The Indian government has mandated the sale of ethanol-blended petrol with an octane rating of at least 95 RON (research octane number) from April 1, 2026. This will take effect exactly a year after the nationwide rollout of petrol with 20 percent ethanol blend (E20). The government may allow oil firms to sell fuel that meets only the RON specification in special cases and for specific regions or periods. The fuel will be standardised under Bureau of Indian Standards (BIS) specifications to ensure consistency in fuel quality and safety across the country.
Ethanol has a high octane rating of around 108 RON. When blended with petrol at up to 20 percent (E20), it helps increase the fuel's overall octane level. As per oil companies, a 20 percent ethanol blend raises the octane rating by about 6 RON. So, if regular petrol earlier had an octane rating of around 91-92 RON, E20 fuel should now be closer to 97-98 RON.
