Effective Wednesday, every petrol pump in India will dispense petrol blended with 20% ethanol (E20), following a government mandate announced last month. The nationwide rollout pushes ahead even as most vehicles on the road are not built for the fuel, raising concerns over efficiency and engine wear.
While higher ethanol blending is aimed at reducing India’s crude import dependence amid a global energy crisis following the war in West Asia, vehicle readiness remains limited.
A Mint analysis of vehicle registration data from the transport ministry’s Vahan dashboard shows that fewer than 30% of petrol passenger vehicles and two-wheelers registered in 2025 were ethanol-compliant. About 0.9 million passenger vehicles were ethanol-compliant, against a total 3.36 million registered in 2025. The figures for two-wheelers were 5.2 million and 13.76 million, respectively.
But this is limited to 2025, when most vehicles sold were already equipped with E20-ready engines. A longer-term review shows how limited adoption remains. Based on vehicle registration data for the last 15 years, assuming these vehicles are still on the road, ethanol-compliant vehicles account for only about 3% of passenger vehicles and two-wheelers.
To be sure, there were barely any vehicles registered under the ethanol category in the Vahan database before 2023, contributing to the low penetration figures.
Experts say this reflects a shift in how regional transport offices (RTOs) classify vehicles following the rollout of Bharat Stage VI (BS6) Phase 2 rules in April 2023, rather than a sudden surge in sales.
As E20 petrol becomes the standard fuel at pumps, concerns are growing over its impact on older vehicles that are not ethanol-compliant. These vehicles may see reduced fuel efficiency, corrosion in fuel systems and long-term engine wear.
A survey of over 50,000 petrol vehicle owners by LocalCircles, conducted in early 2026, found that five in 10 owners of pre-2022 vehicles reported a drop in fuel efficiency upon using E20 petrol, while three in 10 reported unusual wear and tear in engine components, fuel lines and carburettors.
To address some of these concerns, the government has mandated a minimum Research Octane Number (RON) of 95 to be sold. It is a premium-grade petrol with a higher resistance to knocking and reduces wear and tear on engine components. Consumers have also seen little price benefit from ethanol blending, adding to resistance.
While India is not alone in promoting ethanol as a cleaner alternative to petrol, the transition has offered limited flexibility to consumers. Other countries, particularly Brazil, made this shift over decades and provided more options.
“There are certain systems in other countries, including the higher adoption of flex-fuel (fuel mixture of petrol and ethanol specifically designed for internal combustion engines) vehicles in Brazil, that we don’t yet have in India,” said Shifali Goyal, research associate at Centre for Social and Economic Progress.