The Pros and Cons of Ethanol Fuel

Farm producing ethanol with field and machinery.

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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.

Advantages of Using Ethanol as a Fuel

Better for the Environment

Overall, ethanol is considered to be better for the environment than traditional gasoline. For example, ethanol-fueled vehicles produce lower carbon dioxide emissions.

E85, ethanol-gasoline blends that contain 51% to 83% ethanol, also has fewer volatile components than gasoline, which means fewer gas emissions from evaporation. Adding ethanol to gasoline even in low percentages, such as 10% ethanol and 90% gasoline (E10), reduces carbon monoxide emissions from the gasoline and improves fuel octane.

Because it is mostly a product of processed corn, ethanol also reduces the pressure to drill in environmentally sensitive places, such as the north slope of Alaska, the Arctic Ocean, and the Gulf of Mexico. It can replace the necessity for environmentally sensitive shale oil—like that coming from the Bakken Shale—and reduces the need for the construction of new pipelines like the Dakota Access Pipeline.

Creates Domestic Jobs

Ethanol production also supports farmers and creates domestic jobs. And because ethanol is produced domestically—from domestically grown crops—it reduces U.S. dependence on foreign oil and increases the nation’s energy independence.

The Drawbacks of Ethanol Fuel

Different Environmental Impact

Though ethanol and other biofuels are often promoted as clean, low-cost alternatives to gasoline, industrial corn and soy farming still have 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. In general, corn production is a frequent source of nutrient and sediment pollution.

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

Need for Land

Another debate about corn and soy-based biofuels concerns the amount of land it takes 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. 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—a sacrifice few people would be willing to make.

“Replacing only five percent of the nation’s diesel consumption with biodiesel would require diverting approximately 60 percent of today’s soy crops to biodiesel production,” says Matthew Brown in a paper presented at the Conference on Aviation and International Fuels. Brown is an energy consultant and former energy program director at the National Conference of State Legislatures.


Also, when considering the implementation of ethanol, it must be noted that biofuels aren't meant for all vehicles, especially older ones.

One solution to this has been the introduction of flexible fuel vehicles. These have the advantage of being able to use E85, gasoline, or a combination of the two and give drivers the flexibility to choose the fuel that is most available or best suited to their needs.

Still, there is some resistance from the automotive industry when it comes to adding biofuels like ethanol to the market.

View Article Sources
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  6. Pimentel, David, and Tad W. Patzek. “Ethanol Production Using Corn, Switchgrass, and Wood; Biodiesel Production Using Soybean and Sunflower.” Nat Resour Res, vol. 14,, 2005, pp. 65–76., doi:10.1007/s11053-005-4679-8

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