As congress debates year-round access to E15 gasoline, Purdue University mechanical engineering professor Greg Shaver says it’s safe for most passenger vehicles manufactured in 2001 or later.

“There should be no concern whatsoever using E15 in your car or your passenger truck or SUV, as long as it's 2001 or newer,” Shaver said. “For vehicles that are older than that, 2000 or earlier, they should use another option at the pump.”

Shaver said E15, which appears as UNL88, should not be used for boats or small engines, such as in lawn mowers and weed eaters, unless indicated by the manufacturer.

E15 is a fuel blend that contains 15% ethanol and 85% gasoline. It has received increased attention in recent years as federal administrations have issued waivers allowing the fuel to be sold during the summer.

Most gasoline sold in the United States contains 10% ethanol, Shaver said. E15 contains up to 50% more ethanol than conventional E10 gasoline.

"The main benefit of E15 is that it can reduce the amount of cost at the gas station," Shaver said.

Growth Energy reported E15 saves drivers up to 30 cents per gallon compared to E10 gasoline.

Shaver added that ethanol production is beneficial for American farmers.

“Approximately half the corn that is grown in the United States today is used to make ethanol,” he said.

In January 2025, President Donald Trump issued an executive order directing the Environmental Protection Agency to consider emergency fuel waivers that would allow year-round sales of E15 in case of gasoline shortages.

In May 2026, the U.S. House of Representatives approved legislation that would permanently allow year-round sales of E15 nationwide. The bill is waiting to be heard in the Senate.

“You can always choose not to use E15,” Shaver said. “You can use E10 or something else, right? I think that's really what's exciting about the opportunity to use E15, is that people can make a decision to use the fuel that meets their needs.”