:  Ron Knight (Chemist)

In the third quarter of 2012 I was asked for a solution for the very aggressive corrosion that was taking place in the sumps of underground fuel storage tanks. After about 2 years of study, observations and the treatment of 50+ sumps, I have arrived at the following conclusions. Hopefully you will find the following interesting enough to do your own research and form your own educated opinion.

If you research ethanol on the internet, you will find anything that you want to read. One group says how good it is to use ethanol and another group says how bad it is. My suggestion is to look at the author of the article. The “good side” seems to be from corn producers, the Renewable Fuels Association and others that benefit from ethanol sales. While oil producers show up on the “bad side” list so do a lot of equipment manufacturers and motor producers. You may want to take a look at an (old) article written by Mr. Ed Wallace for Bloomberg Business Week. The title is “The Great Ethanol Scam”.

Back when you actually had a choice of buying gasoline with or without ethanol, I drove a VW Passat about 5000 miles with 100% gasoline and 5000 miles with the standard 90/10 blend. The mileage with the 10% ethanol was 12% less than with 100% gasoline. I drove a Ford F150 about the same number of miles and the mileage with 10% ethanol declined 15%. I drove a Chrysler van 3000 miles and the mileage declined 17%. Using my F150 as the example, let’s look at what means. My F150 got 22 mpg with 100% gasoline and 18.7mpg with the 90/10 blend. If I drove 10000 miles with 100% gas, I would have used (10000/22) 455 gallon of gasoline. Driving 10000 miles at 18.7 mpg, I used (10000/18.7) 535 gallon of the blended fuel. Remember out of the 535 gallon of blended fuel (90/10) only 90% is gasoline. If you take 90% of 535 gallon that means that I used 481.5 of 100% gasoline. The point here is that instead of saving petroleum, I actually used 26.5 gallons MORE than I would have used without the ethanol.

The website states: “Vehicles will typically go 3% to 4% fewer miles per gallon on E10 and 4% to 5% fewer on E15 than on 100% gasoline”. HOWEVER, two paragraphs after that statement it also states: “MPG. Due to ethanol’s lower energy content, FFV’s (flex fuel vehicles) operating on E85 gets roughly 15% to 25% fewer miles per gallon than when operating on regular gasoline, which typically contains about 10% ethanol.” From my experience (as noted above) the second statement is closer to the truth than the 4% to 5% statement.

If you “look around” on the fuel economy website, you will find a section that compares the mileage of cars using 90/10 fuel and what mileage that you can expect if that car uses the 85/15 blend. I randomly selected a 6 cylinder, automatic 2014 Chevrolet Impala. According to the website the combined mileage using the 90/10 fuel is 22 mpg with an average annual cost of fuel at $2350 while the combined mileage using the 85/15 blend is 16mpg with an average annual cost of fuel at $3200. If the annual number of miles driven were 15,000 the car using the 90/10 blend would use (15000/22) 682 gallons while the car using the 85/15 blend would use (15000/16) 937 gallons. Since the 90/10 blend contains 90% gasoline and 10% ethanol the actual gallons of gasoline used would be (682 x .9) 614 gallons of 100% gasoline. The 85/15 fuel contains 85% gasoline and 15% ethanol so the actual gallons of gasoline used would be (937 x .85) 796 gallons. In this case the car using the 85/15 blend will use 30% more gasoline. So much for the rationalization that the reason to add ethanol to gasoline is so that less fuel (and imported oil) will be used.

Most ethanol is produced from corn. The average calendar year cash corn price/bushel received from Iowa farmers was:
Year Price/bushel
2000 $1.78
2005 1.90
2010 3.86
2013 6.22
In 2000 less than 5% of the US corn crop was used to produce ethanol. In 2013 that number jumped to 40%.

On January 2004 the average price of a pound of bacon was $3.16; June 2014 is was $6.11

In 2000 the average cost of Layer (chicken) feed cost was $125/ton
In March of 2013 (the latest figures I could find) the average cost of the same feed was $324/ton
This is an increase of 259%

The “standard” diet for chickens is: 67% corn, 22% soybean meal, 8% limestone and 3% other

The US Chicken Wholesale Price (Georgia Dock) in USD/kg was 1.922 in June 30, 2010 to 2.444 on June 30, 2014. That is a 27.2 % increase in the wholesale price.

The Earth Institute-Columbia University stated:
“The amount of water it takes to produce ethanol varies according to how much irrigation is needed for the corn, particularly since row crop agriculture for corn is the most water consuming stage of ethanol production. In Ohio, because of its sufficient rainfall, only 1% of the corn is irrigated while in Nebraska 72% of the crop is irrigated. It takes 19 gallons of water to produce a bushel of corn in Region 5, 38 gallons in Region 6 and 865 gallons in Region 7. The Baker Institute estimates that producing the corn to meet the ethanol mandate for 2015 will require 2.9 trillion gallons of water.” The average person in the US uses about 32850 gallon/year so it would take (2.9 trillion/32850) 88.3 million people to use that much water in one year. That is the entire populations of: California, Texas, New York and Arizona added together.

Located in the last paragraph on page 8 in Oil Express Volume 37, Issue number 33 dated August 25, 2014 Kristy Moore, vice president of technical services for the Renewable Fuels Association was quoted as saying (referring to a NIST study on the effects of ethanol on corrosion in the sumps of UST’s), “the conditions of the NIST research ‘could not occur in the marketplace today.’ Moore pointed out that ethanol has been ‘successfully blended, distributed, stored and dispensed at retail fuel stations for decades with no equipment corrosion issues’.”

The State of Tennessee, Division of Underground Storage Tanks has done extensive research on “Ethanol Related Corrosion in Submersible Turbine Pump Sumps”. There is a study of a March 2011 ASTSWMO Meeting available online. If there was any doubt that the addition of ethanol to gasoline had a dramatic and adverse effect on the sump components, this study will remove all those doubts. On page 3 there is a photograph of a non-ethanol gasoline sump that is 11 years old. There is minimal corrosion. On page 4 there is a 4 June 2008 photograph of an E-10 ethanol sump that looks new. To the right of that is a 1 November 2010 photograph of the same sump that shows severe corrosion. On page 5 is a 9 March 2010 photograph of a new premium sump and to its right is a photograph of the same sump dated 25 August 2010 (169 days later) showing severe corrosion. The report also includes a study showing the effects of sump vapors on a wire(s) that was in a sump(s) for 68 days. The percent (by weight) of wire loss went from a low of 0.43% to a high of 16.8%. This means that up to 17% of the actual wire “corroded away” in only 68 days. One wire “disappeared” in only 13 days. Page 21 of the report states: “A link exists between ethanol in motor fuels and the corrosion of metals in the sumps of an underground storage tank.”

There is a section of copper tubing connected to the leak detector. The first time that I looked into a sump I ask the station owner, “What does that piece of blue wire do?” As it turns out the blue wire was actually the copper tubing that was covered with copper acetate which is a form of corrosion. When copper corrodes it is subject to pitting corrosion. As the name indicates pitting corrosion creates pits that will continue to grow both larger in diameter and deeper into the (in this case) copper. The leak detector works by taking a small amount of fuel and putting it under pressure. If the pressure does not drop, the fuel sample is returned to the storage tank via this copper tube and the fuel dispenser turns on. If there is a hole in the tubing the sample of fuel can leak into the sump instead of returning to the storage tank. Working with a strength of materials handbook, I calculated that the ultimate strength of copper tubing is reduced by 15% of there was a pit 0.005 inches in diameter. I “Googled” diameter of a human hair and depending on the hair color the answers I received was from 0.001 to 0.004 inches. It would not take a very large pit for the tube to rupture.

A public release on 1 October 2013 by NACE International entitled, “Solving ethanol’s corrosion problem may help speed the biofuel to market” states “One of the most important concerns with regard to the integrity of pipelines and tanks is the propensity of ethanol at concentrations above 20 volume percent in gasoline to cause cracking of steel, explains Narasi Sridhar, vice president, director of the materials program at Det Norske Veritas. This phenomenon is called stress corrosion cracking.” Please note that the study states at concentrations above 20 percent not the 10 or 15 percent that is currently under consideration.

I have worked with the effects of corrosion for 25+ years and I have been formulating corrosion preventative compounds for 11 years. I have never experienced the rapid onset of severe corrosion as I have observed in the sumps of underground storage tanks that are exposed to ethanol.

The above 2 pictures are not unusual. The top picture shows the copper acetate on the copper tubing, the large flakes or tubercles seen on the other components is concentrated cell corrosion. This type of corrosion often occurs where the surface is exposed to an electrolytic environment (i.e. acid). The second picture shows a new pump next to a two year old pump. I have looked at 50-60 sumps and treated about 25. I have at least 50 pictures that look like the above two.

I started formulating a product to solve the problem almost 2 years ago. After a number of attempts I decided that there is not a product that will prevent this severe corrosion. There are a number of problems that cause the sump corrosion and it takes several products to solve it. I have developed a 4 step process where each of the four steps solves a specific problem. Un-treated sumps are corroding in 4 months and so far we have passed 7 months without corrosion.

At this point we know that:
1. Ethanol decreases gas mileage
2. The corn used in ethanol production takes away from human consumption
3. The corn prices have increased over 300% since 2005
4. As a result of higher corn prices, chicken feed has increased 259%. The price of chicken has risen 27%
5. Bacon prices have risen 193%
6. Corn/ethanol production uses vast amounts of fresh water
7. Corn requires a large amount of nitrogen, which can lead to runoff/water pollution.
8. Ethanol/gasoline blended fuels shorted sump equipment life from 10/11 years to 2 years.
9. Ethanol at concentration above 20% can lead to stress cracks in pipes/pipelines.

I have heard people say, “If ethanol really does all of the above, why is it used?” Why is the government promoting E10 and now E15 Flex Fuels”?


Follow the money!

The federal government collects an excise tax of $0.184 PER GALLON and the last time the tax was increased was 1993. In addition to the federal tax, state and local governments collect additional gasoline taxes and they are also PER GALLON. The average US total tax is about $0.50 per gallon with California being the highest at a total of $0.713 per gallon and the lowest being South Carolina at $0.352. The Congressional Budget Office (CBO) has stated, “Although vehicles will travel more miles in the future (therefore consuming more taxable fuel), rising fuel efficiency standards and congressional refusal to increase the fuel tax means that the fund receives less money.”

I live in Florida and lets take the 2014 Chevrolet Impala that was used in the above example and that I drove 15,000 miles/year:

From my actual driving experience the least drop in mileage using the 90/10 blend instead of 100% gasoline was 12%. If 100% gasoline was used in the Impala the mph would be approximately 25mpg.

Fuel MPG Gallons of fuel used Gallon of gasoline used

100% gas 25 600 600

90/10 22 682 614

85/15 16 937 796

Fuel Fed tax (.184) Florida/local tax (.36) Total tax

100% $110.40 $216.00 $326.40

90/10 $112.98 $221.04 $334.02

85/15 $146.46 $286.56 $433.02

Consider the following:
Corn ethanol production uses unbelievable amounts of water. The prices of corn and related foods that use corn have increased dramatically. The effects of ethanol and ethanol vapors has reduced the life of fuel tanks and related equipment by as much as 80%. There are probable environmental concerns with fertilizer runoff. The newer vehicles get much better fuel mileage. Fuel tax revenues are down and money from the general fund are being used to build/repair highways and congress will not pass legislation for an increased federal tax on gases.


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