India has completed its nationwide shift to E20 petrol, which contains 20% ethanol, ahead of the 2030 target.While the government claims E20 is safe for existing vehicles, concerns persist about reduced fuel efficiency (3-4% lower mileage) and long-term engine compatibility, especially for cars manufactured before 2012.

Automakers like Maruti Suzuki and Hyundai argue that higher ethanol blends like E25 would require extensive testing and validation, citing risks to rubber and plastic fuel system components.

The government has exempted E22-E30 blends from excise duties and is preparing for future ethanol increases, but critics warn that mandatory upgrades could burden older vehicles.E85, a high-ethanol fuel for flex-fuel cars, is being rolled out in major cities, though conventional cars cannot use it without risking damage.The debate highlights tensions between energy security goals and consumer concerns about vehicle reliability and fuel costs.