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Pros and Cons of Ethanol in Gas

Chris learns new things and pushes his limits. As a kid, he took the training wheels off his bike because they seemed to be in the way.

The average ethanol content of American gasoline was more than 10% in 2021.

The average ethanol content of American gasoline was more than 10% in 2021.

What Is Ethanol?

Ethanol, ethyl alcohol, is the same type of alcohol that is found in an alcoholic drink. It's often used in motor vehicle gasoline as an additive. American gasoline today contains roughly 10% ethanol.

A gasoline-ethanol mix containing 10% alcohol is called E10. Since alcohol contains less energy per unit volume than gasoline, this fuel composition has a 2-3% lower energy content than straight gasoline. Pure ethanol fuel, E100, has 1/3 lower energy content than straight gasoline: it takes 1.5 gallons of E100 to provide the same amount of energy as 1 gallon of gasoline.

But people are using ethanol-gas blends more, despite the increased volume of fuel needed to deliver the same energy. Why are people starting to use this gas more?

Let's take a look at some of the bad and good about ethanol fuel: how it affects small engines, whether it's good for the environment, whether it's efficient, and how it might affect food prices.

Using Gas With Ethanol in It Decreases Your Mileage

First of all, everyone needs to understand that adding ethanol to gas actually decreases your mileage, and may increase your fuel cost even if ethanol-blended gasoline is cheaper per gallon than straight gasoline.

The New York Times states that E10 gasoline, which is the blend we commonly use in America, actually gives you 2-3 miles per gallon less than pure gasoline. E85 gasoline, a flex-fuel with 85% ethanol, gives you 7-8 miles per gallon less than pure gasoline. A federal agency says using gas labeled E85 (blends of 51-85% ethanol) can in turn reduce your gas mileage by 15-20 percent over E10.

The lower the gas mileage of the fuel, the more fuel you need to buy to travel the same distance. So do not let the lower price per gallon of high-ethanol blends fool you into thinking they will save you money on a trip. This crowdsourced site collects the latest reports on the prices of E10, E85, and pure gasoline.

When I wrote this in 2012, the average price per gallon for E85 was $3.30, and the average price for gasoline was $3.86. My vehicle would get around 21 gallons per mile, unless I am hauling something. Cutting my mileage down by 25% made E85 a more expensive option for me. To drive 21 miles, it would cost me $3.86 at the pump if I used gasoline, and $4.13 if I used E85.

Is Ethanol Bad for Your Car?

Two chemical differences between ethanol and gasoline are that ethanol attracts water and breaks down faster than gasoline. This is not much of an issue with transportation vehicles. But with small engines not specifically designed for ethanol blends, these properties of ethanol can be a huge problem, as suggested in the New York Times article.

Negative Effects of Ethanol in Gasoline

When fuel absorbs water and brings it into an engine, there is a chance that rust will form on the interior of the engine. For obvious reasons, this is bad for any piece of equipment. The particles that get into the gas from rust flakes will clog up the fuel filter sooner or later. These flakes can also damage the pistons, rings, seals, and any number of other components of the engine.

Ethanol increases gasoline vapor pressure, which may cause a vapor lock in the carburetor. This fuel starvation will prevent an engine from starting. This is an issue in higher altitudes and hot weather. Make sure to store gasoline with an ethanol mixture properly and to use it in a timely fashion.

Gasoline with ethanol decreases the life of the engine and its parts. The alcohol can cause engine seals to break down more quickly. Having a cleaning agent like this constantly in a small engine that was not engineered for this fuel mixture simply ages it at a faster rate.

The ethanol in E10 gas breaks down quickly. An area representative for the garden equipment company MTD informed me that E10 begins to break down within three weeks. This breakdown creates clumps in the gasoline mixture which may clog the filter, carburetor, or fuel line. To help prevent this a person can purchase a gas preservative product such as Sta-Bil and add it as directed to their gas. This will help prolong the life of the gas and keep it from harming your small engine as much.

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When I wrote this article ten years ago, people at a local area small engine repair shop told me that the E10 breaking down was the major cause of equipment being sent in. Inspection, diagnosis, repair, and testing generally cost between $50.00 and $60.00 even when the issue was simply bad gas. This repair shop would drain the system and add new gas that has a stabilizer in it after diagnosing the issue.

Both transportation vehicles and small engines have had these issues, though they were more dramatic in the latter. As more new engines, small and large, are specifically designed for ethanol blends, these issues are becoming less common.

One chemical advantage of ethanol is that it doesn't freeze as easily as gasoline, which means ethanol users' gas lines will not freeze during the winter months in many areas with temperate climates.

Why Using Ethanol Is Supposed to Be Good for America

In the United States, ethanol is created from corn, which is the largest crop produced in the United States. U.S. farmers planted 91.7 million acres of corn in 2019, according to the USDA. When this article was written In 2012, annual corn production was worth $15,100,000,000 per year. Approximately 7% of the national corn yield went into making ethanol in 2001 and that increased to nearly 40% in 2011, according to Business Insider. And some of you may be wondering why.

A political reason for preferring ethanol over gasoline is to protect America from being overly influenced by the power of oil-producing countries in the Middle East. If a nation makes decisions for purely political reasons, this is a very good reason.

Also, the use of more ethanol will create more manufacturing jobs for Americans, thus creating a solution for the American worker that is out of work. America helping Americans.

But let's look at some of the other arguments that the government is using to get people really behind this change.

If using fuels with higher levels of ethanol releases less pollution into the atmosphere, most people would be glad to do that to help our world stay healthier for longer. Ethanol is said to be a much cleaner fuel than gasoline. In 2006, according to the American Coalition for Ethanol, Wisconsin had 16 percent fewer high-ozone days than in 1994 when E10 began being used. But other studies predict that ozone levels will actually increase with increased use of ethanol fuel.

It also seems likely that ethanol fuel use reduces carbon dioxide emissions, though it's difficult to describe the impacts of the whole industrial and farming process.

Despite the potential environmental and health benefits, I would say that the change from gasoline to E85 is more motivated by politics than by the environment or health concerns.

Looking More Deeply Into the Benefits of the "Clean Burn"

Is producing ethanol energy-efficient and cost-efficient?

Dr. Pimentel of Cornell argued early in the program that we use more energy to make ethanol than the ethanol will produce. A 2015 report by the USDA (as summarized by the nonpartisan think tank EESI), found, however, that energy efficiency is increasing since the early days of the ethanol fuel boom; that by then, ethanol production for fuel was creating twice as much energy as it consumed, and in some areas four times as much.

Sugar cane is actually a much more cost-efficient resource for creating ethanol. Six times more efficient, actually. But since America does not grow it, we have placed a $0.54 tariff on sugar ethanol imported from Brazil. This leads to Americans using corn ethanol rather than sugar ethanol. Corn ethanol, although less efficiently produced, creates more jobs for the American people.

The ethanol industry was so heavily subsidized by the government that it's hard to tell how efficient is it economically. Up until 2011 there was a tax break of $.51 per gallon from the Federal Highway Trust Fund, which had to be incredibly attractive to corn farmers.

Could this tax perpetuate an increase in corn prices by creating a static demand for corn? I worry about the combined effects of creating a tax break for ethanol and setting a minimum price for corn. The effect is to increase the cost of corn for food production. When I wrote this, feed prices had jumped over the last couple years. Even bird seed increased quite rapidly.

President Obama required that new automobiles being produced have the flex-fuel option in hopes that people will actually use this option and buy ethanol fuel. The more people who use this option, the greater the percentage of the national corn yield that will go towards ethanol gas. And this increases the cost of production of food products, which has to compete in the market with the production of ethanol fuel. It may not be possible to produce enough corn to make the country self-sufficient in vehicle fuel even if humans and their animals ate no corn at all.

An acre of land can produce 328 gallons of ethanol. So in 2011, the total acreage of land used for corn would allow the United States to produce a total of 23,845,600,000 gallons of ethanol in one year, if 100% of all corn was put towards ethanol. If we changed over to E85 we could produce 27,422,440,000 gallons of E85 if there was no waste.

In 2005, the United States consumed 386,000,000 gallons of fuel a day. So if we used all of our corn towards creating E85 fuel, we would be self-sufficient for 71 days.

The Example of the Penny

It's not unheard of for the US to create something that costs more than it is worth. The energy cost of producing fuel reminds me of the United States penny. The penny we use has a face value of $0.01, but in fiscal year 2010-2011 it cost $2.41 for the U.S. mint to produce a penny. Where government is involved, it's complicated to decide what's efficient.

What About Alternative Fuels That Don't Have to Drive Up the Cost of Food?

I am not against alternative fuels. I simply wish that as a nation we would get behind a fuel that is more realistic to produce to be self-sufficient. I would love to see this world be healthy for future generations. I worry about the world my children will live in and try to teach them how to care for what we have. But it seems that the biggest concern many of our politicians have what they can get the American people to believe that will make themselves look good.

Ethanol fuel would be a great idea if it were more realistic. When you create competition between a food staple and transportation, then it doesn't seem plausible that the concept won't increase the cost of food products.

If you have any comments, please leave them. I would be interested in knowing your point of views and opinion. We need a nation of people questioning our nation's goals during this time in history.

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

Questions & Answers

Question: Should the U.S. put 10% of ethanol in their gas?

Answer: With the issues and inefficiency in conversion, I don't think ethanol is a great option to enforce.

Question: Why don't we use more natural gas or propane?

Answer: I would assume it is because of politics as well as supply and demand.

Question: Wasnt ethanol was first blended with gas to replace MTBE which was an additive used with regular gas which was cancer-causing and found leaching into groundwater? At 10 percent, this was a valid solution? I'm not sure about higher rates.

Answer: MTBE is controversial, but I do believe in some countries still used in low quantities. MTBE is not classified as a human carcinogen though.

Question: When it takes a gallon of diesel fuel (Farm tractors and shipping product by trucks), how is Ethanol less polluting to our environment than gasoline?

Answer: There are many studies that say if you look at production from start to finish, then ethanol does not produce less pollution.

Question: Are electric cars crap?

Answer: I would not say that electric cars are crap, although I do think that they will be many advancements because of the early nature of the electric car. And currently, one of the cost factors is the inefficient manufacturing of them.

Question: How much does it cost to make a penny?

Answer: In 2011, it cost $2.41. In 2013, the cost did drop to $1.83 it appears.

Question: How does ethanol as an energy source work?

Answer: It is less efficient than gasoline, but it is still a combustible and therefore functional as a fuel.

Question: Why did you use the long since debunked David Pimental study instead of the Department of Energy studies that prove conclusively that even making corn alcohol is an efficient way to make energy?

Answer: I have also read the Department of Energy Studies that claim that the footprint of making ethanol is not more efficient. With newer technology, it is becoming so, but we are not there yet. These new methods can't support themselves financially either. So in regards to the conclusiveness, it isn't at the time of writing this.

Question: I know we can't get rid of ethanol, but can we cut back on the use of it to save our gas mileages?

Answer: If our society wasn't as political driven as it is, we could get rid of ethanol gas. As an individual anyone can cut back on the gasoline they use. Good advice to help save mileage, environment, and make us healthier people.

Question: In MO, we can get gas without ethanol. If I mix it 50/50 with ethanol gas (making about 5%) is there any benefit like making the gas ok or so Sta-bil will last longer? The issue is with classic cars that aren't driven much. And is ANY ethanol a problem? Should I drain the tanks completely before putting in ethanol free gas?

Answer: I would drain the tank and then add new. In most cases, you can get by with a mild ethanol blend but it would matter on the date of a vehicle and require more specific knowledge.

Question: How will ethanol affect my 1973 AMC GREMLIN’S engine?

Answer: It would matter what engine you have, but I wouldn't want to run ethanol in my vehicles - older or newer.

Question: I don’t think ethanol is a great solution because of the problems with marine and small engines. My friend just replaced the fuel tanks in his houseboat for $15,000. Do you think that makes sense?

Answer: It does make sense in that, I am not shocked that it occurred. But with marine applications, many people do pay a premium to purchase ethanol free gas. This would prevent this from being an issue.

Question: If my Harley is ruined by Ethanol, can I sue the government?

Answer: I am not a legal expert, but my thinking would be they wouldn't be liable at all because there are other choices of fuel. I do know plenty of people who use ethanol gas in their Harley, though.

Question: You forgot to mention that ETOH made from naturally growing grasses, wood chips, ie., Cellulose sources reduces carbon footprint by 30%. Wee will never run out of it and we don't need corn. What's in your wallet?.....Exon?

Answer: You are absolutely correct, although there are no companies that are advancing these resources and to my knowledge no government agencies pushing these sources as well. Last time these methods were used were during the World Wars and there are some individuals who build their own systems for these fuel sources by modifying their vehicles. It could be a great source, but the lack of reality in your statement shows a little bit of bias.

Question: How does ethanol burn cleaner than gasoline?

Answer: Many would argue that it isn't cleaner, but that they burn differently. It has been shown that they both burn higher amounts of different carcinogens.

Question: Why are car companies still building, selling and using combustion motors when the electric engine could have and should have been built and used over 70 years ago?

Answer: Generally, unless there is motivation to change - there is no change. Gas has been the standard and will continue to be the standard, ethanol was a drive mainly for environmentalist reasons. Electrical has pro's and con's as well. There are already issues with our electrical grid in the United States, so major increases to the use of electric may have more negative issues than most people realize. Much more complicated question than you may realize.

Question: Is ethanol a renewable energy resource?

Answer: Ethanol is a by-product and is renewable. There continue to be improvements in manufacturing, but currently it is not an effective process and we could make ethanol after fossil fuel runs out - although that will be tens of thousands of years with current processes. If you want to watch a more efficient and environmentally conscious method, keep an eye on China and electric cars.

Question: I recently road-tripped and noted all the pro-ethanol signage in gas stations east of Utah. I understand, were I a farmer receiving gov't assistance for growing Monsanto corn, I'd want ethanol promoted as well! My question: Is there ethanol in CA gas? And if so, why isn't it a big deal out west?

Answer: There is ethanol in the CA gas. I can only speculate on why it isn't talked on much. I would make the assumption that a lot of the mentality is more democratic and attempting to support a "cleaner" system - and supporting what the government pushes and accepting it as good. There is also more influence from corn farmers in that direction and this would create an acceptance as well. As stated, all assumptions and I can't say there is anything necessarily bad about it - just different than my perspective.

Question: Why should we make ethanol if it is not a great option?

Answer: There are a lot of potentials for it, but politics became involved and pushed this fuel too soon - my personal opinion.

Question: I wonder how electric vehicles compare to regular gasoline and E85, in terms of financial, economic and political impact?

Answer: Watching Tesla, I do not think we are at the point for any major transitions. In the future, this may very well be a great alternative but many advances need to occur with public opinion as well as availability and cost.

Question: Can using 10% ethanol in your gas make your car "ping" and cause engine damage?

Answer: I am not an expert in this area, but I would look instead at oil. Could be a lifter arm that is hitting, but there is very little chance that it is caused by ethanol gas.

Question: How many gallons of water does it take to make 1 gallon of ethanol?

Answer: It takes roughly 3.5 gallons of water to make one gallon of ethanol. This is a little more than it takes to make 1 gallon of gasoline.

Question: Which gas containing ethanol should I use in my Toyota Camry?

Answer: Any that you would like, there are different additives in gasoline but many of those are not a concern to many people.

Question: If ethanol is so great, how come it settles and you need to treat or stabilize it?

Answer: Ethanol is different, I do not perceive it as a cure or more beneficial. It appears that way if you use the benchmarks for gasoline, but that doesn't show the negative of ethanol. A lot of this debate is political motivated and in the near future I believe there will be a shift in industry as transportation changes to electrical transportation.

Question: E85 is the fuel to use for performance because of its octane rating. Makes big horsepower numbers with a good tune. I wish it was more available; I would use it daily. Does the USA population realize the efficiency of that?

Answer: I do not think anyone is arguing this point, many of us are concerned with many of the other issues. Going fast is not a concern to the vast majority of drivers, we are looking for efficiency.

© 2012 Chris Andrews

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