What is e85 gas?

If you own or choose to own an e85 ethanol flex-fuel vehicle (FFV), there are some cool points you will be pleased to know as well as compromises you will have to make in your driving habits.

Approximately, the price of e85 gas is 30% less than that of gasoline. This is why many motorists prefer it, especially in Brazil. In the United States, regardless of few cars owners with FFVs, e85 gas is quickly gaining favor. So, what is e85 gas?

What does e85 gasoline mean?

E85 gasoline, also known as flex fuel, refers to a fuel blend that holds up to 85% of ethanol and 15% of gas, thus giving us the e85 derivative.

Ethanol is a bio-fuel obtained from biomass sources such as ‘starchy’ wastes, grains, and corn crops in the U.S. and wheat, sorbent, and sugarcane in Australia and Brazil. This natural, non-toxic alcohol burns cleanly, reducing greenhouse emissions by about 59%. Ethanol is manufactured in rural farming areas across America.

e85 gasoline

Flexible Fuel Vehicles (FFVs) are cars designed to specifically run on a particular blend of Ethanol and unleaded gasoline. While most fuels contain some percentage of ethanol in them, only flexible fuel vehicles can run on the e85 blend.

What is e85 gas? – Is it regular gas?

E85 fuel is a high-performance fuel with a higher octane rating than regular gas. When referring to octane ratings, we refer to the volatility in gasoline. High octane ratings represent least volatile gas, and best suited for performance gas-engines, requiring high compression ratios when the engine converts fuel into movement.

Ethanol’s high octane rating enables it to run with more boost and a higher compression ratio, while still maintaining immunity from detonation. Furthermore, cars that run on e85 gas produce fewer emissions than those using regular gas.

Regular gasoline has an octane rating ranging between 87%-94% and is more costly as compared to e85 gas. It is manufactured from fossil fuels as well as some detergents and additives to increase performance. Consequently, e85 gas is not regular gas, since it is from ethanol and gasoline blends.

E85 vs. Gasoline

When filling up your vehicle at a gas station, you may be wondering whether you are using the best fuel for your engine. According to the U.S. Energy Information Administration, there are more than 10.6 million flex-fuel vehicles, with many owners not realizing their engines can run on e85 gas. Using e85 gas has its advantages and disadvantages. Some of them include:

Pros of ethanol in gas

Made from renewable organic sources

Environmentally friendly

E85 gas contains 85% of ethanol and 15% of gasoline. Ethanol is a renewable source of energy that is harvested in rural farms all across America, mainly from corn. With an unlimited supply of corn, we can manufacture American-made fuel that is better for your engine’s condition than gasoline.

Regular gas is from fossil fuels, whose consumption has increased in the last 200 years, leading to depleted fossil fuel reserves. With the increased need for fuel, relying only on fossil fuels to produce gasoline could put the world’s fuel economy at risk.

Environmentally friendly

E85 gas burns cleaner than regular gasoline, emitting no carbon dioxide into the air. The high amount of oxygen in its chemical structure allows it to burn pretty cleanly. This reduces the emission of greenhouse gases like nitrogen oxides and carbon monoxide.  Carbon dioxide is one of the significant causes of climate change and global warming.

Cheaper than regular gas

The cost of e85 gas in miles per gallon is less expensive than that of gasoline due to the lower energy content per unit volume in the ethanol in e85 gas. In turn, it may require increased fuel flow in flex-fuel engines. Luckily, e85 gas is a lot cheaper than standard gasoline.

Cons of ethanol in gas

Not suitable for all car models

Not suitable for all car models

When used in incompatible engines, such as those of vehicles made before 2008, e85 gasoline may corrode the fuel-system components, rubber, magnesium, and aluminum. For e85 gas to run efficiently in older engines, it is vital to tune it up. Make replacements on the fuel hoses, fuel pumps, seals, gaskets, throttle bodies, fuel injectors, and fuel filters, among many others.

Some recent car models can run with ethanol gas in their engines up to a certain point.  Flex fuel vehicle are made to run with any ethanol-gasoline blend up to e85 gasoline. Consult your owner’s manual or vehicle’s warranty to clarify if your vehicle can efficiently run on ethanol blends.

Increased fuel consumption

Regular gasoline produces more energy than ethanol blends. The engine of a typical vehicle burns 20%-30% more e85 gas than it would regular gas. Vehicles using e85 gas are bound to increase fuel flow, thus a higher fuel economy for FFV owners.

More so, flex fuel stations are fewer than regular gas stations. In case of an emergency, it is likely that if your FFV runs out of gas, the next flex fuel station could be miles away from you.


Although the discussions about e85 gas vs. regular gasoline are endless, it is clear that ethanol is receiving favor with many in powerful positions. There are more ethanol refining plants, and ethanol is well on its way to becoming the first alternative source of fuel with extensive public use.

However, it is advisable to consider what is e85 gas carefully, and if your vehicle is ethanol compatible, to avoid engine explosions and severe accidents.

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