The Ministry of Road Transport and Highways has notified amendments to the Central Motor Vehicles Rules, 1989, to facilitate the adoption of flex-fuel vehicles capable of running on high-ethanol blends such as E85 and E100.The amendments update emission certification provisions by explicitly including E100 alongside E85. Vehicles certified to operate on these fuels will have to comply with the emission and safety requirements applicable to their respective categories, an official statement said on Monday.E85 is a blend of petrol and ethanol containing up to 85 per cent ethanol by volume, while E100 refers to fuel consisting predominantly of ethanol. Flex-fuel vehicles are specially designed to operate on different petrol-ethanol blends using a single fuel tank, with engine management systems automatically adjusting to the fuel composition.The technology is already in use in countries such as Brazil and the United States. Depending on their design and certification, flex-fuel vehicles can operate on a range of fuel blends, including E85 and E100. Their fuel system components and materials are designed to withstand the approved blends, allowing motorists to choose from the fuel options specified by the manufacturer.The increased use of domestically produced ethanol is expected to help reduce India’s dependence on imported crude oil. Ethanol use in appropriately designed vehicles can also reduce certain exhaust pollutants and lower greenhouse gas emissions over the fuel’s lifecycle, depending on the feedstock and production process.The ministry has clarified that E85 and E100 fuels are intended exclusively for vehicles specifically designed and certified to use them. The provision will not apply to conventional vehicles currently available in the market or already in use. Compatibility with E10 or E20 fuel does not automatically make a vehicle suitable for E85 or E100.The notification does not require existing vehicle owners to switch to high-ethanol fuels or modify their vehicles, either now or in the future. Motorists have been advised to check their vehicles’ fuel compatibility stickers and consult the manufacturer’s instructions in the owner’s manual before selecting a fuel at a filling station.The amendments also update provisions relating to biodiesel and incorporate certain technical corrections. The revised rules will come into force from the date of their publication in the Official Gazette.