The Ministry of Road Transport and Highways (MoRTH) has notified amendments to the Central Motor Vehicles Rules, adding E100 as an approved fuel option alongside E85 for flex-fuel vehicles. E100 refers to 100 per cent ethanol-based fuel. The ministry has changed certain vehicle classification thresholds, fuel specifications, and technical references used in emission-related tables and testing provisions. Additionally, the Government has raised the vehicle weight limit to 3,500 kg from the previous threshold of 3,000 kg for light petrol and diesel vehicles affected by these changes.
The notification, issued on October 23 and published in the official gazette on October 26, comes into immediate effect. This follows draft rules published on April 27, after which the ministry reviewed public objections and suggestions before issuing the final notification. According to the notification, vehicles designed and certified for high-ethanol blends can use E85 and E100 fuels. Vehicles that use E20 or normal fuel can’t use E85 or E100 fuel.
A senior road transport ministry official said fuel beyond E20 and up to E100 is intended only for vehicles designed and certified to use it and will not be applicable for other vehicles.
Transitioning to E100 or high-ethanol blends requires significant vehicle reconfiguration: fuel system components - seals, fuel lines, injectors - must be upgraded to handle ethanol’s corrosive properties, and engine management systems need retuning for ethanol’s different combustion characteristics.
Flex-fuel vehicles are designed to run on any mixture of ethanol and petrol, from pure petrol to E100, with onboard sensors adjusting engine parameters accordingly. Brazil currently operates the world’s most mature flex-fuel programme since 2003, where sugarcane-derived ethanol powers a large share of the vehicle fleet - though users typically have a choice to buy petrol with lower ethanol content.
In June this year, Maruti Suzuki India launched India’s first flex-fuel passenger vehicle, introducing Wagon R Flex Fuel capable of running on ethanol-petrol blends from E20 to E100.
The Government has been promoting ethanol-blended petrol as part of its strategy to reduce dependence on imported crude oil, one of the biggest contributors to its current account deficit.
Major automakers, including Toyota Motor Corporation, Tata Motors, and Hyundai Motor Company, are also developing flex-fuel vehicles for the Indian market as policymakers push to reduce the country’s fossil fuel import bill.
In the current scenario, when the West Asia conflict has left many countries, including India, vulnerable to the energy crisis, flex-fuel vehicles assume all the more importance.