Carbon Footprint of Ethanol: Does Corn Ethanol Reduce CO2? Shocking Facts

Georgette Kilgore headshot, wearing 8 Billion Trees shirt with forest in the background.Written by Georgette Kilgore

Carbon Offsets Credits | April 4, 2024

Woman wondering about the carbon footprint of ethanol, asking does corn ethanol reduce co2, and what about the production of ethanol gas, e85, and how do emissions compare between ethanol vs gasoline, and what are the pros and cons of ethanol?

Time and time again, biofuels have been lauded for being cleaner alternatives to fossil fuels, and ethanol is one of them, leading many people to wonder, what actually is the carbon footprint of ethanol?

Such sources have been known to cause less GHG emissions, and more people are starting to turn to them as safer and cleaner fuel sources.

But, there’s a lot to learn about ethanol’s carbon footprint.

You may know all about gasoline or diesel as the most commonly used in the transportation world, but did you also know that ethanol is becoming an excellent transition to clean energy, but it also comes with a pretty fair share of downsides.

This complete guide explains ethanol’s potential as an alternative energy source, and also examines the real carbon footprint of ethanol, answering the question, does corn reduce CO2?

Emissions Difference Between Ethanol and Gasoline (Real Truth)

Although many people focus on miles (or kilometers) driven, when comparing gasoline with ethanol, the emissions generated during combustion are very similar.

Gasoline emits approximately 19.59 pounds when one gallon is combusted.

Ethanol emit 18.94 pounds of emissions when one gallon is combusted.

These emissions amounts are very similar, and the difference comes from how these materials are produced. One is refined from fossil fuels, the other from renewable resources.

What Is Ethanol?

For over a decade now, governments have tried their level best to reduce the level of emissions that come from fuels.

Fossil-based fuel sources have been in use for the longest time, and they have only proven how detrimental they can be to the environment.

Bar graph that shows the life cycle emissions of energy sources such as coal, natural gas, biomass, solar, geothermal, hydropower, nuclear, and wind.

The only option to lower the carbon footprint of fuels is by turning to more sustainable alternatives, and ethanol seems to step up to the plate to make this happen.

But first things first, what exactly is ethanol, and how is it used as a fuel source? Ethanol is basically alcohol, the same thing you will find in virtually any alcoholic beverage, and the process of making it fuel and alcohol is literally the same.

Ethanol is also called ethyl alcohol and is a product that comes from biomass.

It is the substance that comes from fermenting biomass like corn, sugarcane, and grains or sometimes paper waste and rendered meat. Its most popular use is in the making of alcoholic drinks, but did you also know that it can be used as a fuel source?

So, what happens is that the biomass is usually blended together with gasoline in a bid to oxygenate the fuel that comes out of the pump at the station.

Apart from that, ethanol is also known to be used independently as fuel, all on its own without blending with other fossil fuels. But, when the ethanol is converted to fuel, the manufacturers have to mix in some more chemicals, which makes it hazardous for human consumption.

It is common for people to confuse ethanol with methanol;13 What’s the difference?

Simply put, methanol is alcohol that is made from wood, which means that from the get-go, it is already poisonous in its rawest form. It can also be used as a fuel, but only on extremely high-power engines and rarely, if ever, in normal street vehicles.

Ethanol has been used in vehicles for quite some time now, and history has it that it started in the early 1900s.12

Henry Ford created the Model T to run on a blend of ethanol and gasoline, and that was the first record instance of its use. At that time, roughly around 1908, gasoline was not that common, but ethanol was.

Farmers could easily produce it from the crops on their farms and at a very cheap cost. Another instance of ethanol use was during WW2 when gasoline was being rationed.

Fast forward to present-day America, about 97% of the gas that you will find at pumps contains ethanol. It is only the amount or rate that varies in accordance with particular state regulations, although you can still be able to find ethanol-free gasoline if you want.

However, in general, virtually all the gas that will be sold to you in the US will contain at least 10% ethanol.

Production of Ethanol: How Is Ethanol Produced?

Ethanol has so many benefits, and car companies and even governments vouch for its use.

As of 2021,14 the US was the leading producer of biofuel, followed by Brazil.

Country Biofuel Production (petajoules)
USA 1 435.8
Brazil 839.5
Indonesia 311.9
China 142.7
Germany 121.2
France 107
Thailand 89.8
Argentina 85.6
Netherlands 84.6
Spain 71.9

Now that you know what it basically is, it is obvious that your next question is going to be, how is ethanol produced? How is it possible that corn or any other biomass is able to convert to become clean fuel?

To answer your question, first, know that ethanol does not come from natural sources. But it has to be produced from somewhere, right?

Graphic that shows the biofuel production per country such as USA, Brazil, Indonesia, China, Germany, France, Thailand, Argentina, Netherlands, and Spain.

In this case, it is kind of the same thing that happens during the manufacture of alcohol. It is quite simple really; you know that the fermentation of sugar always leads to the creation of ethanol.

You are also aware that plants that have got a high sugar content can be easily converted to starch.

Some of these plants include cane, wheat, corn, and barley. To put it very simply, there has to be at least the fermentation and distillation process in the plants above for ethanol fuel to form.

Maybe you are curious, thinking, what usually happens in the plants to create ethanol? You will be shocked that it is a rather simple process that tends to start with the grinding of the plants that are needed in the production.

When that is done and dusted, the residue that is left or the ground substrate is then able to be converted to sugar or starch. Basically, that is the raw product that will come in handy for the entire process.

By fermenting, the sugar can now transforms into the final product, which you now know as ethanol. It is also pretty common for yeast to be included in the steps to help catalyze the fermentation, basically exactly what happens in the manufacture of alcohol.

Finally, there is the last stage, or the icing on top, where ethanol goes through distillation and purification, and with that, it will be good to go. Perhaps you have noticed that it is a rather short process, right?

Thich is one of the advantages of ethanol because it doesn’t cost that much to manufacture in the first place in comparison to other fuel sources. All you have to do is to squeeze out the juice from the plant, ferment, then distill, and voila, kind of like the alcohol-making process.15

What Is Ethanol Used For?

Imagine if you put ethanol in a clear jar. It will most likely pass off as a clear harmless liquid, but on closer look, its distinctive smell will definitely give it away.

There is ethanol in its purest and rawest form, which is harmful, and then there is the processed form which is more fit for human consumption. As you are yet to see, the substance is quite versatile with so many applications; take a look at some.


Did you know that ethanol is a pretty common ingredient in skin care products? That it can be used in plenty of ways in cosmetic products.

For one, manufacturers use it as a preservative to hold together the ingredients used in creams.4 Secondly, it is also vital in improving the ability of hairspray to latch onto the hair.


Ethanol is one of the main components that are used in wet wipes and hand sanitizers purely based on the fact that it has antifungal and antibacterial properties. It dissolves the microorganisms’ lipid layers and kills them in the process.


Ethanol is famous for being quite an excellent solvent that seems to effortlessly mix in water. This is very vital in the manufacturing process because it can be added to paints, varnish, cleaning products, and so many other substances.

As pointed out earlier, it also works amazingly in making hand sanitizers since it dissolves well, and a bonus is that it has virus and bacteria-killing properties.


You can flip over the wrapping of your favorite food item and see that ethanol is one of the ingredients. It is very common because it also works as a food additive.

You will likely see it being used in food coloring and additives like vanilla extracts because it also improves the flavor.

Alcohol Manufacture

You should know this by now because this is the most famous use of ethanol, and it is a main ingredient in the alcohol manufacturing process. Perhaps it is important to note that ethanol is not actual alcohol; it is only an ingredient.

As such, it is completely not safe for direct human consumption, and you should never, under any circumstances, drink it pure. It has some rather devastating effects ranging from blindness to death.


Probably the largest single use of ethanol is how it is included in engine fuel. Brazil is the world’s leading user of ethanol fuel, and that explains why it is also the largest producer of ethanol.

The US and most other countries use just 10% ethanol in their gasoline, but the rate in Brazil stands at as much as 25%.

It is also pretty interesting that ethanol was also used as rocket fuel, especially in the very first German V-2 rockets in world war 2, when they realized that when mixed with water, it could effectively lower the temperatures in the combustion chamber.

Is Ethanol Bad for Environment?

If you are talking about the comparison between ethanol and fossil fuels, then ethanol is definitely better for the environment.

On the other hand, it still has GHG emissions, sometimes higher than those from other renewable energy sources like solar and wind power, which impacts the carbon footprint of ethanol.

However, in general, ethanol gas production and usage is friendlier to the environment, unlike gasoline.

What Is the Carbon Footprint of Ethanol? Ethanol CO2 Emissions

What is a carbon footprint? You may ask.

The carbon footprint of an activity usually refers to how much the said activity has impacted the environment,16 specifically how it has contributed to climate change.

To put it more simply, the carbon footprint is the measure of how much greenhouse gasses (or carbon dioxide, to be more specific) a certain activity emits within a certain period of time

A graphic that portrays the difference between ethanol and gasoline CO2 emissions.

When talking about carbon footprint, always think of it as a measure of how much carbon a certain activity emits. There are emissions everywhere from almost everything humans do, from household emissions to those from driving a car and so on.

If you are environmentally conscious, you will know that everything has an impact; that is why the planting of trees is so important.

Tree’s carbon sequestering abilities kind of nullify the effects of the emissions, which explains why lobby groups are always advocating for tree planting. If you want to know the impact you have on the environment, you should learn the carbon footprint of electric cars vs gasoline, or if not, go online to find an elaborate and easy-to-use carbon emissions calculator that will do the job for you.

Now, onto the most important question, what exactly is the carbon footprint of ethanol? Ethanol can be used the same way as gasoline to make the engine run.

The two can be blended together up until a certain percentage, and there is a way to denote that. For instance, if it is pure ethanol, it will be denoted as E100, but the most common mixture can be E10 (10% ethanol plus 90% gasoline), although there are also E85 and E15.10

According to the US Energy Information Administration,17 single gallons of ethanol produce 4% fewer emissions in comparison to gasoline. And for E85 emissions, the rate of emissions for the vehicle models is 22% lower, that is, if you compare them with gasoline.

When you burn one gallon of ethanol (E10), it will result in the emission of 8,595g of carbon. In addition to that, when you drive a single mile on an engine running on E85, it will emit approximately 315g of carbon emissions (depending on the mileage of the vehicle.

Activity Carbon footprint (amount of CO2 emitted)
Burning a gallon of ethanol (E10 or E85) 8,595g (18.94 pounds)
Driving a mile (E85) 315g

That is the estimated carbon footprint of burning ethanol but it goes deeper than that.

If you want to truly understand the environmental impact of the use of ethanol, it is best to know the life-cycle analysis and the emissions at each stage.

Life-cycle assessment (LCA) takes into account virtually all the carbon emissions from the product’s manufacture to its end of life, and it is what companies use when they want to make their manufactured products more sustainable.28

What Is the Carbon Footprint of Ethanol Production or Extraction of Corn for Ethanol?

The life cycle assessment is more or less the carbon footprint calculation of the entire life cycle of ethanol.18 To put it more in perspective, it basically starts at the extraction stage, where the raw materials are used in the production of ethanol.

That is the ultimate first stage which involves the growing of the crops that will later be in use, then of course the harvesting and their transportation to the plant.

These factories are where the magic happens, where the biomass is processed for conversion to fuel in the fermentation process which is the whole point of the conversion (where starch is transformed into ethanol). Did you know that this process can go in two main ways?

Graphic that shows the products produce from corn such as tires, aspirin, ethanol biofuels, creams and perfume, drywall, toy crayons, spark plugs, nappies, sanitizers and hand soaps. toothpaste, and toilet paper.

It is fascinating that there is dry or wet milling, and sometimes there can also be a third way, cellulosic biomass. What is the difference, then? How they handle the grain.

Dry Milling

It is kind of incredible how 90% of the ethanol manufactured in the country is produced via this method, which basically makes it the most common. Here, the corn is ground first, and then water is added to create a mash.

It is this mash that is later mixed with catalysts to speed up the process of converting the starch to sugar.

After that, the mixture will be taken for boiling and cooling before the addition of yeast, which again speeds up the creation of alcohol. When the fermentation process is done and dusted, the ethanol goes through distillation and dehydration, and then, a small amount of gasoline is added before the fuel can be taken to the gas pump stations.

Wet Milling

This process basically produces the same thing but in a slightly different process, especially for the initial part. In the first step, the grain harvested is soaked to get the components of the corn to separate from each other.

The grinders have to do the hard part of separating the gluten and fiber from the starch, with the intention being to get the starch to fully isolate.

It is the remaining starch that will undergo the same entire process of dry milling. It will be sent to the fermenting location, where they will add yeast and start collecting the resulting ethanol, which will be mixed with gasoline and then transported to places where it is needed.

Cellulosic Biomass

This is kind of a more complicated process than the above two because here, the cellulosic feedstock is transformed into ethanol, and that happens in two main processes. It can be biochemical or thermochemical.

For the biochemical process, the matter undergoes pretreatment to bring out the hemicellulose sugars, after which hydrolysis takes place to help break down the matter into sugar, now making the fermentation process way easier.

On the other hand, there is also the thermochemical process which involves the use of chemicals under heat to make the biomass release syngas, which is literally a blend of carbon monoxide and hydrogen. Later on, the syngas is mixed with an enzyme that helps speed up its conversion to ethanol.

What Is the Carbon Footprint of Ethanol Transportation?

After ethanol is produced, it has to be transported to various regions where it will be used. You also have to factor in the emissions caused by transportation to understand the carbon footprint of ethanol because it is also part of the steps in the life cycle.

To calculate the emissions from the transportation, you must know where the ethanol is being produced, where it is going to be consumed and measure the total distance between those two places.

For example, the US exported 40% of the total amount of ethanol it produced to Canada and Brazil,19 and that can be the basis of the carbon footprint calculation. Take, for instance, the distance from the US to Brazil as around 4,200 miles and 1,400 miles all the way to Canada.

Obviously, the amount of emissions will increase the longer the distance gets, meaning the exportation to Brazil will have a bigger carbon footprint.

Image if the front of a green race car using Ethanol gas with E15 15% Ethanol printed on its hood.

(Image: Doug Peters30)

Look at it this way, there will be more emissions considering that the distance is longer, and there will probably be more modes of transport between the plant or factory to the final destination of ethanol.

If the ethanol was used locally and didn’t have to be transported across countries, it will have a way lower carbon footprint.

What Is Gasoline Made Of?

You can’t get far driving without gasoline in your car or an empty tank. You need something to fuel your engine, and that is why you make regular rounds to the gas station to fill your tank.

But what exactly is gasoline, and where does it come from? Of course, you know by now that gasoline is not naturally occurring, and neither is it a renewable fuel source.

The gasoline that you know and use almost every day is a substance that comes from crude oil or otherwise known as petroleum.11 This matter that is the source of gasoline is basically a hard thick substance that comes from deep in the ground, a long distance beneath the surface or, to put it simply, gasoline is a fossil fuel.

You see the plant and animal matter from millions of years ago; this is what accumulates, and the remains are now converted to crude oil that can be mined for refining to manufacture gasoline and other substances. But how is that possible?

The remains that were left on the earth’s surface from millions of years ago and over time were covered up by layers upon layers of rocks and sediments.

As the layers keep piling up over so many years, a lot of pressure builds up under the ground. The pressure plus the heat on the dead plant and animal matter is what causes the creation of liquid matter that becomes hydrocarbon, crude oil, or petroleum.

A graphic that shows the ethanol distillation process that consists of thermometer, fractionating column, heat, water out, mixture of ethanol and water, condenser, and cool water.

This material is basically made up of carbon and hydrogen molecules, and they are present in chains that come in different lengths.

You will realize that the more carbon molecules in the chain, the longer it will be. The lengths of the chains are the ones that determine what the crude oil will be used for, interesting, right?

For instance, the short chains that consist of 1-4 carbons are used to make petroleum gasses known as ethane, methane, butane, and propane.

On the contrary, the longer hydrocarbon chains that consist of 5-7 carbons are used to make solvents for dry cleaning and paints. There are also longer hydrocarbons of 7-11 that make gasoline, which is now the main component that is used to make fuel.

Basically, the more the carbons, the heavier the product formed. There also exist chains of more than 12 carbons that come in handy in the production of engine oil, kerosene, and solid petroleum forms like wax and tar.

You may ask, how do experts know how to separate the chains and make them different products from crude oil? It is quite simple really; scientists take advantage of the boiling points of different chains.

Thanks to distillation at oil refineries,20 it is very easy to separate out the lightest from the heaviest materials.

The crude oil is subjected to heat at the plant, where the temperature gradually increases, all the while collecting the substance that boils off at different points. The evaporated materials and various stages are then collected and condensed, leaving various products that have come from a single crude oil matter.

Gasoline has been used for the longest time now to help power engines, but the whole concept of mining, refining, transportation, and even usage of the final product has been faulted for having a negative effect on the environment. Governments have done a lot to help reduce the carbon footprint caused by vehicles, and one viable alternative turns out to be the abandonment of gasoline altogether in exchange for the use of electric cars.

Many innovative car companies have come up with unique and clean electric vehicles that are excellent for the environment. If you are wondering what is the carbon footprint of electric cars vs gasoline, know that the difference is more than double that it is, in favor of electric cars.

However, there is some debate about how much emissions they actually save, when charged by fossil fuels.

What Does Ethanol Do in Gasoline? Corn in Gasoline

Statistics show that more than 90% of the gas used in the US contains a certain percentage of ethanol. But why is there ethanol in fuel anyway?

Well, experts discovered that adding it to fuel actually increased the octane rating that gasoline had. Basically, when the octane rating is high, the pressure of fuel ignition also goes up.2

In previous years, when lead was added to fuel, the experts pointed out the fact that it had a connection to liver and heart diseases and could also lead to reduced IQ. Therefore, there was a dire need to make a switch to a safer option.

This alternative had to be clean and had to work at the most optimal level, such that the engines would still be able to run as smoothly as they used to do before.

A graphic that shows the difference between ethanol and gasoline in terms of composition, source, environmental friendliness, energy production, and engine damage.

Several modifications were seen as necessary to make it all work. They literally had to reduce the compression and go for other enhancements, but ethanol was kind enough to step in at the right time, all thanks to being very combustible.

The best part about using ethanol was the fact that its higher octane levels do nothing but ensure that it burns efficiently and doesn’t explode, meaning a lower detonation level.

It is now pretty much self-explanatory why you will have to pay more for premium gas than the regular kind. In comparison to the low-grade gasoline, the one with added ethanol is much less likely to detonate, but still, remember that there is a political side to all this.

For starters, you know that ethanol comes from corn, wood chips, cane, and other crop waste, and most of all that biomass comes from a very strong political state in the country.

Take Iowa, for instance, a state that has got the credit of contributing $5 billion USD to the economy and providing thousands of jobs in the sector of producing corn for ethanol. History has it that politicians have to support the mandate for continued use of ethanol in gasoline for them to win elections in Iowa.

There is a long story about when ethanol was first used in the US, and it doesn’t come as a surprise that it is even mandated by Congress. The first instance was during the enactment of the Clean Air Act of 1990,21 and then fast forward to the Renewable Fuel Standard of 2005.

A little later, in 2007, congress further increased the targets of the RFS to 36B gallons by the year 2022.

The consequence of this was that there was a rapid increase in the amount of ethanol pumped to gas stations; the numbers say that there were 13B gallons by the year 2014. As of now, ethanol fuel has grown to become one of the largest exports by the country.

In 2011, more than 30 million barrels were sent over to countries like Brazil, China, and Canada.

While there is the E10 version of fuel ethanol, you will be shocked that the largest use is E85 or otherwise called flex-fuel. That means that 85% of the fuel is ethanol, while the rest is gasoline.

So many in the automotive field support this version and use them in a massive range of cars although the same models are also still able to run purely on regular petroleum.

Is Ethanol a Fossil Fuel?

Ethanol is very different from other fossil fuels just from the composition of the source. While fossil fuels come from the earth’s surface in the form of crude oil, ethanol gas comes from crops.

Corn, cane, wheat, and other plants are biomass sources that create this fuel source because the sugar content gets fermented to lead to the release of ethanol that you now know.

Negative Effects of Ethanol in Gasoline

There are certainly both the good and the bad sides of blending ethanol in gasoline. While it may be able to reduce the rate of emissions, there are still some concerns about it having some negative effects.

The main reason to blame for this is the fact that the final stages of the blending of ethanol and gasoline usually involve the addition of water too. So here are some downsides to that.

Ethanol Is Hygroscopic

This is one of the main issues related to adding ethanol to fuel. From your chemistry, you know how ethanol easily absorbs water, which has presented a lot of problems, especially water contamination of fuel.

While ethanol and water effortlessly blend in because they are miscible, the case is different for gasoline and water.

The liquid is heavier than fuel, and as a result, it usually pulls down the ethanol. At some point, the water and most of the ethanol sink to the bottom part of the fuel chamber and lead to a full-on separation.

This often results in issues with the quality of the fuel.5

Ethanol Can Be Corrosive

Again, from your chemistry, you know that ethanol can easily corrode the fuel systems. Basically, it reacts with oxygen in the air.

So what this means is that it is able to form some sort of acidic compounds that can in turn effortlessly corrode the internal parts and cause the engine to wear out way faster. As if that is not bad enough, you can imagine what it means because the corrosion is even made worse by the fact that there is also water involved.

This has a huge impact on any metal type that comes in contact with it, which is virtually the entire system. And that includes the aluminum engine and all other metallic parts you can think of that it is in close contact with.

To avoid this, you will definitely have to use something that inhibits corrosion.

Ethanol Can Contribute To Fuel Oxidation

What is the oxidation of fuel? This is actually a chemical reaction that tends to take place when there is exposure to oxygen, and that has the effect of making the fluid very unstable and potentially making it lose some of its volatility.

And it goes without saying that that is the last thing you want because low fuel volatility has some terrible effects on the car.22 You will have to deal with a poor rate of combustion and, unfortunately, overall poor performance.

There are so many downsides to this because starting your car will be affected, and it won’t run as easily as it is supposed to. The more the fuel oxidizes, the more varnish and gum form, and it may even result in engine damage.

Only additives can help at this point to help increase the shelf life of ethanol fuel and generally improve oxidation stability.

Ethanol Mandate 2022

The Environmental Protection Agency (EPA) set one of the highest ethanol mandates in 2022 at a shocking 15.25 Billion gallons. This is one of the efforts that the agency is making to maybe strengthen the already existing Renewable Fuel Standard.

At present, ethanol is way cheaper than gasoline, and it goes without saying that it will be quite a reprieve for customers at the pumping stations.

According to the EPA, this is nothing but a bid to create more options for the people and give them cheaper fuel services, all thanks to making homegrown biofuels more readily available.

One of the upsides to this is the fact that there will be reduced reliance on oil, and finally, the RFS goals will get back to the spotlight after all those years of struggle.

Screenshot from The Environmental Protection Agency website, showing yellow arrow pointed at the title Proposed Renewable Fuel Standards for 2023, 2024, and 2025.

(Image: The Environmental Protection Agency29)

The move to increase the amount of corn ethanol that is blended in gasoline has welcomed a fair share of praise and condemnation from various groups. The EPA still stands its ground regardless, stating that this will be a game changer in the fuel sector because there will finally be more options for the consumer, and the country’s energy sources will also be diversified.6

Together with the ethanol mandate, EPA has also put forward more proposals for more adoption of biogas in farms and the use of biomass to power vehicles. At least, for the first time ever, the body has set its own numbers and not those provided by Congress.

They seem to have a very clear goal in mind, the fact that they want to help reduce the amount of emissions into the environment that has impacted climate change.

The use of ethanol encourages this, and it helps that it is now a huge part of the economy. Imagine it taking up almost 40% of the entire country’s corn supply.

In addition to that, it has enhanced energy security and significantly lowered the price point of fuel. The only challenge in EPA’s agenda is coming from lobby groups who are heavily condemning the use of ethanol-blended fuels citing that it has several negative effects on the environment.

They also have some very strong points that cannot be ignored. According to various environmental groups, they are certain that the increase in ethanol use will have some devastating effects on ecological systems.

Growing all the corn that will meet the demands for these new quotas will lead to farming-related pollution.23 Groups in the oil sector are also joining in on the conversation, stating that increasing the percentage of ethanol in the blend could potentially lead to damage to vehicles, especially the older models.

Ethanol Vs Gasoline

Looking at the ethanol mandate and how much the blending of the two has affected the economy, you can’t help but wonder, which is better than the other. Now that ethanol is becoming a strong part of the fuel industry, does it mean that it is way better than gasoline, and will a time come when there will be a higher percentage of ethanol than regular gas at the pump?


This is probably the main difference between the two, their composition or what they are basically made up of. Starting with ethanol, it has very different properties in comparison to gasoline.

Scientists will tell you that it mainly comprises molecules of ethyl alcohol, meaning alcohol molecules.

But on the other hand, gasoline fuel is composed of various molecules of hydrocarbons, given that it is sourced from crude oil. That is expected because you are likely to find in it an impressive number of hydrocarbon molecules, including ethylbenzene and heptane.


Another rather glaring difference between the two is based on where they come from. Experts source them from two entirely different sources, and it goes without saying that while ethanol is renewable, gasoline comes from a non-renewable source, and there are always going to be concerns about it depleting.

So, where do the two come from? Ethanol is a product of the fermentation of plant products. It comes from sugar or starch crops like corn and cane.

Squeezing and processing these plants in factories and fermenting and distilling them gives you a supply of ethanol from clean and sustainable sources.

On the other hand, the source of gasoline is entirely different. It comes from beneath the earth’s crust, formed by dead plant and animal matter from millions of years ago.

This matter is otherwise called crude oil and is the source of other fuels like kerosene and diesel, all with different boiling points.

Environmentally Friendliness

There has been a lot of debate online about which one is better for the environment than the other, but there seems to be one conclusion. Although both of them have an impact on the environment, ethanol seems to carry the day when it comes to being the friendlier option.

With ethanol, you can tell that it definitely has some upsides.

Starting with the source, how it comes from plant material, and how it is processed using very few steps in comparison to gasoline. It is also a bonus that it usually burns up completely, which is perfect for the environment.

On the contrary, gasoline doesn’t really help its own case because it is harsh on the environment just from the source and all the way to its usage.

It has to be mined from deep in the ground, and the extraction is known to have quite a high carbon footprint. It’s not just the high emissions from mining; there is also the processing and transportation.

And to make it even worse, it doesn’t burn up completely and ends up producing CO2 and carbon monoxide.8,24

Energy Production

Again, ethanol carries the day when it comes to this round because when you compare the two, it is the one that produces a lower amount of energy. Gasoline, however, is infamous for producing more energy, that is in comparison to a single gallon of ethanol.

The rate is at least 30% or a third higher.

Engine Damage

It is not all bad when it comes to gasoline because it one-ups ethanol in this aspect. Auto experts are often concerned about how ethanol has the potential to damage the engine.

It has some downsides: being more corrosive, hygroscopic, and increasing oxidation levels in the tank.

Gasoline wins in this round because it has been in use for the longest time, and there have never ever been any issues with it corroding or affecting the engine or system parts in any way. It can be hailed as the option that is safer for the vehicle because it will never interfere with its performance.

Ethanol Carbon Capture: The Role of Ethanol in Preventing Climate Change

Undeniably, climate change has been the single most impactful long-term effect on the planet that has been mostly caused by human activities.

As earlier stated, almost everything you do has an impact on the environment, be it your household, transportation option, or economic activity. One factor that cannot ever be ignored is fuel use.

Have you ever for once wondered why there is a sudden increase in the number of electric bikes and vehicles on the roads? Well, that is because fuel is one of the main causes of climate change, fossil fuels, to be exact.

Following the report by the World Nuclear Association,25 imagine about 36 bt of carbon is released into the air every single year no thanks to the burning of these fossil fuels.

Source Percentage emissions
Coal 45%
Oil 35%
Gas 20%

So, what happens is this. You see the carbon that is emitted, it finds its way into the air, and there is a reaction with oxygen, leading to the formation of CO2 of course that creates a heating blanket in the atmosphere and that in turn causes the earth to warm up.

Thankfully, biomass and ethanol, in this case, help by a great deal, to reduce the carbon levels in the air and go ahead to aid in climate justice efforts.

It is excellent news that the life-cycle emissions of biomass are relatively lower, and it is easy to see why.5

Electricity source Life cycle emissions (g CO2 per kWh)
Coal 820
Natural gas 490
Biomass 230
Solar (roof) 41
Geothermal 38
hydropower 24
Nuclear 12
Wind 12

There is quite a lot that this reduction of carbon levels in the air has done for the planet, it has gone a really long way to help. The impact may not be clearly seen instantly, of course, but you know that the fight for climate justice takes some time for the results to show.

All these only go to show that using alternative fuel sources like biomass and reducing the overreliance on fossil fuels does a great deal for the planet.

A graphic that shows the different uses of ethanol such as for beauty products, antiseptic products, solvents, additives, alcohol manufacture, and fuel.

When people are able to turn to more sustainable options and completely avoid harmful fossil fuels, there is a lot of reduced pressure on the manufacturers to keep mining. The less they have to mine, the better it gets for the planet, because it is the single activity that is infamous the world over for having one of the highest rates of emissions.

The lower the demand is, the better it becomes for environmentally-friendly options, and that is exactly what the production of ethanol does.

Backing up ethanol manufacture with other effective remedies goes a long way to help the planet heal.26 For instance, the use of solar and wind power also goes a long way to help reduce the overreliance on fossil fuels.

However, perhaps the most important way that the planet gets back on its feet is if there is more emphasis on tree planting. The carbon sequestration properties of trees make them one of the most effective remedies that help reduce the impact of climate change.

Environmental Effects of Using Ethanol

When it comes to the very important subject matter of climate change and the topic of using ethanol as a fuel substitute, it is very crucial to discuss both the positive and the negative effects that it has on the environment.


  • Instrumental in climate justice efforts: Research has it that ethanol has been of great help in reducing the amount of emissions that are caused by the transport sector. Unlike pure gasoline, it has proven to be the cleaner and more sustainable option because there are reduced fumes emissions.7
    In 2020, there was a record that using ethanol reduces carbon emissions by as much as 47.3 million metric tons, which is a huge deal if you get to think about it. To put it in perspective, it is kind of the same as getting a whopping 10 million cars off the roads for an entire year or, better yet, the same as eliminating 12 coal power factories for a year.
  • Improvement in air quality: One of the major complaints from people living in air-polluted regions is that the air quality is terrible. You can tell by how they wear masks to at least reduce the prevalence of respiratory diseases and other complications.
    Thankfully, more usage of ethanol is slowly striving to change that.
    A great example is how the mandate of blending ethanol with gasoline has led to a reduction in tailpipe emissions. There is less pollution from carbon and other toxins in the air, like benzene.
    Otherwise, these would have reduced the oxygen intake into the body and increased the risks of cancer and causing severe birth and reproductive health complications.
  • Increased land productivity: This doesn’t necessarily mean that the increased demand for corn has led to more land being plowed, as many opposing groups claim. What this technically means is that the same lands that were used to provide a certain amount of corn have now increased their production level.
    The land size is still the same, only that more technology has improved production.1


  • It sometimes leads to deforestation: The planting of crops for the production of ethanol doesn’t have a negative impact on the environment but the problem comes in when it means the clearing of massive acres to find space for the farming of the crops. If the production must involve deforestation, then that makes ethanol harmful to the environment.

Trees are the ones that fight climate change and keep the air cleaner while canceling the effects of the release of harmful gasses,27 and cutting them down only for growing crops for ethanol production is devastating to the environment.

Ethanol Pros and Cons

Apart from having an impact on the environment, ethanol also has a role to play when it comes to other aspects of daily living.

The following are other ups and downsides of ethanol that you should definitely be aware of.


  • It is more cost-effective: The thing about ethanol is that you can find it virtually anywhere because anyone is able to produce it, just as long as they have landscape and any country can be a supplier. Considering that it comes from food crops like corn and cane that can grow almost anywhere, ethanol is one of the most readily available fuel sources.
    Gasoline and other fossil fuels are more expensive. Not every country has the financial or technological capability to extract or process it, which makes it play against many economies, especially those that are in the third world.
    The mining process is pretty high cost and that kind of explains why gas is more expensive to consumers.
  • Easy accessibility: There is literally no way that a country would state that they are not able to produce ethanol fuel. All it needs is the growing of some crops, which is already going on in massive land parcels in almost every country.
    This means that this fuel source may be one of the easiest to find. Besides, corn and grains and staple foods in most countries, including the third world.
  • Less dependence on non-renewable energy sources: Experts the world over will agree on this. And that is the fact that one of the very first steps to help reduce climate change is to lower the dependence that people have got on fossil fuels.
    Households don’t seem to stop over-reliance on grid power and people tend to go for pure gasoline cars and that literally means that fossil fuels will still be in high demand, leading to more mining and production, which is rather harmful to the environment.
    One of the best and maybe the only way to ease this pressure is by tapping into the potential that renewable energy sources like biomass have got. They are more economical and definitely friendlier to the environment, and it doesn’t harm that they are not heavy carbon emitters.
    Besides, the money that is saved in producing ethanol instead of gasoline can be of really great benefit to a country and can be able to go to other sectors of the economy.
  • Employment opportunities: One of the several benefits of ethanol production is that it has led to the creation of so many job opportunities. In 2019 alone, there were an impressive 68 000 jobs created in the US alone, and that doesn’t account for the hundreds of thousands of people employed in various parts of the world like China and Brazil.
    The more plantations grow in various parts of the world, the more job opportunities are created because manpower is needed in these farms, not to talk of the processing plants. Apart from producing fuel, ethanol can also be used to make alcoholic beverages, meaning more opportunities for employment for the people.9


  • Land requirement: Ethanol production also has some downsides and one of them is the fact that it means the usage of large parcels of land to meet the raw material demand. Only large-scale production makes sense in order to produce the required amount of ethanol, and there are warranted concerns about what that means to the environment as well in terms of land clearing and usage of high amounts of fertilizers.
  • Increase in food prices: The main raw material for ethanol production is corn. What does that mean to the agricultural sector?
    That the demand for corn will increase, and that has a rippling effect on the consumer because that would mean an increase in prices. There is also another downside to it because while more emphasis is being made on the utilization of corn as a fuel source, what about corn for animal feed?
  • Hygroscopic nature of ethanol: Ethanol is heavily attracted to water, and the two are miscible. It can easily absorb any water present around it and even from the air.
    This is a huge challenge in the automotive world because the gasoline and ethanol blend will always have water content, and gas can never be in its most pure form. This causes engine and overall performance issues.

How Ethanol Corn Emissions Can Be Reduced?

The shocking fact about ethanol production and use is that it is not and maybe never will be carbon neutral.

It is true that it is better for the environment than other fuel sources like gasoline, but it still has a few negative effects on the ecosystem, and they also have to be addressed to make it more eco-friendly than it already is.

Pie graph that shows the percentage of fossil fuel emissions led by coal, then oil, and then gas.

The efforts to reduce the carbon footprint of ethanol should start at the farmers’ level since that is the beginning of the life cycle of emissions. Sensitizing them about the environmental impact of their activities can go a long way to help reduce their carbon footprint.

It can start with their choice of fertilizers, how much land size they use, and many other aspects.

They can also be encouraged to opt for renewable energy sources for water pumping, running farming equipment, and all other activities on the farm.3 The manufacturing process of ethanol is also a huge contributing factor to carbon emissions.

As a matter of fact, it is one of the aspects that makes environmentalists fault the entire concept of using ethanol as a substitute.

They make a lot of sense because the process of distillation and fermentation is a bit lengthy and there is a lot of heat required. It is a menace to ethanol’s GHG balance because many plants use fossil fuels to power the process, which leads to more carbon emissions that affect the environment.

That also beats the entire purpose of producing ethanol as a clean energy source because it will still, at the end of the day, involve the use of fossil fuels.

The next culprit that increases the carbon footprint of ethanol is transportation to its final destination after manufacturing. Given that it was one of the country’s largest exports, it traveled great distances to reach countries like Brazil, Canada, and China, and you know that the transport sector is another heavy carbon emitter.

While using it locally is a bit friendlier to the environment, there is still a huge problem when it comes to ethanol exportation because it has to travel thousands of miles before it is consumed. Maybe if there was more emphasis on local use, the emissions would significantly reduce, but that is obviously going to hurt the economy.

What Is the Future of Ethanol and Other Biofuels?

Ethanol and other biofuels have so far proven that they deserve a place in the modern world. Time and again they have shown that they are way cleaner alternatives to fossil fuels which are non-renewable and have devastating effects on the environment, especially in the long run the more they are in use.

With a source like ethanol, you don’t have to worry about land, air, and water pollution caused by the extraction, like what happens during the mining process of fossil fuels. Being renewable means that the supply does not run out, and it helps that power from biomass is relatively cheaper compared to gasoline.

Given the fact that biofuels have so many upsides to them, you can’t help but wonder, are they lasting solutions? What does the future have in store for them?

Apart from the combative efforts from lobby groups, the EPA is pretty confident about the place of biofuels in the current world. The world is slowly turning to renewable energy, and biofuels are here to stay.

The only challenge is to deal with the pressing concerns about the environmental impact of the distillation process, but once that is taken care of, ethanol will be one of the top fuel sources for powering vehicles.

The government is doing quite a lot to make sure that it is more environmentally friendly, and the good thing is that there are measures already in place. For instance, there is already an urgent push for more sustainable low-carbon agricultural practices, and farmers are being encouraged to make use of renewable sources of power for all their farming processes and any other activities to do with corn production.

Furthermore, the development of more efficient distillation processes is also in the works to help sort of reduce the carbon footprint of the entire refining process. Therefore, these efforts only go a long way to show that there is a lot of faith in corn ethanol as a power source.

That also does a lot to explain why the E85 is gaining more and more popularity in the automotive world.

You should know that there are certainly several upsides to using ethanol as an alternative fuel source. Not only is it readily available and cheaper to acquire, but it is also better for the environment in comparison to other non-renewable sources.

And that is why governments can’t help but advocate for its use and keep on funding research and production.

What’s more is the fact that ethanol has also reduced GHG emissions from the transport sector, even though it also has a few obstacles to overcome. For example, there are concerns from a lot of people that it uses up a lot of land and sometimes sory of contributes to deforestation.

And apart from that the distillation process is also infamous for being a heavy emitter.

Such reasons are some of the hurdles that the industry has to overcome in order to make the power source a little more sustainable.

But still, all in all, regardless of the downsides, it doesn’t take away from the fact that it is a crucial part of the modern world and has a place in the transport sector; this is all thanks to the low carbon footprint of ethanol and its several other upsides.

Frequently Asked Questions About Carbon Footprint of Ethanol

What Is the Carbon Footprint of Ethanol Gas?

The best part about using ethanol gas is the fact that it has a low carbon footprint and is way better for the environment than other fuel sources like gasoline and other fossil fuels. The numbers show that when you burn a gallon of ethanol (E10), its entire life cycle emission stands at about 8,595g while driving for a single mile with (E85) leads to about 315g of carbon, which is a lot lower than the emissions caused by fossil fuels.


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