10 Environmental Impacts of Ethanol

Ethanol is a sustainable, domestically generated fuel with a higher octane rating than gasoline, allowing it to perform better than gasoline. However, there are some environmental impacts of ethanol production and consumption that have been discovered, and we are going to discuss them in this article.

Ethanol is a bio-organic fuel that may be used to replace fossil fuels in transportation. It has a great potential to contribute to the decarbonization of transportation and improve environmental performance.

The current research may be extended in the future to high-speed SI engines to improve performance and combustion characteristics by doping nano-particles with gasoline. The numerical analysis may be performed on a SI engine that is powered by another alternative energy source to improve performance characteristics.

Additionally, this study may be improved by including exhaust gas recirculation to help reduce NOX emissions and by modifying it to operate in dual-fuel mode.

Ethanol is a relatively low-cost alternative fuel that boasts less pollution and more availability than unblended gasoline. But while there are many advantages of using ethanol as a fuel, there are some drawbacks as well.

What is Ethanol?

Ethanol is a grain alcohol that can be blended with gasoline and used in motor vehicles. Many gasoline stations provide a blended fuel, which is typically 10 percent ethanol and 90 percent gasoline.

Ethanol can be fermented from many sources of starch, including corn, wheat, grain sorghum, barley, and potatoes, and from sugar crops such as sugar cane and sweet sorghum.

A by-product of ethanol production is distiller grains, which can be fed to livestock either wet or dried. Because the wet distillers grains are perishable and heavy, which adds to transportation costs, they are usually used within a 100 mile radius of an ethanol plant.

Distillers grains are more stable and easier to transport when an ethanol producer dries them, however that increases the energy cost for the ethanol producer. Distiller grains retain many of the nutrients from corn, since only the starch has been removed.

How is Ethanol Produced?

Ethanol is produced with plants known as “dry grind” plants, the corn kernels are finely ground into small particles. Then water is added to the ground corn along with enzymes to convert the starch for fermentation. The mixture, also known as mash, is cooked to break the starch down further.

The mash is removed from the cookers and allowed to cool before a second enzyme (glucoamalyse) is added to the mash. This enzyme helps turn the liquid starch into sugars.

Yeast is added to the mash and the fermentation creates ethanol and carbon dioxide. After about two days, the fermentation process is complete and the mash is heated again.

During the heating process, the ethanol evaporates into a vapor that is collected, while the remaining corn and yeast solids remain.

The ethanol vapor is cooled and condenses into a liquid. This liquid is dehydrated to remove excess water from the ethanol, making “anhydrous” ethanol suitable for blending with gasoline.

Ethanol can also be produced by a wet milling process that separates the corn into several different components and affords many options for end products, including ethanol. This process can be much more complex and exorbitant.

Ethanol is a good fuel for use in spark-ignition engines. It can be used as an additive for diesel (biodiesel). Ethanol is also an important feedstock for the chemical industry.

However, despite its uses, there are some environmental impacts associated with ethanol, its production process and in the process of it’s consumption. Here are the impacts of ethanol on the environment.

10 Environmental Impacts of Ethanol

  • Air pollution
  • Takes a Lot of Environmental Space
  • Human Impact
  • Impact on Agriculture and Food Production
  • Impact on the Soil
  • Global Warming
  • Impact on water
  • Methane (CH4) Generation
  • Impact of on Marine Life.
  • Fire Explosion

1. Air Pollution

Truck and rail transportation are the major modes of moving ethanol to the blending terminals, where ethanol is mixed with gasoline to form the E-10 or E-85 blends for consumer engine use.

Using the more expensive truck, rail and barge transportation increases the rate of gaseous pollutant release in the air, thereby polluting the atmosphere.

However, in a bid to address this issue, currently ethanol is not transported by pipelines that are designed and used for petroleum-based products, but then a few companies are testing shipping ethanol this way.

Also noxious odour maybe produced by the generation of butyrate a metabolite of ethanol biodegradation.

2. Takes a Lot of Environmental Space

One of the basic impacts of ethanol on the environment is that it requires cropland space in which to grow.

Because it is primarily derived from corn, a lot of land space that could be used to grow food or livestock is instead used to grow a fuel product.

3. Human Impact

Acute ingestion of ethanol can cause headaches, nausea, vomiting, drowsiness, fatigue, impaired, judgment, unconsciousness, lack of coordination, and coma.

Inhalation can cause eye and upper respiratory tract irritation, fatigue, and headaches, while dermal contact can cause irritation of the skin, with prolonged contact leading to dry skin, peeling, itching, and cracking.

In addition to heavy alcohol consumption, a byproduct of ethanol may cause addiction and increase all types of injury and trauma. Environmental and genetic factors are involved in susceptibility to alcoholism.

However, moderate ethanol consumption reduces stress and increases feelings of happiness and well-being, and may reduce the risk of coronary heart disease.

Furthermore, malnutrition can be a resultant effect of ethanol and can also exert a direct toxicological effect due to its interference with hepatic metabolism and immunological functions.

A causal effect has been observed between alcohol and various cancers. Cessation of alcohol consumption and balanced nutrition are recommended primary nonspecific therapeutic measures for alcoholics.

Drug therapies for alcoholics, suffering from liver injuries have resulted in mixed results. In end-stage liver disease, liver transplantation may be considered.

4. Impact on Agriculture and Food Production

As stated above, corn and soy-based biofuels concern the amount of land they take away from food production. The challenge of growing enough crops to meet the demands of ethanol and biodiesel production is significant and, some say, insurmountable.

This large portion of land taken for growing ethanol-producing crops only has to a large extent affected food production as agriculture has been the major hit. This has led to a shortage of food supply as the arable land for other crop plantation is used for ethanol crops.

According to some authorities, producing enough biofuels to enable their widespread adoption could mean converting most of the world’s remaining forests and open spaces to farmland, which is a sacrifice few people would be willing to make.

5. Impact on the Soil

In general, corn production is a frequent source of nutrient and sediment pollution. Though ethanol and other biofuels are often promoted as clean, low-cost alternatives to gasoline, industrial corn and soy farming still has a harmful impact on the environment, just in a different way.

This is especially true for industrial corn farmers. Growing corn for ethanol involves large amounts of synthetic fertilizer and herbicide.

Additionally, research addressing the energy needed to grow crops and convert them to biofuels concluded that producing ethanol from corn required 29% more energy than ethanol is capable of generating.

6. Global Warming

When blended with gasoline for use as a vehicle fuel, ethanol can offer some emissions benefits depending on vehicle type, engine calibration, and blend level.

As with conventional fuels, the use and storage of ethanol blends can result in emissions of regulated pollutants, toxic chemicals, and greenhouse gases (GHGs), which are the major cause of global warming.

7. Impact on water

The most significant impacts related to ethanol spills have been on surface water. In some cases, the surface water impact kills aquatic life several days after the spill as a result of the depletion of oxygen.

The impact can occur a long distance from the original site. Also, spills from ethanol can percolate through the soil, thereby leading to possible groundwater contamination and discharge to surface water, which can be a cyclic process as well as methane generation.

8. Methane (CH4) Generation

Anaerobic degradation of ethanol in groundwater results in the production of methane gas. The presence of methane in the unsaturated soil in excess of explosive limits may present an explosion hazard.

Methane gas can be produced over a long period of time and persist in soil gas for a long period of time. And when exposed to the atmosphere, it can lead to the heating up of the earth’s temperature, as methane (CH4) gas has been known to be a greenhouse gas.

9. Impact on Marine Life.

Marine ethanol spills pose a threat of being toxic to ecological receptors in direct contact with the release and could impact the surface aquatic ecosystem.

Oxygen depletion is a major way ethanol affects marine life, as there will not be enough available oxygen for marine life to take in, which with time will result in the lethality of the aquatic life.

10. Fire Explosion

Flammability is the greatest hazard for ethanol, just like it is for gasoline. Especially, when it is exposed to sunlight undiluted. Study shows that ethanol has a wide flammability range of (3.3 to 19% or 33,000 to 190,000 ppm by volume).

Given this concern for flammability, the environment and the lives and properties of humans may be in danger if any form of explosion occurs.

Also, its ability to conduct electricity can lead to electrocution and possibly fire ignition when not properly grounded and bonded during trans-loading operations.


Ethanol, which is one of the most promising biofuels, has attracted attention worldwide due to the looming oil crisis that started over a decade ago around the world. However, for ethanol to be more beneficial to the environment, there is a need for a well-regulated system that includes multiple types of ethanol. This is to protect and preserve the environment.

FAQs – Environmental Impacts of Ethanol

Why is Corn Ethanol bad for the Environment?

Corn ethanol lacks the environmental credentials of other renewable sources of energy such as cellulosic ethanol, wind, and solar energy. As corn ethanol has been discovered to be up to 24% more carbon intensive than even gasoline and thus is proven as a non-climate-friendly fuel


Environmental Consultant at Environment Go! | + posts

Ahamefula Ascension is a Real Estate Consultant, Data Analyst, and Content writer. He is the founder of Hope Ablaze Foundation and a Graduate of Environmental Management in one of the prestigious colleges in the country. He is obsessed with Reading, Research and Writing.

Leave a Reply

Your email address will not be published.