(WHTM) – Gas prices are at an eight-month high right now and you may be curious about a cheaper option called “flex fuel.”

As gas prices move back up to $4 a gallon, $5 in California, drivers are once again checking out a cheaper option, ethanol-based gas.

Vince Ward said, “Looks like it’s 30 cents cheaper on the gallon!”

Ward was interested.

E85, made primarily with corn alcohol was selling for $3.23 instead of $3.53 for regular, and $4.03 for midgrade.

More fuel centers than ever are now offering ethanol-based gas, either E85 or E15.

So what’s the difference between these blends and regular 87 gas?

It’s confusing, so we checked with the Department of Energy to find out the difference.

87 Octane Regular typically contains 10% ethanol it’s fine for all vehicles.

E15 gas contains more ethanol, around 15%, the Biden Administration has been pushing to cut our dependence on expensive oil.

President Joe Biden said, “With this waiver on June 1, you’re not gonna show up at local gas station and see a bag over the pump that has the cheapest gas. You’re gonna be able to keep filling up with E15 and it’s gonna solve a whole problem.”

But the strongest ethanol blend is E85.

E85 contains 85% ethanol, but it’s only for flex-fuel vehicles that say “flex-fuel” allowed, and typically have a yellow fuel cap.

Ward, tired of rising prices, is going to check it out.

“I’m gonna go ahead and research it myself and see if it is any better than the regular,” said Ward.

Yes, E85 is cheaper, but there’s a catch.

The EPA says most vehicles see a 15 to 20 percent mileage reduction with E85.

So E5 needs to cost 20% less than gas to save money.

If you aren’t sure if this gas is safe for your car, check with your dealer’s service department or mechanic.

They’ll give you an honest opinion so you don’t waste your money.