Corn growers and policymakers eager to blend greater amounts of ethanol into U.S. gasoline supplies may have just achieved a significant goal.

Fiat Chrysler Automobiles (FCA) recently approved E15 fuel for use in all of its 2016 models, making it the last of the Detroit Three automakers to do so.

E15 is a blend of 15 percent ethanol and 85 percent gasoline, meaning it has more ethanol than the E10 that's already sold at most gas stations.

DON'T MISS: Final 2016 Ethanol Rule: Fuel Blenders, Biofuels Interests Unhappy With EPA Numbers (Dec 2015)

FCA's acquiescence means the majority of new vehicles sold in the U.S. are now approved for E15 fuel, according to Reuters.

New FCA vehicles are now able to run on E15 without modifications, just as they have been on E10 for more than two decades.

That's distinct from the handful of "flex-fuel" vehicles specially equipped to run on E85—85 percent ethanol—as well as regular E10 gasoline.

2015 Dodge Durango

2015 Dodge Durango

Back in 2012, the U.S. Environmental Protection Agency nominally approved E15 for all vehicles built in 2001 or later, but that was not an opinion shared by all carmakers.

E15 has met significant resistance from auto-industry trade groups and even AAA, because of concerns that it can damage fuel-system components.

At the same time, corn growers have pushed for greater amounts of ethanol to be blended with gasoline, a move that also helps meet numeric alternative-fuel goals specified in the 2007 Energy Independence and Security Act.

ALSO SEE: Automaker Group Says E15 Ethanol Damages Cars, EPA Approval Was Rushed (Nov 2013)

Intended to help cut both emissions and the country's dependence on foreign oil, the act established a Renewable Fuels Standard that mandated fixed amounts of ethanol be introduced to the fuel supply.

But lawmakers didn't account for reductions in overall fuel consumption that have resulted from increases in overall fuel efficiency, rather than the steady increase in gasoline use expected when the law was written.

And consumer interest in E15 has been tepid at best.

2016 Jeep Cherokee

2016 Jeep Cherokee

Few gas stations have thus far been willing to invest in the "blender pumps" that are required to add greater amounts of ethanol to gasoline.

Of more than 100,000 gas stations in the U.S., only a handful are estimated to offer E15.

So while the number of cars on U.S. roads that can safely run on E15 is growing, the number of drivers actually filling up with it likely isn't.

MORE: State Laws On Ethanol In Gasoline: Only Seven States Require E10 Blend (Jul 2015)

Ethanol boosters hope that having more E15-compatible cars on the road will convince more station owners to invest in "blender pumps."

But it's a chicken-and-egg situation: That will only make sense for station owners if more customers start asking to fill their tanks with E15.

Ethanol contains less energy than gasoline, and with today's low gas prices, it's likely not the most appealing option financially.

2016 Fiat 500L

2016 Fiat 500L

Various analyses have also questioned the benefits of turning over large tracts of land to ethanol production, and whether ethanol can be produced in large enough quantities to reduce gasoline consumption significantly.

And while FCA represents over 10 percent of the U.S. new-car market, some automakers still haven't approved E15 for use in their new cars.

Nissan and Mercedes-Benz are among the holdouts, and reportedly have no plans to change their positions.


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