E15 Won't Save You Much, But Washington And Corn Farmers Will Probably Push It Anyway

The Biden administration is reportedly considering lifting a summer ban on gasoline with higher ethanol content for very slim savings at the pump.

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You might see higher-ethanol blends of gasoline at the pump this spring and summer. The federal government may remove restrictions on E15 fuel — gasoline with 15 percent ethanol content, as opposed to the more common 10 percent — as a way of curtailing rising gas prices, per Reuters.

Typically, E15 gas isn’t offered between June and September because it breaks the EPA’s limits on Reid vapor pressure, and fuels with higher RVP levels more readily contribute to smog in warmer weather. However, the corn lobby is a weirdly strong one in this country, and lawmakers from states known for producing the crop are seemingly seizing the current geopolitical climate to nudge E15 back into gas stations year-round. From Reuters:

A bipartisan group of U.S. Farm Belt lawmakers has been pushing the White House to lift the summertime ban.

Earlier this month, senators including Chuck Grassley from Iowa and Dick Durbin from Illinois - the two biggest corn-producing states - asked Biden in a letter that he allow the sale of E15 over the 2022 driving season, arguing the added ethanol would deliver lower costs to consumers.


But how much cheaper would E15 gas be versus E10? We’ve been here before — in fact, the last time gas prices peaked. Ethanol is cheaper by the gallon but less energy dense than gasoline. Compared to E10 fuel, which is pretty much ubiquitous, E15 might only save about five cents. Here’s how Edmunds broke it down almost a decade ago, the last time the corn lobby was pushing year-round E15 hard:

It might actually be more of a wash than a win. Given the disparity in energy density, E15 would deliver about 5 percent less fuel economy than gasoline, versus a 3.5 percent decline compared to everyday E10 fuel. Efficiency for a specific vehicle would depend on terrain, temperature, vehicle type and load, the way the engine is tuned and the manner in which the vehicle is driven.

On the cost side of the equation, if an E10 blend of fuel were selling at $4 a gallon, an E15 blend would be about $3.95. This would represent a savings of just 1.3 percent. Over 10,000 miles, the driver whose car gets 27 mpg using $4-a-gallon E10 would buy 370 gallons of fuel, at a cost of $1,480.


That’s the other side of the equation — even though E15 is a little cheaper at the pump, you end up buying a little more of it in the long run, because your car won’t go quite as far on a tank of the stuff.

Speaking of, “your car” in this scenario is a key concern. In 2012, the EPA approved E15 fuel for all vehicles model year 2001 and newer. Car manufacturers and AAA, of all entities, contested that blanket recommendation:

The American Petroleum Institute says a three-year study conducted by automakers and the oil industry found that E15 is a consumer safety issue for a majority of drivers with pre-2012 vehicles. “Our testing of a range of ethanol levels at 15% to 20% has identified issues about engine durability,’’ API group director and engineer Bob Greco says.

Congressman Jim Sensenbrenner has proposed legislation requiring the EPA to authorize an unbiased study of E15, agrees with the AAA. “(The) findings affirm what we have already heard—E15 causes premature engine damage and voids warranties, even on new models,” the Wisconsin Republican says. “Concerns about E15 are not diminishing, they are increasing. That is telling. When an organization like AAA, a nationally trusted source for motorists, calls out the EPA, you would think the (Obama) Administration would listen.”


E15 should be safe for most newer cars at this point, but probably isn’t a great idea to use with any 20th-century motors. It’s definitely not a good idea to fill up on E15 with a smaller engine, like a two-stroke, because of the way they throw oil into the fuel-air mixture. Ethanol absorbs water, oil’s best friend. Or is it natural enemy? Whatever — it’s probably not important.

Reuters also points out that a higher concentration of ethanol in fuel will likely raise corn prices, all for a negligible difference in how much you spend to top off your car over the long term. So this potential government initiative has all the makings of a grand political gesture with little benefit to anyone, except those responsible for making the crop in question. Guess we just could have skipped to that part.