E85 ethanol fuel costs less per gallon than regular gasoline, but the math gets complicated once fuel economy drops into the equation. Jalopnik ran the numbers to determine whether the switch actually saves drivers money despite lower mileage.
E85 contains 85 percent ethanol and 15 percent gasoline. Most flex-fuel vehicles see a 20 to 30 percent reduction in fuel economy when running E85 compared to regular 87-octane gasoline. That efficiency penalty stems from ethanol's lower energy content relative to gasoline.
The real question becomes whether E85's lower pump price offsets the mileage loss. If E85 costs $1.50 per gallon versus $3.50 for regular gasoline, the math looks appealing at first glance. But if your vehicle achieves 25 mpg on gasoline and only 18 mpg on E85, the cost per mile climbs significantly.
Using typical pricing and efficiency numbers, E85 often fails to deliver meaningful savings once the mileage penalty factors in. In many cases, drivers spend the same amount or slightly more per mile. Regional fuel availability also matters. E85 remains sparse in rural areas, limiting convenience for many owners.
Automakers including General Motors, Ford, and Chevrolet offer flex-fuel engines in trucks, SUVs, and performance cars. These powerplants run optimally on either fuel type. However, engine tuning matters. Some vehicles tolerate E85 better than others, with performance variants sometimes seeing smaller economy penalties.
The fuel choice makes the most sense for drivers who refuel frequently at convenient E85 stations and who run the numbers for their specific vehicle and regional pricing. Price-conscious buyers in areas with robust E85 infrastructure might find small savings. Everyone else should stick with regular gasoline.