Govt proposes emission rule changes to boost ethanol blends, flex-fuel vehicles

The proposed amendment opens the regulatory door for flex-fuel and pure biofuel vehicles across all categories

The Union ministry of road transport and highways has proposed amendments to vehicle emission rules to widen the scope for higher ethanol blends and alternative fuels, paving the way for flex-fuel and pure biofuel vehicles across all vehicle categories.

The road transport ministry has proposed changes to emission norms to expand the use of higher ethanol blends and alternative fuels. (PIB)

The draft changes to the Central Motor Vehicles Rules, 1989, notified on April 27, cover fuels including E85 (85% ethanol blended with petrol), E100 (near-pure ethanol), B100 biodiesel and hydrogen-CNG combinations.

Until now, the rules primarily referenced E10 and E20. The proposed amendment opens the regulatory door for flex-fuel and pure biofuel vehicles across all categories, including two-wheelers, three-wheelers, passenger cars and heavy vehicles.

B100 is 100% pure biodiesel, produced from vegetable oils, animal fats or recycled cooking oil; it can run in diesel engines but requires fuel system modifications at full concentration. Hydrogen-CNG is a blend of compressed natural gas with typically 18-20% hydrogen, which burns cleaner than pure CNG and makes use of existing gas infrastructure.

HT reported on April 24 the plans will in effect give consumers the option to buy flex-fuel vehicles capable of running on higher ethanol blends, while conventional petrol and diesel cars will retain the option of lower-concentration fuels such as E20.

What are flex-fuel vehicles?

Flex-fuel vehicles are designed to run on any mixture of ethanol and petrol—from E20 to E100—with onboard sensors adjusting parameters automatically. Transitioning to high-ethanol blends requires vehicle reconfiguration, such as upgrading fuel lines to handle ethanol’s corrosive properties and retuning engine management systems. Brazil launched the world’s most mature flex-fuel programme in 2003, achieving lifecycle carbon reductions of up to 90% over fossil petrol.

Automobile companies say they are prepared for the shift. “Auto companies are ready to launch flex-fuel cars, which emit far less carbon,” said Vikram Gulati, country head of Toyota Kirloskar Motor, told HT last week.

The draft also raises the vehicle weight limit from 3,000kg to 3,500kg, bringing regulations in line with global standards for light commercial vehicles. This brings more vans, pickups and small trucks under the same emission testing rules.

The notification updates fuel definitions, replacing references to “Hydrogen+CN” with “Hydrogen+CNG”. It corrects the measurement unit for emission intensity from “Mg/kWh” to “mg/kWh” and rectifies the World-Harmonised Not-to-Exceed (WNTE) emission limit from 60 to 600.

WNTE is a global methodology setting maximum permissible emission levels during real-world operation.

(With inputs from agencies)