Flex-fuel vehicles (FFVs) are designed to run on more than one type of fuel, typically a combination of gasoline and ethanol. Ethanol is a renewable fuel made from plant materials, which can help reduce greenhouse gas emissions. FFVs can use any blend of these fuels, allowing drivers to choose the most cost-effective or environmentally friendly option available. These vehicles are equipped with special engines and fuel systems that can adjust to different fuel types. Commonly, FFVs can operate on up to 85% ethanol, known as E85, or regular gasoline. This flexibility provides consumers with more choices at the pump and supports the use of alternative fuels.